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1.
Nowadays, millimeter scale power sources are key devices for providing autonomy to smart, connected, and miniaturized sensors. However, until now, planar solid state microbatteries do not yet exhibit a sufficient surface energy density. In that context, architectured 3D microbatteries appear therefore to be a good solution to improve the material mass loading while keeping small the footprint area. Beside the design itself of the 3D microbaterry, one important technological barrier to address is the conformal deposition of thin films (lithiated or not) on 3D structures. For that purpose, atomic layer deposition (ALD) technology is a powerful technique that enables conformal coatings of thin film on complex substrate. An original, robust, and highly efficient 3D scaffold is proposed to significantly improve the geometrical surface of miniaturized 3D microbattery. Four functional layers composing the 3D lithium ion microbattery stacking has been successfully deposited on simple and double microtubes 3D templates. In depth synchrotron X‐ray nanotomography and high angle annular dark field transmission electron microscope analyses are used to study the interface between each layer. For the first time, using ALD, anatase TiO2 negative electrode is coated on 3D tubes with Li3PO4 lithium phosphate as electrolyte, opening the way to all solid‐state 3D microbatteries. The surface capacity is significantly increased by the proposed topology (high area enlargement factor – “thick” 3D layer), from 3.5 μA h cm?2 for a planar layer up to 0.37 mA h cm?2 for a 3D thin film (105 times higher).  相似文献   
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Background and objectiveSince ancient times, honey has been used due to its nutritional and therapeutic value. The role of honey has been acknowledged in the scientific literature however, its use has been controversially discussed and has not been well accepted in modern medicine especially for diabetic patients. This study aimed to investigate the role of honey in diabetic patients.MethodsIn this study, we identified 107 research articles from data based search engines including “PubMed”, “ISI-Web of Science”, “Embase” and “Google Scholar”. The research papers were selected by using the primary key-terms including “Honey”, “Honey bee” and “Diabetes Mellitus”. The research documents in which “Honey” and “Diabetes Mellitus” were debated are included. After screening, we reviewed 66 papers and finally we selected 35 studies which met the inclusion criteria and the remaining documents were excluded.ResultsThis study investigated the preclinical, clinical, human and animal model studies on honey and diabetes mellitus and found that honey decreases the fasting serum glucose, increases the sting C-peptide and 2-h postprandial C-peptide. Although, there is a dearth of data and literature also contrary discussed the use of honey in diabetic patients.ConclusionHoney decreases the fasting serum glucose, increases fasting C-peptide and 2-h postprandial C-peptide. Honey had low glycemic index and peak incremental index in diabetic patients. The use of honey in diabetic patients still has obstacles and challenges and needs more large sample sized, multi-center clinical controlled studies to reach better conclusions.  相似文献   
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红壤退化地森林恢复后土壤有机碳对土壤水库库容的影响   总被引:1,自引:0,他引:1  
亚热带红壤侵蚀退化地实施生态恢复后生物生产力恢复迅速,但土壤尤其是土壤水库的功能并未获得同步恢复,导致土壤水库对于降水和地表径流的调节能力低下,区域性洪涝灾害和季节性干旱依然突出。采用野外调查和室内分析相结合的方式,研究了南方红壤侵蚀退化地典型植被恢复类型(马尾松与阔叶树复层林、木荷与马尾松混交林、阔叶混交林)0—60cm土层土壤水库各种库容差异,以及土壤总有机碳和活性有机碳密度分布特征,采用典型相关分析方法对土壤水库库容与土壤有机碳密度两组指标进行相关分析。结果表明:随着土层深度的增加,各森林恢复类型死库容呈上升趋势,兴利库容和最大有效库容呈下降趋势,防洪库容变化趋势不明显,木荷与马尾松混交林兴利库容略高。不同森林恢复类型同一土层土壤总有机碳密度均表现为马尾松与阔叶树复层林木荷与马尾松混交林阔叶混交林,而活性有机碳密度则以阔叶混交林最大。典型相关分析表明,土壤有机碳水平对土壤水库库容的增加具有显著的因果影响关系(P=0.01),其中对有机碳水平起到主导性贡献作用的是水溶性有机碳。因此,对于退化红壤地森林恢复初期,可通过适当密植和立体种植,提高林地生物量和土壤碳密度,并在马尾松等先锋树种针叶林分中补植阔叶乔灌木,以增加土壤活性有机碳含量,增大土壤水库容量,从而有利于土壤水库结构和功能以及退化生态系统的快速恢复。  相似文献   
