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Effect of vanadium addition on microstructure and properties of AI_(0.5)Cr_(0.9)FeNi_(2.5)multi-principal alloys

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Journal of Iron and Steel Research International 2021年第5期28卷 586-596页

作者： de-xi Hao Nan-nan Zhang Yue Zhang de-yuan Li department of Material Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina Provincial Key Laboratory of Advanced Welding Technology and Automation Shenyang 110870LiaoningChina

AI_(0.5)Cr_(0.9)FeNi_(2.5)V_(x)(x=0,0.2,0.4,0.6,0.8,1.0)multi-principal alloys were prepared by vacuum arc *** effect of vanadium addition on its microstructure and properties was *** results show that the alloys of all components exhibited an FCC single-phase *** the addition of vanadium,the microstructure of the alloy changed from dendrites to equiaxed crystals,the grains were remarkably refined,and the layered CrV phase was exhibited,which improved the properties of the *** yield strength of the alloy was slightly improved,and the alloys with various components presented good *** V content reached 0.8,the yield strength was 600 MPa,and no fracture ***-wear testing showed that the wear debris was reduced with the addition of V *** sample with V element content of 0.4 had the best friction and wear *** surface grooves became shallow,the worn debris was less,and the wear mechanism was mainly abrasive *** polarisation curve showed that the alloy with V element content of 0.2 has the best corrosion *** passivation interval reached 900 *** corrosion potential and the corrosion current density were-496.299 mV and 2.759μA/cm^(2),respectively.

关键词： Multi-principal alloy Vacuum arc melting CrV phase Adhesive wear Electrochemical testing

Chandler Wobble Period and Q derived by Wavelet Transform

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Chinese Journal of Astronomy and Astrophysics 2004年第3期4卷 247-257页

作者： de-ChunLiao Yong-HongZhou ShanghaiAstronomicalObservatory ChineseAcademyofSciencesShanghai200030 NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012

We apply complex Morlet wavelet transform to three polar motion data series,and derive quasi-instantaneous periods of the Chandler and annual wobble by differencing the wavelettransform results versus the scale factor, and then find their zero points. The results show thatthe mean periods of the Chandler (annual) wobble are 430.71+-1.07 (365.24+-0.11) and 432.71+-0.42(365.23+-0.18) mean solar days for the data sets of 1900-2001 and 1940-2001, respectively. Themaximum relative variation of the quasi-instantaneous period to the mean of the Chandler wobble isless than 1.5% during 1900-2001 (3%-5% during 1920-1940), and that of the annual wobble is less than1.6% during 1900-2001. Quasi-instantaneous and mean values of Q are also derived by using theenergy density―period profile of the Chandler wobble. An asymptotic value of Q = 36.7 is obtainedby fitting polynomial of exponential of σ^(-2) to the relationship between Q and σ during1940-2001.

关键词： polar motion chandler wobble wavelet transform instantaneous period

Application of Arbuscular Mycorrhizal Inocula Might Be A Promising Method in the Restoration of Severely degraded Wetlands

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湿地科学 2013年第1期11卷 21-26页

作者： de Gao department of Natural Resources Management Texas Tech UniversityLubbockTX79409U.S.A.

The application of arbuscular mycorrhizal (AM) inocula in severely degraded wetlands could ensure success in *** fungi play an important role in plant individual's survival and development in a low nutrient *** on the importance that mycorrhizal fungi have to their host plants,mycorrhizal inocula have been produced and applied in terrestrial ecosystems in order to let the plants become ***,mycorrhizal inocula have not been used in wetland restorations,despite increasing evidence that mycorrhizal fungi are commonly found in various wetland systems and have the ability to survive under anoxic *** also shows that mycorrhizal fungal inocula in the soil could have been destroyed in the degraded wetland or could be destroyed during traditional wetland restoration ***,AM inocula production is strongly recommended for wetland *** this paper,I will argue that AM inocula production is required when introduced recovery is necessary,and aeroponic culture technique is a preferable method to produce AM ***,a renewed wetland restoration flow chart is summarized.

