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排序方式: 共有222条查询结果,搜索用时 15 毫秒
51.
Yulia Galagan Yu-Ching Huang Sergey Nedilko Wei-Fang Su 《Journal of the American Ceramic Society》2007,90(8):2673-2675
A novel facile technique to prepare composite materials based on superconducting ceramics (Bi2 Sr2 CaCu2 O x ) and an acrylate polymer matrix has been developed. The polymer does not have a negative effect on the superconductivity properties of the ceramics. The interpenetrating three-dimensional polymeric network formed within ceramics improves its environmental stability. 相似文献
52.
The authors reviewed recent quantitative genetic research on learning disabilities that led to the conclusion that genetic diagnoses differ from traditional diagnoses in that the effects of relevant genes are largely general rather than specific. This research suggests that most genes associated with common learning disabilities--language impairment, reading disability, and mathematics disability--are generalists in 3 ways. First, genes that affect common learning disabilities are largely the same genes responsible for normal variation in learning abilities. Second, genes that affect any aspect of a learning disability affect other aspects of the disability. Third, genes that affect one learning disability are also likely to affect other learning disabilities. These quantitative genetic findings have far-reaching implications for molecular genetics and neuroscience as well as psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
Jennifer M. Smith Yulia M. Serebrennikova Debra E. Huffman German F. Leparc Luis H. García‐Rubio 《加拿大化工杂志》2008,86(5):947-959
The physical and chemical changes occurring in blood as a consequence of microbial activity can be used as quantitative indicators of the presence of microorganisms in blood cultures. This paper reports on the theoretical analysis and computer simulation of the changes in the physical and chemical properties of blood expected as a result of the presence of microorganisms and explores the possibilities of spectrophotometric systems for the early detection of pathogens. It is concluded that multi‐wavelength reflectance methods are suitable and that the approach reported herein can lead to considerable simplifications and cost reduction of blood culture systems. 相似文献
54.
55.
Narendra Kumar Päivi Mäki-Arvela Sara Faten Diáz Atte Aho Yulia Demidova Johan Linden Anna Shepidchenko Mikko Tenhu Jarno Salonen Pekka Laukkanen Alexander Lashkul Johnny Dahl Iliya Sinev Anne-Riikka Leino Krisztian Kordas Tapio Salmi Dmitry Yu. Murzin 《Topics in Catalysis》2013,56(9-10):696-713
Fe-modified mordenite, ferrierite, Y, ZSM-5, ZSM-12 and beta zeolite catalysts were prepared by solid state ion-exchange and conventional liquid phase ion-exchange methods from aqueous solutions. Sn- modified H-beta-300 zeolite catalyst was prepared by the later method. The characterization of proton form, Fe and Sn modified zeolites was carried out using X-ray powder diffraction, scanning electron microscopy, Mössbauer spectroscopy with magnetic measurements, transmission electron microscopy, nitrogen adsorption, X-ray absorption spectroscopy, X-ray photoelectron spectroscopy, inductively coupled plasma spectroscopy, thermo-gravimetric analysis and FTIR spectroscopy using pyridine as a probe molecule. Isomerization of α-pinene oxide over the Fe and Sn modified zeolite catalysts was carried out in the liquid phase using a batch-wise glass reactor. Formation of campholenic aldehyde and fencholenic aldehyde were observed to be influenced by the structure, acidity of zeolite and contents of Fe and Sn, reaction temperature and the catalysts pretreatment. 相似文献
56.
57.
Yulia V. Gerasimova Dr. Evan Cornett Dmitry M. Kolpashchikov Dr. 《Chembiochem : a European journal of chemical biology》2010,11(6):811-817
Along with biocompatibility, chemical stability, and simplicity of structural prediction and modification, deoxyribozyme‐based molecular sensors have the potential of an improved detection limit due to their ability to catalytically amplify signal. This study contributes to the understanding of the factors responsible for the limit of detection (LOD) of RNA‐cleaving deoxyribozyme sensors. A new sensor that detects specific DNA/RNA sequences was designed from deoxyribozyme OA‐II [Chiuman, W.; Li, Y. (2006) J. Mol. Biol. 357, 748–754]. The sensor architecture allows for a unique combination of high selectivity, low LOD and the convenience of fluorescent signal monitoring in homogeneous solution. The LOD of the sensor was found to be ~1.6×10?10 M after 3 h of incubation. An equation that allows estimation of the lowest theoretical LOD using characteristics of parent deoxyribozymes and their fluorogenic substrates was derived and experimentally verified. According to the equation, “catalytically perfect” enzymes can serve as scaffolds for the design of sensors with the LOD not lower than ~2×10?15 M after 3 h of incubation. A new value termed the detection efficiency (DE) is suggested as a time‐independent characteristic of a sensor's sensitivity. The expressions for the theoretical LOD and DE can be used to evaluate nucleic acid and protein enzymes for their application as biosensing platforms. 相似文献
58.
