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Improvement in hot corrosion resistance of dissimilar alloy 825 and AISI 321 CO2-laser weldment by HVOF coating in aggressive salt environment at 900℃

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International Journal of Minerals,Metallurgy and Materials 2020年第11期27卷 1536-1550页

作者： S.M.Muthu M.Arivarasu t.Hari Krishna Supriyo Ganguly K.V.Phani Prabhakar Saurav Mohanty School of Mechanical Engineering Vellore Institute of TechnologyVelloreTamil Nadu 632014India Center for Innovative Manufacture Research Vellore Institute of TechnologyVelloreTamil Nadu 632014India Welding Engineering and Laser Processing Centre Cranfield UniversityBedfordUnited Kingdom CLPM International Advanced Research Centre for Powder Metallurgy&New Materials(ARCI)HyderabadIndia Department of Mechanical Engineering North Carolina State UniversityRaleighUSA

this study investigated the hot corrosion performance of a dissimilar weldment of Ni-based superalloy and stainless steel joined by CO2-laser welding and improved by high-velocity oxy-fuel(HVOF)coating in a Na2SO4-60wt%V2O5 environment at 900℃.A dissimilar butt joint of AISI 321 and alloy 825 was fabricated by CO2-laser welding with low heat input after obtaining the optimum welding parameters by bead-on-plate *** metallurgical and mechanical properties of the laser weldment were *** tensile test results indicated the occurrence of fracture in the base metal AISI 321 *** HVOF process was employed to coat Ni-20wt%Cr on the *** evaluate the surface morphology of the corrosion products formed on the uncoated and Ni-20wt%Cr-coated weldments,scanning electron microscopy(SEM)analysis was ***-dispersive spectroscopy(EDS)was used to determine the different elements present on the surface *** existence of oxide phases on the weldments was determined by X-ray diffraction(XRD).the cross sections of the weldments were characterized by SEM with EDS line mapping *** results indicated that the Ni-20wt%Cr-coated weldment exhibited superior hot corrosion resistance due to the development of Cr2O3 and NiCr2O4 protective oxide scales.

关键词： nickel-based superalloy dissimilar welding weldment corrosion high-velocity oxy-fuel coating corrosion kinetics

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吸附剂细粉增强气液两相传质(Ⅱ)实验

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化工学报 1999年第6期50卷 772-777页

作者：成弘周明张缨许春建余国琮天津大学化学工程研究所天津300072

在鼓泡塔内,蒸馏条件下,实验研究了吸附剂细粉（小于10μm）对气液两相传质的影响。所用的吸附剂为4A和13X分子筛。实验发现在固含率ε_m不高于10%且对较低沸点组分有强烈吸附作用的吸附剂颗粒可以强化气液两相传质,提出了吸剂细粉强化... 详细信息

在鼓泡塔内,蒸馏条件下,实验研究了吸附剂细粉（小于10μm）对气液两相传质的影响。所用的吸附剂为4A和13X分子筛。实验发现在固含率ε_m不高于10%且对较低沸点组分有强烈吸附作用的吸附剂颗粒可以强化气液两相传质,提出了吸剂细粉强化传质的机理。根据渗透理论和对吸附等温线的线性化处理,导出相应的数学的模型,模型计算值与实验结果比较吻合。

关键词：吸附剂细粉鼓泡塔气液传质气液两相

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Comparison of Bishop score and cervical length measurement through transvaginal ultrasound as prediction against labor induction

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Asian pacific Journal of Reproduction 2018年第6期7卷 280-284页

作者： Finianty Raynelda Efendi Lukas Sriwijaya Qadar Maisuri t Chalid Department of Obstetrics and Gynecology Faculty of MedicineUniversity of HasanuddinMakassarIndonesia Wahidin Sudirohusodi Hospital MakassarIndonesia

Objective:to compare the Bishop score and cervical length measured by transvaginal ultrasound concerned with prediction over the success of labor ***:this cross-sectional observational analytical study was conducted from May 2017 to October 2017 at several teaching hospitals of Obstetrics and Gynecology Department, Faculty of Medicine Hasanuddin University of Makassar, India. there were 110 samples of pregnant women undergoing labor induction process including 79 samples of successful induction and 31 samples of induction failure. the data analysis used Pearson Chi-square test and multivariate logistic regression to see the effect of Bishop score and measurement of cervical length with successful induction of ***: Number of samples with successful labor induction with Bishop score th rate ratio=3.714 andP=0.000. With measurement of cervical length (cut-off point 2.98 cm), number of samples with successful labor induction with cervical length≤2.98 cm was 12 (15.2%) and cervical length >2.98 cm was 67 (84.8%), with rate ratio=3.124 andP=0.000. Multivahate analysis of logistic regression was found to be more influential in the predicted success of labor induction (P=0.014 with Bishop score tio=1.000 and Bishop score≥3, odds ratio=3.779. Conclusions: Bishop score is better in predicting the success of labor induction compared to the measurement of cervical length through transvaginal ultrasound.

