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121.
James W. Gentry Richard V. Calabrese 《Particle & Particle Systems Characterization》1986,3(3):104-110
A procedure for estimating the effectiveness of algorithms which retrieve size distribution parameters from cumulative fractions or moments is described. The principle of the algorithm is to select moments, or cumulative fractions, which minimize the condition number. Extensive tests of the algorithm for a distribution consisting of the sum of two log normal distributions were carried out. This procedure can be easily extended to use different numbers and types of constituent functions. The simulations indicated that moment methods which include positive and negative moments give the best result. When the means of the constituent distribution are close, the large condition numbers indicate that no algorithm will give unambiguous values for the parameters. 相似文献
122.
123.
Ubbrìaco P. Bruno P. Traini A. Calabrese D. 《Journal of Thermal Analysis and Calorimetry》2001,66(1):293-305
In this study the process of hydration of fly ash, produced by a municipal solid waste (MSW) incinerator, is examined in water
and in a solution enriched with Ca(OH)2. The examined fly ash samples are characterized by a high content of alkaline chlorides and anhydrite and by remarkable amounts
of heavy metals. Investigations using differential thermal analysis/thermogravimetry (DTA/TG) and X-ray diffractometry (XRD)show
particular kinetics of the formation of the ettringite phase. The development of such a hydrated phase is much more intense
in the presence of an excess of Ca(OH)2so as to consume the ‘free’ sulphate in the case of the more reactive fly ash. Experimental results from thermal analysis
and X-ray diffractometry show the presence of different hydrated phases during the interaction between fly ash and aqueous
solution. The analytical determinations, related to the aqueous solution, point out an interesting decrease in concentration
of metals Pb, Zn and Cr(VI), relating to the middle period of the interaction.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
124.
Thomas H. Newman Joseph C. Calabrese Richard T. Oakley David A. Stanislawski Robert West 《Journal of organometallic chemistry》1982,225(1):211-224
The heterocyclic diphosphasilanes (PhP)2(SiMe2)n(n - 2, 3, 4) were synthesized by the reactions of 1, 2-dilithium-1, 2-diphenyldiphosphide with α, ω-dichloropermethylpolysilanes Cl(SiMe2)nCl (n - 2, 3, 4). Stereochemical fluxionality in these compounds was examined by dynamic nuclear magnetic resonance. The1H, 13C, 31P and29Si NMR spectra are reported and discussed in terms of a phosphorus inversion mechanism. Values of the free energy of activation for phosphorous inversion are reported for (PhP)2(SiMe2)n (n - 3, 4) and compared with related compounds.A single-crystal X-ray structure analysis has been carried out on (PhP)2-(SiMe2)3. The material crystallizes in the monoclinic space groupP21/c with four molecules per unit cell. The cell dimensions area - 12.526(11)A?, b - 11.828(10)A?, c - 15.412(7)A?and β - 103.56(6)°. The molecule exists in thedl (trans) form with the five-membered ring significantly twisted. The angle between the phosphorus-phosphorus bond and the plane of the three silicon atoms is 42.9°. 相似文献
125.
Armstrong TA Bettoni D Bharadwaj V Biino C Borreani G Broemmelsiek D Buzzo A Calabrese R Ceccucci A Cester R Church MD Dalpiaz P Dalpiaz PF Dibenedetto R Dimitroyannis D Fabbri MG Fast JE Gianoli A Ginsburg CM Gollwitzer KE Hahn AA Hasan MA Hsueh SY Lewis RA Luppi E Macrí M Majewska A Mandelkern MA Marchetto F Marinelli M Marques JL Marsh W Martini M Masuzawa M Menichetti E Migliori A Mussa R Palestini S Pallavicini M Pastrone N Patrignani C Peoples J Pesando L Petrucci F Pia MG Pordes S 《Physical review letters》1993,70(9):1212-1215
126.
Teresa Gervasi Vito Pellizzeri Giorgio Calabrese Giuseppa Di Bella Giacomo Dugo 《Natural product research》2018,32(6):648-653
Food waste is the single-largest component of the waste stream, in order to protect and safeguard the public health, useful and innovative recycling methods are investigated. The conversion of food wastes in value-added products is becoming a more economically viable and interesting practice. Food waste, collected in the distribution sector and citrus industries, was characterised for its potential as a raw material to use in fermentation processes. In this study, the production of single-cell protein (SCP) using food waste as a substrate was investigated. The purpose of this study has been to produce SCP from mixtures of food waste using Saccharomyces cerevisiae. The main fermentation test was carried out using a 25 l bioreactor. The utilisation of food waste can allow us to not only to reduce environmental pollution, but also to obtain value-added products such as protein supply for animal feed. 相似文献
127.
