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排序方式: 共有391条查询结果,搜索用时 15 毫秒
1.
Taro Shimonosono Yoshihiro Hirata Mubin Changgan Syohei Kamei Rina Tokaiya Soichiro Sameshima Toshifumi Yoshidome Katsuhiko Yamaji 《Ceramics International》2018,44(8):8904-8912
This paper reports the performance of porous Gd-doped ceria (GDC) electrochemical cells with Co metal in both electrodes (cell No. 1) and with Ni metal in the cathode and Co metal in the anode (cell No. 2) for CO2 decomposition, CH4 decomposition, and the dry reforming reaction of a biogas with CO2 gas (CH4 + CO2 → 2H2 + 2CO) or with O2 gas in air (3CH4 +?1.875CO2 +?1.314O2 → 6H2 +?4.875CO +?0.7515O2). GDC cell No. 1 produced H2 gas at formation rates of 0.055 and 0.33?mL-H2/(min?m2-electrode) per 1?mL-supplied gas/(min?m2-electrode) at 600?°C and 800?°C, respectively, by the reforming of the biogas with CO2 gas. Similarly, cell No. 2 produced H2 gas at formation rates of 0.40?mL-H2/(min?m2) per 1?mL-supplied gas/(min?m2) at 800?°C from a mixture of biogas and CO2 gas. The dry reforming of a real biogas with CO2 or O2 gas at 800?°C proceeded thermodynamically over the Co or Ni metal catalyst in the cathode of the porous GDC cell. Faraday's law controlled the dry reforming rate of the biogas at 600?°C in cell No. 2. This paper also clarifies the influence of carbon deposition, which originates from CH4 pyrolysis (CH4 → C + 2H2) and disproportionation of CO gas (2CO → C + CO2), on the cell performance during dry reforming. The dry reforming of a biogas with O2 molecules from air exhibits high durability because of the oxidation of the deposited carbon by supplied air. 相似文献
2.
Previous studies in children have shown inconsistent, poorly reproducible GH responses to exogenous GH-releasing factor (GRF), with wide individual variability. In the present study, we tested the hypothesis that prior administration of the long-acting somatostatin analog, SMS 201-995 (SMS), will enhance GH responsiveness to a subsequent GRF challenge. Two study protocols were employed in 37 children with short stature [M = 31, F = 6, ages 11.8 +/- 1.6 yr (mean +/- SEM), height -2.25 +/- 0.55 SDS (SD scores)]. In both studies, each subject served as his/her own control. In the first study, which was designed to determine optimal SMS dose and regimen, SMS, in doses ranging from 0.8-2.2 micrograms/kg sc, was randomly administered or omitted at 0800 h after an overnight fast, and a GRF bolus (50 micrograms, iv) was given 4 h later. In the second study, we employed a protocol identical to study 1 except for the use of standard doses of SMS (1 microgram/kg, sc) and GRF (1 microgram/kg, iv) and an additional 1-h delay of the GRF injection. Plasma GH levels were measured every 20 min from 0800 h until 2 h after the GRF injection in both studies. In study 1 (n = 12; M = 10, F = 2), SMS significantly suppressed spontaneous GH secretion (expressed as the mean +/- SEM GH AUC during the 4-h SMS-GRF interval, AUC 1:2.2 +/- 0.4 vs. 6.2 +/- 0.9 micrograms/L.h; P < 0.001), GH responsiveness to GRF (GH AUC during the 2 h after the GRF injection, AUC 2: 41.5 +/- 7.8 vs. 85.0 +/- 13.5 micrograms/L.h; P < 0.001), and the GH peak response (17.4 +/- 3.1 vs. 36.0 +/- 6.2 micrograms/L; P < 0.001), compared to control tests. In contrast, in study 2 (n = 25; M = 21, F = 4), whereas spontaneous GH secretion was still suppressed during the 5-h SMS-GRF interval (AUC 1:3.8 +/- 0.4 vs. 7.4 +/- 1.1 micrograms/L.h; P < 0.001), both the GH peak response (56.7 +/- 5.5 vs. 30.5 +/- 3.0 micrograms/L; P < 0.0001) and the GH AUC (AUC 2: 103.7 +/- 10.3 vs. 77.5 +/- 6.8 micrograms/L.h; P < 0.05) after GRF administration were significantly augmented by pretreatment with SMS, compared to control tests. Taken together, these results indicate that a priming SMS dose of 1 microgram/kg has a significant permissive effect on GH responsiveness to exogenous GRF administered 5 h later.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
3.
