[Advances in synthesis of succinic acid using yeast cell factories].

Succinic acid is an important C4 platform compound that serves as a raw material for the production of 1,4-butanediol, tetrahydrofuran, and biodegradable plastics such as polybutylene succinate (PBS). Compared to the traditional petrochemical-based route that uses maleic anhydride as a raw material, the microbial fermentation method for producing succinic acid offers more sustainable economic value and environmental friendliness. Yeasts with good acid tolerance can achieve low-pH fermentation of succinic acid, significantly reducing the cost of product extraction. Therefore, constructing high-yield succinic acid yeast strains through metabolic engineering has garnered increasing attention. This paper systematically introduced the application value and market size of succinic acid, summarized the pathways and key enzymes involved in succinic acid synthesis in microorganisms, and elaborated on the latest research progress in the synthesis of succinic acid using yeast cell factories. It also presented the current status of succinic acid synthesis using non-food raw materials such as glycerol, acetic acid, lignocellulosic hydrolysate, and others as substrates by engineered yeast strains. Finally, the paper provided a prospect for low-pH succinic acid biomanufacturing based on yeast cell factories.

Chemically Induced Activity Recovery of Isolated Lithium in Anode-free Lithium Metal Batteries.

The anode-free lithium metal battery is considered to be an excellent candidate for the new generation energy storage system because of its higher energy density and safety than the traditional lithium metal battery. However, the continuous generation of SEI or isolated Li hinders its practical application. In general, the isolated Li is considered electrochemically inactive because it loses electrical connection with the current collector. Here we show an abnormal phenomenon that the lost capacity appears to be recovered after cycles when the isolated Li reconnects with a deposited Li metal layer. The isolated Li reconnection is ascribed to the chemical induction of the block copolymer coating. The migration of Li+ is affected by the electron delocalization and the electron cloud density of the polymer, which determine the conversion direction of Li+. Based on the mechanism, we propose a strategy to slow down the capacity decay of the anode-free lithium metal battery.

Construction of a N,P doped 3D dendrite-free lithium metal anode by using silicon-containing lithium metal.

Lithium is thought to be an excellent anode material for next-generation Li metal batteries (LMBs). However, some problems with lithium anodes often lead to serious safety concerns and catastrophic failures due to the huge volume change, Li dendritic growth, and related side reactions. Therefore, in order to manufacture stable rechargeable batteries, the abovementioned serious problems must be effectively solved. In this paper, a three-dimensional N,P-doped silicon-containing lithium anode is designed and prepared by in situ metallurgy using low-cost Si3N4. The 3D stable composite anode (DLi/LiSix CA) was prepared by adding a small amount of Si3N4 to molten lithium to form N-doped silicon-containing lithium metal which was supported on a polyaniline modified carbon cloth (PMCC). The results show that the DLi/LiSix CA not only has high Li affinity but can also effectively inhibit lithium nucleation and lithium dendritic growth, so as to maintain good structural stability in the process of Li plating/stripping. The new lithium metal anode based on doping and 3D carbon cloth shows good cycling stability and low polarizability in both symmetrical and full cells.

Utilization of artificial recharged effluent as makeup water for industrial cooling system: corrosion and scaling.

The secondary effluent from wastewater treatment plants was reused for industrial cooling water after pre-treatment with a laboratory-scale soil aquifer treatment (SAT) system. Up to a 95.3% removal efficiency for suspended solids (SS), 51.4% for chemical oxygen demand (COD), 32.1% for Cl(-) and 30.0% SO4(2-) were observed for the recharged secondary effluent after the SAT operation, which is essential for controlling scaling and corrosion during the cooling process. As compared to the secondary effluent, the reuse of the 1.5 m depth SAT effluent decreased the corrosion by 75.0%, in addition to a 55.1% decline of the scales/biofouling formation (with a compacted structure). The experimental results can satisfy the Chinese criterion of Design Criterion of the Industrial Circulating Cooling Water Treatment (GB 50050-95), and was more efficient than tertiary effluent which coagulated with ferric chloride. In addition, chemical structure of the scales/biofouling obtained from the cooling system was analyzed.

[Studies on cold resistance of hazel determined and analyzed by atomic absorption spectrometry].

Using annual branch of hazel as the experimental materials, the K(+)-leakage and relative electric conductivity of three hazel species (six hazel clones) which had been treated with different low temperature were determined by electro-conductivity gauge and atomic absorption spectrometry. Regression models were established for low temperature to the K(+)-leakage or the relative electric conductivity of six hazel clones. The results showed that there was the same result of cold resistance for all clones using the two methods of comprehensive evaluation, and the indicator of K(+)-leakage rate determined by atomic absorption spectrometry can be used as a means of early identification of cold resistance of hazel clones. There were obvious differences among the clones in the ability of cold resistance. The order of the ability of cold resistance for the six hazel clones was C7R7 > Z-9-40 > C6R1 > CS2R1 > Z-9-22 > Z-9-30, and the order of the ability of cold resistance for the three hazel species was C. heterophylla > C. heterophyllax X (C. heterophylla X C. avellana) > C. heterophylla X C. avellana. The median lethal temperature of tissue for all clones is -26(-)-40 degrees "C.