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一种基于云模型的云变异粒子群算法

模式识别与人工智能 2011年第1期24卷 90-96页

作者：张英杰邵岁锋 Niyongabo julius 湖南大学计算机与通信学院长沙410082

基于云模型在定性与定量之间相互转换的优良特性,结合粒子群算法的基本思想,提出一种云变异粒子群优化算法.其核心思想是通过正态云算子实现粒子的进化学习过程和变异操作.利用云模型对粒子的进化和变异进行统一建模,自适应控制粒子的... 详细信息

基于云模型在定性与定量之间相互转换的优良特性,结合粒子群算法的基本思想,提出一种云变异粒子群优化算法.其核心思想是通过正态云算子实现粒子的进化学习过程和变异操作.利用云模型对粒子的进化和变异进行统一建模,自适应控制粒子的搜索范围.典型复杂函数测试表明,云粒子群算法能有效找出全局最优解,特别适宜于多峰值函数寻优.

关键词：云模型粒子群算法数值优化

Higher-order exceptional points in waveguidecoupled microcavities:perturbation induced frequency splitting and mode patterns

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Photonics Research 2023年第10期11卷 I0011-I0021页

作者： julius KULLIG DANIEL GROM SEBASTIAN KLEMBT JAN WIERSIG Institut für Physik Otto-von-Guericke-Universität Magdeburg39106 MagdeburgGermany Technische Physik and Würzburg-Dresden Cluster of Excellence ct.qmat Physikalisches Institut and Wilhelm-Conrad-Röntgen-Research Center for Complex Material SystemsAm HublandUniversity of Würzburg97070 WürzburgGermany

Exceptional points are degeneracies in the spectrum of non-Hermitian open systems where at least two eigenfrequencies and simultaneously the corresponding eigenstates of the Hamiltonian ***,the robust construction of higher-order exceptional points with more than two degenerate eigenfrequencies and eigenstates is challenging but yet worthwhile for *** this paper,we reconsider the formation of higher-order exceptional points through waveguide-coupled microring cavities and asymmetric *** this context,we demonstrate the influence of perturbations on the frequency splitting of the *** generate higher-order exceptional points in a simple and robust way,a mirror-induced asymmetric backscattering approach is *** addition to the exceptional-point enhanced sensing capabilities of such systems,also a cavity-selective sensitivity is achieved for particle *** results are motivated by an effective Hamiltonian description and verified by full numerical simulations of the dielectric structure.

关键词： structure exceptional splitting

Modernism rediscovered

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Modernism rediscovered

Determination of PCDD/Fs and dioxin-like PCBs in food and feed using gas chromatography-triple quadrupole mass spectrometry

作者： (1965-)Serraino Pierluigi Shulman julius.

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Science China Chemistry 2017年第5期60卷 670-677页

作者： Huizhong Sun Pu Wang Honghua Li Yingming Li Shucheng Zheng julius Matsiko Yanfen Hao Weiwei Zhang Dou Wang Qinghua Zhang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China University of Chinese Academy of Sciences Beijing 100049 China Institute of Environment and Health Jianghan University Wuhan 430056 China

A method was developed on a gas chromatograph coupled to a triple quadrupole mass spectrometer(GC-MS/MS) for trace level determination of polychlorinated dibenzo-p-dioxins/dibenzofurans(PCDD/Fs) and dioxin-like polychlorinated biphenyls(DL-PCBs) in food and feed. The results demonstrated good sensitivity and repeatability for PCDD/Fs and DL-PCBs at an extremely low level(10 pg mL^(-1) for 2,3,7,8-TCDD/F), as well as wide linear response of over 3 or 4 orders of magnitude in concentration ranges; 0.5–200 ng mL^(-1) for PeCDD/F and 0.2–2000 ng mL^(-1) for DL-PCBs. The method detection limits for PCDD/Fs and DL-PCBs were in the range from 0.018–0.17 pg g^(-1) to 0.13–0.36 pg g^(-1), respectively. The performance of the GC-MS/MS for food and feed sample analysis showed high precision and accuracy compared to the high resolution gas chromatograph/high resolution mass spectrometer. The results indicated the feasibility of GC-MS/MS as a confirmatory method for the measurement of PCDD/Fs and DL-PCBs in food and feed as required by European Union legislation.

关键词： PCDD/Fs DL-PCBs food feed GC-MS/MS

Atmospheric levels and distribution of Dechlorane Plus in an E-waste dismantling region of East China

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Science China Chemistry 2017年第2期60卷 305-310页

作者： Huizhong Sun Yingming Li Pu Wang Shucheng Zheng julius Matsiko Dou Wang Weiwei Zhang Yanfen Hao Qinghua Zhang Guibin Jiang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085 China University of Chinese Academy of Sciences Beijing 100049 China

Atmospheric concentrations of Dechlorane Plus(DP)were investigated in Taizhou,an electronic-waste(E-waste)dismantling region in East *** air samplers with polyurethane foam(PUF)disks were deployed every three months during the sampling period of September 2009-August *** total DP(syn-and anti-DP)concentrations in air ranged from not detected to 277 pg/m^3,with a mean concentration of 53.9 pg/m^3.A generally declining trend of DP levels was found from the E-waste dismantling region to the peripheral *** median values of total DP concentrations in autumn,winter,spring and summer were 52.2,28.8,39.7 and 30.1 pg/m^3,*** seasonal variations of DP concentrations were mainly associated with the intensity of E-waste dismantling activities and meteorological *** mean value of anti-DP fractional abundance(f_(anti))was 0.74±0.08,which was consistent with those in the commercial DP *** study confirmed a significant emission source related to the distribution of atmospheric DP in the E-waste dismantling area and supplied information for the seasonal variation of DP in the atmosphere.

