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Propulsion and Power Research 2019年第4期8卷 339-350页

作者： M.K.Nayak J.Prakash d.Tripathi V.S.Pandey department of Physics IHSESiksha"O"Anusandhan Deemed to be UniversityBhubaneswar751003OdishaIndia department of Mathematics Avvaiyar Government College for WomenKaraikal609602Puducherry-U.T.India department of Mathematics National Institute of TechnologyUttarakhand246174India department of Physics National Institute of Technology DelhiNew DelhiIndia

A numerical simulation is presented to investigate the effect of an exponentially varying magnetic field on three dimensional flow of Zinc Oxide-Society of Automotive Engineers 50 nanolubricant(ZnO-SAE50nano-lubricant)past a stretching *** the impact of homogenous and heterogeneous reactions on the flow of nanolubricant concerned has also taken into *** study has been strengthened by introducing the convection mechanism and the effect of thermal *** transformations are employed to transform the set of partial governing equations into the set of ordinary differential *** suitable boundary conditions are used to obtain the numerical *** numerical results are simulated using Matlab bvp4c solver and validated with the existing *** flow characteristics,thermal characteristics,nanoparticle concentration and some non-dimensional numbers are computed under the influence of the pertinent *** valuable outcome of the current study is that augmented magnetic field strength is the root cause of diminishing axial as well as transverse velocities and growing trend of fluid ***,the coeffi-cients of homogenous and heterogeneous reactions are boons for ascending concentration boundary layer.

关键词： MHd 3d flow ZnO-SAE50nanolubricant Exponential stretching sheet Convective heating mechanism Thermal radiation Heat generation/absorption

Crustal P-and S-Wave Velocity Structure of the North China Craton at 36°N from Active-Source Seismic data and Its Tectonic Implications

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Journal of Earth Science 2022年第3期33卷 642-663页

作者： Xiaofeng Tian Walter dMooney Xiaoguo deng Songlin Li Baofeng Liu Hanqi Liu Geophysical Exploration Center China Earthquake AdministrationZhengzhou 450003China U.S.Geological Survey Menlo Park CA94025USA

We present crustal models for seismic P-waves(Vp),S-waves(Vs)and the Vp/Vs ratio across the southern North China Craton along latitude 36°*** results are based on inverse and forward modeling of long-range wide-angle reflection/refraction *** crust of the southern Ordos Block has high lower crustal velocity(7.0 km/s)and a Moho depth of~42 *** contrast,thick sediments and a lower average velocity(compared with the Ordos block)found underneath the Shanxi Graben are likely to be the products of rifting that has occurred since the *** Moho dips,exposed basement rock and higher average crustal velocity beneath the Lüliang Mountain and the Taihang Mountain are characteristic of an orogenic *** Tanlu fault and the Liaocheng-Lankao fault show sharp crustal velocity variations and a Moho *** seismic profile sampled the entire region of the Eastern North China Craton where the cratonic root has been destroyed and the unique crustal structure is correlated with the substantially modified *** crustal seismic velocity model shows a strong correspondence between surface geology,local tectonics and the deep crustal structure.

关键词： North China Craton crustal velocity structure craton destructure tectonics wideangle reflection/refraction

全层状TiAl基合金拉伸试验断裂过程及机理

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机械工程学报 2008年第1期44卷 40-45页

作者：曹睿林有智陈剑虹 HU d 兰州理工大学甘肃省有色金属新材料重点实验室兰州730050 宁德职业技术学院福安355000 伯明翰大学跨学科材料研究中心英国伯明翰B152TT

通过对全层组织TiAl基合金不同缺口试样进行原位拉伸试验,结合数据分析以及断口形貌的观察,研究TiAl基合金拉伸的断裂过程和断裂机理。研究发现在原位拉伸试验中,对于直缺口试样,裂纹起裂于缺口根部,其断裂过程主要是主裂纹(沿层裂纹)... 详细信息

通过对全层组织TiAl基合金不同缺口试样进行原位拉伸试验,结合数据分析以及断口形貌的观察,研究TiAl基合金拉伸的断裂过程和断裂机理。研究发现在原位拉伸试验中,对于直缺口试样,裂纹起裂于缺口根部,其断裂过程主要是主裂纹(沿层裂纹)首先起裂、扩展、连接,然后形成解理断裂起裂源。这一起裂源形成的同时,在刚好能满足Griffiths脆性解理断裂所需要的临界裂纹尺寸时,引起整个试件发生脆性解理断裂。裂纹首先起裂于层间,层间是薄弱环节,断裂方式是穿层断裂和沿层断裂的混合体,以穿层断裂为主。对于大圆弧和平板试样,这种材料的断裂过程是:首先在较高外加载荷下,在标距范围内比较薄弱的区域沿层开裂,随着外加载荷的进一步增加,这些微裂纹扩展,当微裂纹引起的应力集中和外加载荷共同作用足以引起微裂纹进一步贯穿的瞬间,即能量积累到一定程度时,试样整体发生解理断裂。很多试样的断裂是直接起裂的过程,一旦产生裂纹试样立即解理断裂,即这种材料的强度较高,材料很难产生裂纹,也不易损伤。