Böhm A Vazquez C McLean RS Calabrese JC Kalm SE Manson JL Epstein AJ Miller JS 《Inorganic chemistry》1996,35(11):3083-3088
(meso-Tetrakis(3,5-di-tert-butyl-4-hydroxyphenyl)porphinato)manganese(III) tetracyanoethenide, [MnTP'P][TCNE], has been structurally and magnetically characterized. [MnTP'P][TCNE] (C(96)H(108)MnN(8)O(4)) belongs to the triclinicP&onemacr; (No. 2) space group with a = 8.597(2) ?, b = 14.756(4) ?, c = 17.573(5) ?, alpha = 101.16 (2) degrees, beta = 100.56(2) degrees, gamma = 96.37(2) degrees, and Z = 1. Due to the oxidative instability of the phenoxy groups, [Mn(III)TP'P][TCNE] was prepared from the reaction of [Mn(III)TP'P]OAc with the strong acid H(2)TCNE (pK(a) = 3.6) in the presence of TCNE to form acetic acid and the product. [MnTP'P][TCNE] is a coordination polymer with the Mn(III) sites bridged by trans-&mgr;(2)-bound [TCNE](*)(-) with relatively short (8.587 ?) intrachain and long (>/=14.756 ?) interchain Mn.Mn separations. The magnetic data above 210 K obey the Curie-Weiss expression with an effective Θ value of 90.0 K, the largest yet reported for a soluble molecule-based magnet. In addition to a 15 K T(c) hysteretic behavior with a coercive field of 100 Oe is observed at 5 K. Despite the significant steric bulk leading to the substantially decreased interchain interactions that are crucial for magnetic ordering, the T(c) is unexpectedly high and suggests that other linear chain systems may be expected to exhibit magnetic ordering at higher temperatures. 相似文献
128.
129.
Pitarresi G Tripodo G Calabrese R Craparo EF Licciardi M Giammona G 《Macromolecular bioscience》2008,8(10):891-902
Inulin was chosen as a starting polymer for biocompatible, pH-sensitive and biodegradable hydrogels. Three INUDVSA-TT hydrogels were obtained by crosslinking inulin derivatives with trimethylolpropane tris(3-mercaptopropionate) under varying conditions. The resulting hydrogels were cell compatible, as demonstrated by MTS and trypan blue exclusion assays acting on Caco-2 cells, and were biodegraded by inulinase and esterase, thus suggesting their use as colonic drug delivery systems. 2-Methoxyestradiol, an anti-cancer drug, was soaked in INUDVSA-TT hydrogels and its in vitro release and apoptotic effect on Caco-2 cells were evaluated. 相似文献
130.
Paul W. A. Devine Henry C. Fisher Antonio N. Calabrese Fiona Whelan Daniel R. Higazi Jennifer R. Potts David C. Lowe Sheena E. Radford Alison E. Ashcroft 《Journal of the American Society for Mass Spectrometry》2017,28(9):1855-1862
Collision cross-section (CCS) measurements obtained from ion mobility spectrometry-mass spectrometry (IMS-MS) analyses often provide useful information concerning a protein’s size and shape and can be complemented by modeling procedures. However, there have been some concerns about the extent to which certain proteins maintain a native-like conformation during the gas-phase analysis, especially proteins with dynamic or extended regions. Here we have measured the CCSs of a range of biomolecules including non-globular proteins and RNAs of different sequence, size, and stability. Using traveling wave IMS-MS, we show that for the proteins studied, the measured CCS deviates significantly from predicted CCS values based upon currently available structures. The results presented indicate that these proteins collapse to different extents varying on their elongated structures upon transition into the gas-phase. Comparing two RNAs of similar mass but different solution structures, we show that these biomolecules may also be susceptible to gas-phase compaction. Together, the results suggest that caution is needed when predicting structural models based on CCS data for RNAs as well as proteins with non-globular folds. 相似文献