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71.
Gignac LM Mittal S Bangsaruntip S Cohen GM Sleight JW 《Microscopy and microanalysis》2011,17(6):889-895
The ability to prepare multiple cross-section transmission electron microscope (XTEM) samples from one XTEM sample of specific sub-10 nm features was demonstrated. Sub-10 nm diameter Si nanowire (NW) devices were initially cross-sectioned using a dual-beam focused ion beam system in a direction running parallel to the device channel. From this XTEM sample, both low- and high-resolution transmission electron microscope (TEM) images were obtained from six separate, specific site Si NW devices. The XTEM sample was then re-sectioned in four separate locations in a direction perpendicular to the device channel: 90° from the original XTEM sample direction. Three of the four XTEM samples were successfully sectioned in the gate region of the device. From these three samples, low- and high-resolution TEM images of the Si NW were taken and measurements of the NW diameters were obtained. This technique demonstrated the ability to obtain high-resolution TEM images in directions 90° from one another of multiple, specific sub-10 nm features that were spaced 1.1 μm apart. 相似文献
72.
Liu L Yang J Li J Dong J Sišak D Luzzatto M McCusker LB 《Angewandte Chemie (International ed. in English)》2011,50(35):8139-8142
Less is more: an open-framework zirconium phosphate with unusual 7-ring channels was synthesized ionothermally from a deep-eutectic solvent. This small-pore material displays a CO(2)/CH(4) adsorption ratio (17.3 at 1 bar) that is significantly higher than that of typical 8-ring materials, making it highly attractive for CO(2)/CH(4) separations. 相似文献
73.
Graham K Ferguson A Douglas FJ Thomas LH Murrie M 《Dalton transactions (Cambridge, England : 2003)》2011,40(13):3125-3127
We describe an enneanuclear Fe(III) complex with an unusual boat-shaped core topology and an S=11/2 ground state, assembled using the ligands tricine {N-(2-hydroxy-1,1-bis(hydroxymethyl)ethyl)glycine, H(4)L} and 2-phenoxybenzoate. 相似文献
74.
Chong JY Mulet X Waddington LJ Boyd BJ Drummond CJ 《Langmuir : the ACS journal of surfaces and colloids》2012,28(25):9223-9232
High-throughput methodologies have been employed to establish structure-property relationships and assess the effectiveness of nonionic steric stabilizers for inverse bicontinuous cubic lyotropic liquid crystalline nanoparticulate dispersions of monoolein and phytantriol. The ability of the stabilizers to disperse the lipids was compared with that of the commonly employed triblock poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) copolymer Pluronic F127, which was used as a positive control. The poly(ethylene oxide) stearate class of stabilizers (commercially known as Myrj) were discovered to be effective as steric stabilizers for cubosomes, while retaining the internal nanostructure of the "parent" bulk phase. In particular, Myrj 59, with an average of 100 poly(ethylene oxide) units, was more effective than F127 at dispersing phytantriol, forming stable phytantriol cubosome dispersions at a concentration of 0.1 wt %, 5-fold lower than that achievable with Pluronic F127. The discovery of this new effective class of stabilizers for cubosomes, specifically enabled by high-throughput approaches, broadens the versatility of components from which to construct these interesting potential drug delivery and medical imaging nanoparticles. 相似文献
75.
Nisa V. Salim Tracey L. Hanley Lynne Waddington Patrick G. Hartley Qipeng Guo 《Macromolecular rapid communications》2012,33(5):401-406
This work reports for the first time a simple and effective approach to trigger a spheres‐to‐ vesicles morphological transition from amphiphilic block copolymer/polyelectrolyte complexes in aqueous solution. Vesicles and large compound vesicles (LCVs) were prepared via complexation of polystyrene‐block‐poly(ethylene oxide) (PS‐b‐PEO) with poly(acrylic acid) (PAA) in water and directly visualized using cryo‐TEM. The complexation and morphological transitions were driven by the hydrogen bonding between the complementary binding sites on the PAA and PEO blocks of the block copolymer. The findings in this work suggest that complexation between amphiphilic block copolymer and polyelectrolyte is a viable approach to vesicles and LCVs in aqueous media. 相似文献
76.
77.
Archive for Rational Mechanics and Analysis - 相似文献
78.