关键词： TiAl基合金原位拉伸断裂机理

Method for detecting soil total nitrogen contents based on pyrolysis and artificial olfaction

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International Journal of Agricultural and Biological Engineering 2022年第3期15卷 167-176页

作者： Mingwei Li Qinghui Zhu He Liu Xiaomeng Xia dongyan Huang School of Biological and Agricultural Engineering Jilin UniversityChangchun 130022China Key Laboratory of Bionic Engineering Ministry of EducationJilin UniversityChangchun 130022China

Soil nitrogen is an essential nutrient element for crop growth and development,and an important indicator of soil fertility *** study proposed a method based on pyrolysis and artificial olfaction to quickly and accurately determine the soil total nitrogen(STN)content.A muffle furnace was used to pyrolyze the soil samples,and ten different types of oxide semiconductor gas sensors were used to construct a sensor array to detect the soil samples’pyrolysis *** response curves of the sensors were tested at pyrolysis temperatures of 200℃,300℃,400℃,and 500℃ and at pyrolysis times of 1 min,3 min,5 min,and 10 min to obtain the optimal pyrolysis state of the soil *** optimal pyrolysis temperature was 400℃,and the pyrolysis time was 3 *** response area,maximum value,average differential coefficient,variance value,maximum gradient value,average value,and 8th-second transient value of the sensor response curve were extracted to construct an artificial olfactory feature space of 121×10×7(121 soil samples,ten sensor numbers,seven extracted eigenvalues).Back-propagation neural network algorithm(BPNN),partial least squares regression algorithm(PLSR),and partial least squares regression combined with back-propagation neural network algorithm(PLSR-BPNN)were used to establish a prediction model of artificial olfactory feature space and STN ***,coefficient of determination(R2),root mean square error(RMSE),and the ratio of performance to deviation(RPd)were used as the performance indicators of the prediction *** test results showed that the R2 of the PLSR,BPNN,and PLSR-BPNN models were 0.89033,0.81185,and 0.92186,and the RMSE values were 0.24297,0.37370,and 0.21781,and the RPd were 2.9964,1.9482,and 3.3426,*** model established by the PLSR-BPNN algorithm has the highest R2 and RPd and the smallest RMSE,can achieve the accurate prediction of STN content,and therefore the model is rated as“excellent”.The detection method in

关键词： pyrolysis artificial olfactory system soil total nitrogen gas sensor array prediction methods

Effect of Withania somnifera root extract on the sexual behaviour of male rats

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Asian Journal of Andrology 2002年第4期4卷 295-297页

作者： I. Ilayperuma W.d. Ratnasooriya T.R. Weerasooriya department of Anatomy Faculty of Medicine University of Ruhuna Sri LankaDepartment of Zoology Faculty of Science University of Colombo Sri LankaDepartment of Anatomy Faculty of Medicine University of Ruhuna Sri Lanka

Aim: To determine the effect of a methanolic extract of Withania somnifera (L.) dunal roots on sexual competence of male rats. Methods: Male rats were orally administered 3000 mg'kg^***^1 of root extract for 7 days. Their sexual behaviour was evaluated 7 days prior to treatment, day 3 and 7 of treatment, and day 7, 14 and 30 posttreatment by pairing each male with a receptive female. Results: The root extract induced a marked impairment in libido, sexual performance, sexual vigour, and penile erectile dysfunction. These effects were partly reversible on cessation of treatment. These antimasculine effects are not due to changes in testosterone levels or toxicity but may be attributed to hyperprolactinemic, GABAergic, serotonergic or sedative activities of the extract. Conclusion: Use of W. somnifera roots may be detrimental to male sexual competence. (Asian J Androl 2002 dec;4: 295-298)

关键词： Withania somnifera male sexual competence aphrodiasiac libido antimasculine male sexual behaviour

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TiAl基合金弯曲疲劳的断裂机制

稀有金属材料与工程 2009年第4期38卷 637-641页

作者：曹睿林有智陈剑虹 Hu．d 兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室甘肃兰州730050 Interdisciplinary Research Central University of Birmingham Birmingham B15 2TT UK

通过对弯曲疲劳断裂宏观试验结果以及相应的卸载表面观察和断口观察分析研究,发现在疲劳加载的过程中,首先在缺口根部产生裂纹,裂纹在应力循环的作用下不断扩展,直至疲劳裂纹的长度达到与疲劳外加力所匹配的临界裂纹长度时,突然发生整... 详细信息

