General Properties of Low-frequency Power Losses in Fe-based Nanocrystalline Soft Magnetic Alloys

The dependences of the power loss per cycle on frequency f and amplitude flux density Bm have been investigated for the three main original magnetic states in five sorts of Fe-based nanocrystalline soft magnetic alloys in the ranges of 10 Hz<=f<=1000 Hz and 0.4 T<= Bm <=1.0 T. The total loss P is decomposed into the sum of the hysteresis loss Physt, the classical eddy current loss Pel and the excess loss Pexc. Physt has been found to be proportional to Bm^2 and f. The behavior of Pexc/f vs f being equivalent to P/f vs f clearly exhibits nonlinearity in the range not more than about 120 Hz, whereas the behavior of P/f vs f roughly shows linearity in the range far above 100 Hz and not more than 1000 Hz. In the range up to 1000 Hz, Physt is dominant in the original high permeability state and the state of low residual flux density, whereas Pexc in the state of high residual flux density is dominant in the wider range above about 100 Hz. The framework of the statistical theory of power loss has been used for representing the behavior of Pexc/f vs f. It has been found that the number n of the simultaneously active 'Magnetic Objects' linearly varies as n = n0 + Hexc/H0 as a function of the dynamic field Hexc in the range below about 120 Hz, whereas n approximately follows a law of the form n = n0 + (Hexc/H0)^m with 1 < m < 2 in the range far above 100 Hz and not more than 1000 Hz. The values of the field HO in principle related to the microstructure and the domain structure have been calculated for the three states.

Intellectual Property Protection and High-Quality Development of Xinjiang Melons under the Big Food Concept

The development of diversified foods such as melons under the big food concept can reduce the pressure on staple food grain.Xinjiang has the advantages of building a new development pattern of dual circulation of diversified food industry and establishing a national diversified food safety and high-quality assurance center.The construction of an agricultural power needs the strategic support of an intellectual property power.This paper introduced and studied Xinjiang s melon industry and its agricultural intellectual property resources,analyzed the six main problems,including many idle land resources have not been developed into melon fields and the role of melons in diversified food supply systems not well played.Finally,it proposed to vigorously develop diversified food industries such as melons in Xinjiang and establish an eight-point strategy such as national diversified food safety and high-quality assurance center.

Influence of Structure Parameters on Performance of the Thermoelectric Module

A numerical model of thermoelectric module （TEM） is created by academic analysis,and the impacts of the resistance ratio and thermoelement size on the output power and thermoelectric efficiency of the TEM are analyzed by the MATLAB numerical calculation.The numerical model is validated by the ANSYS thermal,electrical,and structural coupling simulation.The effects of the variable physical property parameters and contact effect on the output power and thermoelectric efficiency are evaluated,and the concept of aspect ratio optimal domain is proposed,which provides a new design approach for the TEM.

Thermoelectric properties of Yb x Co_4 Sb_(12) system

Yb x Co 4 Sb 12 polycrystals were fabricated by vacuum melting combined with hot-press sintering.The effect of Yb-filling on thermoelectric property of unfilled skutterudite CoSb 3 was investigated,which indicated the enhancement of the power factor of the material.Transport properties of materials changed from semi-conductor to semi-metal during the measurement of electrical conductivity,which indicated the change of electronic band structure.The maximum value of electrical conductivity was about 190000 S/m at 300 K for all samples.On the basis of Yb-filling,power factor of Yb 0.2 Co 4 Sb 12 reached 5-6 mW/（m·K） during the measurement temperature.Thermal conductivity decreased with increase of Yb content,and the thermal conductivity of Yb 0.2 Co 4 Sb 12 reached 3.2 W/（m·K） at 600 K.The ZT value of Yb 0.2 Co 4 Sb 12 reached 1.16 at 700 K due to positive contribution from high power factor and low thermal conductivity.

Intellectual Property Policy and County Economic Growth:A Quasi-natural Experiment from the Intellectual Property Powering County Project

As fundamental economic units,county economies play a crucial role in China's national economic system.However,it remains unclear whether intellectual property rights policies at the county level can promote economic growth.We used a quasi-natural experiment from the Intellectual Property Powering County Project("the Project")to measure their impact on county economic growth from 2009 to 2020,applying a multi-period diference-in-differences method.County economic growth indicators were measured using Enhanced Vegetation Index-calibrated nighttime light data from the Defense Meteorological Satellite Program and Visible Infrared Imaging Radiometer Suite.The findings demonstrated that the Project promoted economic growth significantly by incentivizing innovation,attracting high-tech and new-tech enterprises,and fostering brand creation.The Project also exhibited significant heterogeneity across districts and counties,along with spillover effects on economic growth in surrounding counties within approximately 80 kilometers.