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91.
K Sugahara Y Tanaka S Yamada N Seno H Kitagawa SM Haslam HR Morris A Dell 《Canadian Metallurgical Quarterly》1996,271(43):26745-26754
We prepared a series of oligosaccharides from king crab cartilage chondroitin sulfate K after exhaustive digestion with testicular hyaluronidase, and determined the structures of four tetrasaccharides and a pentasaccharide by fast atom bombardment mass spectrometry, high performance liquid chromatography analysis of chondroitinase AC-II digests, and 500-MHz 1H NMR spectroscopy. The tetrasaccharides shared the common core structure GlcAbeta1-3GalNAcbeta1-4GlcAbeta1-3GalNAc with various sulfation profiles. One structure was GlcAbeta1-3GalNAc(4S)beta1-4GlcAbeta1-3GalNAc(4S), whereas three of them have the following hitherto unreported structures including a novel glucuronate 3-O-sulfate: GlcA(3S)beta1-3GalNAc(4S)beta1-4GlcAbeta1-3GalNAc(4S), GlcAbeta1-3GalNAc(4S)beta1-4GlcA(3S)beta1-3GalNAc(4S), and GlcA(3S)beta1-3GalNAc(4S)beta1-4GlcA(3S)beta1-3GalNAc(4S), where 3S or 4S represents 3-O- or 4-O-sulfate, respectively. The structure of the pentasaccharide was determined as GlcA(3S)beta1-3GalNAc(4S)beta1-4GlcA(3S)beta1- 3GalNAc(4S)beta1-4GlcA. Chondroitinase ABC digestion of the tetrasaccharides with GlcA(3S) at the internal position destroyed the disaccharide unit containing GlcA(3S) derived from the reducing side and resulted in only the disaccharide unit from the non-reducing side. In contrast, these tetrasaccharides remained totally resistant to chondroitinase AC-II. The results indicated that it is necessary to reevaluate the disaccharide composition of chondroitin sulfate poly- or oligosaccharides purified from various biological sources, since they were usually determined after chondroitinase ABC digestion. It is probable that the structures containing GlcA(3S) would not have been detected. 相似文献
92.
93.
A. V. Samokhvalov A. S. Mel’nikov A. I. Buzdin 《Journal of Superconductivity and Novel Magnetism》2013,26(9):2851-2852
On the basis of Usadel equations, we consider superconductivity nucleation and Josephson current in multiply connected mesoscopic superconductor/ferromagnet (S/F) hybrids. We demonstrate that the exchange field can provoke an increase in the critical temperature T c of the superconducting transition in the magnetic field. We study the Josephson effect in S/F composites and demonstrate that the negative sign of the critical current (π state) can be realized in such structures despite a dispersion of the distances between different segments of superconducting electrodes. 相似文献
94.
Xing Xing Guangqing Zhang Mark Dell’Amico George Ciezki Qingbo Meng Oleg Ostrovski 《Metallurgical and Materials Transactions B》2013,44(4):870-877
Carbonaceous materials including cokes, chars, and pyrolyzed coals were annealed at temperatures ranging from 973 K to 1773 K (700 °C to 1500 °C) in an inert atmosphere. Macro and microstrengths of original and annealed carbonaceous materials were characterized by the tensile strength and fracture toughness. Fracture toughness was determined for inert maceral-derived component (IMDC) and reactive maceral-derived component (RMDC) using ultramicro indentation. Experimental data obtained by tensile tests were processed using the Weibull statistical method to find “inherent” strength. Tensile strength of chars and coals was significantly increased by annealing at temperatures ranging from 973 K to 1373 K (700 °C to 1100 °C); further increase in annealing temperature to 1773 K (1500 °C) increased their tensile strength only slightly. Tensile strength of cokes decreased with the increasing annealing temperature; the major effect was observed in the temperature range from 1573 K to 1773 K (1300 °C to 1500 °C). Fracture toughness of chars and coals was enhanced significantly by heat treatment at temperatures ranging from 973 K to 1373 K (700 °C to 1100 °C) as a result of pyrolysis, while that of cokes increased slightly by heat treatment. Fracture toughness of IMDC was higher than RMDC. Macrostrength of carbonaceous materials was strongly affected by their porosity and microstrength. The effect of pore geometry on macrostrength was marginal. Decreasing the porosity was more effective compared with increasing the microstrength in improving the macrostrength of carbonaceous materials. 相似文献
95.
65纳米设计时序收敛问题介绍时序收敛一直是当代ASIC设计物理实现的主要问题,特别是对于那些用于通信产品中的ASIC来说更是如此。我们有一项65纳米ASIC就是这种设计。它拥有2400万门数和4400万内存位,大部分逻辑将一直以400MHz 相似文献
96.
Thomas Eglinton Jim Hinkley Andrew Beath Mark Dell’Amico 《JOM Journal of the Minerals, Metals and Materials Society》2013,65(12):1710-1720
The Australian minerals processing and extractive metallurgy industries are responsible for about 20% of Australia’s total greenhouse gas (GHG) emissions. This article reviews the potential applications of concentrated solar thermal (CST) energy in the Australian minerals processing industry to reduce this impact. Integrating CST energy into these industries would reduce their reliance upon conventional fossil fuels and reduce GHG emissions. As CST technologies become more widely deployed and cheaper, and as fuel prices rise, CST energy will progressively become more competitive with conventional energy sources. Some of the applications identified in this article are expected to become commercially competitive provided the costs for pollution abatement and GHG mitigation are internalized. The areas of potential for CST integration identified in this study can be classed as either medium/low-temperature or high-temperature applications. The most promising medium/low-grade applications are electricity generation and low grade heating of liquids. Electricity generation with CST energy—also known as concentrated solar power—has the greatest potential to reduce GHG emissions out of all the potential applications identified because of the 24/7 dispatchability when integrated with thermal storage. High-temperature applications identified include the thermal decomposition of alumina and the calcination of limestone to lime in solar kilns, as well as the production of syngas from natural gas and carbonaceous materials for various metallurgical processes including nickel and direct reduced iron production. Hybridization and integration with thermal storage could enable CST to sustain these energy-intensive metallurgical processes continuously. High-temperature applications are the focus of this paper. 相似文献
97.
