Soil fertility, fertilizer, and the maize green revolution in East Africa

This paper investigates the reasons for the low application of external fertilizers on farms in Kenya and Uganda. The analysis uses a large panel of household data with rich soil fertility data at the plot level. The authors control for maize seed selection and household effects by using a fixed-effects semi-parametric endogenous switching model. The results suggest that Kenyan maize farmers have applied inorganic fertilizer at the optimal level, corresponding to the high nitrogen-maize relative price, in one of the two survey years and also responded to the price change over time. In Uganda, even the low application of inorganic fertilizer is not profitable because of its high relative price. The authors conclude that policies that reduce the relative price of fertilizer could be effective in both countries, while the efficacy of policies based on improving farmers'knowledge about fertilizer use will be limited as long as the relative price of fertilizer remains high.Crops&Crop Management Systems,Climate Change and Agriculture,Climate Change Mitigation and Green House Gases,Fertilizers,Food Security

Development of PVE Refrigeration Lubricants for R32

A New-PVE lubricant was developed for use with R32 refrigerant. R32 has been proposed as an alternative refrigerant for R410A refrigerant, to reduce global warming. In this report, we evaluated the relationship between the New-PVE lubricant and R32 and R410A refrigerants. The evaluation items were physical properties (miscibility, solubility, mixture viscosity and volumetric resistivity) and thermal stability and lubricity. In addition, a New-PVE was also developed to improve miscibility with R32 refrigerant

Evaluation of Friction and Wear on PVE Refrigeration Lubricants for HFC Refrigerants

For the prevention of global warming, it is important for home electric appliance to improve the energy saving performance. Air-conditioner is one of home electric appliances, and the improvement of energy consumption efficiency is being performed by various ways. Lubricant for air-conditioner is used to protect sliding surfaces of a compressor. The low friction coefficient lubricant is considered to improve the friction coefficient between rotor and vane of the rotary-type compressor. We evaluated the friction and the wear on PVE refrigeration lubricants for HFC refrigerants. The friction coefficient and wear were measured by using the hermetic type block-on-ring tester. The evaluation items were physical properties (miscibility, solubility, mixture viscosity and volumetric resistivity) and thermal stability

Neutrino-driven massive stellar explosions in 3D fostered by magnetic fields via turbulent α\alpha-effect

We investigate the influence of magnetic field amplification on the core-collapse supernovae in highly magnetized progenitors through three-dimensional simulations. By considering rotating models, we observe a strong correlation between the exponential growth of the magnetic field in the gain region and the initiation of shock revival, with a faster onset compared to the non-rotating model. We highlight that the mean magnetic field experiences exponential amplification as a result of $\alpha$-effect in the dynamo process, which works efficiently with the increasing kinetic helicity of the turbulence within the gain region. Our findings indicate that the significant amplification of the mean magnetic fields leads to the development of locally intense turbulent magnetic fields, particularly in the vicinity of the poles, thereby promoting the revival of the shock by neutrino heating.Comment: 6 pages, 4 figures, submitted to MNRAS Letter

Properties of lubricants for refrigeration system with the low GWP refrigerants

For the prevention of global warming, various low GWP refrigerants (R1234yf, R1234ze, R448A, R449A, R452A, R452B, R454B etc.) were proposed as the alternative to HFC refrigerants for refrigeration system. In this report, the combinations of the low GWP refrigerants and lubricants were evaluated. The evaluation items are physical properties (miscibility, solubility, viscosity, and electric property)and thermal stability

An acceleration search method of higher Tc superconductors by a machine learning algorithm

We propose a method to efficiently search for superconductors with higher critical temperature Tc by machine learning based on a superconductor database. The Tc prediction and the search for new superconductors are still difficult problems. With the progress of computer power and calculation algorithms, the possibility of finding new materials with higher Tc at high throughput is emerging. Using the obtained Tc prediction model, the scope is expanded to the search space of multielement materials that have never been searched, and candidates for superconductors with higher Tc that can be synthesized are proposed

Factor Analysis of Damage to Small Earth Dams Due to the 1995 Hyogoken-Nambu Earthquake

Damage to small earth dams due to the Hyogoken-Namby Earthquake of January 17, 1995 is discussed. Investigations of 266 dams were conducted in the area where the JMA seismic intensity was 5 or higher, and which were located within about 50 kilometers from the earthquake source fault. Small earth dams suffered various forms of damage such as longitudinal cracking, transverse cracking, settlement and deformation of the dam body. The damage to small earth dams was classified into five grades from no damage to severe damage such as a complete failure. The damage grade was analyzed by several factors such as distance from the fault, topography and geology, intensity of quake motion, direction of dam axis against the fault, year of completion, and height of dam. The characteristics of factors affecting damage to small earth dams were evaluated