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91.
Jovita Mendoza-Barrón Araceli Jacobo-Azuara Roberto Leyva-Ramos Ma. Selene Berber-Mendoza Rosa Ma. Guerrero-Coronado Laura Fuentes-Rubio J. Merced Martínez-Rosales 《Adsorption》2011,17(3):489-496
In this study a surfactant-modified zeolite (SMZ) was prepared by adsorbing the cationic surfactant hexadecyltrimethylammonium
(HDTMA) bromide on a clinoptilolite. The adsorption of the surfactant modified the surface properties of the clinoptilolite
and enhanced the anionic capacity of the SMZ. The adsorption equilibrium data of As(V) from the water solution on the SMZ
were obtained in a batch adsorber, and the Langmuir isotherm matched the data reasonably well. The As(V) adsorption capacity
of the SMZ was 12.5 times greater than that of the clinoptilolite. The adsorption of As(V) on SMZ was mainly due to the interactions
between the anionic sites of the SMZ and the As(V) anions in water solution. The adsorption capacity of the SMZ was dependent
on the solution pH. The adsorption capacity was increased and decreased by augmenting the pH from 5 to 7 and from 7 to 12,
respectively. This unusual behavior was due to the fact that the affinity of the As(V) for the SMZ was dependent on the As(V)
species that were present in solution. The adsorption capacity of the SMZ was slightly favored by decreasing the temperature
from 25 to 15 °C. The heat of adsorption was estimated to be ΔH
ads=−46.82 KJ/mol, indicating that the adsorption was exothermic and the As(V) was chemisorbed on the SMZ. 相似文献
92.
Sewell LJ Chaplin AB Weller AS 《Dalton transactions (Cambridge, England : 2003)》2011,40(29):7499-7501
The catalytic hydroboration of tert-butylethene using H(3)B·NMe(3) gives RH(2)B·NMe(3). With H(3)B·NMe(2)H tandem hydroboration under mild conditions/dehydrocoupling occurs that produces R(2)B=NMe(2) (R = H, CH(2)CH(2)(t)Bu). 相似文献
93.
Marla D. Swain George P. Anderson Dan Zabetakis Rachael D. Bernstein Jinny L. Liu Laura J. Sherwood Andrew Hayhurst Ellen R. Goldman 《Analytical and bioanalytical chemistry》2010,398(1):339-348
Single-domain antibodies (sdAb) specific for botulinum neurotoxin serotype A (BoNT A) were selected from an immune llama phage
display library derived from a llama that was immunized with BoNT A toxoid. The constructed phage library was panned using
two methods: panning on plates coated with BoNT A toxoid (BoNT A Td) and BoNT A complex toxoid (BoNT Ac Td) and panning on
microspheres coupled to BoNT A Td and BoNT A toxin (BoNT A Tx). Both panning methods selected for binders that had identical
sequences, suggesting that panning on toxoided material may be as effective as panning on bead-immobilized toxin for isolating
specific binders. All of the isolated binders tested were observed to recognize bead-immobilized BoNT A Tx in direct binding
assays, and showed very little cross-reactivity towards other BoNT serotypes and unrelated protein. Sandwich assays that incorporated
selected sdAb as capture and tracer elements demonstrated that all of the sdAb were able to recognize soluble (“live”) BoNT
A Tx and BoNT Ac Tx with virtually no cross-reactivity with other BoNT serotypes. The isolated sdAb did not exhibit the high
degree of thermal stability often associated with these reagents; after the first heating cycle most of the binding activity
was lost, but the portion of the protein that did refold and recover antigen-binding activity showed only minimal loss on
subsequent heating and cooling cycles. The binding kinetics of selected binders, assessed by both an equilibrium fluid array
assay as well as surface plasmon resonance (SPR) using toxoided material, gave dissociation constants (K
D ) in the range 2.2 × 10−11 to 1.6 × 10−10 M. These high-affinity binders may prove beneficial to the development of recombinant reagents for the rapid detection of
BoNT A, particularly in field screening and monitoring applications. 相似文献
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98.
This paper proposes to obtain homogeneous and stable blends of oligo(9,9-dioctylfluorene)-co-phenylene (OF), a conjugated oligomer with strong tendency of formation of excimers in the solid state, and nitrile rubber (NBR). This rubber protection reduces the formation of polymer excimers in the films. The fluorene oligomer was synthesized via Suzuki reaction and incorporated in the nitrile rubber. The films were formed by spin coating and casting techniques on the proportions of 1, 5, 10, 20 and 50 % (w/w) of OF in the nitrile rubber (NBR). The structural, optical and thermal properties of the films were evaluated with infrared, UV–Vis, fluorescence and thermogravimetry, respectively. The nitrile rubber proved to be essential for the preparation of homogeneous and stable films, since it was not possible to obtain films with only fluorene using the above-mentioned techniques. Furthermore, luminescent properties of OF are unchanged and the excimers formation in the solid state decrease suggesting the efficiency of nitrile rubber as the matrix for making films. 相似文献
99.
A method for analyzing the influence of noise on newborns is proposed. The method consists of defining three different types of time interval (quiet, noisy and nursing) and, for each period, environmental noise levels, heart rate, mean arterial pressure and oxygen saturation is continuously measured. The statistical analysis of the influence of the equivalent noise level, rather than instantaneous noise level, on the behavior of the physiological variables is carried out. Great influence of noise is found by using this method, which is also easily translatable to other intensive care units as actual noise conditions are used in the investigation. Moreover, episodes of Bradycardia, Hypoxia and Hypertension are easily related to simultaneous direct nursing activity or a short but high enough noise event, suggesting that both sustained noisy environment and isolated peak noises lead to the alteration of the physiological variables. 相似文献
100.
An unexpected reaction took place when 5-phenylthiazolidine-2,4-diones were treated in basic media to produce phenyl-α-ketoamides in good yields. The 5-phenylthiazolidine-2,4-diones used as reactants were achieved through a rearrangement, which took place in the corresponding N-acyloxazolidinethiones. 相似文献