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China Ocean Engineering 2024年第2期38卷 285-296页

作者： DU Zun-feng ZHU Hai-ming YU jian-xing State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation School of Civil EngineeringTianjin UniversityTianjin 300350China

When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fatigue monitoring of real *** problem is conventionally solved using the modal decomposition method,based on the principle that the response can be approximated by a weighted sum of limited vibration ***,the method is not valid when the problem is underdetermined,i.e.,the number of unknown mode weights is more than the number of known *** study proposed a sparse modal decomposition method based on the compressed sensing theory and the Compressive Sampling Matching Pursuit(Co Sa MP)algorithm,exploiting the sparsity of VIV in the modal *** the validation study based on high-order VIV experiment data,the proposed method successfully reconstructed the response using only seven acceleration measurements when the conventional methods failed.A primary advantage of the proposed method is that it offers a completely data-driven approach for the underdetermined VIV reconstruction problem,which is more favorable than existing model-dependent solutions for many practical applications such as riser structural health monitoring.

关键词： motion reconstruction vortex-induced vibration(VIV) marine riser modal decomposition method compressed sensing

The Complete Classification of Graphs whose Second Largest Eigenvalue of the Eccentricity Matrix is Less Than 1

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1741-1766页

作者： jian feng WANG xing Yu LEI Shu Chao LI Zoran STANIC School of Mathematics and Statistics Shandong University of TechnologyZibo255049P.R.China Faculty of Mathematics and Statistics Central China Normal UniversityWuhan430079P.R.China Faculty of Mathematics University of BelgradeStudentski trg 1611000BelgradeSerbia

The eccentricity matrix of a graph is obtained from the distance matrix by keeping the entries that are largest in their row or column,and replacing the remaining entries by *** matrix can be interpreted as an opposite to the adjacency matrix,which is on the contrary obtained from the distance matrix by keeping only the entries equal to *** the paper,we determine graphs having the second largest eigenvalue of eccentricity matrix less than 1.

关键词： Eccentricity matrix eigenvalue diameter principal submatrix forbidden subgraph

Nitrogen-doped titanium dioxide/schwertmannite nanocomposites as heterogeneous photo-Fenton catalysts with enhanced efficiency for the degradation of bisphenol A

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Journal of Environmental Sciences 2024年第9期143卷 1-11页

作者： xing-xing Qiao Yu-Hang Xu Xiang-Ji Liu Sai-Le Chen Zhou Zhong Ya-feng Li jian Lü Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation College of Resources and EnvironmentFujian Agriculture and Forestry UniversityFuzhou 350002China State Key Laboratory of Photocatalysis on Energy and Environment Fuzhou UniversityFuzhou 350116China

Potential health risks related to environmental endocrine disruptors(EEDs)have aroused research hotspots at the forefront of water treatment ***,nitrogen-doped titanium dioxide/schwertmannite nanocomposites(N-TiO_(2)/SCH)have been successfully developed as heterogeneous catalysts for the degradation of typical EEDs via photo-Fenton *** to the sustainable Fe(Ⅲ)/Fe(Ⅱ)conversion induced by photoelectrons,as-prepared N-TiO_(2)/SCH nanocomposites exhibit much enhanced efficiency for the degradation of bisphenol A(BPA;ca.100% within 60 min under visible irradiation)in a wide pH range of 3.0-7.8,which is significantly higher than that of the pristine schwertmannite(ca.74.5%)or N-TiO_(2)(ca.10.8%).In this photo-Fenton system,the efficient degradation of BPA is mainly attributed to the oxidation by hydroxyl radical(·OH)and singlet oxygen(^(1)O_(2)).Moreover,the possible catalytic mechanisms and reaction pathway of BPA degradation are systematically investigated based on analytical and photoelectrochemical *** work not only provides a feasible means for the development of novel heterogeneous photo-Fenton catalysts,but also lays a theoretical foundation for the potential application of mineral-based materials in wastewater treatment.

关键词： Titanium dioxide Schwertmannite Fenton reaction Environmental endocrine disruptors Photocatalysis

Is appendoscope a new option for the treatment of acute appendicitis?

