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排序方式: 共有827条查询结果,搜索用时 46 毫秒
101.
Hierarchical Zeolite: Catalyst Design by NH4OH Treatment of USY Zeolite (Adv. Funct. Mater. 46/2015) 下载免费PDF全文
Joost Van Aelst Danny Verboekend An Philippaerts Nicolas Nuttens Mert Kurttepeli Elena Gobechiya Mohamed Haouas Sreeprasanth P. Sree Joeri F. M. Denayer Johan A. Martens Christine E. A. Kirschhock Francis Taulelle Sara Bals Gino V. Baron Pierre A. Jacobs Bert F. Sels 《Advanced functional materials》2015,25(46):7244-7244
102.
Olav Benestad Lars Brinck Lennart Emborg Bjarne Juul-Kristensen Alexander Kristiansen Niels I. Meyer Kysti Pulliaine Eivind Selvig Anssi Vaittinen 《Energy Policy》1993,21(12):1225-1236
The concept of a sustainable energy sector has received wide attention since the publication of the Brundtland Report in 1987. This paper analyses the possibilities of establishing by 2010 and 2030 an energy system in the Nordic countries which prevents the critical loads of NOx and SO2 respectively on the most vulnerable Nordic ecological systems being exceeded. In addition, the present concentration of CO2 in the atmosphere should not be significantly exceeded within a time horizon to around 2050. Different scenarios have been investigated in order to analyse the scope for attaining such a sustainable energy development within the limits of existing technologies and known potentials of renewable energy sources. Data on the technologies are available in a special catalogue. 相似文献
103.
Sabine Bertho Ilse Haeldermans Ann Swinnen Wouter Moons Tom Martens Laurence Lutsen Dirk Vanderzande Jean Manca Alessia Senes Annalisa Bonfiglio 《Solar Energy Materials & Solar Cells》2007,91(5):385-389
A new approach is presented in order to improve the thermal stability of polymer: [6-6]-phenyl C61 butyric acid methyl ester (PCBM) bulk heterojunction solar cells. The central idea in this approach is the use of a polymer with high glass transition temperature (Tg), well above the normal operating temperatures of the devices. In this paper, a PPV-derivative with a Tg of 150 °C was used as an electron donor and the thermal stability of the obtained solar cells was compared with solar cells based on the reference material poly[2-methoxy-5-(3′,7′-dimethyloctyloxy)-1,4-phenylene vinylene] (MDMO-PPV) with a Tg of 45 °C. The use of the material with higher glass transition temperature resulted in a significant improvement of the thermal stability of the photovoltaic parameters. Furthermore, a systematic transmission electron microscope (TEM) study demonstrates that the better thermal stability of performance coincides with a more stable active layer morphology. Both improvements are attributed to the reduced free movement of the electron donor material (PCBM) within the active layer of the solar cell. 相似文献
104.
Ellen Mosleth Frgestad Nina E Solheim Flte Ellen Merethe Magnus Kristin Hollung Harald Martens Anne‐Kjersti Uhlen 《Journal of the science of food and agriculture》2004,84(8):877-886
The storage protein composition from the Glu‐1, Glu‐3 and Gli‐1 loci encoding high and low molecular weight glutenin subunits (HMW‐GS and LMW‐GS) and gliadins, respectively, was determined on 30 wheat (T aestivum L) genotypes from three growing seasons. The gliadins and the LMW‐GS were identified as gliadin/LMW‐GS pairs. All samples were analysed by two one‐dimensional electrophoretic techniques, and selected samples were also subjected to two‐dimensional electrophoretic separation. Different statistical/data‐analytical techniques were evaluated in the study of how the presence or absence of the protein alleles, the protein content and the growing seasons are related to flour quality. The year of growth had a large impact on mixograph peak time. When predicting mixograph peak time from the presence or absence of significant proteins and the year of growth, 70% of the variability in mixograph peak time could be explained, whereas only 49% of the variability could be explained when the year of growth was deleted from the model. Protein had no effect on mixograph peak time as expected, and the well‐known positive effect of HMW‐GS 5 + 10, and the negative effects of 2 + 12 and 6 + 8 was observed. Furthermore, some of the gliadin/LMW‐GS combinations influenced mixograph peak time significantly. The gliadin/LMW‐GS at the combined Gli‐A1, Glu‐A3 loci b; ?? was positively related to mixograph peak time, whereas ??; ?? and a;a was negatively related. Although the LMW‐GS component ?? of the alleles b; ?? and ??; ?? alleles appear similar on one‐dimensional gels, two‐dimensional separation of selected samples may suggest that the ?? components in these alleles are different proteins. Cross‐validated partial least squares regression combined with empirical uncertainty estimates (jack‐knifing) of the parameters estimated in the model, gave similar results to ANOVA in identifying quality related protein alleles. The applicability of the multivariate approach in proteomics is, however, much wider. Copyright © 2004 Society of Chemical Industry 相似文献
105.