Audrey Dell Hammerich J. Gonzalo Muga Ronnie Kosloff 《Israel journal of chemistry》1989,29(4):461-471
Several novel aspects of scattering resonances are studied. An expression, valid for a finite box, relating the continuum phase shift with the energy shift and unperturbed level separation is proposed and applied to obtain the resonance parameters. The effect of the resonance on propagating a wavepacket in imaginary time is studied. It is observed that the resonance strongly affects the cumulants of the energy distribution. In particular, a local minimum of the first derivative of the energy with respect to time (proportional to the second cumulant) serves to estimate the resonance energy and wavefunction. Once the estimate is known, the autocorrelation function is used to evaluate the resonance width. Alternatively, a new iterative approach is developed that is capable of selectively yielding an arbitrary band of energy eigenvalues and eigenfunctions on a grid. This method is applied to give those energy levels that are of interest for the discrete computation of the resonant phase shift, i.e., those close to resonance. Exact (analytical) and approximate results are in good agreement for a particular separable potential model in one dimension. These methods can be extended to realistic potentials in higher dimensions. 相似文献
98.
99.
Maria Dolores Pastor Ana Nogal Sonia Molina-Pinelo Ricardo Meléndez Beatriz Romero-Romero Maria Dolores Mediano Jose L. López-Campos Rocío García-Carbonero Amparo Sanchez-Gastaldo Amancio Carnero Luis Paz-Ares 《International journal of molecular sciences》2013,14(2):3440-3455
Lung cancer (LC) and chronic obstructive pulmonary disease (COPD) commonly coexist in smokers, and the presence of COPD increases the risk of developing LC. Cigarette smoke causes oxidative stress and an inflammatory response in lung cells, which in turn may be involved in COPD and lung cancer development. The aim of this study was to identify differential proteomic profiles related to oxidative stress response that were potentially involved in these two pathological entities. Protein content was assessed in the bronchoalveolar lavage (BAL) of 60 patients classified in four groups: COPD, COPD and LC, LC, and control (neither COPD nor LC). Proteins were separated into spots by two dimensional polyacrylamide gel electrophoresis (2D-PAGE) and examined by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF/TOF). A total of 16 oxidative stress regulatory proteins were differentially expressed in BAL samples from LC and/or COPD patients as compared with the control group. A distinct proteomic reactive oxygen species (ROS) protein signature emerged that characterized lung cancer and COPD. In conclusion, our findings highlight the role of the oxidative stress response proteins in the pathogenic pathways of both diseases, and provide new candidate biomarkers and predictive tools for LC and COPD diagnosis. 相似文献
100.
Jane L. O’Dell Charles R. Frihart 《Journal of Adhesion Science and Technology》2013,27(18-19):2027-2042
We studied the high temperature performance of soy meal processed to different protein concentrations (flour, concentrate, and isolate), as well as formulated soy-based adhesives, and commercial nonsoy adhesives for comparison. No thermal transitions were seen in phenol-resorcinol-formaldehyde (PRF) or soy-phenol-formaldehyde (SoyPF) or in as-received soy flour adhesive during differential scanning calorimetry scans heating at 10?°C/min between 35 and 235?°C. Heat flow rates decreased in the order soy flour (as received)?>?SoyPF?>?PRF?>?emulsion polymer isocyanate (EPI). In thermogravimetric analysis (TGA) scans from 110 to 300?°C at 2?°C/min, total weight loss decreased in the order soy flour (as-received)>SoyPF?>?PRF?>?casein?>?maple?>?EPI. For bio-based materials, the total weight loss (TGA) decreased in the order soy flour (as-received) > concentrate, casein?>?isolate. Dynamic mechanical analysis from 35 to 235?°C at 5?°C/min of two veneers bonded by cured adhesive showed 30–40% decline in storage modulus for maple compared to 45–55% for the adhesive made from soy flour in water (Soy Flour) and 70–80% for a commercial poly(vinyl acetate) modified for heat resistance. DMA on glass fiber mats showed thermal softening temperatures increasing in the order Soy Flour?<?casein?<?isolate?<?concentrate. We suggest that the low molecular weight carbohydrates plasticize the flour product. When soy-based adhesives were tested in real bondlines in DMA and creep tests in shear, they showed less decrease in storage modulus than the glass fiber-supported specimens. This suggests that interaction with the wood substrate improved the heat resistance property of the adhesive. Average hot shear strengths (ASTM D7247) were 4.6 and 3.1?MPa for SoyPF and Soy Flour compared to 4.7 and 0.8?MPa for PRF and EPI and 4.7 for solid maple. As a whole, these data suggest that despite indications of heat sensitivity when tested neat, soy-based adhesives are likely to pass the heat resistance criterion required for structural adhesives. 相似文献