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World Journal of Gastroenterology 2024年第28期30卷 3386-3392页

作者： Shu-Jiong feng Yi-feng Zhou jian-feng Yang Hong-Zhang Shen Guang-xing Cui Xiao-feng Zhang Department of Gastroenterology Affiliated Hangzhou First People’s HospitalSchool of MedicineWestlake UniversityHangzhou 310000Zhejiang ProvinceChina Department of Gastroenterology Key Laboratory of Integrated Traditional Chinese and Western Medicine for Biliary and Pancreatic Diseases of Zhejiang ProvinceHangzhou 310000Zhejiang ProvinceChina Department of Gastroenterology Hangzhou Institute of Digestive DiseasesHangzhou 310000Zhejiang ProvinceChina

Acute appendicitis is a common surgical *** is commonly caused by obstruction of the appendiceal lumen due to fecaliths,tumors,or lymphoid *** over a century,appendectomy has been the primary treatment for acute *** Groves performed the first open appendectomy in *** 1983,Kurt Semm completed the first laparoscopic appendectomy,heralding a new era in ***,appendectomy is associated with certain complications and a rate of negative *** have suggested controversy over the impact of appendectomy on the development of inflammatory bowel disease and Parkinson’s disease,but an increasing number of studies indicate a possible positive correlation between appendectomy and colorectal cancer,gallstones,and cardiovascular *** the recognition that the appendix is not a vestigial organ and the advancement of endoscopic technology,Liu proposed the endoscopic retrograde appendicitis *** is an effective minimally invasive alternative for treating uncomplicated acute *** team has developed an appendoscope with a disposable digital imaging system operated through the biopsy channel of a colonoscope and successfully applied it in the treatment of *** article provides an overview of the progress in endoscopic treatment for acute appendicitis and offers a new perspective on the future direction of appendiceal disease treatment.

关键词： Acute appendicitis Endoscopic technology Endoscopic retrograde appendicitis therapy Appendoscope Appendiceal disease treatment

Mineralogical properties and co-sintering characteristics of fluxed iron ore with magnetite concentrates

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Journal of Iron and Steel Research International 2024年第2期31卷 318-328页

作者： Le-le Niu Zheng-jian Liu jian-liang Zhang Yao-zu Wang Zhen-xing Yang Si-da Li Chang-dong Shan Ben feng School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing100083China Xinxing Casting Pipe Xinjiang Co. Bayingol841300XinjiangChina

To investigate the feasibility of co-sintering of fluxed iron ore with magnetite concentrates, the mineralogical properties of a novel fluxed iron ore were studied using particle size analysis, microscopic morphology characterization, and X-ray diffraction Rietveld analysis. Following that, the experiments for granulation performance and basic sintering characteristics were designed under seven different fluxed iron ore ratios, and the integrated ranking of different fluxed iron ore ratios was determined using gray relation analysis. Finally, the results of the industrial trails were combined with the feasibility analysis. Test and experimental results show that the fraction of the fluxed iron ore particles larger than 0.5 mm can account for more than 48%, and the particles have two morphologies: spherical-rough and flaky-smooth. Ca elements are found in the form of calcite (CaCO3) and dolomite (CaMg(CO3)2). The average particle size of granules and powder removal rate can be improved from 2.50 to 3.16 mm and 39.60% to 24.20%, respectively, with the increase in the fluxed iron ore ratio. Furthermore, the fluxed iron ore can improve assimilability and liquid fluidity of magnetite concentrates. In terms of overall granulation performance and sintering characteristics, the fluxed iron ore ratios are graded from best to worst as follows: 12%, 15%, 9%, 18%, 21%, 6% and 3%. The industrial trails show that when the fluxed iron ore ratio is increased, the beneficial effect of the superior sintering characteristics of the fluxed iron ore itself is ideally balanced with the negative effect of the lower amount of additional CaO at 12% ratio, and thus, it is feasible to bring the fluxed iron ore into production at a level of roughly 12%.