关键词： arbuscular mycorrhiza mycorrhizal inocula wetland restoration aeroponic culture technique

Where does selective laser trabeculoplasty stand now? A review

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Eye and Vision 2016年第1期3卷 75-83页

作者： Myrjam de Keyser Maya de Belder Simon de Belder Veva de Groot department of Medicine University of AntwerpUniversiteitsplein 1B-2610 AntwerpBelgium Medipolis Boomsesteenweg 223B-2610 AntwerpBelgium Faculty of Psychology and Education Department of Experimental PsychologyGhent UniversityHenri Dunantlaan 2B-9000 GhentBelgium department of Ophthalmology University Hospital AntwerpWilrijkstraat 10B-2650 EdegemBelgium

Background:Chronic treatment of glaucoma can present a challenge in patients who lack the means and/or the discipline to use daily glaucoma *** wondered if selective laser trabeculoplasty(SLT)could be a useful ***:Inclusion criteria:controlled trials comparing efficacy of SLT in adult patients with any form of open angle glaucoma or ocular hypertension and case reports on side effects of *** recent meta-analyses identified eight randomized clinical trials(RCTs)comparing the effect of SLT with medication(prostaglandin analogs)and with argon laser trabeculoplasty(ALT).We took these eight RCTs as reference base and calculated their success rates where they were not *** articles were added to elaborate on technique and side ***:Mean intraocular pressure(IOP)reduction after SLT was 3.8–8.0 mmHg after 6 months to 1 *** success rate of SLT at 6 months to 1 year is 55–82%.Higher IOP before laser predicts a higher IOP-lowering *** terms of mean IOP reduction,reduction in number of medications and treatment success,the effect of SLT was found to show no clinically relevant difference from that of contemporary medication(prostaglandin analogs)and from ***:The evidence indicates that SLT is an efficacious primary or adjunctive therapy for treating glaucoma.

关键词： Glaucoma Selective laser trabeculoplasty Review Open angle glaucoma Glaucoma treatment Ocular hypertension

Spatial Analysis of <i>Leptospira</i>in Rats, Water and Soil in Bantul District Yogyakarta Indonesia

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Open Journal of Epidemiology 2015年第1期5卷 22-31页

作者： Hadi sumanta Tri Wibawa Suwarno Hadisusanto Anik Nuryati Hari Kusnanto Center for Environmental Health Engineering and Disease Control Yogyakarta Indonesia Student of Doctoral Program Faculty of Medicine Gadjah Mada University Yogyakarta Indonesia department of Microbiology Faculty of Medicine Gadjah Mada University Yogyakarta Indonesia department of Biology Faculty of Biology Gadjah Mada University Yogyakarta Indonesia department of Health Analyst Yogyakarta Health Polytechnic Yogyakarta Indonesia department of Public Health Faculty of Medicine Gadjah Mada University Yogyakarta Indonesia

Leptospirosis is a potential threat to public health. An increasing number of people infected with Leptospira were reported in Bantul District, Yogyakarta special region with a case fatality rate (CFR) of 7.8%. Infected areas in the district have increased from 2 to 15 sub districts. Leptospirosis is caused by Leptospira bacteria and spread by direct contact with infected rodents and indirect contact through contaminated water or soil. Leptospira in rats, water and soil were detected using real-time quantitative polymerase chain reaction (qPCR). The sites of sampled materials were geocoded using Global Positioning System (GPS). Spatial analysis was used to predict the spread of Spira. This study aims to perform the mapping, clustering, and predicting the spread of Leptospira in Bantul Yogyakarta Indonesia. Data were collected from three sub-districts: Sedayu, Sewon and Bantul. The result showed that 38.04% from 368 samples were Spira positive. There were four significant clusters of infection spread source. Spira is predicted to spread in, and out from, Bantul District.

关键词： Leptospirosis Leptospira Rats Water Soil Spatial Analysis

Partition coefficient prediction of Baker's yeast invertase in aqueous two phase systems using hybrid group method data handling neural network

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Chinese Journal of Chemical Engineering 2017年第5期25卷 652-657页

作者： Carlos Eduardo de Araújo Padilha Sérgio Dantas de Oliveira Júnior Domingos Fabiano de Santana Souza Jackson Araújo de Oliveira Gorete Ribeiro de Macedo Everaldo Silvino dos Santos Laboratory of Biochemical Engineering Chemical Engineering DepartmentFederal University of Rio Grande do Norte (UFRN)

