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On Newton’s Method for Solving Nonlinear Equations and Function Splitting

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Numerical Mathematics(Theory,Methods and Applications) 2011年第1期4卷 53-67页

作者： Ioannis K.Argyros saïd Hilout Cameron University Department of Mathematics SciencesLawtonOK 73505USA Universitéde Poitiers Laboratoire de Mathématiques et ApplicationsBd.Pierre et Marie CurieTéléport 2B.P.3017986962 Futuroscope Chasseneuil CedexFrance

We provided in[14]and[15]a semilocal convergence analysis for Newton’s method on a Banach space setting,by splitting the given *** this study,we improve the error bounds,order of convergence,and simplify the sufficie... 详细信息

关键词： Newton’s method Banach space majorizing sequence semilocal convergence splitting of an operator

Two Polyoxometalate-based Host-guest Compounds:Synthesis,Crystal Structure and Catalytic Performance

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Chinese Journal of Structural Chemistry 2021年第12期40卷 1655-1660,1554页

作者： WANG Song-Xia WANG sa-sa WU Xiao-Yuan YANG Wen-Bin LU Can-Zhong Fujian Normal University Fuzhou 350007China CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China

Two polyoxometalate-based host-guest compounds,(HL1)2(HPW12O40)〜11H2O(1),(HL2)3(PWi2O40)·3H2O(2)(L_(1)=guanine,L_(2)=2-(1H-1,2,4-triazol-3-yl)pyridine),were synthesized under hydrothermal conditions and characterized by EA,PXRD,TG,FT-ir and X-ray single-crystal *** 1 crystallizes in trigonal space group P-3 with a=18.2917(5),b=18.2917(5),c=13.5441(5)A,V=3924.5(3)A^(3),Z=3,Mr=3383.26 g/mol,pcak=4.036 g/cm^(3),F(000)=4137,=48.532 mm^(-1),GOOF=1.062,the final R=0.0713 and wR=0.1865 for 9037 observed reflections with I>2σ(I).Compound 2 crystallizes in trigonal space group R-3 with a=19.0017(6),b=19.0017(6),c=25.6361(9)A,V=8016.2(6)A^(3),Z=6,Mr=3372.45 g/mol,p_(calc)=4.188 g/cm,F(000)=8886,μ=47.644 mm^(-1),GOOF=1.077,the final R=0.0380 and wR=0.0976 for 5904 observed reflections with I>2σ(I).These two compounds can catalyze selective oxidation of aniline with H2O2 as the *** optimal conditions,the conversion of aniline with compound 1 can reach up to 91.25%,and the selectivity of nitrosobenzene is 78.81%.

关键词： polyoxometalates catalytic oxidation aniline nitrosobenzene

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New Results on Discrete-time Delay Systems Identification

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International Journal of Automation and computing 2012年第6期9卷 570-577页

作者： sada Bedoui Majda Ltaief Kamel Abderrahim Department of Electrical and Automation Engineering National Engineering School of GabesUniversity of Gabes

A new approach for simultaneous online identification of unknown time delay and dynamic parameters of discrete-time delay systems is proposed in this *** proposed algorithm involves constructing a new generalized regression vector and defining the time delay and the rational dynamic parameters in the same *** gradient algorithm is used to deal with the identification *** effectiveness of this method is illustrated through simulation.

关键词： Time delay identification gradient method discrete-time delay system iterative algorithm.

Fast Calculation of Electromagnetic Forces in IPMSMs Under PWM VSI Supply Based on Small-Signal Time-Harmonic Finite Element Method

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CES Transactions on Electrical Machines and Systems 2022年第1期6卷 67-76页

作者： sa Zhu Jianbo Lu Feng Zeng IEEE College of Energy and Electrical Engineering Hohai UniversityNanjing211100China

This paper introduces a novel method for fast calculating the electromagnetic forces in interior permanent magnet synchronous machines(IPMSMs)under pulse width modulation(PWM)voltage source inverter(VSI)supply based on the small-signal time-harmonic finite element analysis(THFEA),which has been successfully utilized for fast calculating the PWMinduced losses in silicon steel sheets and permanent *** on the small-signal THFEA,the functional relationships between high-frequency harmonic voltages(HFHVs)and corresponding airgap flux densities are established,which are used for calculating the flux density spectra caused by each HFHV in the PWM voltage ***,the superposition principle is applied for calculating the flux density spectra caused by fundamental currents and all HFHVs,which are converted to the electromagnetic force spectra at *** relative errors between the force density spectra calculated with the proposed method and those obtained from traditional time-stepping finite element analysis(TSFEA)using PWM voltages as input are within 3.1%,while the proposed method is 24 times faster than the traditional TSFEA.

