A systematic construction of water-electricity cogeneration and thermal membrane coupling desalination technology using the waste heat in steel industry.

The widespread use of fossil energy emits a large amount of carbon dioxide, leading to the greenhouse effect and global warming. The essence of reducing carbon emissions is to achieve higher-quality sustainable development. The recycling of waste heat in the iron and steel industry is of great significance to reducing carbon emissions. Aiming at the problem of insufficient utilization of gas in iron and steel industry and the development of seawater desalination industry, a water-electricity cogeneration and thermal membrane coupling technology is established. Low-temperature multi-effect distillation seawater desalination device is directly connected with steam turbine generator, which uses gas to generate electricity. After generating electricity, negative pressure exhaust at the end of steam turbine is used for seawater desalination. The thermal efficiency of the system is increased to over 80%, the waste heat is effectively utilized, and the carbon emission in the thermal desalination process is reduced. At the same time, the high-efficiency removal and resource utilization of salt in concentrated seawater are realized. The recovery ratio of freshwater is over 55%, the salt content of freshwater is below 500 mg/L, and the salt content of seawater concentrated by membrane method can reach 79,450 mg/L. A new comprehensive utilization and recycling system of seawater has been constructed to realize efficient recycling of energy resources and promote the development process of carbon emission reduction.

Ni3 S2 -Ni Hybrid Nanospheres with Intra-Core Void Structure Encapsulated in N-Doped Carbon Shells for Efficient and Stable K-ion Storage.

Iron group metals chalcogenides, especially NiS, are promising candidates for K-ion battery anodes due to their high theoretical specific capacity and abundant reserves. However, the practical application of NiS-based anodes is hindered by slow electrochemical kinetics and unstable structure. Herein, a novel structure of Ni3 S2 -Ni hybrid nanosphere with intra-core voids encapsulated by N-doped carbon shells (Ni3 S2 -Ni@NC-AE) is constructed, based on the first electrodeposited NiS nanosphere particles, dopamine coating outer layer, oxygen-free annealing treatment to form Ni3 S2 -Ni core and N-doped carbon shell, and selective etching of the Ni phase to form intra-core void. The electron/K+ transport and K+ storage reaction kinetics are enhanced due to shortened diffusion pathways, increased active sites, generation of built-in electric field, high K+ adsorption energies, and large electronic density of states at Fermi energy level, resulting from the multi-structures synergistic effect of Ni3 S2 -Ni@NC-AE. Simultaneously, the volume expansion is alleviated due to the sufficient buffer space and strong chemical bonding provided by intra-core void and yolk-shell structure. Consequently, the Ni3 S2 -Ni@NC-AE exhibits excellent specific capacity (438 mAh g-1 at 0.1 A g-1 up to 150 cycles), outstanding rate performances, and ultra-stable long-cycle performance (176.4 mAh g-1 at 1 A g-1 up to 5000 cycles) for K-ion storage.

Measurement and calculation of surface tension of molten Sn-Bi alloy.

The surface tension of molten Sn-Bi (mole fraction X(Bi) = 0.455) alloy has been determined by the sessile drop method at oxygen partial pressure (P(O2)) of 1.0x10(-6) MPa and different temperatures. The experimental results have been analyzed and discussed, and the positive temperature coefficient of surface tension of molten Sn-Bi alloy has been elucidated. The surface tension of this molten alloy has also been obtained by calculation using STCBE based on Butler's equation and thermodynamic data. The experimental results agree well with the calculation values.

Effect of boron on the surface tension of molten silicon and its temperature coefficient.

The influence of boron concentration (C(B)/mass%) on the surface tension of molten silicon has been investigated with the sessile drop method under oxygen partial pressure P(O(2))=1.62x10(-25)-2.63x10(-22) MPa, and the results can be summarized as follows. The surface tension increases with C(B) in the range below 2.09 mass%, and the maximum increase rate of the surface tension is about 30 mN m(-1)(mass% C(B))(-1). The temperature coefficient of the surface tension, ( partial differential sigma/ partial differential T)C(B), was found to increase with the boron concentration in molten silicon. At the interface between molten silicon and the BN substrate, a discontinuous Si(3)N(4) layer was reckoned to form and the layer might prevent BN from dissolving into the molten silicon. Since dissolved boron from the BN substrate into the molten silicon is below 0.054 mass% and the associated increase in surface tension is below 1.5 mN m(-1), the contamination from the BN substrate on the surface tension can be ignored. The relation between the surface tension and C(B) indicates negative adsorption of boron and can be well described by combining the Gibbs adsorption isotherm with the Langmuir isotherm.

Shape change of prism solids in different liquid systems during local corrosion.

As reported in many previous publications, the cross section shape of prism solids will maintain the original square or become round after a certain duration of dipping and corrosion in certain melts. This paper gives theoretical explanations for these phenomena. Based on the deduction of the Laplace equation, it is found that for the solid-liquid system with contact angle (theta) smaller than 90 degrees, the maximum height of liquid surface on the lateral faces (H(f)) is greater than that at the prism edges (H(e)) before corrosion. If the corrosion and dissolution of the solid sample reduce the liquid surface tension, the case of H(f)>H(e) will be maintained or intensified due to the larger extent of dissolution at the edges, and the down-and-up motion of the liquid surface on the prism will mainly occur on the lateral faces, resulting in the maintenance of the original square shape of the sample's cross section. However, if the dissolution of the solid sample increases the liquid surface tension, the case H(f)90 degrees, the liquid surface height exhibits the opposite direction, and the evolution trends of the cross section shape are similar.