关键词： Bishop score Cervical length Labor induction transvaginal ultrasound

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Gradient Structured Copper by Rotationally Accelerated Shot Peening

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Journal of Materials Science & technology 2017年第7期33卷 758-761页

作者： X.Wang Y.S.Li Q.Z.ang Y.H.Zhao Y.t.Zhu Nano Structural Materials Center School of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China Department of Materials Science and Engineering North Carolina State University Raleigh NC 27695 USA

A new technology-rotationally accelerated shot peening（RASP）, was developed to prepare gradient structured materials. By using centrifugal acceleration principle and large steel balls, the RASP technology can produce much higher impact energy compared to conventional shot peening. As a proof-of-concept demonstration, the RASP was utilized to refine the surface layer in pure copper（Cu） with an average grain size of 85 nm. the grain size increases largely from surface downwards the bulk, forming an800 ？m thick gradient-structured surface layer and consequently a micro-hardness gradient. the difference between the RASP technology and other established techniques in preparing gradient structured materials is discussed. the RASP technology exhibits a promoting future for large-scale manufacturing of gradient materials.

关键词： Microstructure Rotationally accelerated shot peening Gradient structure Hardness Copper

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Single and Multicasting Inverted-Wavelength Conversion at 80 Gb/s Based on a Single Semiconductor Optical Amplifier

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Chinese Physics Letters 2011年第11期28卷 138-140页

作者： HUANG Xi QIN Cui yu yu ZHANG Xin-Liang Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074

We experimentally demonstrate single and multicasting inverted wavelength conversion at 80 Gb/s by using the cross-gain modulation and cross-phase modulation in a single semiconductor optical amplifier(SOA).In all the cases,converted signals with a high extinction ratio(ER)and large eye opening are *** singlechannel wavelength conversion,the ER of the output signal is as high as 30.10 *** three-channel wavelength multicasting,high quality converted signals could also be *** ERs with three channels are 21.54 dB,18.58 dB and 17.72 dB,***,one-and three-channel wavelength conversion with high performance can be achieved by using a single quantum-well SOA.

关键词： Gb/s amplifier channel

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Plant diversity in a changing world: status,trends,and conservation needs

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植物分类与资源学报 2016年第1期38卷 11-18页

作者： Richard t.Corlett Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of Sciences

the conservation of plants has not generated the sense of urgency—or the funding—that drives the conservation of animals,although plants are far more important for us. there are an estimated 500,000 species of land plants( angiosperms,gymnosperms,ferns,lycophytes,and bryophytes),with diversity strongly concentrated in the humid tropics. Many species are still unknown to science. Perhaps a third of all land plants are at risk of extinction,including many that are undescribed,or are described but otherwise data deficient. there have been few known global extinctions so far,but many additional species have not been recorded recently and may be extinct. Although only a minority of plant species have a specific human use,many more play important roles in natural ecosystems and the services they provide,and rare species are more likely to have unusual traits that could be useful in the future. the major threats to plant diversity include habitat loss,fragmentation,and degradation,overexploitation,invasive species,pollution,and anthropogenic climate change. Conservation of plant diversity is a massive task if viewed globally,but the combination of a well-designed and well-managed protected area system and ex situ gap-filling and back-up should work anywhere. the most urgent needs are for the completion of the global botanical inventory and an assessment of the conservation status of the 94% of plant species not yet evaluated,so that both in and ex situ conservation can be targeted ***,the biggest conservation gap is in the hyperdiverse lowland tropics and this is where attention needs to be focused.

关键词：植物学植物分类植物生态学植物演化

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three-dimensional cytoplasmic calcium propagation with boundaries

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Communications in theoretical Physics 2021年第1期73卷 87-98页

作者： Han-yu Jiang Jun He Department of Physics and Institute of theoretical Physics Nanjing Normal UniversityNanjing210097China Sino-U.S.Center for Grazingland Ecosystem Sustainability/Pratacultural Engineering Laboratory of Gansu Province/Key Laboratory of Grassland Ecosystem Ministry of Education/College of Pratacultural ScienceGansu Agricultural UniversityLanzhou730070China

Ca^(2+)plays an important role in cell signal *** intracellular propagation is the most basic process of Ca^(2+)signaling,such as calcium wave and double messenger *** this work,with both numerical simulation and mean field ansatz,the three-dimensional probability distribution of Ca^(2+),which is read out by phosphorylation,is studied in two scenarios with *** coverage of distribution of Ca^(2+)is found at an order of magnitude ofμm,which is consistent with experimental observed calcium spike and *** results suggest that the double messenger system may occur in the ER-PM junction to acquire great *** buffer effect of kinase is also discussed by calculating the average position of phosphorylations and free Ca^(2+).the results are helpful to understand the mechanism of Ca^(2+)signaling.