关键词： Fluxed iron ore Magnetite concentrate Granulation performance Sintering characteristics Gray relation analysis

Concerted Steric and Electronic Strategy in Thermostable Salicylaldiminato Nickel Catalysts for Ethylene(Co)polymerization

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Chinese Journal of Polymer Science 2024年第8期42卷 1085-1092页

作者： Hong-Yu Ji Hong-Liang Mu Chun-feng Tang Yu-xing Zhang Yue Chi Zhong-Bao jian Key Laboratory of Advanced Structural Materials Ministry of EducationSchool of Materials Science and EngineeringChangchun University of TechnologyChangchun 130012China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Olefin polymerization is one of the most im portant chemical reactions in *** work presents a strategy that emphasizes the synergistic meta/poro-steric hindrance of N-aryl groups and electronic effects in newly synthesized neutral salicylaldiminato nickel *** nickel(Ⅱ)catalysts exhibit exceptional thermostability,ranging from 30℃to 130℃,demonstrating enhanced catalytic activities and broadly regulated polyethylene molecular weights(3-341 kg·mol^(-1))and controlled polymer branch density(2-102 brs/1000C).The preferred catalyst Ni3 with concerted steric and electronic effects enables the production of solid-state semi-crystalline polyethylene materials at temperatures below 90℃.Notably,Ni3 exhibits an impressive tolerance of 110℃and can withstand even the challenging polymerization temperature of 130℃,leading to the production of polyethylene wax and ***,functionalized polyethylene is produced.

关键词： Polyolefin Salicylaldiminato ligand Nickel catalyst Oil Wax

Substantial increase of heat-induced labor and economic loss in China under rapid economic and environmental temperature growth

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Advances in Climate Change Research 2024年第4期15卷 708-716页

作者： Bo-Wen CHU jian-feng LUO Ke-Xin WANG Zhen-Cheng xing Hai-Kun WANG Joint International Research Laboratory of Atmospheric and Earth System Sciences School of Atmospheric SciencesNanjing UniversityNanjing 210023China Collaborative Innovation Center of Climate Change Jiangsu ProvinceNanjing 210023China Frontiers Science Center for Critical Earth Material Cycling Nanjing UniversityNanjing 210023China Nanjin-Helski Insiute in Amosperc and Earth System Sciences Nanjing UniversityNanjing 210023China

Exposure to heat stress causes diminished work performance and leads to economic *** the last two decades,China has experienced both rapid economic development and environmental warming;however,the spatiotemporal variations of association between environmental heat and labor loss have been rarely investigated behind this double ***,we evaluated the variation in China's heat-induced labor productivity loss and related economic cost from 2001 to 2019 and investigated the effect of economic development and regional *** found that decline in labor productivity because of heat stress increased significantly(p<0.05 for heavy-intensity work),and the corresponding economic loss also exhibited a drastic increase by 6-to *** relative economic loss showed a slight but nonsignificant increase with an average value of 0.54%of the annual total *** the sub-regional and sectoral level,adverse effects were more prominent in the southeast region,and the secondary industry sectors,such as construction and manufacturing,contributed to larger proportions of economic *** transformation of industrial structure made economic sectors more vulnerable to heat exposure,and increasingly preventive effects of air-conditioning use were noted on economic damage due to heat-induced productivity decline(36.0%relative economic benefits in 2019 compared to 9.7%in 2001).Our findings could provide a deep insight into heat burden on occupational health and heat adaptation strategies regionally under climate change,especially in developing areas with higher temperature and humidity environment.

关键词： Heat stress Labor loss Wet bulb globe temperature China Economic impact

Quantitative characterizations of anisotropic dynamic properties in organic-rich shale with different kerogen content

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Petroleum Science 2024年第2期21卷 855-865页

作者： jian-Yong Xie Yan-Ping Fang xing-Hua Wu jian'er Zhao Jun-Cheng Dai Jun-xing Cao Ji-Xin Deng State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu610059SichuanChina Key Lab of Earth Exploration&Information Techniques of Ministry of Education Geophysical InstituteChengdu University of TechnologyChengdu610059SichuanChina PetroChina Southwest Oil&Gasfield Company Chengdu610017SichuanChina

