Sodium oxalate (Na 2 C 2 O 4 ) is an excellent phosphorus-free agent, but in sodium oxalate-containing detergents with sodium dodecylbenzene sulfonate (SDBS) and sodium carboxymethyl cellulose (CMC), significant ash deposition occurs on cotton fabrics. SDBS is the main anionic surfactant in modern detergents and cotton fiber is the most commonly used textile fiber. In this study, sodium lignosulfonate (LS) was investigated for its ability to prevent redeposition in SDBS-Na 2 C 2 O 4 -CMC-LS formulations. The effects of LS on ash content, whiteness, optimum washing temperature, calcium oxalate morphology, zeta potential and surface tension were carefully analyzed. The results showed that the addition of LS significantly improved the prevention of ash deposits on cotton fibers. The ash content was less than 0.46% and a small amount of particles were scattered on the cotton fibers. LS showed good dispersibility but had little effect on the washing power and zeta-potential.
Zihan Zhou,Yunwen Wu,Huiqin Ling,Jie Guo,Su Wang,Ming Li
3D NAND flash memory with vertically stacked cells has been developed to break through the limits of technology nodes. However, during the selective etching process, it is difficult to ensure the byproducts diffuse away from the trenches in the multistacked layers. Once saturated, the byproduct causes abnormal redeposition on the SiO 2 layers. This problem has restricted the development of high-density 3D NAND memory. To solve this problem, the composition and formation mechanism of the redeposited layer must be clarified. In this study, a ternary-wafer system comprising a Si 3 N 4 /SiO 2 /Si 3 N 4 stack was fabricated to study the redeposition mechanism, and the morphology, elastic properties , and chemical composition of the redeposited layer were clarified. The redeposited layer consists of spherical particles with elastic surfaces (average Young’s modulus of 24.17 GPa). The particles were confirmed to comprise colloidal silica gel covered by silanols . By considering the chemistry of silica , the redeposition mechanism was proposed as follows: colloidal silica gel is formed by the aggregation of silicic acids from Si 3 N 4 etching, which adsorb onto the SiO 2 layer through oxide bridges and hydrogen bonding . Our work will contribute to the development of high-density 3D NAND memory.
Rapid development of electronic technology shortens the development time for new products and accelerates the obsolescence of consumer electronics, resulting in the explosive growth of electronic waste that is difficult to recycle and hazardous to the environment and human health. Transient electronics that can dissolve in water may potentially be adopted to tackle the issues of electronic waste; however, promising approaches to yield large-scale and high-performance transient consumer electronics have not yet been developed. Here, the joint effect of galvanic corrosion and redeposition has been utilized to develop bimetallic transient nanocomposites, which can be printed and water-sintered to yield high-performance transient PCB circuits with excellent electrical conductivity and mechanical robustness. The entire sintering process requires no external energy and strict environmental conditions. The achieved PCB circuits offer a conductivity of 307,664.4 S/m that is among the highest in comparison with other printed transient circuits. The supreme performance of the transient circuits eventually leads to the first dissolvable smartwatch that offers the same functions and similar performance as conventional smartwatches and dissolves in water within 40 h. The joint effect of galvanic corrosion and redeposition between two metals with distinct activities leads to novel nanocomposites and processing techniques of transient electronics. The resulting high-performance transient devices may reshape the appearance of consumer electronics and reform the electronics recycling industry by reducing recycling costs and minimizing environmental pollution and health hazard.
危险品化学品经营许可证（带存储）