Particle Size Distribution,Powder Agglomerates and Their Effects on Sinterability of Ultrafine Alumina Powders

An intensive study of the particle size distribution of four commercial ultrafine alumina powders to obtain information about the powder agglomeration and relate them to the compactibility and the sinterability has been made.

Vibration analysis of fluid-conveying multi-scale hybrid nanocomposite shells with respect to agglomeration of nanofillers

The vibration problem of a fluid conveying cylindrical shell consisted of newly developed multi-scale hybrid nanocomposites is solved in the present manuscript within the framework of an analytical solution.The consistent material is considered to be made from an initial matrix strengthened via both macro-and nano-scale reinforcements.The influence of nanofillers’agglomeration,generated due to the high surface to volume ratio in nanostructures,is included by implementing Eshelby-Mori-Tanaka homogenization scheme.Afterwards,the equivalent material properties of the carbon nanotube reinforced(CNTR)nanocomposite are coupled with those of CFs within the framework of a modified rule of mixture.On the other hand,the influences of viscous flow are covered by extending the Navier-Stokes equation for cylinders.A cylindrical coordinate system is chosen and mixed with the infinitesimal strains of first-order shear deformation theory of shells to obtain the motion equations on the basis of the dynamic form of principle of virtual work.Next,the achieved governing equations will be solved by Galerkin’s method to reach the natural frequency of the structure for both simply supported and clamped boundary conditions.Presenting a set of illustrations,effects of each parameter on the dimensionless frequency of nanocomposite shells will be shown graphically.

Agglomeration and Employment Density:Test Based on Panel Data of Prefecture-Level Cities of China

Related factors for measuring urban agglomeration effect were studied firstly.Then,panel data of 283 prefecture level cities of China were collected to analyze the effect of agglomeration on employment density.Besides,fixed effect model was applied to analyze static panel data,and two-step generalized method of moments(GMM) estimator was employed to analyze dynamic panel data.Results reveal that per capita regional GDP,public medical care level,and population mobility have significant effect on employment density.Therefore,there exists effect of agglomeration economy in prefecture level cities of China in the current stage.

Fiscal Pressure, Inter-Industrial Allocation of Land and Agglomerations Effects

Land is a production factor that supports industrial development and also an important resource for increasing local government revenue.The scientific allocation of land has a positive effect on applying a new development philosophy.Based on the data of China's micro land transaction,this paper constructs the industrial dispersion indicator of land transfer to discuss about how short-term fiscal pressure affects allocation of land resources among industries and then analyzes its impacts on agglomeration effects.The results show that the greater the short-term fiscal pressure,the higher the dispersion of land transfer among industries,which holds true after going through a series of robustness tests.Further analyses show that the dispersion of land transfer among industries deteriorates the policy orientation of giving priority to key industries.Finally,the practice of dispersion of land transfer among industries weakens agglomeration economies.The research results of this paper show that local governments'strategy of land transfer among induestries for coping with short-term fiscal pressure has the characteristics of"increasing fiscal revenues and weakening the role of industrial guidance."This means that in the new stage of development,local governments urgently need to enhance their understanding of the multiple functions of land and avoid impairing industrial development for addressing the shortterm fiscal pressure.

Spatial agglomeration and influencing factors of pulmonary tuberculosis in the Chinese mainland from 2015 to 2019

Pulmonary tuberculosis is an infectious disease caused by Mycobacterium tuberculosis,which currently has a high incidence worldwide.Based on the incidence and mortality data of tuberculosis in 31 provinces,municipalities and autonomous regions in Chinese mainland from 2015 to 2019,this paper analyzes and studies the spatial agglomeration and local accumulation effects of tuberculosis incidence in Chinese mainland.Studies show that there is an obvious seasonal trend in the transmission of tuberculosis.The incidence peaks in March each year after the bottom in February.In addition,the tuberculosis incidence shows obvious spatial agglomeration,with a relatively high incidence rate in Xinjiang,Tibet,Qinghai,Guizhou,etc.,while a low incidence rate in Beijing,Tianjin,Shanghai,Shandong,Jiangsu,Zhejiang,etc.Overall,the incidence has a clear upward trend from east to west,and the incidence rate in inland areas is higher than that in coastal areas.In addition,the paper also considers other factors that contribute to high-frequency transmissions,such as bad climate,poor air quality,and an underdeveloped economy.The most influential factor to the tuberculosis incidence is economic development level,and poor air quality in the northwest and southwest regions is also important reason for the high tuberculosis incidence.