A hybrid GMDH neural network model has been developed in order to predict the partition coefficients of invertase from Baker's yeast. ATPS experiments were carried out changing the molar average mass of PEG(1500–6000 Da), p H(4.0–7.0), percentage of PEG(10.0–20.0 w/w), percentage of MgSO_4(8.0–16.0 w/w), percentage of the cell homogenate(10.0–20.0 w/w) and the percentage of MnSO_4(0–5.0 w/w) added as cosolute. The network evaluation was carried out comparing the partition coefficients obtained from the hybrid GMDH neural network with the experimental data using different statistical metrics. The hybrid GMDH neural network model showed better fitting(AARD = 32.752%) as well as good generalization capacity of the partition coefficients of the ATPS than the original GMDH network approach and a BPANN model. Therefore hybrid GMDH neural network model appears as a powerful tool for predicting partition coefficients during downstream processing of biomolecules.

关键词： Partitioning Invertase Aqueous Two Phase System GMDH Neural network

A power-law-based approach to mapping COVID-19 cases in the United States

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Geo-Spatial Information Science 2021年第3期24卷 333-339页

作者： Bin Jiang Chris de Rijke Faculty of Engineering and Sustainable development Division of GIScienceUniversity of GävleGävle80176Sweden

This paper examines the spatial and temporal distribution of all COVID-19 cases from January to June 2020 against the underlying distribution of population in the United *** is found that,as time passes,COVID-19 cases become a power law with cutoff,resembling the underlying spatial distribution of *** power law implies that many states and counties have a low number of cases,while only a few highly populated states and counties have a high number of *** further differentiate patterns between the underlying populations and COVID-19 cases,we derived their inherent hierarchy or spatial heterogeneity characterized by the *** found that the ht-index of COVID-19 cases persistently approaches that of the populations;that is,5 and 7 at the state and county levels,*** the ht-index of COVID-19 cases against that of populations shows that the pandemic is largely shaped by the underlying population with the R-square value between infection and population up to 0.82.

关键词： Power laws head/tail breaks hierarchy spatial heterogeneity ht-index

On the Fourier Spectra of Distributions in Clifford Analysis

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Chinese Annals of Mathematics,Series B 2006年第5期27卷 495-506页

作者： Fred BRACKX Bram de KNOCK Hennie de SCHEPPER Clifford Research Group department of Mathematical Analysis Faculty of EngineeringGhent UniversityGalglaan 29000 GentBelgium

In recent papers by Brackx, delanghe and Sommen, some fundamental higher dimensional distributions have been reconsidered in the framework of Clifford analysis, eventually leading to the introduction of four broad classes of new distributions in Euclidean space. In the current paper we continue the in-depth study of these distributions, more specifically the study of their behaviour in frequency space, thus extending classical results of harmonic analysis.

关键词： Fourier spectra Distributions Clifford analysis

Dynamics of mediterranean pine forests reforested after fires

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Journal of Forestry Research 2023年第2期34卷 345-354页

作者： Álvaro Enríquez-de-Salamanca departamento de Biodiversidad Ecología y EvoluciónFacultad de Ciencias BiológicasUniversidad Complutense de MadridMadridSpain Draba Ingeniería y Consultoría Medioambiental San Lorenzo de El EscorialSpain

Forest fires are frequent under a Mediterranean climate and have shaped the landscape of the region but are currently altered by human action and climate *** have historically conditioned the presence of pine forests,depending on severity and forest *** of Mediterranean pine forests is not always successful,and a transition to shrublands or stands of resprouting species can occur,even after *** study analyses vegetation changes in two Mediterranean pine forests after severe fires and both *** pines had difficulty to regenerate,even despite post-fire *** problem is the difficulty of young seedlings to survive,possibly due to increased summer *** are greater in pine species at the limit of their ecological tolerance:Pinus pinea had a much better recovery success while *** and *** virtually *** pinaster had intermediate results but recovery was generally poor.A transition has taken place in many burnt areas to scrubland or to thickets of the resprouting Quercus rotundifolia,although it is not possible to know whether they will evolve into forests or remain in a sub climatic *** species may increase fire severity but facilitates post-fire ***-fire recovery difficulties are closely linked to issues of natural *** could initiate the disappearance of pine forests,but even in the absence of fire they may disappear in the long-term due to the lack of *** is needed to increase the resilience of these forests,ensuring natural regeneration,and incorporating resprouting species in the understorey.

关键词： Mediterranean region Pine forests Post-fi re recovery Vegetation dynamics Wildfi re transitions