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Clear vertical variations in phytoplankton community structure are usually observed in deep-water lakes and reservoirs, which is one of the key components of water quality and ecosystem functioning. However, the vertical patterns and ecological drivers of phytoplankton communities in deep-water lakes and reservoirs are still understudied. In this study, we took Qiandao Lake, a deep-water reservoir, as an example to reveal the vertical distribution characteristics of phytoplankton communities and its influencing factors by investigating phytoplankton community structure and the associated water quality index at 12 sites across the whole lake in two seasons (spring and autumn). The results showed that the phytoplankton abundance and chlorophyll

Purpose The spherical hybrid sliding bearings (SHSBs) can be used in ultra-precision and heavy-duty machine tools. However, there is little related research for these bearings. The purpose of this study is to investigate the static characteristics and effect factors affecting SHSBs by fluid lubrication. Design/methodology/approach Based on the theories of fluid lubrication, the Reynolds equation of general Newtonian fluid is derived to obtain the steady-state lubrication equation. The system is solved by the finite difference method and the relaxation iterative method on the staggered grid to obtain the thickness and the pressure distribution of the oil film. The radial and axial load capacities of SHSBs are determined by the pressure field integration over the spherical surface. Findings The results show that the parameters such as oil supply pressure, bearing clearance, eccentricity ratio, rotating speed and orifices’ number affecting the static characteristics of bearings are significant and the cross-coupling effect exists. Originality/value The lubrication model of SHSB is established to analyze the pressure distribution with a variety of oil film thickness. The laws of oil supply pressure, bearing clearance, eccentricity ratio, rotating speed and orifices’ number on the load capacities are researched.

A new species, Neidium limuae Liu & Kociolek, is described from Limu Mountain, which is located in the middle part of the Hainan Province, China. The valves of this new species have a distinct linear outline with rostrate apices. The areolae forming the striae are externally covered by volate projections that show a reticulated design. These occluding projections may be branched, bifurcate or T-shaped. A detailed description of this new species is presented, based on light and scanning electron microscope observations. This is the first report of the genus Neidium Pfitzer from this Chinese province. A short review of research studies on Neidium in China complements this study, and a checklist of Neidium taxa previously reported from China is given.

Curcumin is an active anticancer compound in turmeric and curry. Autophagy (programmed cell death type II) is involved in the degradation and recycling of proteins and intracellular components in r...

Rural household energy consumption in China influences people's living conditions, environmental issues and economic development. So it is worthwhile to study the rural household energy consumption and its developmental propensity in rural China. In this paper, we analyse the characteristics of energy consumption and how it changes over time. Panel data regression method is used to analyse the factors which influence energy consumption, along with differences among three regions in China. The result shows that rural household energy consumption is closely related to urbanisation and historical periods of energy consumption. If there is a 1% increase in both urbanisation and energy consumption in the previous period, then current energy consumption will increase 0.74?0.92% and 0.25?0.60% respectively.