关键词： Ca^(2+)signaling diffusion Gillespie algorithm mean field ansatz

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A Kinetic Study of Ozone and Nitric Oxides in Dielectric Barrier Discharges for O_2/NO_x Mixtures

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Plasma Science and technology 2002年第2期4卷 1227-1238页

作者：孙继忠 Stirner t 王德真 Department of Chemistry University of Hull HU6 7RX UK the State Key Laboratory of Material Modification by Laser Ion and Electron Beams Department of Physics Dalian University of Technology Dalian 116024 China

A simple model is described to simulate kinetic processes in dielectric barrier dis-charges for O2/NOx mixtures. A threshold of ozone production found experimentally is confirmedby the calculations of this modeling, and the underiying chemical reaction mechanisms are dis-cussed. It is also found that the effects of diffusion processes in the period of the lifetime of Oatoms are not important to microdischarge channels with a large radius, i.e. larger than l50 μm.

关键词： A Kinetic Study of Ozone and Nitric Oxides in Dielectric Barrier Discharges for O2/NOx Mixtures NO

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Additions of landscape metrics improve predictions of occurrence of species distribution models

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Journal of Forestry Research 2017年第5期28卷 963-974页

作者： rica Hasui Vinícius X.Silva Rogrio G.t.Cunha Flavio N.Ramos Milton C.Ribeiro Mario Sacramento Marco t.P.Coelho Diego G.S.Pereira Bruno R.Ribeiro Laboratório de Ecologia de Fragmentos Florestais(ECOFRAG) Instituto de Ciência da NaturezaUniversidade Federal de Alfenas Laboratório de Ecologia Espacial e Conservao(LEEC) Departamento de EcologiaUNESP Estao de Hidrobiologia e Piscicultura de Furnas–EHPF Programa de Pós-Graduao em Ecologia e Evoluo da Universidade Federal de Goiás Universidade Federal de Goiás Departamento de Ciências Florestais Universidade Federal de LavrasCmpus Universitário

Species distribution models are used to aid our understanding of the processes driving the spatial patterns of species’ habitats. this approach has received criticism, however, largely because it neglects landscape metrics. We examined the relative impacts of landscape predictors on the accuracy of habitat models by constructing distribution models at regional scales incorporating environmental variables (climate, topography, vegetation, and soil types) and secondary species occurrence data, and using them to predict the occurrence of 36 species in 15 forest fragments where we conducted rapid surveys. We then selected six landscape predictors at the landscape scale and ran general linear models of species presence/absence with either a single scale predictor (the probabilities of occurrence of the distribution models or landscape variables) or multiple scale predictors (distribution models + one landscape variable). Our results indicated that distribution models alone had poor predictive abilities but were improved when landscape predictors were added; the species responses were not, however, similar to the multiple scale predictors. Our study thus highlights the importance of considering landscape metrics to generate more accurate habitat suitability models.

关键词： Ecological niche model Generalized linear models Habitat suitability Landscape structure Maxent

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Hypolipidaemic and antioxidant effect of Enicostemma littorale Blume

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Asian Pacific Journal of tropical Biomedicine 2011年第5期1卷 381-385页

作者： thirumalai t Viviyan therasa S Elumalai EK David E Post Graduate and Research Department of Zoology Voorhees CollegePhysiology Wing

Objective:to investigate the hypolipidaemic and antioxidant effects of aqueous leaf extract of Enicoslemma littorale(***)Blume(Ens)against ethanol induced hepatic injury in albino ***:Male albino rats of six numbers in each group were undertaken for *** and antioxidant effect of *** Blume(Ens)aqueous leaf extract at a dosage of 250 mg/kg bw was ***:Levels of serum and tissue cholesterol,triglycerides and free fatty acids were elevated and levels of tissue thiobarbituric acid reactive substances(tBARS)and lipid hydroperoxide were increased in ethanol treated *** activity levels of liver antioxidant enzymes such as superoxide dismutase(SOD),catalase(CAt),glutathione peroxidase(GPX)and glutathione-s-transferase(GSt)were *** adiminstration of extract of E,littorale Blume,levels of cholesterol,triglycerides and free fatty acids were decreased in serum and liver tissue,levels of tBARS and lipid hydroperoxide were decreased,and Ever antioxidant enzymes were increased in liver tissue;Conclusions:It can be concluded that the aqueous leaf extract of E,littorale Blume(Ens)has potent restorative effect on hyperlipidaemic and oxidative stress.

关键词： Hepatoprotective Ethanol Antioxidant enzymes Enicostemma littorale Blume Oxidative stress Hypolipidaemic effect

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