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61.
Hierarchical nanostructures with highly exposed active surfaces for high‐performance pseudocapacitors have attracted considerable attention. Herein, a one‐step growth of (Ni xCo1?x)9Se8 solid solution series in various conductive substrates as advanced electrodes for flexible, foldable supercapacitors is developed. The formation of (NixCo1?x)9Se8 solid solution is confirmed by Vegard's law. Interestingly, the as‐grown (NixCo1?x)9Se8 solid solution series spontaneously crystallized into nanodendrite arrays with hierarchical morphology and fractal feature. The optimized (Ni0.1Co0.9)9Se8 nanodendrites deliver a specific capacitance of 3762 F g?1 at a current density of 5 A g?1 and remains 94.8% of the initial capacitance after 5000 cycles, owing to the advantage from fractal feature with numerous exposed () surface as well as fast ion diffusion. The as‐assembled flexible (Ni0.1Co0.9)9Se8@carbon fiber cloth (CFC)//PVA/KOH//reduced graphene oxide@CFC device exhibits an ultrahigh energy density of 17.0 Wh kg?1@ 3.1 kW kg?1, outperforming recently reported pseudocapacitors based on nickel‐cobalt sulfide and selenide counterparts. This study provides rational guidance toward the design of fractal feature with superior electrochemical performances due to the significantly increased electrochemical active sites. The resulting device can be easily folded, pulled, and twisted, enabling potential applications in high‐performance wearable and gadget devices.  相似文献   
62.
用含20-160nl/lSO2的空气熏气处理过的油菜在25℃下饲养桃蚜MyzusPersicae,研究SO2污染对这种蚜虫的影响。结果表明,蚜虫的反应与SO2剂量有关:低、中浓度的SO2处理显著促进了桃蚜的生长和繁殖;SO2浓度约为80nl/l时,它们的反应最敏感,若蚜的平均相对生长速率(MRGR)、成蚜的繁殖力和种群的内禀增长力(rm)分别比对照组增加31.5%、89.8%和42.7%;高浓度SO2污染的油菜严重抑制桃蚜的生长和繁殖。对被处理植物营养成分的分析表明,SO2污染引起的蛋氨酸相对含量变化可能是造成这种剂量—反应关系的主要原因。  相似文献   
63.

Objective

Objectives of this study were 1) to investigate the mineral intake by Chinese lactating women, 2) to explore the dietary source of minerals, and 3) the ratios between different dietary minerals.

Methods

A total of 468 lactating women in 5–240 days post-partum participated in this study. Food intakes by participants were measured using one time of 24-hour dietary recall, and minerals from food were calculated based on the Chinese Food Composition Table, second edition.

Results

In post-partum, women had inadequate food intake. 81.0% of women’s daily intake of dairy products was lower than 300g, and 97.1% of women’s daily intake of salt over 6g. For mineral intake, there were 81.8%, 59.0%, 47.6%, 45.7% and 66.8% of women’s calcium, magnesium, iron, zinc and selenium intake lower than the estimated average requirement, respectively, and 91.7% of women’s excessive intake of sodium. The calcium/phosphorus and sodium/potassium ratios were 0.41±0.26/1 and 3.13±2.89/1, respectively. Considering the dietary sources of minerals, 27.3%, 25.3% and 30.1% of iron, zinc and calcium were from animal-based food, respectively, and 60.3%, 66.1% and 58.0% of iron, zinc and calcium were from plant-based food, respectively. The phosphorus-protein ratio was 0.014±0.003/1. Lactation stage was associated with nutrient intake. Women within 30 days post-partum and the ones who live in Guangzhou had a significantly lower intake of certain minerals, while women with a high education experience had a high intake of calcium, potassium, iron and zinc. Productive age, whether obese or not, and delivery ways were not associated with mineral intakes (P all >0.05).

Conclusion

Chinese women in three studied cities had an inappropriate food intake and resulted in both insufficient and excessive intakes of certain minerals.  相似文献   
64.
A sequencing batch reactor (SBR) was used to test the nitrogen removal performance of anaerobic ammonium oxidation (ANAMMOX) in presence of organic matter. Mesophilic operation (30 ± 0.5 °C) was performed with influent pH 7.5. The results showed, independent of organic matter species, ANAMMOX reaction was promoted when COD was lower than 80 mg/L. However, specific ANAMMOX activity decreased with increasing organic matter content. Ammonium removal efficiency decreased to 80% when COD of sodium succinate, sodium potassium tartrate, peptone and lactose were 192.5, 210, 225 and 325 mg/L, respectively. The stoichiometry ratio resulting from different OM differed largely and R1 could be as an indicator for OM inhibition. When COD concentration was 240 mg/L, the loss of SAA resulting from lactose, peptone, sodium potassium tartrate and sodium succinate were 28, 36, 50 and 55%, respectively. Sodium succinate had the highest inhibitory effect on SAA. When ANAMMOX process was used to treat wastewater containing OM, the modified Logistic model could be employed to predict the NREmax.  相似文献   
65.
部分植物抗氧化活性的初步研究   总被引:26,自引:0,他引:26  
用DPPH法测定了20多种植物的抗氧化活性,其中火炬树、法国梧桐等7种植物的叶或其它部位的抗氧化活性较高,与银杏叶的接近或相当,值得进一步研究。  相似文献   
66.
67.
用PCR 方法从芝田硫化叶菌中扩增了编码一种新酶,即麦芽寡糖基海藻糖合酶( MTSase) 的基因,扩增的2-2kb DNA 插入到原核表达载体pBV220 中,构建成重组质粒pSBGT1 。pSBGT1 中MTSase 基因在大肠杆菌中得到表达。SDSPAGE 分析表达产物MTSase蛋白的分子量约为74kDa ,同核苷酸序列测定所推导的值相符。表达产物占细胞总蛋白约4-4 % 。pSBGT1 产生的重组酶作用于淀粉部分水解物,使DE 值降低,得到非还原糖或低还原糖。  相似文献   
68.
69.
Chen  Peiyu  Yang  Beining  Wu  Yanru  Wang  Jiawei 《Molecular and cellular biochemistry》2020,474(1-2):209-218
Molecular and Cellular Biochemistry - Local injection of tumor necrosis factor-alpha (TNF-α) at bone fracture sites during the early stage of the inflammatory response is reported to improve...  相似文献   
70.
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