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91.
Output voltage and self‐discharge rate are two important performance indices for supercapacitors, which have long been overlooked, though these play a very significant role in their practical application. Here, a zinc anode is used to construct a zinc ion hybrid capacitor. Expanded operating voltage of the hybrid capacitor is obtained with novel electrolytes. In addition, significantly improved anti‐self‐discharge ability is achieved. The phosphorene‐based zinc ion capacitor exploiting a “water in salt” electrolyte with a working potential can reach 2.2 V, delivering 214.3 F g?1 after 5000 cycles. The operating voltage is further extended to 2.5 V through the use of an organic solvent as the electrolyte; the solvent is prepared by adding 0.2 m ZnCl2 into the tetraethylammonium tetrafluoroborate in propylene carbonate (Et4NBF4/PC) solvent, and it exhibits 105.9 F g?1 even after 9500 cycles. More importantly, the phosphorene‐based capacitors possess excellent anti‐self‐discharge performance. The capacitors retain 76.16% of capacitance after resting for 300 h. The practical application of the zinc ion capacitor is demonstrated through a flexible paper‐based printed microcapacitor. It is believed that the developed zinc ion capacitor can effectively resolve the severe self‐discharge problem of supercapacitors. Moreover, high‐voltage zinc ion capacitors provide more opportunities for the application of supercapacitors.  相似文献   
92.
Glutathione (GSH) serves as an important anti-oxidant in the brain by scavenging harmful reactive oxygen species that are generated during different molecular processes. The GSH level in the brain provides indirect information on oxidative stress of the brain. We report in vivo detection of GSH non-invasively from various brain regions (frontal cortex, parietal cortex, hippocampus and cerebellum) in bilateral hemispheres of healthy male and female subjects and from bi-lateral frontal cortices in patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD). All AD patients who participated in this study were on medication with cholinesterase inhibitors. Healthy young male (age 26.4±3.0) and healthy young female (age 23.6±2.1) subjects have higher amount of GSH in the parietal cortical region and a specific GSH distribution pattern (parietal cortex>frontal cortex>hippocampus ~ cerebellum) has been found. Overall mean GSH content is higher in healthy young female compared to healthy young male subjects and GSH is distributed differently in two hemispheres among male and female subjects. In both young female and male subjects, statistically significant (p=0.02 for young female and p=0.001 for young male) difference in mean GSH content is found when compared between left frontal cortex (LFC) and right frontal cortex (RFC). In healthy young female subjects, we report statistically significant positive correlation of GSH content between RFC and LFC (r=0.641, p=0.004) as well as right parietal cortex (RPC) and left parietal cortex (LPC) (r=0.797, p=0.000) regions. In healthy young male subjects, statistically significant positive correlation of GSH content was observed between LFC and LPC (r=0.481, p=0.032) regions. This statistical analysis implicates that in case of a high GSH content in LPC of a young male, his LFC region would also contain high GSH and vice versa. The difference in mean of GSH content between healthy young female control and female AD patients in RFC region (p=0.003) and difference in mean of GSH content between healthy young male control and male AD patients (p=0.05) in LFC region is found to be statistically significant. It is the first scientific report correlating alteration (in selective brain regions) of GSH level with clinical status of male and female subjects using non-invasive imaging technique.  相似文献   
93.
羧酸酯酶是昆虫体内重要的代谢解毒酶系,其主要功能是水解和结合内源性和外源性含有酯键的有毒物质,减缓其到达靶标部位的时间。东亚飞蝗Locusta migratoria manilensis(Meyen)是我国重要的农业害虫,对其羧酸酯酶基因克隆和表达有助于深入探索杀虫剂代谢毒理机制。本研究首先对羧酸酯酶基因(CarE4)进行了克隆,并将其插入到pCold TF DNA Vector中,在大肠杆菌中进行了原核表达,最后用疏水层析和离子交换层析方法对目的蛋白进行了纯化。本文成功建立了羧酸酯酶蛋白原核表达和纯化技术体系,为进一步研究东亚飞蝗羧酸酯酶的生理功能、结构特点和作用原理提供了基础资料。  相似文献   
94.
The epidemic of rabies has rapidly increased and expanded in Yunnan province in recent years.In order to further analyze and understand the etiological reasons for the rapid expansion of rabies in Yunn...  相似文献   
95.
96.