Marc J. Kaufman Tak-Ming Chiu Jack H. Mendelson Bryan T. Woods Nancy K. Mello Scott E. Lukas Peter A. Fivel Lynne G. Wighton 《Magnetic resonance imaging》1994,12(8):1245-1253
Brain alcohol was measured in rhesus monkeys (Macaca mulatta) by proton magnetic resonance spectroscopy (MRS) following acute nasogastric alcohol administration (0.8 g/kg). Monkeys were anesthetized with ketamine and xylazine. A 1.5 T whole body imager and a 3-inch surface coil were used to acquire TE 30 and 270 ms spectra from a 7.5 cc voxel localized with a stimulated echo (STEAM) sequence. Venous blood samples were collected during spectral acquisitions for gas chromatographic determination of temporally concordant blood alcohol levels (BALs). Acute alcohol administration did not alter the resonance areas of N-acetylaspartate/N-acetyl containing compounds (NAA), choline containing compounds, or total creatine. The NAA resonance was used as an internal standard to calculate approximate brain alcohol concentrations, which averaged 27 ± 3% and 27 ± 8% of temporally concordant BALs (T2-corrected TE 30 and TE 270 ms spectra, respectively). In addition to reconfirming results from prior studies finding incomplete detection of brain alcohol with MRS, these results demonstrate the feasibility of measuring brain alcohol in anesthetized nonhuman primates to examine relationships between alcohol exposure history and MRS-visibility of brain alcohol. 相似文献
79.
Parametric ranked set sampling 总被引:1,自引:0,他引:1
Lynne Stokes 《Annals of the Institute of Statistical Mathematics》1995,47(3):465-482
Ranked set sampling was introduced by McIntyre (1952,Australian Journal of Agricultural Research,3, 385–390) as a cost-effective method of selecting data if observations are much more cheaply ranked than measured. He proposed its use for estimating the population mean when the distribution of the data was unknown. In this paper, we examine the advantage, if any, that this method of sampling has if the distribution is known, for a specific family of distributions. Specifically, we consider estimation of and for the family of random variables with cdf's of the formF(x–/). We find that the ranked set sample does provide more information about both and than a random sample of the same number of observations. We examine both maximum likelihood and best linear unbiased estimation of and , as well as methods for modifying the ranked set sampling procedure to provide even better estimation.This paper has been prepared with partial support from the United States Environmental Protection Agency under Cooperative Agreement Number CR821801-01-0. The contents have not been subjected to Agency review and therefore do not necessarily reflect the views or policies of the Agency and no official endorsement should be inferred. 相似文献
80.
Autoantibodies to thyroglobulin in health and disease 总被引:2,自引:0,他引:2
Thyroglobulin (Tg)—a heavily glycosylated, iodinated protein—isa major autoantigen in autoimmune thyroiditis. Tg also induces
thyroiditis by immunization of experimental animals. Humans with chronic lymphocytic thyroiditis characteristically produce
autoantibodies to thyroglobu lin, but similar autoantibodies are also found in some clinically normal, euthyroid individuals.
A comparison of the fine specificity of autoantibodies in humans and in experimentally immunized mice was carried out, based
on their ability to inhibit a panel of monoclonal antibodies (MAbs). Patients with autoimmune thyroid disease, as well as
normal individuals, produced autoantibodies mainly to the conserved, cross-reactive determinants of thyroglobulin. Patients
developed additional autoantibodies to species-restricted epitopes. The determinants recognized by patients with Graves' disease
differed in some respects from epitopes recognized by thyroiditis patients or patients with differentiated thyroid carcinoma.
Similarly, mice that are genetically susceptible to thyroiditis produced autoantibodies that reacted with the mouse-specific
antigenic determinants. Using an autoantibody that reacts with one of the epitopes associated with thyroiditis, a reactive
15-k Da fragment of human Tg—localized at the carboxy end of the molecule—was isolated and sequenced. Iodine plays an important
role in the precise specificity of the disease-associated epitope, since T cells from patients with thyroiditis react with
iodinated but not noniodinated human thyroglobulin. Addition of iodine to Tg generates new or cryptic epitopes. Use of a selected
MAb as a surrogate for the T-cell receptor suggests that a specific iodine-containing epitope is sometimes involved in recognition.
Finally, thyroglobulin-reactive autoantibodies exhibit proteolytic activity on thyroglobulin. 相似文献