Understanding the quantitative responses of anisotropic dynamic properties in organic-rich shale with different kerogen content(KC)is of great significance in hydrocarbon exploration and *** controlled experiments with a single variable is challenging for natural shales due to their high variations in components,diagenesis conditions,or pore *** employed the hot-pressing technique to construct 11 well-controlled artificial shale with varying *** artificial shale samples were successive machined into prismatic shape for ultrasonic measurements along different *** revealed bedding perpendicular P-wave velocities are more sensitive to the increasing KC than bedding paralleling velocities due to the preferential alignments of *** elastic stiffnesses except C_(13)are generally decreasing with the increasing KC,the variation of C_(1) and C_(33)on kerogen content are more sensitive than those of C_(44)and C_(66).Apparent dynamic mechanical parameters(v and E)were found to have linear correlation with the true ones from complete anisotropic equations independent of KC,which hold value towards the interpretation of well logs consistently across formations,Anisotropic mechanical parameters(ΔE and brittlenessΔB)tend to decrease with the reducing KC,withΔB showing great sensitivity to KC *** the range of low KC(10%)shale,compilation of data from natural organic rich-shales globally verified the similar systematic relationships that can be empirically used to predict the fraction of KC in shales.

关键词： Elastic properties Organic shale Anisotropy Kerogen content Physical modeling

Systemically functional characterization of regiospecific flavonoid O-methyltransferases from Glycine max

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Synthetic and Systems Biotechnology 2024年第2期9卷 340-348页

作者： Bingtong feng Yuguo jiang Xiaodong Li Yan Wang Ziyu Ren jian Lu xing Yan Zhihua Zhou Pingping Wang Life Science and Technology College Guangxi UniversityNanningGuangxi530004China CAS-Key Laboratory of Synthetic Biology CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai200032China University of Chinese Academy of Sciences Beijing100049China The College of Life Sciences Shanghai Normal UniversityShanghai200234China

Plants produce diverse flavonoids for defense and stress resistance,most of which have health benefits and are widely used as food additives and *** of the free hydroxyl groups of flavonoids,catalyzed by S-adenosyl-l-methionine-dependent O-methyltransferases(OMTs),significantly affects their physicochemical properties and ***(Glycine max)contain a rich pool of O-methylated ***,the OMTs responsible for flavonoid methylation in *** remain largely *** screened the *** genome and obtained 22 putative OMT-encoding genes that share a broad spectrum of amino acid identities(25–96%);among them,19 OMTs were successfully cloned and heterologously expressed in Escherichia *** used the flavonoids containing the free 3,5,7,8,3′,4′hydroxyl group,such as flavones(luteolin and 7,8-dihydroxyflavone),flavonols(kaempferol and quercetin),flavanones(naringenin and eriodictyol),isoflavonoids(daidzein and glycetein),and caffeic acid as substrates,and 15 OMTs were proven to catalyze at least one *** methylation activities of these GmOMTs covered the 3,7,8,3′,4′-hydroxyl of flavonoids and 7,4′-hydroxyl of *** systematic characterization of *** flavonoid OMTs provides insights into the biosynthesis of methylated flavonoids in soybeans and OMT bioparts for the production of methylated flavonoids via synthetic biology.

关键词： Flavonoids O-methyltransferases Glycine max Functional characterization

A Novel Scheme for Compression of Cash Images

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Journal of Electronic Science and Technology 2011年第4期9卷 301-305页

作者： Li Li feng Wang jian-feng Lu Da-xing Zhang with the Department of Computer Science Hangzhou Dianzi University

In the field of economy, there are more and more electronic scanning cash images, which need to be compressed in a higher compression ratio. This paper proposes a specific compression algorithm for cash images. First, according to cash image characteristics and standard JPEG （joint photographic experts group） compression, image re-ordering techniques are analyzed, and the method of modifying some blocks into single color blocks is adopted. Then, a suitable quantization table for cash images is obtained. Experimental results show that the method is effective.

关键词： Compression ratio correlation joint photographic experts group preproeess quantization table re-ordering.