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Bubbly shock propagation as a mechanism of shedding in separated cavitating flows

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Journal of hydrodynamics 2017年第6期29卷 907-916页

作者： harish Ganesh Simo A.Makiharju Steven l.Ceccio University of Michigan Ann ArborUSA University of California BerkeleyUSA

Stable attached partial cavitation in separated flows can transition to cloud shedding, and the mechanism of transition has been attributed to the presence of a re-entrant liquid jet. Our findings have revealed the presence of propagating bubbly shock waves as an alternative dominant mechanism of shedding when the compressibility of the bubbly mixture is appreciable. In the present paper, we discuss dynamics associated with these bubbly shock waves, interaction of shock waves with obstacles in their path, and means to manipulate their properties to control the shedding process by non-condensable gas injection.

关键词： Partial cavitation bubbly shock waves cloud cavitation X-ray densitometry

nutritional Status, Food Consumption at home, and Preference-Selection in the School

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Food and nutrition Sciences 2012年第3期3卷 281-285页

作者： María del Refugio lópez-Gamino Martha Elba Alarcón-Armendáriz Xochitl Karina Torres-Beltrán Educación para la Salud FES IztacalaUniversidad Nacional Autónoma de MéxicoMéxico CityMéxico.

To assess the relationship between food consumption at home, nutritional status, gender preference and the preference-selection of natural products (fruits and vegetables) and industrialized (candies and chips) in a situation of free access for a population of Mexican schoolchildren. 115 children participated in the test, 59 boys and 56 girls from second, fourth and sixth grade of elementary school. We have taken measures of weight, size and the 24-hour consumption record during over five days, at which time also we evaluated the preference and selection of a group of ten products (naturals and industrialized). According to the results 60% of children had normal weight, 23.47% overweight, 14.8% risk of overweight an 1.73% underweight. There were no significant differences with X2 test between nutritional status and gender. Multivariate analysis was applied between gender, consumption by food groups and nutritional status, the interaction was significant in all cases. The Pearson correlation between preference and food choice in the situation of open access is high in the school students at risk of overweight. The preferred and selected products for consumption are those with the highest content of saturated fat, sugars and salt, the less preferred and selected products were fruits and vegetables. We could conclude that the population is at risk for their low consumption of fruits and vegetables;situation that is reflection of the home consumption this document.

关键词： Food Preferences Diet Schoolchild nutritional Status

hydrothermal Synthesis and Crystal Structure of a Bivanadyl Capped Keggin Polyoxomet alate[Zn(2,2'-bpy)_2(h_2O)]_2[hPMo_(12)O_(40)(VO)_2]

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Chinese Journal of Structural Chemistry 2005年第2期24卷 139-144页

作者： lüXiu-Qing ChEnJian-Xin lAnTing-Yan hUAnGYuan-Biao （CollegeofChemistryandMaterialsScience FujianNormalUniversityFuzhouFujian350007China

A hydrothermal reaction of zinc acetate with molybdenum trioxide, vanadium pentoxide, phosphorus pentoxide and 2,2?-bpy (2,2?-bipyridine) led to the title compound [Zn(2,2?- bpy)2(h2O)]2[hPMo12O40(VO)2] 1. Single-crystal X-ray diffraction revealed that 1 (C40h36- n8O44PV2Zn2Mo12) crystallizes in the triclinic system, space group P1 with a = 11.881(2), b = 12.468(2), c = 12.622(2) ?, α = 71.333(8), β = 74.485(4), γ = 86.896(5)o, V = 1705.8(4) ?3, Mr = 2747.64, Z = 1, Dc = 2.675 g/cm3, μ = 3.201 mm-1, F(000) = 1309, S = 1.070, the final R = 0.0697 and wR = 0.1905 for 5368 observed reflections with I > 2σ(I). Compound 1 is built on a mixed-metal bicapped [hPMo12V2O42] subunit covalently bonded to two [Zn(2,2?-bpy)2(h2O)]2+ clusters via terminal oxygen atoms of the capping V atoms. Each Zn atom is six-coordinated by four nitrogen atoms from two 2,2?-bpy ligands, one terminal oxygen atom from coordinated water mole- cule and another one from the capped {VO} unit.

关键词： Polyoxometalate crystal structure bivanadyl-capped polyoxoanion

A contribution to the integrated pest management of the aphid nasonovia ribisnigri in salad crops

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A contribution to the integrated pest management of the aphi...

