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131.
Jae Eun Oh Juhyuk Moon Mauricio Mancio Simon M. Clark Paulo J.M. Monteiro 《Cement and Concrete Research》2011,(1):107-112
Synthetic basic sodalite, Na8[AlSiO4]6(OH)2·2H2O, cubic, P43n, (also known as hydroxysodalite hydrate) was prepared by the alkaline activation of amorphous aluminosilicate glass, obtained from the phase separation of Class F fly ash. The sample was subjected to a process similar to geopolymerization, using high concentrations of a NaOH solution at 90 °C for 24 hours. Basic sodalite was chosen as a representative analogue of the zeolite precursor existing in Na-based Class F fly ash geopolymers. To determine its bulk modulus, high-pressure synchrotron X-ray powder diffraction was applied using a diamond anvil cell (DAC) up to a pressure of 4.5 GPa. A curve-fit with a truncated third-order Birch–Murnaghan equation of state with a fixed K'o = 4 to pressure-normalized volume data yielded the isothermal bulk modulus, Ko = 43 ± 4 GPa, indicating that basic sodalite is more compressible than sodalite, possibly due to a difference in interactions between the framework host and the guest molecules. 相似文献
132.
Clark M Welch 《Coloration Technology》1992,22(1):32-41
Durable-press finishing agents that neither contain nor release formaldehyde when applied to cotton fabrics are reviewed and compared with conventional N-methylolamides in regard to fabric wrinkle resistance, smooth drying properties, strength retention and yellowing imparted. The need for agents that are not derived from formaldehyde results from international recognition that formaldehyde is a probable human carcinogen. When formaldehyde-free cellulose crosslinking agents are screened to eliminate those having toxicity, odour and environmental problems of their own, the most likely candidates are seen to be polycarboxylic acids and 1,3-dimethyl-4, 5-dihydroxy-ethyleneurea (also known as DHDMI). These differ in cost and effectiveness, and will require further research and development to become fully practical. 相似文献
133.
Dixiong Wang Michael B. Clark Jr Susan Trolier‐McKinstry 《Journal of the American Ceramic Society》2018,101(8):3443-3451
Low‐temperature processed bismuth niobate (BNO) thin films were explored in this work as a potential candidate for high‐energy density capacitors. The BNO samples were fabricated by the chemical solution deposition method followed by a series of ultraviolet (UV) exposure and heat treatments. A UV treatment prior to the final pyrolysis step was found to be useful in eliminating bound carbon. X‐ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS) demonstrated that the residual carbon could be effectively removed at 350°C after UV exposure. Following a heat treatment at 450°C, the energy storage density of the BNO thin film reached 39 J/cm3 with an efficiency of 72%. Furthermore, 350°C and 375°C treated BNO samples showed high‐temperature stability such that the efficiencies of the films remained above 97% up to 150°C at 10 kHz under 1 MV/cm applied field. 相似文献
134.
Alvaro J. Romera Gil Levy Pierre C. Beukes Dave A. Clark Chris B. Glassey 《Nutrient Cycling in Agroecosystems》2012,92(3):329-346
On New Zealand dairy farms, it is the nitrogen excreted directly onto pasture, particularly urine, that drives nitrogen (N) leaching from the farm. A new framework (UPF: Urine Patch Framework) is presented that post-processes the results of a whole farm model and runs a mechanistic soil model to simulate the urine patches. Two alternative methods to simulate the spatial distribution of urine patches were implemented and compared (Grid: spatially explicit, and Probabilistic: based on the probability of different temporal urination patterns). This paper describes the implementation of these two methods in connection with a Whole Farm Model; and compares the N leaching predictions with observed data. Two examples are provided, one analyzing the impact of urine patch overlap and another, the relative risk of N leaching at different times of urinary N deposition. The model showed good correlation and predictive ability between simulated annual N leaching results and observed data [R2 = 94 %, mean relative prediction error (MRPE) = 10 % for Grid and R2 = 72 %, MRPE = 20 % for Probabilistic]. The two methods produced similar results across an 8-year period for monthly and annual N leaching (R2 = 96 %, MRPE = 10 % and R2 = 86 %, MRPE = 8 %; respectively). Only 8 % of the paddock area was covered with multiple urinations during 1 year, but as much as 39 % of the total urine volume was deposited on overlapped patches. Systematically removing all urinary N for 1 month in either May or June reduced N leaching by approximately 20 %. Avoiding urinary N deposition during autumn or early winter could be highly effective in mitigating N leached during the following winter. 相似文献
135.
136.
Jian Gao De Tao Zheng Nabil Gindy Doug Clark 《The International Journal of Advanced Manufacturing Technology》2005,26(4):405-414
It is important for a feature-based system to preserve feature integrity during feature operation, especially when feature interaction occurs. The paper presents a feature conversion approach to convert design features used in a design model into machining features for the downstream applications. This process includes both form features (geometric information) and non-geometric features conversion. Most researchers have concentrated on geometric information extraction and conversion without tackling the important problem of non-geometric feature information. This paper focuses on the extraction and conversion of feature geometric dimensions and tolerances (GD&T) for downstream machining application.The main barrier to the integration of a feature-based CAD/CAPP/CAM system – feature interaction – is discussed in this paper, which alters design features in their geometries and non-geometric information. How to identify and validate these feature dimensions and tolerances is one of the key issues in feature interaction conversion. The development of robust methodologies for preserving feature integrity for use in process planning application is the main thrust of the work reported in this paper. 相似文献
137.
Matthias Hennemann Dr. Arno Friedl Dr. Mario Lobell Dr. Jörg Keldenich Dr. Alexander Hillisch Dr. Timothy Clark Prof. Dr. Andreas H. Göller Dr. 《ChemMedChem》2009,4(4):657-669
CypScore predicts the reactivity of competing positions in the same and different molecules to a variety of cytochrome P450 metabolic reactions on a single reactivity scale.
138.
Yusuf Tanrikulu Ewgenij Proschak Dr. Tim Werner Tim Geppert Nickolay Todoroff Alexander Klenner Tim Kottke Kerstin Sander Erich Schneider Dr. Roland Seifert Prof. Dr. Holger Stark Prof. Dr. Timothy Clark Prof. Dr. Gisbert Schneider Prof. Dr. 《ChemMedChem》2009,4(5):820-827
A new pseudoreceptor modeling method (PRPS) was applied to the refinement of a homology model of the human histamine H4 receptor (H4R), the prediction of a ligand binding site, and virtual screening. Retrieval of two new H4R ligands demonstrates the biological relevance of the pseudoreceptor model and provides a means for finding new hits and leads in the early phases of drug discovery.
139.
Rafael Luque Sushanta K. Badamali James H. Clark Macarena Fleming Duncan J. Macquarrie 《Applied Catalysis A: General》2008,341(1-2):154-159
A smart and greener microwave approach to the selective oxidation of cyclohexene is reported whereby, depending on the reaction conditions, the epoxide (65% conversion, 75% selectivity), the enol (70% conversion, 80% selectivity) or the enone (>99% conversion, 89% selectivity) can be obtained in a short period of time ranging from 1 to 20 min. A cobalt-salen-SBA-15 material was employed as catalyst. The reported solventless microwave protocol was simple, greener and more efficient compared to any other reported cyclohexene oxidations. 相似文献
140.