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The efficiency of the electrochemical performance of the separator in supercapacitors (SCs) is primarily determined by the ion transport performance, which in turn depends on the pore size uniformity and electrolyte absorption. Cellulose separators with high electrolyte absorption are expected to exhibit outstanding ion transport; however, they remain largely unexplored. Here, we report the fabrication of cellulose separators that feature a hierarchically cross-linked network, and tightly stacked structures can achieve extremely low separator resistivity and enhanced ion transport properties. Compared with common separators, this work enables the investigation of ionic transport in greater detail. High electrolyte absorptivity is realized due to its uniform pore environment, high pore density, hydrophilicity, ultrathin thickness, and reduced impedance, which guarantees the excellent ion transport performance of the separator. The high thermal stability of regenerated cellulose enables the separator to preserve its structural integrity at temperatures as high as 200 °C, thereby ensuring the safety of supercapacitors. This work opens up the application of an ultrathin regenerated cellulose separator with enhanced ion transport performance in large-scale industrialized production with implications that can promote the development of safe and high-performance separators. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is both a nutrient and a pollutant. For instance, excess P induces water eutrophication followed by death of fishes and other water life. Determination of organic P content in sediments is therefore important to study P cycling and environmental pollution. The most widely used method to determine organic P in sediments is NaOH-EDTA extraction followed by P-NMR detection. However, some organic P compounds are difficult to extract using NaOH-EDTA due to the low solubility, thus can not be detected by P NMR. Here, we used foam separation to determine organic P in sediment of North Canal of Tianjin City, China. Organic P was first enriched using foam separation coupled with NaOH extraction. The enriched organic P was then analyzed with P NMR. The results showed that, compared with the traditional extraction method, foam separation coupled with NaOH extraction enriched more P compound because P NMR detected an extra signal of teichoic acid at chemical shift 1.14. This teichoic acid signal was not detected in the extract prepared using only NaOH-EDTA. Our finding demonstrates that determination using foam separation followed by P NMR is feasible. [ABSTRACT FROM AUTHOR]

Objectives: Aim was to evaluate anti-Müllerian-hormone (AMH) in women with polycystic ovary syndrome (PCOS) comparing with normo-ovulatory women, and to assess for the first time AMH levels across reproductive lifespan in Chinese women. Methods: Within the prospective cross-sectional study in PCOS cases and in normal subjects, AMH and other hormone levels were measured in early follicular phase in five age groups. Additionally ovarian ultrasound parameters were assessed. Results: A total of 437 PCOS patients and 150 normo-ovulatory women matched by age were included. AMH levels were 2- to 3-fold higher in PCOS cases. In both groups AMH decreased with age in a non-linear pattern. In normo-ovulatory women AMH levels were relatively constant from 18 to 25 years and then declined with age. In contrast, AMH in PCOS cases declined with an increasing rate from 18 to 45 years, narrowing the difference in older women. Conclusions: AMH may be a useful parameter to assess the severity and prognosis of PCOS since certain differences exist to normo-ovulatory women. Further studies may improve the understanding of the relationship between AMH levels and age, providing more scientific basis for fertility counselling for both healthy women and PCOS cases. [ABSTRACT FROM AUTHOR]