Two-Dimensional Fluid Simulation of Collisional Plasma Sheath over rf Powered Electrode with Cylindrical hole

The Meeting of Integrated Control in Field Vegetable Crops

作者： C.Martin l.Schoen C,Rufingier n.Pasteur Agriphyto 19 avenue de Grande Bretagne66025 PerpignanFrance Institut des Sciences de l’Evolution Universite de Montpellier Ⅱ(CC065)34095 Montpellier 05France

＜正＞nasonovia ribisnigri Mosley（homoptera:Aphidae） is one of the major pests of salad crops（lactuca sativa and Cichorium endivia var. latifolia） in France and in many other European *** results following the application of registered insecticides prompted us（a） to investigate whether this aphid was becoming resistant to the commonly used insecticides,and（b） to test the efficacy of a new aphicide that could be applied at sowing to salad plants grown in peat *** results showed that a population of *** from Perpignan had developed resistance to pirimicarb,deltamethrin and endosulfan,and that a single application of imidacloprid（a chloronicotinyle insecticide） prevented aphid infestations establishing on salad *** with the insecticide lasted from the nursery bed to harvest,which in the current tests spanned a period of 56 days.

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Plasma Science and Technology 2004年第4期6卷 2404-2410页

作者：侯璐景王友年 Z.l.Miskvic State Key lab of Materials Modification by Beams Department of PhysicsDalian University of TechnologyDalian 116023China Department of Applied Mathematics University of WaterlooWaterlooOntarioCanada N2L 3G1he characteristics of collisional radio-frequency (rf) sheath dynamics over an elec-trode with a cylindrical hole is simulated by means of a self-consistent model which consists of two-dimensional time-dependent fluid equations coupled with Poisson equation. In addition an equivalent-circuit model is coupled to the fluid equations in order to self-consistently determine re-lationship between the instantaneous potential at the rf-biased electrode and the sheath thickness. Two-dimensional profiles of the potential the ion fluid velocity and the distributions of the ion and electron densities within the sheath are computed under various discharge conditions such as the discharge powers and the gas pressures. The results show that the existence of the cylindrical hole on the electrode significantly affects the sheath structure and generates a potential trap in the horizontal direction which is particularly strong when the sheath thickness is comparable to the depth of the hole. Moreover it is found that the collisional effects have a significant influence on the sheath characteristics.

The characteristics of collisional radio-frequency (rf) sheath dynamics over an elec-trode with a cylindrical hole is simulated by means of a self-consistent model which consists of two-dimensional time-dependent fluid equations coupled with Poisson equation. In addition, an equivalent-circuit model is coupled to the fluid equations in order to self-consistently determine re-lationship between the instantaneous potential at the rf-biased electrode and the sheath thickness. Two-dimensional profiles of the potential, the ion fluid velocity, and the distributions of the ion and electron densities within the sheath are computed under various discharge conditions, such as the discharge powers and the gas pressures. The results show that the existence of the cylindrical hole on the electrode significantly affects the sheath structure and generates a potential trap in the horizontal direction, which is particularly strong when the sheath thickness is comparable to the depth of the hole. Moreover, it is found that the collisional effects have a significant influence on the sheath characteristics.

关键词： two-dimensional sheath numerical simulation dusty plasma

Chemically reactive and radiative von Kármán swirling flow due to a rotating disk

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Applied Mathematics and Mechanics(English Edition) 2018年第9期39卷 1295-1310页

作者： M.KhAn J.AhMED l.AhMAD Department of Mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan Department of Mathematics Shaheed Benazir Bhutto UniversitySheringal Upper Dir 18000Pakistan

A new mathematical model is presented to study the heat and mass transfer characteristics of magnetohydrodynamic(MhD) Maxwell fluid flow over a convectively heated stretchable rotating disk. To regulate the fluid temperature at the surface, a simple isothermal model of homogeneous-heterogeneous reactions is employed. The impact of nonlinear thermal radiative heat flux on thermal transport features is studied. The transformed nonlinear system of ordinary differential equations is solved numerically with an efficient method, namely, the Runge-Kutta-Felberg fourth-order and fifth-order(RKF45)integration scheme using the MAPlE software. Achieved results are validated with previous studies in an excellent way. Major outcomes reveal that the magnetic flux reduces the velocity components in the radial, angular, and axial directions, and enhances the fluid temperature. Also, the presence of radiative heat flux is to raise the temperature of fluid. Further, the strength of homogeneous-heterogeneous reactions is useful to diminish the concentration of reaction.