Lussier Isabelle; Derevensky Jeffrey L.; Gupta Rina; Bergevin Tanya; Ellenbogen Stephen 《Canadian Metallurgical Quarterly》2007,21(2):165
The study of resilient children has overturned many deficit-focused models concerning the ontogenesis of children raised in adversity. This study explored the relationship between risk and protective factors, resilience, and youth gambling behavior. More specifically, this study examined the relative contribution of various risk and protective domains in relation to problem gambling behavior and examined whether youth identified as resilient (high risk exposure- high internalized protection) were as likely as those identified as vulnerable (high risk exposure-low internalized protection) to engage in excessive gambling behavior. The sample consisted of 1,273 students ages 12 to 19. The findings demonstrated that risk and protective factors each provide a unique contribution to the prediction model of gambling problems. Resilient and vulnerable youth differed significantly in their self-reported gambling severity. As well, resilient youth were not statistically distinguishable from low-risk exposure groups in terms of their gambling severity. Findings are interpreted with respect to resilience and prevention research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Although the basal ganglia have been shown to be critical for the expression of emotion in prosody and facial expressions, it is unclear whether they are also critical for recognition of emotions. Selective pathology of parts of the basal ganglia is a hallmark of individuals with Parkinson's disease, and such patients have been examined in several studies of emotion. We examined 18 patients with Parkinson's disease (11 men, 7 women) and 13 age-, education-, gender ratio-, and IQ-matched normal controls on their ability to recognize emotions signaled by facial expressions. Parkinson's patients performed entirely normally on a quantitative task of recognizing emotional facial expressions. The findings do not support the notion that the sectors of basal ganglia that are dysfunctional in Parkinson's disease are essential for recognizing emotion in facial expressions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
根据1964—2015年辽宁省23个气象站点的逐日平均气温、相对湿度及平均风速资料,采用人体舒适度指数法计算人体舒适度指数,在季尺度上分析辽宁省不同等级舒适日数演变情况及典型旅游城市最佳旅游期;运用旋转经验正交函数分解法(REOF),分析人体舒适度指数季尺度空间变化特征,并应用ArcGIS软件进行舒适区域划分。结果表明:①辽宁省多年平均冷不舒适日数呈降低趋势,舒适日数呈增加趋势,热不舒适日数也呈微弱增加趋势;舒适程度夏季>秋季>春季>冬季;②除冬季外5座典型旅游城市均适宜旅游,夏季为最佳旅游期;其中,沈阳、本溪更适宜春季旅游,大连更适宜秋季旅游。③辽宁省四季舒适度变化情况可大致划分为辽西、辽中、辽东三个区域,具体划分情况随季节有相应变化,总体舒适度由辽宁东部向西部逐渐递减。 相似文献
6.
Blends of sulfonated phenylated polytriphenylene oxide and poly(methyl methacrylate‐co‐4‐vinyl pyridine) were examined by dynamic mechanical, Fourier transform infrared, and NMR techniques. A high degree of miscibility was evident from a single drop in a plot of the storage modulus versus the temperature. The presence of ionic moieties due to proton transfer from sulfonic acid to 4‐vinyl pyridine was confirmed by both NMR and IR spectroscopy studies. The coils were found to be close to one another in dimethyl sulfoxide‐d6 because the aromatic shielding effect of the phenyl rings of the phenylated polytriphenylene oxide units was observed from the upfield shift of most of the protons of poly(methyl methacrylate) in the NMR spectrum. However, the absence of cross peaks in the nuclear Overhauser and exchange spectroscopy experiments suggested that the intermolecular distance between the chains had to be larger than 4 Å. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 728–733, 2003 相似文献
7.
Epoxy nanocomposites reinforced with 0–5 wt% cellulose nanocrystal (CNC) were fabricated by solution casting method. The CNCs were first dispersed in the hardener together with a co-solvent and subsequently mixed with epoxy monomer using two different protocols: bulk mixing and dropwise mixing. The dropwise mixing resulted in more homogeneously-dispersed CNCs and provided better mechanical properties, particularly higher tensile strength, tensile modulus, and work of fracture with increasing CNC content. Investigation of various CNC/hardener mixtures with different solvent content showed that the residual solvent in the composite mixture had an impact on the curing behavior of the nanocomposite epoxy and may have lowered its crosslinking density, leading to Tg depression. However, the presence of the solvent was shown to be essential for the preparation of a well-dispersed CNC phase in the hardener solution, and to form homogenous composite mixtures. Our results show that the reinforcement effect due to higher CNC concentration is more significant than the solvent effect in the hardener system and shows greater improvement in mechanical properties. The CNC component reversed the solvent plasticizing effect through its superior mechanical reinforcing effects, and the dropwise mixing process led to better dispersion compared with the bulk mixing process. 相似文献
8.
Jehoon Lee Romeil Sandhu Allen Tannenbaum 《Computer Vision and Image Understanding》2013,117(8):922-933
In this paper, we address the problem of 2D–3D pose estimation. Specifically, we propose an approach to jointly track a rigid object in a 2D image sequence and to estimate its pose (position and orientation) in 3D space. We revisit a joint 2D segmentation/3D pose estimation technique, and then extend the framework by incorporating a particle filter to robustly track the object in a challenging environment, and by developing an occlusion detection and handling scheme to continuously track the object in the presence of occlusions. In particular, we focus on partial occlusions that prevent the tracker from extracting an exact region properties of the object, which plays a pivotal role for region-based tracking methods in maintaining the track. To this end, a dynamical choice of how to invoke the objective functional is performed online based on the degree of dependencies between predictions and measurements of the system in accordance with the degree of occlusion and the variation of the object’s pose. This scheme provides the robustness to deal with occlusions of an obstacle with different statistical properties from that of the object of interest. Experimental results demonstrate the practical applicability and robustness of the proposed method in several challenging scenarios. 相似文献
9.
10.
AND/OR search spaces accommodate advanced algorithmic schemes for graphical models which can exploit the structure of the
model. We extend and evaluate the depth-first and best-first AND/OR search algorithms to solving 0-1 Integer Linear Programs (0-1 ILP) within this framework. We also include a class
of dynamic variable ordering heuristics while exploring an AND/OR search tree for 0-1 ILPs. We demonstrate the effectiveness
of these search algorithms on a variety of benchmarks, including real-world combinatorial auctions, random uncapacitated warehouse
location problems and MAX-SAT instances. 相似文献