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本文利用甲醇溶剂对酿酒葡萄皮渣进行浸提,得到白藜芦醇粗提物.粗提物通过硅胶柱层析进行纯化.然后,研究了白藜芦醇的氧自由基、超氧阴离子自由基、羟自由基、DPPH自由基的清除能力.结果显示:白藜芦醇具有很强的自由基清除能力和抗氧化能力,并且随着浓度的增加,抗氧化能力增强.  相似文献   
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不同经营方式下毛竹光合特性分异研究   总被引:2,自引:0,他引:2  
林木经营方式与林内光照、温度、水分及养分格局关系密切,影响到植株的光合水平。为探明毛竹对不同经营方式的光合响应特性,以安徽省黄山区3种经营方式下的5类毛竹林为对象开展研究,即:粗放经营(Ⅰ)、一般经营(Ⅱ)和集约经营(Ⅲ-挖冬笋量10%—15%,、Ⅳ-挖冬笋量15%—20%、Ⅴ-挖冬笋量约10%,每年9月施氮肥)。结果表明:1)不同经营方式下毛竹的叶面积指数(LAI)和SPAD值间存在显著差异,随经营程度的增加,LAI和SPAD值波动增大。2)光响应曲线变化趋势基本一致,非直角双曲线拟合良好,方程决定系数均大于0.96,随光合有效辐射(PAR)增强,净光合速率(P_n)、气孔导度(C_d)、蒸腾速率(T_r)、胞间二氧化碳浓度(C_i)随之降低,非集约经营(Ⅰ、Ⅱ)的总体变化水平高于集约经营下的Ⅳ和Ⅲ,但集约经营下的Ⅴ则与Ⅰ、Ⅱ趋势更接近,说明适当补充养分(Ⅴ)的集约经营能有效提高毛竹对光能的利用能力。3)光饱和点(LSP)、光补偿点(LCP)和暗呼吸速率(R_d)3个参数均最大或最小的两种经营方式下,毛竹林具较高的适应性,表现为最大净光合能力(P_(nmax))显著高于其它经营方式毛竹林,由此推断,粗放经营(Ⅰ)或有效补充林地养分的集约经营(Ⅴ)的毛竹具有较高的光合能力。  相似文献   
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长期保护性耕种方式对农田表层土壤性质的影响   总被引:17,自引:1,他引:16  
张国盛  K Y Chan  G D Li  D P Heenan 《生态学报》2008,28(6):2722-2722~2728
研究了不同耕种方式对澳大利亚同一地区3种土壤表层(0~5cm)理化性质的作用,以揭示保护性耕作对土壤质量恢复的影响.结果表明:免耕穴播/保留残茬(DD/SR)、多年生人工草地(PP)和自然草地(NP)表层土壤的>2mm水稳性团聚体含量、全氮、有机碳含量、田间持水量均显著高于其相应对照传统耕作/秸秆焚烧(CC/SB)、人工草地/作物轮作(PPC)和耕作(CT)的;土壤全氮含量、田间持水量分别与有机碳含量之间有极显著的正相关关系(r=0.994**,r=0.996**,n=6),而受土壤质地等因素的影响较小;在同一类型的土壤上,土壤有机碳含量与水稳定性团聚体含量之间存在显著的相关性;在不同试验区,耕作措施对表层土壤容重和孔隙分布的影响存在较大差异;秸秆焚烧和施用石膏对表层土壤的pH及交换性阳离子含量有较大的影响.研究表明长期保护性耕作、草田轮作或多年生草地有利于提高表层土壤有机碳含量和结构稳定性,从而改善土壤的供肥供水能力.  相似文献   
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The synthesis of novel indolopyrazoline derivatives (P1-P4 and Q1-Q4) has been characterized and evaluated as potential anti-Alzheimer agents through in vitro Acetylcholinesterase (AChE) inhibition and radical scavenging activity (antioxidant) studies. Specifically, Q3 shows AChE inhibition (IC50: 0.68 ± 0.13 μM) with strong DPPH and ABTS radical scavenging activity (IC50: 13.77 ± 0.25 μM and IC50: 12.59 ± 0.21 μM), respectively. While P3 exhibited as the second most potent compound with AChE inhibition (IC50: 0.74 ± 0.09 μM) and with DPPH and ABTS radical scavenging activity (IC50: 13.52 ± 0.62 μM and IC50: 13.13 ± 0.85 μM), respectively. Finally, molecular docking studies provided prospective evidence to identify key interactions between the active inhibitors and the AChE that furthermore led us to the identification of plausible binding mode of novel indolopyrazoline derivatives. Additionally, in-silico ADME prediction using QikProp shows that these derivatives fulfilled all the properties of CNS acting drugs. This study confirms the first time reporting of indolopyrazoline derivatives as potential anti-Alzheimer agents.  相似文献   
10.
In order to search for novel multifunctional anti-Alzheimer agents, a series of ferulic acid–carbazole hybrid compounds were designed and synthesized. Ellman’s assay revealed that the hybrid compounds showed moderate to potent inhibitory activity against the cholinesterases. Particularly, the AChE inhibition potency of compound 5k (IC50 1.9 μM) was even 5-fold higher than that of galantamine. In addition, the target compounds showed pronounced antioxidant ability and neuroprotective property, especially against the ROS-induced toxicity. Notably, the neuroprotective effect of 5k was obviously superior to that of the mixture of ferulic acid and carbazole, indicating the therapeutic effect of the hybrid compound is better than the combination administration of the corresponding mixture.  相似文献   
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