Determination of loratadine and pheniramine from human serum by gas chromatography-mass spectrometry
J Martens 《Canadian Metallurgical Quarterly》1995,673(2):183-188
PURPOSE: To report initial experiences with stent implantation in the treatment of native and recurrent aortic coarctation in adults. METHODS: Two adult patients were diagnosed with aortic coarctation: in one, the native aorta was involved, and in the other, the stenosis involved a prior coarctation repair. Both patients were offered and selected angioplasty with possible stent implantation as an alternative to surgery. RESULTS: In the patient with recurrent narrowing, thrombolysis and balloon dilation preceded the successful deployment of three Palmaz stents along the grafted segment. In the case of native disease, one Palmaz stent was implanted primarily at the site of a critical, focal stenosis. No complications were encountered, and recovery was uneventful. Follow-up at 12 and 6 months, respectively, showed sustained clinical improvement with resolution of symptoms and excellent hemodynamic values. CONCLUSIONS: The positive outcome in these early cases supports further evaluation of the efficacy of adjunctive or primary stenting for treatment of native or recurrent aortic coarctation in adults. 相似文献
106.
D Declerck F Vinckier S Gizani L Martens L Marks G Goffin 《Canadian Metallurgical Quarterly》1995,50(3):9-24
In general, handicapped 12-year old do not show statistical relevant differences with non-handicapped age-matched children in Flanders regarding general caries prevalence, caries distribution and total caries experience. However, important differences were found for the restorative index showing a higher caries treatment need in handicapped children. When the results were analysed according to the type of handicapping condition, it was seen that children with borderline and mild mental handicap and children with speech-, language and/or learning difficulties show the most unfavorable picture. They have a high caries prevalence and caries experience and a low restorative index. Additional analysis of the results can throw some light on the presence of additional caries risk indicators and contributing caries risk factors. 相似文献
107.
Formation of octa- and heptachlorodibenzo-p-dioxins during semi anaerobic digestion of sewage sludge
C Klimm KW Schramm B Henkelmann D Martens A Kettrup 《Canadian Metallurgical Quarterly》1998,37(9-12):2003-2011
Octa- and heptachlorodibenzo-p-dioxins (OCDD and HpCDD) were formed during semi anaerobic digestion of sewage sludge at low temperature (20 degrees C). A twofold increase of OCDD and HpCDD was found after a digestion period of 192 days even if concentrations were corrected by corresponding accumulation factors caused by the degradation of biomass. Other polychlorinated dibenzo-p-dioxins and furans (PCDD/F) and polychlorinated biphenyls (PCB) were not increased. Under strictly anaerobic and aerobic conditions, however, no OCDD and HpCDD were formed. Semi anaerobic formation of OCDD and HpCDD may explain the prevalence of higher chlorinated PCDD in the homologues pattern typical for sewage sludge. 相似文献
108.
An investigation was made on whether the optimal number of tubes in a dry-expansion evaporator, for a given area or a given cost, will change when R22 is replaced with the non-azeotropic mixture R407C. A comprehensive computer program was used to simulate the tube-and-shell evaporator, under several sets of conditions. The simulations show that there are only small differences between R22 and R407C in the optimal number of tubes. However, the results indicate that one can allow a somewhat higher pressure drop for R407C, and that the number of tubes for a given area therefore can be smaller when R407C is used. For both fluids, the evaporator performance is more sensitive to the optimization for a given cost than for a given area. 相似文献
109.
JW Martens M Verhoef-Post N Abelin M Ezabella SP Toledo HG Brunner AP Themmen 《Canadian Metallurgical Quarterly》1998,12(6):775-784
Leydig cell hypoplasia (LCH) is characterized by a decreased response of the Leydig cells to LH. As a result, patients with this syndrome display aberrant male development ranging from complete pseudohermaphroditism to males with micropenis but with otherwise normal sex characteristics. We have evaluated three brothers with a mild form of LCH. Analysis of their LH receptor (LHR) gene revealed a homozygous missense mutation resulting in a substitution of a lysine residue for a isoleucine residue at position 625 of the receptor. In vitro analysis of this mutant LHR, LHR(I625K), in HEK293 cells indicated that the signaling efficiency was significantly impaired, which explains the partial phenotype. We have compared this mutant LHR to two other mutant LHRs, LHR(A593P) and LHR(S616Y), identified in a complete and partial LCH patient, respectively. Although the ligand-binding affinity for all three mutant receptors was normal, the hormonal response of LHR(A593P) was completely absent and that of LHR(S616Y) and LHR(I625K) was severely impaired. Low cell surface expression explained the reduced response of LHR(S616Y), while for LHR(I625K) this diminished response was due to a combination of low cell surface expression and decreased coupling efficiency. For LHR(A593P), the absence of a reduced response resulted from both poor cell surface expression and a complete deficiency in coupling. Our experiments further show a clear correlation between the severity of the clinical phenotype of patients and overall receptor signal capacity, which is a combination of cell surface expression and coupling efficiency. 相似文献
110.
Time-frequency parameters of heart-rate variability 总被引:1,自引:0,他引:1
van Steenis H.G. Martens WLJ Tulen J.H.M. 《IEEE engineering in medicine and biology magazine》2002,21(4):46-58
We have evaluated a new method to compute time-frequency parameters from cardiovascular time series. Apart from calculating the IA and the IF, characteristics of the oscillatory and irregular periods can be quantified that may be relevant to further unravel the situational- and state-dependent dynamics of homeostatic cardiovascular control processes. As a first approach, the method was applied to describe changes in time-frequency parameters and in the characteristics of the oscillatory and irregular periods from supine to standing posture, under steady-state conditions in healthy subjects. The parameters and characteristics discriminated differentially between supine rest and orthostatic challenge. Furthermore, the method can be applied to other cardiovascular time series provided they are monocomponent. 相似文献