关键词： Time-harmonic finite element analysis(THFEA) Interior permanent magnet synchronous machines(IPMSMs) Electromagnetic forces Pulse width modulation Vibration and acoustic noise

The enhancement of performance and imbibition effect of slickwater-based fracturing fluid by using MoS_(2)nanosheets

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Petroleum Science 2023年第4期20卷 2187-2201页

作者： Hang Xu Yuan Li Guo-Lin Yu sa-sa Yang Bo-Jun Li Fu-Jian Zhou Er-Dong Yao Hao Bai Zhi-Yu Liu Unconventional Petroleum Research Institute China University of Petroleum(Beijing)Beijing102249China National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

Slickwater-based fracturing fluid has recently garnered significant attention as the major fluid for volumetric fracturing;however,lots of challenges and limitations such as low viscosity,poor salt tolerance,and possible formation damage hinder the application of the conventional simple slickwater-based fracturing *** addition,nanomaterials have proven to be potential solutions or improvements to a number of challenges associated with the *** this paper,molybdenum disulfide(MoS_(2))nanosheets were chemically synthesized by hydrothermal method and applied to improve the performance of conventional slickwater-based fracturing ***,the microstructure characteristics and crystal type of the MoS_(2)nanosheets were analyzed by SEM,edS,TEM,XPS,and Raman spectroscopy ***,a series of evaluation experiments were carried out to compare the performance of MoS_(2)nanosheet-modified slickwater with the conventional slickwater,including rheology,drag reduction,and sand ***,the enhanced imbibition capacity and potential mechanism of the nanosheet-modified slickwater were systematically *** results showed that the self-synthesized MoS_(2)nanosheets displayed a distinct ultrathin flake-like morphology and a lateral size in the range of tens of *** the nano-composites,each MoS_(2)nanosheet plays the role of cross-linking point,so as to make the spatial structure of the entire system more ***,nanosheet-modified slickwater demonstrates more excellent properties in rheology,drag reduction,and sand *** nanosheet-modified slickwater has a higher apparent viscosity after shearing 120 min under 90℃ and 170 s^(−1).The maximum drag reduction rate achieved 76.3%at 20℃,and the sand settling time of proppants with different mesh in the nano-composites was *** imbibition experiments showed that the gel-breaking fluid of nanosheet-modified slickwater exhibited excellent capability of

关键词： Slickwater-based fracturing fluid MoS_(2)nanosheet Performance evaluation spontaneous imbibition Climbing film

Key Factors Involved in Lamb Quality from Farm to Fork in Europe

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Journal of Integrative Agriculture 2013年第11期12卷 1919-1930页

作者： Carlos saudo Erica Muela María del Mar Campo Department of Animal Production and Food Science University of Zaragoza

World lamb consumption is approximately 2 kg per capita with large variations between continents, e.g., 17 kg in Oceania vs. 0.7 kg in North America. With less than one million tonnes, the international trade of sheep meat contributes to a small percentage of the total meat exchanged between countries. On the other hand, lamb represents the highest rate of species trading in relation to the total sheep meat produced. It is therefore likely to ifnd a wide variability of different lamb products in the same market, and that the conservation procedures （such as refrigeration, packaging or freezing）, chemical composition, especially the fat due to its implication in human health, lfavour development and juiciness perception （affected, i.e., by the feeding or the age or slaughter weight of the animal） and acceptability （based on culinary background） could be considered important indicators of this advantageous situation. In this paper some studies related to the aforementioned indicators are discussed.

关键词： technology chemical composition consumer preferences

Acaricidal activities of whole cell suspension,cell-free supernatant,and crude cell extract of Xenorhabdus stokiae against mushroom mite (Luciaphorus sp.)