通过对弯曲疲劳断裂宏观试验结果以及相应的卸载表面观察和断口观察分析研究,发现在疲劳加载的过程中,首先在缺口根部产生裂纹,裂纹在应力循环的作用下不断扩展,直至疲劳裂纹的长度达到与疲劳外加力所匹配的临界裂纹长度时,突然发生整体解理断裂。在一定应力下的疲劳弯曲加载试验中,随着循环次数的增加,产生的裂纹变长,即产生的损伤严重,疲劳区域变宽,其断裂机制是疲劳区各裂纹单向扩展,解理区起裂源分散扩展直至断裂。对于循环次数较小的材料,其断裂机制是具有发散扩展路径的起裂源直接产生于缺口根部,然后分散扩展直至断裂,在其扩展的路径上并不因疲劳区与解理区而有任何的不同。

关键词： TiAl合金弯曲疲劳断裂机制

Retinal image quality with multifocal,EdoF,and accommodative intraocular lenses as studied by pyramidal aberrometry

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Eye and Vision 2021年第6期8卷 374-384页

作者： Jorge L.Alio Francesco d’Oria Francesca Toto Joan Balgos Antonio Palazon Francesco Versaci Jorge L.Alio del Barrio Vissum Innovation AlicanteSpain division of Ophthalmology Universidad Miguel HernándezVissum Miranzac/Cabañal103016 AlicanteSpain Section of Ophthalmology Department of Basic Medical ScienceNeuroscience and Sense OrgansUniversity of BariBariItaly department of Clinical Medicine Miguel Hernández UniversitySan Juan de AlicanteSpain R&d department Costruzione Strumenti Oftalmici(CSO)FlorenceItaly

Background:To study and compare the clinical optical image quality following implantation with different premium IOLs by analysing the point spread function(PSF)Strehl ratio using a pyramidal wavefront sensor(PWS)-based ***:This study included 194 eyes implanted with:(a)19 AcrySof SA60AT(control group);(b)19 Miniwell;(c)24 LENTIS Mplus LS-313 MF30;(d)33 LENTIS Mplus LS-313 MF15;(e)17 AkkoLens Lumina;(f)31 AT LISA Tri 839MP;(g)20 Precizon Presbyopic;(h)20 AcrySof IQ PanOptix;(i)11 Tecnis *** outcome measures were PSF Strehl ratio,PSF Strehl ratio excluding second-order aberrations(PSFw2),total root mean square(RMS),low-order aberration(LOA)and high-order aberration(HOA)RMS measured by PWS ***:AT LISA Tri had the highest PSFw2 Strehl ratio at both 3.0-and 4.0-mm pupil size(0.52±0.14 and 0.31±0.10;Pd by SA60AT(0.41±0.11 and 0.28±0.07)and PanOptix(0.4±0.07 and 0.26±0.04).AT LISA Tri was found to provide a significantly better retinal image quality than PanOptix at both 3.0 mm(Pd 4.0 mm(P=0.004).Mplus MF15 was found to be significantly better than Mplus MF30 at both 3.0 mm(Pd 4.0 mm(P=0.002).Total RMS,LOA RMS,HOA RMS,PSF Strehl ratio and PSFw2 varied significantly between the studied groups(Pdistance clinical image quality parameters measured by PWS aberrometer differed significantly according to the technology of the implanted *** LISA Tri,SA60AT and PanOptix showed the highest values of far distance retinal image quality,while the lowest PSFw2 Strehl ratios were displayed by Miniwell,Mplus MF30 and Precizon Presbyopic.

关键词： Cataract surgery Pyramidal aberrometry Multifocal IOL Extended depth of focus Accommodative IOL

China under Uncertainty： Outlook, Counterfactual and Policy Simulations, and Reform Implementation--A Summary of Annual Report （2016-2017）

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2017年第2期12卷 167-187页

作者： Kevin X. d. Huang Guoqiang Tian Yibo Yang department of Economics Vanderbilt University Nashville TN 37235 USA Institute for Advanced Research Shanghai University of Finance and Economics Shanghai 200433 China School of Economics and Institute for Advanced Research Shanghai University of Finance and Economics Shanghai 200433 China department of Economics Texas A&M University College Station TX 77843-1372 USA

