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121.
Bianca Ciui Daliborka Jambrec Robert Sandulescu Cecilia Cristea 《Current Opinion in Electrochemistry》2017,6(1):183-192
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122.
Muñoz BK Godard C Marinetti A Ruiz A Benet-Buchholz J Claver C 《Dalton transactions (Cambridge, England : 2003)》2007,(47):5524-5530
Palladium complexes bearing phospholane 1 and phosphetane 2-4 ligands have been synthesised to be used as catalyst precursors in the asymmetric methoxycarbonylation of vinyl arenes. Single crystals of the complex [PdCl2(2)2] II were obtained from a toluene solution and analysed by X-ray crystallography. Using these complexes, excellent regioselectivity (up to 99%) to the branched esters was obtained. Phosphetane ligands provide higher enantioselectivity than the phospholane under the same reaction conditions and an important influence of the substrate was observed. Enantioselectivity up to 50% was obtained using 4-methoxystyrene. 相似文献
123.
Anilkumar G Bitterlich B Gelalcha FG Tse MK Beller M 《Chemical communications (Cambridge, England)》2007,(3):289-291
A new, environmentally benign and practical epoxidation method was developed using inexpensive and efficient Fe catalysts. FeCl3.6H2O in combination with commercially available pyridine-2,6-dicarboxylic acid and amines showed excellent reactivity and selectivity towards aromatic olefins and moderate reactivity towards 1,3-cyclooctadiene utilizing H2O2 as the terminal oxidant. 相似文献
124.
We report a study of the phase behavior of multiple-occupancy crystals through simulation. We argue that in order to reproduce the equilibrium behavior of such crystals, it is essential to treat the number of lattice sites as a constraining thermodynamic variable. The resulting free-energy calculations thus differ considerably from schemes used for single-occupancy lattices. Using our approach, we obtain the phase diagram and the bulk modulus for a generalized exponential model that forms cluster crystals at high densities. We compare the simulation results with existing theoretical predictions. We also identify two types of density fluctuations that can lead to two sound modes and evaluate the corresponding elastic constants. 相似文献
125.
Exceedingly Facile PhX Activation (X=Cl,Br, I) with Ruthenium(II): Arresting Kinetics,Autocatalysis, and Mechanisms
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Dr. Fedor M. Miloserdov Dr. David McKay Dr. Bianca K. Muñoz Dr. Hamidreza Samouei Prof. Stuart A. Macgregor Prof. Vladimir V. Grushin 《Angewandte Chemie (International ed. in English)》2015,54(29):8466-8470
[(Ph3P)3Ru(L)(H)2] (where L=H2 ( 1 ) in the presence of styrene, Ph3P ( 3 ), and N2 ( 4 )) cleave the Ph? X bond (X=Cl, Br, I) at RT to give [(Ph3P)3RuH(X)] ( 2 ) and PhH. A combined experimental and DFT study points to [(Ph3P)3Ru(H)2] as the reactive species generated upon spontaneous loss of L from 3 and 4 . The reaction of 3 with excess PhI displays striking kinetics which initially appears zeroth order in Ru. However mechanistic studies reveal that this is due to autocatalysis comprising two factors: 1) complex 2 , originating from the initial PhI activation with 3 , is roughly as reactive toward PhI as 3 itself; and 2) the Ph? I bond cleavage with the just‐produced 2 gives rise to [(Ph3P)2RuI2], which quickly comproportionates with the still‐present 3 to recover 2 . Both the initial and onward activation reactions involve PPh3 dissociation, PhI coordination to Ru through I, rearrangement to a η2‐PhI intermediate, and Ph? I oxidative addition. 相似文献
126.
