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71.
H. Fan A. Wright J. Gabaldon A. Rodriguez C.J. Brinker Y.‐B. Jiang 《Advanced functional materials》2006,16(7)
The synthesis of three‐dimensionally ordered, transparent gold‐nanocrystal (NC)/silica superlattice thin films using the self‐assembly (by spin‐coating) of water‐soluble gold nanocrystal micelles and soluble silica is reported by Fan and co‐workers on p. 891. The robust, 3D NC/silica superlattice films are of interest for the development of collective optical and electronic phenomena, and, importantly, for the integration of NC arrays into device architectures. Nanocrystals and their ordered arrays hold many important applications in fields such as catalysis, surface‐enhanced Raman spectroscopy based sensors, memory storage, and electronic and optical nanodevices. Herein, a simple and general method to synthesize ordered, three‐dimensional, transparent gold nanocrystal/silica superlattice thin films by self‐assembly of gold nanocrystal micelles with silica or organosilsesquioxane by spin‐coating is reported. The self‐assembly process is conducted under acidic sol–gel conditions (ca. pH 2), ensuring spin‐solution homogeneity and stability and facilitating the formation of ordered and transparent gold nanocrystal/silica films. The monodisperse nanocrystals are organized within inorganic host matrices as a face‐centered cubic mesostructure, and characterized by transmission electron spectroscopy and X‐ray diffraction. 相似文献
72.
Bellovin Steven M. Benzel Terry V. Blakley Bob Denning Dorothy E. Diffie Whitfield Epstein Jeremy Verissimo Paulo 《Security & Privacy, IEEE》2008,6(1):16-23
A virtual roundtable (featuring panelists Steven Bellovin, Terry Benzel, Bob Blakely, Dorothy Denning, Whitfield Diffie, Jeremy Epstein, and Paulo Verissimo) discussing the next 15 years in computer security. 相似文献
73.
The paper describes a reduced forward operator for solving electromagnetic scattering problems using a volume integral equation in conjunction with a conjugate gradient fast Fourier transform scheme. The reduction is obtained by decoupling of the interaction between the locations in the spatial computational domain at which there is non-zero contrast and those positions at which there is zero contrast. The decoupling is achieved by multiplication of the kernel by a diagonal matrix whose entries reflect the presence or absence of contrast at the associated point. Analysis supported by numerical experiments shows that the conjugate gradient algorithm applied to the reduced system converges more rapidly than when it is applied to the original system 相似文献
74.
75.
Kaslow Nadine J.; Rubin Nancy J.; Forrest Linda; Elman Nancy S.; Van Horne Barbara A.; Jacobs Sue C.; Huprich Steven K.; Benton Sherry A.; Pantesco Victor F.; Dollinger Stephen J.; Grus Catherine L.; Behnke Stephen H.; Miller David S. Shen; Shealy Craig N.; Mintz Laurie B.; Schwartz-Mette Rebecca; Van Sickle Kristi; Thorn Beverly E. 《Canadian Metallurgical Quarterly》2007,38(5):479
Working collaboratively, psychologist educators and trainers at the doctoral, internship, and postdoctoral levels; credentialers; practitioners; and students offer 8 proposals for psychologists to consider in recognizing, assessing, and intervening with problems of professional competence in students and practicing professionals. In the proposals, the authors address the following topics: definitions and categories; preparing the system; self-assessment; remediation; diversity; communication across various levels of the system; confidentiality; and ethical, regulatory, and legal underpinnings. They also propose future directions for the assessment of problems in professional competence in both students and practicing psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
Capital cost correlations are given for oil-water separators, equalization basins, primary clarifiers, clarifiers and clarifier mechanisms, reverse osmosis unit, ultrafiltration units, gravity filters and miroscreens. Data are included for raw sewage, intermediate and recirculation pumping stations and for preliminary treatment (or bar screens, grit removal, overflow and bypass chamber and Parshall flume), for grit removal, comminution and gas stripping. The correlations are accurate to ± 30%, expressed in Canadian dollars and adjusted to a Marshall and Swift value of 1000. Details as to what components are included in the cost are given. Data are given for the labour and material costs to create a working process module. For inflation indices, a critique of the Engineering News Record, EPA small city, Marshall and Swift, Chemical Engineering and Southam inflation indices suggested that the Marshall and Swift index is most appropriate for the construction and process equipment studied here. Concerning the currency exchange, for the equipment and processes in this study, equipment costs the same whether expressed directly in US or Canadian dollars. To put the current data into perspective, several hundred sources of cost data were analyzed. The major correlations are compared, on a consistent basis, with current data. 相似文献
77.