China＇s macroeconomy is surrounded by increased uncertainties while facing persistent downward pressures entering year 2017. Major external challenges are imposed by the chaotic political climate and disorderly retreat from globalization of the US accompanied with the impending FEd rate hikes, which may trigger a destructive trade war and exert pressures on RMB depreciation and capital flight. Remaining ingrained in major internal challenges are the gridlock risks accumulated from excessive financialization of real estate sector and swelling housing market bubbles amid escalating debt levels, and more fundamentally, the continued off-real-to-virtual movement in the general economy and ascendancy of government over market in resource *** on IAR-CMM model, which takes into account both cyclical and secular factors, the baseline real GdP growth rate is projected to be 6.5% in 2017 （6.13% using more reliable instead of official data）. Counterfactual analyses and policy simulations are also conducted to highlight the convoluted uncertainties surrounding China＇s macroeconomy. Through the lens of these analyses, we identify a root cause of the weak outlook as the persistently distorted economic structure due to procrastination in reforms of the institutions and governance, which not only impairs China＇s growth potential but also limits the power of its recent stimulating policies while exacerbating their side effects. Key to successful economic restructuring in the face of adversely evolving demographics are market-oriented reforms, with well-designed strategies to balance short-term stabilization and long-run development. Such reforms should hold center stage in China＇s transition towards a modern free market economy and regulatory state.

关键词： macroeconomic outlook uncertainty alternative scenarios policysimulation reform development governance

root Secretion of Phytochemicals in Arabidopsis Is Predominantly Not Influenced by diurnal Rhythms

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Molecular Plant 2010年第3期3卷 491-498页

作者： dayakar V. Badri Victor M. Loyola-Vargas Corey d. Broeckling Jorge M. Vivanco Center for Rhizosphere Biology Colorado State University Fort Collins CO 80523 USA 30 Col. Chuburna de Hidalgo Merida Yucatan Mexico

root-secreted phytochemicals mediate multiple interactions in the rhizosphere. The root exudation process can be altered by various biotic factors, including pathogenic and non-pathogenic microbes, and abiotic factors like temperature and soil moisture. It has been suggested that root secretion of specific flavonoids is influenced by diurnal rhythms （by light or dark） but a comprehensive analysis of the overall secretion of phytochemicals in response to diurnal rhythms has not been studied. In this study, we analyzed the effect of light/dark cycles on root exudation profiles using Arabidopsis as a model plant. Our results reveal that the root secretion of phytochemicals is partly regulated by the diurnal light cycle and follows two main patterns of secretion：（1） the large majority of phytochemicals in the exudates showed no diurnal pattern in their secretion, and （2） a few compounds showed a diurnal pattern in their secretion： three compounds increased in secretion only under light; two compounds increased in secretion only while it was dark; and two compounds increased in secretion during the transition from dark to light. root-specific ABC transporters have been implicated in root exudation; an analysis of the gene expression patterns of ABC transporters in the roots of Arabidopsis at specific time points revealed that none of the ABC transporters followed a diurnal expression pattern, suggesting that they are expressed constantly during the day and night. Similarly, we analyzed the expression in roots of genes involved in secondary metabolite biosynthesis and found that some of the genes involved in phenylpropanoid and glucosinolate biosynthesis （i.e. 4-coumarate-CoA ligases （4CL1 and 4CL2）, flavonol synthases （FSl and FS2）, and CYP79B3） followed distinct diurnal expression patterns. Overall, we have discovered that while root exudation of the majority of phytochemicals is constitutive, the secretion of a few compounds follows a diurnal rhythm, which is in accor

关键词： Arabidopsis diurnal rhythm root exudates ABC transporters secondary metabolite biosynthesis.

Investigation of structure and mechanical properties of plasma vapor deposited nanocomposite TiBN films

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Plasma Science and Technology 2017年第4期19卷 76-84页

作者：韩滨 d NEENA 王泽松 K K KONdAMAREddY 李娜左文彬闫少健刘传胜付德君 School of Physics and Technology and Key Laboratory of Artificial Micro-and Nano-Materials of Ministry of Education Hubei Nuclear Solid Physics Key Laboratory Wuhan University Wuhan 430072 People's Republic of China

TiBN coatings have huge potential applications as they have excellent properties with increasing modem industrial *** TiBN coatings were synthesized on cemented carbide,high speed steel and Si substrates by using cathodic arc plasma ion plating from pure TiB2 ceramic *** structure and mechanical properties of the TiBN coatings were significantly influenced by the nitrogen partial *** backscattering spectrometry demonstrates that the nitrogen content of the coating varied from 2.8% to 34.5% and highresolution electron microscopy images reveal that all coatings have the characteristic of nanocrystals embedded in an amorphous *** root-mean-square roughness of the coatings increases from 3.73 to 14.64 nm and the coefficients of friction of the coatings at room temperature vary from 0.54 to 0.73 with increasing nitrogen partial *** microhardness of the coating increases up to 35.7 GPa at 10 sccm N2 flow *** smallest wear rate is 2.65 ×10^-15m^3N^-1m^-1 which indicates that TiBN coatings have excellent wear *** adhesion test revealed that the TiBN coatings have good adhesion at low nitrogen partial pressure.

关键词： TiBN nanocomposite RBS tribological properties HRTEM