Dr. Samir Das Dr. Arundhati Nag JingXin Liang Dr. David N. Bunck Dr. Aiko Umeda Blake Farrow Matthew B. Coppock Deborah A. Sarkes Amethist S. Finch Heather D. Agnew Suresh Pitram Bert Lai Mary Beth Yu Dr. A. Katrine Museth Dr. Kaycie M. Deyle Bianca Lepe Frances P. Rodriguez‐Rivera Amy McCarthy Belen Alvarez‐Villalonga Ann Chen John Heath Dimitra N. Stratis‐Cullum Prof. James R. Heath 《Angewandte Chemie (International ed. in English)》2015,54(45):13219-13224
We describe a general synthetic strategy for developing high‐affinity peptide binders against specific epitopes of challenging protein biomarkers. The epitope of interest is synthesized as a polypeptide, with a detection biotin tag and a strategically placed azide (or alkyne) presenting amino acid. This synthetic epitope (SynEp) is incubated with a library of complementary alkyne or azide presenting peptides. Library elements that bind the SynEp in the correct orientation undergo the Huisgen cycloaddition, and are covalently linked to the SynEp. Hit peptides are tested against the full‐length protein to identify the best binder. We describe development of epitope‐targeted linear or macrocycle peptide ligands against 12 different diagnostic or therapeutic analytes. The general epitope targeting capability for these low molecular weight synthetic ligands enables a range of therapeutic and diagnostic applications, similar to those of monoclonal antibodies. 相似文献
127.
Caradee Y. Wright David Jean du Preez Bice S. Martincigh Martin W. Allen Danielle A. Millar Bianca Wernecke Suzana Blesic 《Photochemistry and photobiology》2020,96(5):1148-1153
Urban environments can have high-risk spaces that can provide excess personal sun exposure, such as urban or street canyons, and the spaces between buildings, among others. In these urban spaces, sun exposure can be high or low depending on several factors. Polysulphone film (PSF) was used to assess possible daily solar ultraviolet radiation (UVR) exposure in urban canyons in Venice, Italy and, for the first time in Africa, in Johannesburg, South Africa. The photodegradation of PSF upon solar exposure was monitored at a wavelength of 330 nm by ultraviolet-visible spectrophotometry, and the resultant change was converted to standard erythemal dose (SED) units (1 SED = 100 J m−2). Mean daily ambient solar UVR exposure measured for Venice and Johannesburg ranged between 20–28 SED and 33–43 SED, respectively. Canyon-located PSF exposures were lower in Venice (1–9 SED) than those in Johannesburg (9–39 SED), depending mainly on the sky view factor and orientation to the sun. There was large variation in solar UVR exposure levels in different urban canyons. These preliminary results should be bolstered with additional studies for a better understanding of excess personal exposure risk in urban areas, especially in Africa. 相似文献
128.
129.
Margareth S. Alves Bianca M. R. Calsavara Jaime E. Mu?oz Rivera Mauricio Sep��lveda Octavio Vera Villagr��n 《Acta Appl Math》2011,113(1):75-100
Using Bourgain spaces and the generator of dilation P=3t ? t +x ? x , which almost commutes with the linear Korteweg-de Vries operator, we show that a solution of the initial value problem associated for the coupled system of equations of Korteweg-de Vries type which appears as a model to describe the strong interaction of weakly nonlinear long waves, has an analyticity in time and a smoothing effect up to real analyticity if the initial data only have a single point singularity at x=0. 相似文献
130.
Diederich P Hansen SK Oelmeier SA Stolzenberger B Hubbuch J 《Journal of chromatography. A》2011,1218(50):9010-9018
In process development and during commercial production of monoclonal antibodies (mAb) the monitoring of aggregate levels is obligatory. The standard assay for mAb aggregate quantification is based on size exclusion chromatography (SEC) performed on a HPLC system. Advantages hereof are high precision and simplicity, however, standard SEC methodology is very time consuming. With an average throughput of usually two samples per hour, it neither fits to high throughput process development (HTPD), nor is it applicable for purification process monitoring. We present a comparison of three different SEC columns for mAb-aggregate quantification addressing throughput, resolution, and reproducibility. A short column (150 mm) with sub-two micron particles was shown to generate high resolution (~1.5) and precision (coefficient of variation (cv)<1) with an assay time below 6 min. This column type was then used to combine interlaced sample injections with parallelization of two columns aiming for an absolute minimal assay time. By doing so, both lag times before and after the peaks of interest were successfully eliminated resulting in an assay time below 2 min. It was demonstrated that determined aggregate levels and precision of the throughput optimized SEC assay were equal to those of a single injection based assay. Hence, the presented methodology of parallel interlaced SEC (PI-SEC) represents a valuable tool addressing HTPD and process monitoring. 相似文献