Yulia R. Gel 《Computational statistics & data analysis》2010,54(4):958-965
Over the last decade there has been a marked interest in a Laplace distribution and its properties and generalizations, especially in the framework of financial applications. Such an interest has led to a revision and discussion of available goodness-of-fit procedures for a Laplace distribution. Indeed, since most of the studies which employ the Laplace distribution are concerned with modelling heavy tailed patterns, the modern class of possible alternatives is way broader than just testing the Laplace vs. normal distribution. In this paper we propose a new test of fit for a Laplace distribution against deviations with heavier tails than that of the reference Laplace distribution. The proposed goodness-of-fit procedure is based on sample skewness and kurtosis and a robust L1 estimator of scale about a sample median. The developed test statistic is shown to asymptotically follow a χ2-distribution with two degrees of freedom. Performance of the new goodness-of-fit test is illustrated by simulations and a case study. 相似文献
59.
Dechan Angmo Irene Gonzalez‐Valls Sjoerd Veenstra Wiljan Verhees Subarna Sapkota Sebastian Schiefer Birger Zimmermann Yulia Galagan Jorgen Sweelssen Monica Lira‐Cantu Ronn Andriessen Jan M. Kroon Frederik C. Krebs 《应用聚合物科学杂志》2013,130(2):944-954
Five different indium‐tin‐oxide free (ITO‐free) polymer solar cell architectures provided by four participating research institutions that all presented a laboratory cell performance sufficient for use in mobile and information and communication technology (ICT) were evaluated based on photovoltaic performance and lifetime tests according to the ISOS protocols. The comparison of the different device architectures was performed using the same active material (P3HT: PCBM) and tested against an ITO‐based reference device. The active area was 1 cm2 and rigid glass or flexible polyester substrates were employed. The performance results were corroborated by use of a round robin methodology between the four participating laboratories (DTU/DK, ECN/NL, Frauenhofer ISE/DE, and the Holst Centre/NL), while the lifetime testing experiments were carried out in only one location (DTU). Five different lifetime testing experiments were carried out for a minimum of 1000 h: (1) shelf life (according to ISOS‐D‐1); (2–3) stability under continuous 1 sun illumination (1000 Wm?2, AM1.5G) at low (37 ± 3°C) and high (80 ± 5°C) temperatures (according to ISOS‐L‐1 and ISOS‐L‐2); (4) stability under continuous low‐light conditions at 0.1 sun (100 Wm?2, AM1.5G, 32°C) (according to ISOS‐LL); (5) continuous illumination (670 Wm?2, AM1.5G) at high temperature (65°C) and high humidity (50% RH) (according to ISOS‐L‐3). Finally, the upscaling compatibility of these device architectures based on the device photovoltaic behavior, stability and scalability were identified and we confirm that an architecture that presents a high score in only one aspect of the solar cell performance is not sufficient to justify an investment in upscaling. Many will require further technical development. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 944‐954, 2013 相似文献
60.
Anja Thust Yulia Arinicheva Eiken Haussühl Javier Ruiz‐Fuertes Lkhamsuren Bayarjargal Sven C. Vogel Stefan Neumeier Björn Winkler 《Journal of the American Ceramic Society》2015,98(12):4016-4021
Synthetic La1?xEuxPO4 monazite‐type ceramics with 0 ≤ x ≤ 1 have been characterized by ultrasound techniques, dilatometry, and micro‐calorimetry. The coefficients of thermal expansion and the elastic properties are, to a good approximation, linearly dependent on the europium concentration. Elastic stiffness coefficients range from 182(1) to 202(1) GPa for c11 and from 53.8(7) to 61.1(4) GPa for c44. They are strongly dependent on the density of the sample. The coefficient of thermal expansion at 673 K is 8.4(3) × 10?6 K?1 for LaPO4 and 9.9(3) × 10?6 K?1 for EuPO4, respectively. The heat capacities at ambient temperature are between 101.6(8) J·(mol·K)?1 for LaPO4 and 110.1(8) J·(mol·K)?1 for EuPO4. The difference between the heat capacity of LaPO4 and the Eu‐containing solid solutions is dominated by electronic transitions of the 4f‐electrons at temperatures above 75 K. 相似文献