关键词： rotating stretchable disk magnetic field nonlinear radiative heat flux homogeneous-heterogeneous chemical reaction

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暴雨预报中Q矢量的业务分析

气象科技 1989年第5期17卷 43-47,93页

作者： R.h.Grumm A.l.Siebers 郁淑华美国国家气象中心技术发展处

1.前言美国国家气象中心(nMC)气象业务处(MOD)的气象工作者,现在在他们的工作中拥有比以往更多的产品。随着nMC于1986年7月引进VAS资料应用中心(VDUC)的资料(Mostek和Siebers,1987),大量的卫星资料常规资料以及数值模式资料可以在业务... 详细信息

1.前言美国国家气象中心(nMC)气象业务处(MOD)的气象工作者,现在在他们的工作中拥有比以往更多的产品。随着nMC于1986年7月引进VAS资料应用中心(VDUC)的资料(Mostek和Siebers,1987),大量的卫星资料常规资料以及数值模式资料可以在业务预报中应用。最近nMC的工作集中在获取和显示VDUC模式预报场上(Siebers等人,1988年),由业务模式产生的任何场都可以被获取或被显示。

关键词：暴雨预报矢量分析国家气象中心业务预报模式预报卫星资料气象工作者气象业务常规资料数值模式

Pore structure of cementitious material enhanced by graphitic nanomaterial： a critical review

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Frontiers of Structural and Civil Engineering 2018年第1期12卷 137-147页

作者： S.A. GhAhARI E. GhAFARI l. ASSI Department of Civil Engineering Purdue University USA Department of Civil and Environmental Engineering University of South Carolina USA

Carbon nano tubes （CnT） has been introduced as an efficient nanomaterial in order to improve the mechanical and durability properties of concrete. The effect of CnT on the microstructures of cementitious materials has been widely reported. This paper combines a critical review on the effect of CnT on the pore and microstructure of cement composite with a discussion on the porosity measurement of pastes containing CnT using mercury intrusion porosimetry techniques （MIP）. It was found that, surface treatment by h2SO4 and hnO3 solution forms carboxyl acid groups on CnTs＇ surfaces that lead to the improvement of reinforcement. In this scope, this review paper involves analyzing the effect of CnT on the microstructure and the pore structure of cementitious materials. The existing methods of measuring the porosity of cementitious material are reviewed, in particular, the contact angle measurement is discussed in detail in which the most effective parameters and possible errors of calculation is presented.

关键词： carbon nano tubes microstructure porosity mercury intrusion porosimetry cement composite

通过卡那霉素选择体系再生可育小麦转基因植株

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自然科学进展（国家重点实验室通讯） 2001年第5期11卷 486-491页

作者：徐子勤 D.Becker h.lrz 西北大学生物技术省重点实验室 Institut fur Allgemeine Botanik Universita HamburgHamburg D-22609Germany

使用卡那霉素作为选择剂建立起一套有效的小麦转化体系,预培养3d的未成熟胚在基因枪轰击前后进行高渗处理,轰击后于26℃、黑暗条件培养2周,然后用150mg/l硫酸卡那霉素选择培养2周,再转至含150mg/l硫酸卡那霉素的再生培养基进行光照培养... 详细信息

使用卡那霉素作为选择剂建立起一套有效的小麦转化体系,预培养3d的未成熟胚在基因枪轰击前后进行高渗处理,轰击后于26℃、黑暗条件培养2周,然后用150mg/l硫酸卡那霉素选择培养2周,再转至含150mg/l硫酸卡那霉素的再生培养基进行光照培养。再生植株在温室中长出2～3片新叶后用2.5％硫酸卡那霉素水溶液喷洒;4周内,非转化体完全白化并枯萎,而转基因植株生长正常,用水稻Actinl启动子控制nptⅡ基因,卡那霉素选择体系的平均转化频率达到2.6％,高渗处理明显促进瞬间表达效果和稳定转化频率。目前已得到23个转基因小麦株系,大多数已经产生种子。Southern分析表明这些转基因株系均整合有不同拷贝的nptⅡ基因。

关键词：卡那霉素选择预培养高渗处理可育转基因小麦基因枪