Plant genomes encode diverse small RNA classes that function in distinct gene‐silencing pathways. To elucidate the intricate regulation of microRNAs (miRNAs) and endogenous small‐interfering RNAs (siRNAs) in response to chilling injury in tomato fruit, the deep sequencing and bioinformatic methods were combined to decipher the small RNAs landscape in the control and chilling‐injured groups. Except for the known miRNAs and ta‐siRNAs, 85 novel miRNAs and 5 ta‐siRNAs members belonging to 3 TAS families (TAS5, TAS9 and TAS10) were identified, 34 putative phased small RNAs and 740 cis/trans‐natural antisense small‐interfering RNAs (nat‐siRNAs) were also found in our results which enriched the tomato small RNAs repository. A large number of genes targeted by those miRNAs and siRNAs were predicted to be involved in the chilling injury responsive process and five of them were verified via degradome sequencing. Based on the above results, a regulatory model that comprehensively reveals the relationships between the small RNAs and their targets was set up. This work provides a foundation for further study of the regulation of miRNAs and siRNAs in the plant in response to chilling injury.  相似文献   
97.
探讨用密度梯度离心法快速、有效地分离大鼠卵泡膜细胞.选取23~25 d雌性大鼠卵巢,用Percoll密度梯度离心法将卵泡膜细胞分离纯化,3β-羟基类固醇脱氢酶(3β-hydroxysteroid dehydrogenase,3β-HSD)组织化学染色用于卵泡膜细胞纯度检测.分别用0.1 U/mL和1.0 U/mL卵泡刺激素(Follicle-stimulating hormone,FSH)及黄体生成素(luteinizing hormone,LH)处理细胞,无血清培养48 h后,酶联免疫法检测培养液中雄烯二酮和雌二醇的水平.分离所得细胞中,3β-HSD染色阳性细胞与总细胞数之比大于90%; LH组的雄烯二酮水平显著高于对照组和FSH组(P<0.05),LH组中1.0 U/mL组的雄烯二酮水平又高于0.1 U/mL组.各组均未检测到雌二醇及孕酮.3β-HSD组织化学染色可快速有效地检验所分离的卵泡膜细胞的纯度,分离所得的卵泡膜细胞可对LH产生反应,且其中几乎没有混杂颗粒细胞.  相似文献   
98.
基于江西省地面气象资料和农业气象试验站数据,分析了江西省双季稻生育期的变化趋势,并利用生长度日(GDD)、低温度日(CDD)和高温度日(HDD)对1981-2007年江西省水稻各生育期热量资源的变化趋势进行分析.结果表明:气候变暖背景下,江西省水稻生长季平均气温、平均最低气温和平均最高气温均呈升高趋势,引起双季稻生长季缩短,其中,营养生长期日数减少最明显,而生殖生长期延长;生长度日和高温度日均增加,低温度日减少.研究期间,江西省双季稻有效热量资源增加,低温风险减少,但高温风险增多;江西省水稻有效热量资源的空间变化特征表现为东北部的增幅大于西南部,南部的低温风险大于北部,中部的高温风险最大.  相似文献   
99.
目的:研究大黄素对IFN-和LPS刺激的人结肠癌细胞株HT-29细胞的ERK、JNK和p38 MARK和IL-8表达的影响。方法:人结肠癌细胞株HT-29细胞与40 ng/mL的IFN-共培养12 h,再加入100 ng/mL LPS刺激15 min,用大黄素预处理进行干预。ELISA检测HT-29细胞内的ERK、JNK和p38 MARK含量和细胞上清IL-8含量。结果:IFN-γ和LPS刺激后HT-29细胞的ERK、JNK和p38 MARK磷酸化水平和IL-8分泌明显升高。大黄素对p38和JNK磷酸化有明显的抑制作用,而对ERK磷酸化则没有明显抑制作用;大黄素能显著降低IFN-γ+LPS所引起的HT-29细胞IL-8的大量产生,并且呈明显的剂量依赖关系。结论:大黄素能有效抑制IFN-γ+LPS所引起的HT-29细胞p38和JNK的磷酸化,并显著降低IL-8分泌。  相似文献   
100.
三峡大坝下游残存疏花水柏枝种群结构和动态   总被引:1,自引:0,他引:1  
在三峡大坝下游的湖北宜都关洲设立1个40 m×40 m的固定样地,利用高度分级,比较2008与2009年两年间的疏花水柏枝(Myricaria laxiflora)种群数量动态,并运用点格局的Ripley's K函数分析了其空间格局变化及种群更新特征。结果表明,疏花水柏枝幼苗数量较少,种群更新存在一些障碍。空间分布格局与空间尺度及植株的大小密切相关。种群总体呈集群分布,各大小级多在9 m时出现最大的聚集强度,随着大小级的增加,聚集强度有减弱的趋势。幼苗与中株有较强的正关联。由于种群现有生境变化较大,应考虑迁地保护,并对原生种群加强长期动态监测;同时,开展疏花水柏枝适应机理研究,实施科学保护。  相似文献   
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