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第4期13卷 261-266页

作者： Prapassorn BUSsaMAN Chirayu sa-UTH Paweena RATTANASENA Angsumarn CHANDRAPATYA Biocontrol Research Unit Department of BiotechnologyMahasarakham UniversityMaha Sarakham 44150Thailand Department of Entomology Kasetsart UniversityChatuchakBangkok 10900Thailand

Xenorhabdus bacterium has been used as a biological control agent against Luciaphorus sp., a mushroom mite endemic in Thailand. To develop an effective formulation ofXenorhabdus stokiae, treatments using different parts of X. stokiae isolate PB09 culture, including whole cell suspension, cell-free supernatant, and crude cell extract, were performed. The results show that different parts ofX. stokiae isolate PB09 culture could induce variable effects on mite mortality and fecundity. Application with cell-free supernatant of X. stokiae culture resulted in both the highest mite mortality rate [（89.00＋3.60）%] and the lowest mite fecundity [（41.33_＋23.69） eggs/gravid female]. Whole cell suspen- sion of X. stokiae isolate PB09 culture was found to be slightly less effective than its cell-free supernatant, suggesting that X. stokiae was more likely to release its metabolites with acaricidal activities to the surrounding culture media. Crude cell extract of X. stokiae was not effective against mites. Cell-free supematant of X. stokiae isolate PB09 was the most effective biological control agent and it could be conveniently used in future formulations instead of live bacteria.

关键词： Xenorhabdus Luciaphorus Whole cell suspension Cell-free supematant Crude cell extract Mushroom mite

Thirteen-year growth response of ponderosa pine plantations to dominant shrubs(Arctostaphylos and Ceanothus)

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Journal of Forestry Research 2020年第4期31卷 1445-1451页

作者： Jianwei Zhang Matt D.Busse Gary O.Fiddler ed Fredrickson USDA Forest Service Pacific Southwest Research Station3644 Avtech ParkwayReddingCA 96002USA USDA Forest Service Pacific Southwest Region3644 Avtech ParkwayReddingCA 96002USA Thunder Road Resources 21169 Falling Leaf RdReddingCA 96003USA

Thirteen-year growth response of ponderosa pine to various manipulations of understory vegetation was studied to determine if a threshold of understory cover can be established for plantation productivity and whether nitrogen-fixing Ceanothus species benefit plantation growth compared to non N-fixing Arctostaphylos species,given their ability to improve site *** showed that completely controlling competing vegetation increased plantation growth,as was universally expected,but the effects of partial shrub control on plantation performance was *** did not find a benefit of nitrogenfixing shrubs on tree growth,as young plantation growth was slightly better in the non N-fixing plots compared to the N-fixing plots due to differences in shrub *** understory cover threshold for tree growth was not *** to the overriding effect of shrub competition,controlling herbaceous species had little effect on plantation growth even though it benefited tree seedling survival.A long-term value of N-fixing shrubs at these sites,if there is one,must be balanced by successful plantation establishment and rapid early growth.

关键词： Competing vegetation control Manzanita Nitrogen-fixing Ceanothus Pinus ponderosa growth Shrub cover

Metalloporphyrin-based covalent organic frameworks composed of the electron donor-acceptor dyads for visible-light-driven selective CO2 reduction

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Science China Chemistry 2020年第9期63卷 1289-1294页

作者： Haowei Lv Rongjian sa Pengyue Li Daqiang Yuan Xinchen Wang Ruihu Wang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Institute of Oceanography Ocean CollegeMinjiang UniversityFuzhou 350108China State Key Laboratory of Photocatalysis on Energy and Environment Fuzhou UniversityFuzhou 350108China

The visible-light-driven photocatalytic CO2 reduction with high efficiency is highly desirable but ***,we present porphyrin-tetraphenylethene-based covalent organic frameworks(MP-TPE-COF,where M=H2,Co and Ni;TPE=4,4′,4″,4?-(ethane-1,1,2,2-tetrayl)tetrabenzaldehyde;COF=covalent organic framework)as ideal platforms for understanding photocatalytic CO2 reduction at molecular *** and theoretical investigations have demonstrated crucial roles of metalloporphyrin units in selective adsorption,activation and conversion of CO2 as well as in the separation of charge carriers and electron transfer,thus allowing for flexible modulation of photocatalytic activity and *** P-TPE-COF exhibits high CO evolution rate of 2,414μmol g-^1 h^-1 with the selectivity of 61%over H2 generation under visible-light irradiation,while Ni P-TPE-COF provides CO evolution rate of 525μmol g^-1 h^-1 and 93%selectivity with superior ***,the photocatalytic system is feasible for the simulated flue gas,which provides CO evolution rate of 386μmol g-1 h-1 and selectivity of 77%.This work provides in-depth insight into the structure-activity relationships toward the activation and photoreduction of CO2.

关键词： covalent organic frameworks photocatalysis porous materials CO2reduction metalloporphyrin