Julian P. Wright Alan G. Jack 《International journal for numerical methods in engineering》1994,37(11):1841-1861
Presented in this paper are the theoretical aspects of node addition to a non-convex, multiboundary mesh of tetrahedral elements as used in finite element modelling. The method used is derived from Watson1 and Shenton and Cendes2 and is extended to deal with node addition on inter-material boundaries. Several situations are identified that result in an illegal insertion polyhedron (IP), these could be caused by the ‘constrained’ nature of the mesh, adjacent objects with different material properties, or degenerate node configurations. A new Delaunay algorithm is described that checks for illegal cases of the IP and then corrects them, this checking relies on the consistent ordering of the element nodes. It is shown that a particular type of illegal IP can easily be identified and corrected using this technique. The Delaunay algorithm is then applied to automatic mesh generation, and modification to the basic Delaunay algorithm is described so that previously meshed edges and faces of the current object being meshed are not deleted during the addition of subsequent nodes. This ‘protection’ method only becomes viable by recognizing the node ordering sense of the IP faces. 相似文献
78.
This article reviews the impact of infection with human immunodeficiency virus (HIV) on HPV infections and HPV-associated lesions of the female anogenital tract. Studies investigating HPV infections in HIV-seropositive women are presented as well as the possibility that HIV can influence HPV expression directly through molecular interactions between viral genes and indirectly through immunosuppression. Studies linking HIV infection to invasive cervical cancer and cervical intraepithelial neoplasia are reviewed; recommended protocols for cervical cancer screening in HIV-seropositive women for cervical disease also are presented. 相似文献
79.
Responsiveness of self-reported and objective measures of disease severity in carpal tunnel syndrome
JN Katz RH Gelberman EA Wright RA Lew MH Liang 《Canadian Metallurgical Quarterly》1994,32(11):1127-1133
Responsiveness, the ability to detect meaningful clinical change, is a critical attribute of instruments used to evaluate outcomes of treatments. The authors hypothesized that self-administered symptom severity and functional status questionnaires are more responsive to clinical improvement after carpal tunnel release than traditional physical examination measures of strength and sensibility. Data were obtained from a randomized clinical trial of endoscopic versus open carpal tunnel release conducted in four university medical centers. Patients were evaluated before surgery and 3 months after surgery. Seventy-four patients indicating that they were more than 80% satisfied with the results of surgery were assumed to have clinically meaningful improvement and were the focus of the analysis. Evaluations included questionnaires assessing symptom severity, functional status, and activities of daily living as well as measurement of grip, pinch, and abductor pollicus brevis strength, and 2-point discrimination and Semmes-Weinstein pressure sensibility. Responsiveness was calculated with the standardized response mean (mean change/standard deviation of change) as well as the effect size (mean change/standard deviation of baseline values). The symptom severity scale was four times as responsive, and the functional status and activities of daily living scales were twice as responsive, as the measures of strength and sensibility. Self-administered symptom severity and functional status scales are much more responsive to clinical improvement than measures of neuromuscular impairment and should severe as primary outcomes in clinical studies of therapy for carpal tunnel syndrome. 相似文献
80.
Lu Shen Beng Jit Tan William S. Willis Francis S. Galasso Steven L. Suib 《Journal of the American Ceramic Society》1994,77(4):1011-1016
Amorphous boron nitride thin coatings (∼0.2 μm) have been formed on Nicalon and C-Nicaion (pre-carbon-coated Nicalon) yarns via dip coating in boric acid solution followed by heating and nitriding in NH3 gas at 1000°C. X-ray photoelectron spectroscopy (XPS) and Auger electron spec-troscopy (AES) studies have shown the formation of boron nitride. The coating was boron rich and contains oxygen. The N/B and O/B ratios range from 0.6 to 0.8 and from 0.1 to 0.25, respectively. Tensile strength measurements revealed that the BN-coated C-Nicalon yarn maintained ∼85% of its original strength while BN-coated Nicalon lost ∼85% of its original strength. Auger depth profiles showed that there was a consumption of carbon during the heating and nitridation process for both BN-coated Nicalon and C-Nicalon fibers. However, the depletion of carbon in BN-coated Nicalon fibers was much more severe than that in BN-coated C-Nicalon fibers. 相似文献