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Colloidal Dispersion of Nano-Ru/SiO_2 in PEG and its Application for Hydrogenation of Benzene

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Chinese Chemical Letters 2006年第10期17卷 1413-1416页

作者： yu Chuan yang Yan chen Yan Hua WANG Jing yang JIANG Zi Lin JIN State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012

Colloidal dispersion of nano-Ru/SiO2 in PEG （polyethylene glycol, M.W.=400） was used for benzene hydrogenation. The system has the features of easy catalyst＇s recycling and high catalyst stability.

关键词： Ru nanoparticles PEG benzene hydrogenation nano-Ru/SiO2

Enhanced expressions and activations of leukotriene C4synthesis enzymes in D-galactosamine/lipopolysaccharide-induced rat fulminant hepatic failure model

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World Journal of Gastroenterology 2008年第17期14卷 2748-2756页

作者： Kui-Fen Ma Hong-yu yang Zhe chen Luo-yang Qi Dan-Yan Zhu Yi-Jia Lou Institute of Pharmacology & Toxicology andBiochemical Pharmaceutics College of Pharmaceutical SciencesZlaejiang University Hangzhou 310058 Zhejiang Province China

AIM： To investigate the expression and activity of leukotriene C4 （LTC4） synthesis enzymes and their underlying relationship with cysteinyl leukotriene （cys-LT） generation in a rat fulminant hepatic failure （FHF） model induced by D-galactosamine/lipopolysaccharide （D-GaIN/ LPS）. METHODS： Rats were treated with D-GaIN （300 mg/kg） plus LPS （0.1 mg/kg） for 1, 3, 6, and 12 h. Enzyme immunoassay was used to determine the hepatic cys-LT content. Reverse transcription-polymerase chain reaction （RT-PCR）, Western blot or immunohistochemical assay were employed to assess the expression or location of LTC4 synthesis enzymes, which belong to membrane associated proteins in eicosanoid and glutathione （MAPEG） metabolism superfamily. Activity of LTC4 synthesis enzymes was evaluated by determination of the products of LTA4 after incubation with liver microsomes using high performance liquid chromatography （HPLC）. RESULTS： Livers were injured after treatment with D-GaIN/LPS, accompanied by cys-LT accumulation at the prophase of liver injury. Both LTC4 synthase （LTC4S） and microsomal glutathione-S-transferase （mGST） 2 were expressed in the rat liver, while the latter was specifically located in hepatocytes. Their mRNA and protein expressions were up-regulated at an earlier phase after treatment with D-GaIN/LPS. Meantime, a higher activity of LTC4 synthesis enzymes was detected, although theactivity of LTC4S played the main role in this case. CONCLUSION： The expression and activity of both LTC4S and mGST2 are up regulated in a rat FHF model, which are, at least, partly responsible for cys-LT hepatic accumulation.

关键词： Cysteinyl leukotriene Micmsomal glutathioneS-transferase 2 Leukotriene C4 synthase D-galacto-samine/lipopolysaccharide Fulminant hepatic failure

Study on the area ratio of Nb–Sn target for the preparation of Nb_(3)Sn films

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Radiation Detection Technology and Methods 2019年第3期3卷 289-293页

作者： Shuang-Kai chen yu-chen yang Di-Zhou Guo Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Introduction Niobium is extremely important in SRF cavities because of its superconducting ***,there are some intrinsic limits of Nb cavities that cannot meet the requirements of future *** is therefore of utmost importance to look into materials offering SRF performances beyond ***3Sn is the most promising *** our work,the cathode target is cylindrical and rotatable,containing both Nb and Sn elements,which are simultaneously charged,aiming to explore the area ratios of the two elements required in the cathode target by simulation and experiments,*** work will provide the basis for the subsequent Nb3Sn cathode target *** and experiments In the simulation,we calculated stoichiometric ratio and sputtering yield to obtain the area ratios of Nb and *** the experiment,we calculated the rotation rate of the target,deposition thickness of films on substrates and deposition rate to obtain the area ratio of Nb and *** In conclusion,we compared the simulation and experimental results and found that they are in good *** simulation and experimental results also showed that the area ratio of Nb to Sn in the target is close to 9:*** results lay the foundation for the subsequent Nb3Sn cathode target fabrication and multilayer deposition of Nb3Sn thin films.

关键词： Magnetron sputtering Nb3Sn deposition simulation SEM

Particle concentration effect in adsorption/desorption of Zn(Ⅱ) on anatase type nano TiO_2

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Journal of Environmental Sciences 2007年第12期19卷 1442-1445页

作者： yang yu-huan chen Hao PAN Gang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China.