关键词： Dechlorane Plus air E-waste dismantling seasonal variation

Towards disentangling the classification of freshwater fish trypanosomes

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Marine Life Science & Technology 2023年第4期5卷 551-563页

作者： Peng Zhang Jie Liu Xiao‑Ming Yin Jun‑Yu Zhou julius Lukeš Zhao‑Rong Lun De-Hua Lai Guangdong Provincial Key Laboratory of Aquatic Economic Animals State Key Laboratory of BiocontrolSchool of Life SciencesSun Yat-sen UniversityGuangzhou 510275China BGI Genomics BGI-ShenzhenShenzhen 518083China Institute of Parasitology Biology CentreCzech Academy of SciencesČeskéBudějovice(Budweis)37005Czech Republic Biomedical Research Centre School of ScienceEngineering and EnvironmentUniversity of SalfordSalford M54WTUK

Currently,new species of freshwater fish trypanosomes,which are economically important parasites,are being described based on subjectively selected features,i.e.,their cell morphology and the host *** have performed detailed phylogenetic and haplotype diversity analyses of all 18S rRNA genes available for freshwater fish trypanosomes,including the newly obtained sequences of Trypanosoma carassii and Trypanosoma *** on a sequence similarity of 99.5%,we divide these trypanosomes into 15 operational taxonomic units,and propose three nominal scenarios for distinguishing *** and other aquatic *** find evidences for the existence of a low number of freshwater fish trypanosomes,with *** having the widest geographic and host *** analyses support the existence of an umbrella complex composed of *** and two sister species.

关键词： Freshwaterﬁsh trypanosomes 18S rRNA Morphology Phylogeny

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Funk & soul covers

Funk & soul covers

Antioxidant Effect of Herbs and Spices on Copper Mediated Oxidation of Lower and Very Low Density Lipoprotein

作者： Joaquim Paulo ed. julius Wiedemann.

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中国天然药物 2010年第2期8卷 114-120页

作者： Gabriel A.Agbor Joe A.Vinson julius E.Oben Jeanne Y.Ngogang CRPMT Institute of Medical Research and Medicinal Plants StudiesP.O Box 6163Yaoundé Cameroon Department of Chemistry University of ScrantonScrantonPennsylvania18510 USA Department of Biochemistry University of YaoundéICameroon Department of Physiological Sciences Faculty of Medicine and Biomedical SciencesUniversity of YaoundéICameroon

AIM:The present study investigates the antioxidant effect of two extracts(hydrolyzed and non-hydrolyzed)of five herbs and eight spices in the prevention of LDL+VLDL oxidation promoted by cupric ***:The polyphenolic concentrations of these extracts were measured using Folin-Ciocalteu *** antioxidant quality was analyzed by the determination of lag-time,concentration of polyphenol that will inhibit 50%of oxidation of LDL+VLDL(IC50)and phenol antioxidant index(PAOXI). RESULTS:The hydrolyzed extracts had significant higher polyphenol concentration,longer lag-time,lower IC50 and higher PAOXI than the non-hydrolyzed extracts(P<0.001).Thus,hydrolyzed extract contains better quantity and quality polyphenolic antioxidant than the non-hydrolyzed *** hydrolyzed and non-hydrolyzed extracts were better antioxidants than Vitamin E in the inhibition of LDL+VLDL ***:The reaction rate and concentration of conjugated diene formed suggested that all the extracts had similar reaction mechanism in the prevention of copper mediated LDL+VLDL oxidation.

关键词：抗氧化剂药草水解多酚

电子束蒸发制备高熵合金涂层Al_xFeCoCrNiCu(x=0.25,0.5,1.0)的微观结构和耐腐蚀性能研究（英文）

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稀有金属材料与工程 2017年第12期46卷 3621-3625页

作者：牛雪莲 Jellinek julius 周丹杨桂娟于游大连海洋大学辽宁大连116023 美国阿贡国家实验室伊利诺伊州芝加哥60439

实验采用电子束蒸发法在钢基体表面制备高熵合金(HEA)涂层,探究不同Al元素对微观结构、表面形貌和电化学性能的影响。涂层表面的X射线衍射、电子探针和原子力显微镜实验结果表明,不同成分的合金涂层均呈典型的树枝晶结构,组织中仍保持... 详细信息

实验采用电子束蒸发法在钢基体表面制备高熵合金(HEA)涂层,探究不同Al元素对微观结构、表面形貌和电化学性能的影响。涂层表面的X射线衍射、电子探针和原子力显微镜实验结果表明,不同成分的合金涂层均呈典型的树枝晶结构,组织中仍保持原有的化学组成。涂层表面平整分布均匀,膜层致密。在0.5 mol/L H2SO4溶液和1 mol/L NaCl溶液中,高熵合金的宽钝化区大于700 mV,具有较大的腐蚀电势-129 mV和较小的腐蚀电流密度约2.2×10^(-6) A/cm^2,Al_(0.5)FeCoCrNiCu涂层的耐蚀性最佳。

关键词：高熵合金涂层钢筋耐蚀性