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The catalyst layer of the cathode is arguably the most critical component of low‐temperature fuel cells and carbon dioxide (CO2) electrolysis cells because their performance is typically limited by slow oxygen (O2) and CO2 reduction kinetics. While significant efforts have focused on developing cathode catalysts with improved activity and stability, fewer efforts have focused on engineering the catalyst layer structure to maximize catalyst utilization and overall electrode and system performance. Here, we study the performance of cathodes for O2 reduction and CO2 reduction as a function of three common catalyst layer preparation methods: hand‐painting, air‐brushing, and screen‐printing. We employed ex‐situ X‐ray micro‐computed tomography (MicroCT) to visualize the catalyst layer structure and established data processing procedures to quantify catalyst uniformity. By coupling structural analysis with in‐situ electrochemical characterization, we directly correlate variation in catalyst layer morphology to electrode performance. MicroCT and SEM analyses indicate that, as expected, more uniform catalyst distribution and less particle agglomeration, lead to better performance. Most importantly, the analyses reported here allow for the observed differences over a large geometric volume as a function of preparation methods to be quantified and explained for the first time. Depositing catalyst layers via a fully‐automated air‐brushing method led to a 56% improvement in fuel cell performance and a significant reduction in electrode‐to‐electrode variability. Furthermore, air‐brushing catalyst layers for CO2 reduction led to a 3‐fold increase in partial CO current density and enhanced product selectivity (94% CO) at similar cathode potential but a 10‐fold decrease in catalyst loading as compared to previous reports. 相似文献
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茶毛虫核型多角体病毒(EpNPV)多角体蛋白基因的定位及克隆 总被引:5,自引:0,他引:5
茶毛虫核型多角体病毒(Euproctis pseudoconspersa Nuclear Polyhedrosis Virus简称EpMPV),属于杆状病毒科核型多角体病毒属,能使茶毛虫染病死亡.EpNPV据报道最初由日本学者于1957年发现[1],随后在其它国家和地区也有相关报道[2];我国在贵州、湖北、广西和云南等地也有发现,并在EpNPV病毒杀虫剂的大田应用方面做了大量的工作,取得了一定的社会、经济和生态效益[3]. 相似文献
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Brian S. Baltunis Harry X. Wu Heidi S. Dungey T. J. “Tim” Mullin Jeremy T. Brawner 《Tree Genetics & Genomes》2009,5(1):269-278
Different methods for predicting clonal values were explored for diameter growth (diameter at breast height (DBH)) in a radiata
pine clonal forestry program: (1) clones were analyzed with a full model in which the total genetic variation was partitioned
into additive, dominance, and epistasis (Clone Only—Full Model); (2) clones were analyzed together with seedling base population
data (Clone Plus Seedling (CPS)), and (3) clones were analyzed with a reduced model in which the only genetic term was the
total genetic variance (Clone Only—Reduced Model). DBH was assessed at age 5 for clones and between ages 4 to 13 at the seedling
trials. Significant additive, dominance, and epistatic genetic effects were estimated for DBH using the CPS model. Nonadditive
genetic effects for DBH were 87% as large as additive genetic effects. Narrow-sense () and broad-sense () heritability estimates for DBH using the CPS model were 0.14 ± 0.01 and 0.26 ± 0.01, respectively. Accuracy of predicted
clonal values increased 4% by combining the clone and seedling data over using clonal data alone, resulting in greater confidence
in the predicted genetic performance of clones. Our results indicate that exploiting nonadditive genetic effects in clonal
varieties will generate greater gains than that typically obtainable from conventional family-based forestry of radiata pine.
The predicted genetic gain for DBH from deployment of the top 5% of clones was 24.0%—an improvement of more than 100% over
family forestry at the same selection intensity. We conclude that it is best practice to predict clonal values by incorporating
seedling base population data in the clonal analysis. 相似文献
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Brenda K. Wiederhold Albert “Skip” Rizzo 《Applied psychophysiology and biofeedback》1999,24(4):283-284
Authors Index
Author Index to Volume 24 相似文献8.
柯萨奇病毒B3基因组及其变异与心肌损伤的关系 总被引:1,自引:0,他引:1
肠道病毒感染是人类急性和慢性心肌炎的常见病因之一,而且也与人类扩张 型心肌病(DCM)的发生发展有密切关系 [1]}.病毒分离,血清学研究,免疫组化技术 、原位核酸杂交技术以及聚合酶链反应技术(PCR)均提示肠道病毒与心肌炎关系密切.最近 ,LI等 [2]}用肠道病毒特异性单克隆抗体,采用改良的免疫组化技术对心肌炎或DCM病人心 肌切片中肠道病毒抗原进行检测,此法直接证明了心肌炎或DCM病人体内确实有子代病毒产 生.但是,肠道病毒究竟通过怎样的机制引起心肌损伤还未阐明,推测可能有多种机制参与 .本文仅就肠道病毒(柯萨奇病毒B3,CVB3)基因组结构及其基因变异与心肌损伤的关系方面加以综述. 相似文献
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Sebastian “Seb” Striefel 《Applied psychophysiology and biofeedback》1998,23(2):93-106
AAPB and its membership are faced with a number of giant challenges, including but not limited to: (1) the cost savings efforts of third-party payors and managed care organizations; (2) the lack of public awareness of biofeedback and its usefulness; and (3) the lack of sufficient research data on both the effectiveness and efficacy of biofeedback. In spite of these challenges, there are windows of opportunity that have been or which could be created to move biofeedback further into the realm of conventional treatment. We must focus our efforts on working together to: (1) create strategic plans for creating the future of applied psychophysiology and biofeedback; (2) educate all decision makers, including the general public; (3) establish better relationships with other professionals with common interests; (4) conduct more efficacy and effectiveness research; and (5) create a demand for our services so that the public will be more willing to pay for our services out of their own pocket. In order for this to happen, we must stop fighting with each other and direct our energies to productive activities that can change fantasies into realities. 相似文献
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Cristina Represas-Represas Alberto Fernández-Villar Alberto Ruano-Ravi?a Ana Priegue-Carrera Maribel Botana-Rial study group of “Validity of COPD- in non-specialized healthcare settings” 《PloS one》2016,11(1)