Adsorption/desorption in a new Zn（Ⅱ）-TiO2 adsorption system was investigated at different particle concentrations （Cp）. TEM, SEM and XRD analyses revealed that the TiO2 particles were an aggregation of nano-sized （approximately 10 nm） pure anatase-type TiO2. Adsorption experiments were carried out with particle concentrations of 100, 400 and 1000 mg/L, and their adsorption isotherms were found to decline successively, showing an obvious Cp effect. Desorption experiments indicated that adsorption in this system was irreversible, and the irreversibility increased with increasing Cp. These phenomena could be explained by the MEA （metastable equilibrium adsorption） theory and the Cp effect could be modeled well with an MEA-Freundlich-type Cp effect isotherm equation. This study may heln understand environmental behavior of contaminants on ultrafine natural particles.

关键词： Zn(Ⅱ) anatase-type Ti02 particle concentrations effect adsorption desorption

Precise gradient separation of nanoparticles using reduced graphene oxide-polyoxomolybdate membranes

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Science China Chemistry 2025年第1期68卷 209-216页

作者： Yixin yang Wanlei Zhao Ruoxuan Zheng Hongqiang Li Wei chen yu-Fei Song State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Quzhou Institute for Innovation in Resource Chemical Engineering

The purification and size sieving of nanoparticles （NPs） represents a significant scientific ***,the r GO-polyoxometalates (POMs=PMo12,Mo132and Mo368) membranes were fabricated successfully via a simple and scalable POMsassisted in-situ photoreduction *** the mass ratio of r GO to PMo12was 1:30,the resultant r GO-PMo12membranes with highly ordered and uniform nanochannels of 1.0 nm can be obtained,which showed an accurate carbon quantum dots（CQDs） separation with a cut-off size approximately 1.0 *** increase of the size of the interlayered POMs from PMo12（1.0 nm）,{Mo132}（2.9 nm） to{Mo368}（3.8 nm）,the resultant r GO-PMo12,r GO-Mo132and r GO-Mo368exhibited precise gradient separation of CQDs and Au nanoparticles by size exclusion *** results pave a promising way to construct new twodimensional （2D） membranes for highly efficient size-selective separation.

关键词： reduced graphene oxide polyoxometalates membranes gradient separation nanoparticles

Fabrication of Novel Scaffolds Containing Collagen-I/Polylactic Acid/Nanohydroxyapatite via Co-electrospinning Methods

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Chemical Research in Chinese Universities 2010年第4期26卷 662-666页

作者： ZANG Jun-ting QI Xin LI Shu-qiang LI Dong-song GONG yu-bao yang chen XU Feng LIU Jian-guo Department of Bone and Joint Surgery First Hospital of Jilin University Changchun 130021 P R. China

A novel scaffold containing collagen-I/polylactic acid（PLA）/nanohydroxyapatite（nHA） was prepared via co-electrospinning method. Different target substrates were used to improve the collection efficiency of this scaffold. The properties of the novel scaffold were compared with those of conventionally prepared ones. Compared to con- ventional method, the modified method was more efficient in producing the scaffold. Moreover, the porosity, thickness, and morphology of the novel scaffold were better than those of scaffolds prepared by conventional methods. The properties of collagen-I, collagen-I/PLA and collagen-I/PLA/nHA scaffolds were also compared. Diameters of the electrospun fibers ranged from 180 to 405 nm, and roughness was present on the surface of the fibers due to the deposition of crystals of nHA along the long axis of the fibers. The fibers of the collagen-I/PLA/nHA scaffold and the fibers of natural bone tissue had similar structure.

关键词： Electrospinning Collagen-I PLA Nanohydroxyapatite

Engine Misfire Fault Detection Based on the Channel Attention Convolutional Model

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Computers, Materials & Continua 2025年第1期82卷 843-862页

作者： Feifei yu Yongxian Huang Guoyan chen Xiaoqing yang Canyi Du Yongkang Gong School of Mechatronic Engineering Guangdong Polytechnic Normal UniversityGuangzhou510665China School of Automotive and Transportation Engineering Guangdong Polytechnic Normal UniversityGuangzhou510665China

To accurately diagnosemisfire faults in automotive engines,we propose a Channel Attention Convolutional Model,specifically the Squeeze-and-Excitation Networks(SENET),for classifying engine vibration signals and precisely pinpointing misfire *** the experiment,we established a total of 11 distinct states,encompassing the engine’s normal state,single-cylinder misfire faults,and dual-cylinder misfire faults for different *** collection was facilitated by a highly sensitive acceleration signal collector with a high sampling rate of 20,*** collected data were methodically divided into training and testing sets based on different experimental groups to ensure generalization and prevent overlap between the two *** results revealed that,with a vibration acceleration sequence of 1000 time steps(approximately 50 ms)as input,the SENET model achieved a misfire fault detection accuracy of 99.8%.For comparison,we also trained and tested several commonly used models,including Long Short-Term Memory(LSTM),Transformer,and Multi-Scale Residual Networks(MSRESNET),yielding accuracy rates of 84%,79%,and 95%,*** underscores the superior accuracy of the SENET model in detecting engine misfire faults compared to other ***,the F1 scores for each type of recognition in the SENET model surpassed 0.98,outperforming the baseline *** analysis indicated that the misclassified samples in the LSTM and Transformer models’predictions were primarily due to intra-class misidentifications between single-cylinder and dual-cylinder misfire *** delve deeper,we conducted a visual analysis of the features extracted by the LSTM and SENET models using T-distributed Stochastic Neighbor Embedding(T-SNE)*** findings revealed that,in the LSTMmodel,data points of the same type tended to cluster together with significant ***,in the SENET model,data points of various types were more widely and evenly dispersed,demonstra

关键词： Channel attention SENET model engine misfire fault fault detection

Gene Expression Profile Identifies LncRNA AL355974.3 As a Potential Glioma Biomarker

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Current Medical Science 2024年第5期44卷 1047-1057页

作者： Hao-tian LU yu-yang chen Yong-jia yu Xing-sheng LIAO Hui LIANG Lun LIANG Pan-lin MO Xin-kai HUANG Shuai DING Chang LIU Da-qin FENG Department of Neurosurgery The First Affiliated HospitalGuangxi Medical UniversityNanning530021China

Objective Glioma is a central nervous system tumor arising from glial *** significant advances in diagnosis and treatment,most patients with high-grade gliomas have a poor *** studies have shown that long noncoding RNAs(lncRNAs)may play important roles in the development,progression and treatment of many tumors,including *** targeted therapy may be a new direction for the adjuvant treatment of ***,we hope that by studying differentially expressed lncRNAs(DElncRNAs)in glioma,we can discover lncRNAs that can serve as biomarkers for glioma and provide better therapeutic modalities for glioma *** First,the expression of lncRNAs in 5 normal brain(NB)tissues and 10 glioma tissues was examined by RNA sequencing(RNA-seq).Next,we performed Kaplan-Meier analysis of data from The Cancer Genome Atlas(TCGA)database to assess the prognostic value of these ***,functional analysis of the DElncRNAs was performed by means of Gene Ontology(GO)enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway *** RNA sequencing analysis revealed 85 upregulated miRNAs and 71 downregulated lncRNAs in low-grade glioma(LGG)and 50 upregulated lncRNAs and 70 downregulated lncRNAs in glioblastoma(GBM).Among them,AL355974.3 was the most upregulated ***00632 was the most downregulated ***,LGG patients with higher AL355974.3 expression had worse overall survival according to Kaplan-Meier analysis of the TCGA ***,bioinformatics analysis revealed that the target genes of these DElncRNAs were enriched in various biological processes and signaling pathways,such as cell metabolic and developmental *** Our findings provide evidence that AL355974.3 may be a new biomarker for glioma.

关键词： glioma long noncoding RNAs biomarker RNA sequencing

Soil C and N Pools in Chinese Fir and Evergreen Broadleaf Forests and their Changes with Slash Burning in Mid-Subtropical China

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Pedosphere 2006年第1期16卷 56-63页

作者： GUO Jian-Fen yang yu-Sheng chen Guang-Shui XIE Jin-Sheng LIN Peng College of Life Science Xiamen University Xiamen 361005 （China） College of Geography Science Fujian Normal University Fuzhou 350007 （China） College of Forestry Fujian Agriculture and Forestry University Fuzhou 350002 （China）

Soil organic carbon （C） and total nitrogen （N） pools of a Chinese fir （Cunninghamia lanceolata （Lamb.） Hook.）（CF） forest, and an evergreen broadleaf （EB） forest located in mid-subtropical, southeastern China, were compared before clearcutting, with the effect of slash burning on organic C and total N in the top 10 cm of soil before and after burning also being evaluated. Prior to clearcutting CF forest had significantly lower （P 〈0.05） organic C and total N in the soil （0-100 cm） compared to EB forest with approximately 60% of the C and N at the two forest sites stored at the 0 to 40 cm soil. In post-burn samples of the 0-10 cm depth at 5 days, 1 year, and 5 years for CF and EB forests, significantly lower levels （P 〈0.05） of organic C and total N than those in the pre-burn samples were observed. Compared to the pre-burn levels, at post-burn year 5, surface soil organic C storage was only 85% in CF forest and 72% in EB forest, while total N storage was 77% for CF forest and 73% for EB forest. Slash burning caused marked long-term changes in surface soil C and N in the two forest types.

关键词： Chinese fir evergreen broadleaf forest slash burning soil carbon soil nitrogen