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101.
This paper investigates whether inflation-targeting programs have altered the pattern of inflation and its variability for five developed countries and four emerging economies implementing inflation-targeting programs. A GARCH specification is used to model inflation variability, which accounts for public perception of the future levels of inflation variability—conditional variance. We could not find lower conditional inflation expectations except for Australia, Chile and Sweden under various specifications. Moreover, the conditional variance decreases only for Chile and the UK. Therefore, the empirical support for the lower inflation and its variability for the inflation targeting regimes is limited.  相似文献   
102.
A well-dispersed green Pd/SBA-15 catalyst with an average size of 13.7 nm and 492.6 m2/g BET surface area is prepared via supercritical fluid deposition method with a new bipyridyl precursor that enables reduction at mild conditions at 80 °C and 17.2 MPa. The catalytic performance of Pd/SBA-15 prepared using scCO2 with hydrogen reduction was assessed for Suzuki–Miyaura coupling reaction of bromobenzene and phenylboronic acid that was chosen as a model coupling reaction. The catalyst was tested in six different solutions and in three organic and inorganic bases during reactions. In general, the effect of bases is investigated when solvents are held constant and K2CO3 appears to have the best results in the activity studies used. For each of the 3 bases used, the highest catalytic activity was reached as the result of the solvent system being ethanol/water (1:1). The highest catalytic conversion was obtained in the ethanol-K2CO3 solvent-base pair. The catalyst synthesized in this study exhibited high activities and TON value was found as 160.8 at room temperature.  相似文献   
103.
Research on Chemical Intermediates - We synthesized and characterized a series of four closely related thiourea derivatives (1–4) obtained by reaction of 4-R-benzoyl chloride (R: H, Cl, CH3,...  相似文献   
104.
Transparent conductive ZnO film was deposited on glass substrate by pulsed filtered cathodic vacuum arc deposition (PFCVAD). Optical parameters such as absorption coefficient α, the refractive index n, energy band gap Eg and dielectric constants have been determined using different methods. Kramers-Kronig and dispersion relations were employed to determine the complex refractive index and dielectric constants using reflection data in the ultraviolet-visible-near infrared regions. The spectra of the dielectric coefficient were used to calculate the energy band gap and the value was 3.24 eV. The experimental energy band gap was found to be 3.22 eV for 357 nm thick ZnO thin film. The envelope method was also used to calculate the refractive index and the data were consistent with K-K relation results. The structure of the film was analyzed with an x-ray diffractometer and the film was polycrystalline in nature with preferred (002) orientation.  相似文献   
105.
Polyelectrolyte-colloid coacervation could be viewed as a sub-category of complex coacervation, but is unique in (1) retaining the structure and properties of the colloid, and (2) reducing the heterogeneity and configurational complexity of polyelectrolyte-polyelectrolyte (PE-PE) systems. Interest in protein-polyelectrolyte coacervates arises from preservation of biofunctionality; in addition, the geometric and charge isotropy of micelles allows for better comparison with theory, taking into account the central role of colloid charge density. In the context of these two systems, we describe critical conditions for complex formation and for coacervation with regard to colloid and polyelectrolyte charge densities, ionic strength, PE molecular weight (MW), and stoichiometry; and effects of temperature and shear, which are unique to the PE-micelle systems. The coacervation process is discussed in terms of theoretical treatments and models, as supported by experimental findings. We point out how soluble aggregates, subject to various equilibria and disproportionation effects, can self-assemble leading to heterogeneity in macroscopically homogeneous coacervates, on multiple length scales.  相似文献   
106.
Hydrophobic- and/or hydrophilic-polymer-grafted PDVB microspheres are synthesized by the combination of hydrobromination and click-chemistry processes. The modified-PDVB microspheres and the intermediates at various stages of synthesis are characterized using GPC, 1H NMR and FTIR spectroscopy and TGA analysis. Use of the microspheres as a support matrix for reversible protein immobilization via adsorption is investigated. The system parameters such as the adsorption conditions (i.e., enzyme concentration, medium pH) and desorption are studied and evaluated with regards to the biocatalytic activity and adsorption capacity.  相似文献   
107.
108.
The previously developed methodologies for fabricating flat, polished nanoelectrodes were extended to produce silver electrodes with the radii from 50 nm to micrometers. The prepared electrodes were characterized by steady-state voltammetry, scanning electrochemical microscopy (SECM), and atomic force microscopy. The protocol was developed for controlled chemical etching of silver in ammonia solutions to produce recessed nanoelectrodes. Voltammograms and SECM approach curves were obtained to evaluate the recess depth and other geometric parameters of the etched electrodes.  相似文献   
109.
While transfusion safety, particularly with respect to transfusion-transmitted infectious diseases, has improved dramatically over the past several decades, progress in other clinical processes of blood product transfusion continue with highly variable practices and human errors that contribute to adverse outcomes. In this paper, we study the adverse outcome risk in red blood cell (RBC) transfusion in the United States using Probabilistic Risk Assessment (PRA). PRA allows us to map, in a comprehensive manner, the various types of events that may contribute to an adverse outcome, including socio-technical factors such as the risk coming from human error; and allows us to formalize the logical relationships among those events and the adverse outcome risk. We utilize the PRA model to assess the risk to the patient from RBC transfusion in the United States, to identify the major risk points in the transfusion process, and to evaluate the costs and benefits of several risk reduction strategies. Our data come from published studies in the medical literature. We find that the risk of a potentially severe outcome (e.g., mortality, major injury or other serious long-term consequences, a life threatening incident) from RBC transfusion lies in the interval [10.4327,511.2] per 100,000 units of RBC transfused, with a point estimate of 25.4527. The leading causes of severe outcomes include circulatory overload and bacterial infection. Acute hemolytic reactions, which are mainly caused by erroneous administration of the blood, also contribute significantly to severe outcomes of transfusion. Interestingly, our analysis indicates that an intervention that is targeted at reducing the risk of the erroneous administration of blood (through training programs or technology investments) has a higher potential impact in reducing the severe outcome risk from RBC transfusion than additional screening to further reduce the risk of transfusion-transmitted viral infections, of HIV 1-2, hepatitis B, and hepatitis C, which the lay public fears most. Furthermore, such an error reduction program will be more cost-effective than the additional screening of donated blood. Our study provides guidelines for public policy to improve the safety of RBC transfusion in the United States.  相似文献   
110.
Conventional cancer treatments such as chemotherapy, radiotherapy, or combination of these two result in side effects, which lower the quality of life of the patients. To overcome problems with these methods, altering the drug properties by conjugating them to carrier polymers has emerged. Such polymeric carriers also hold the potential to make tumor cells more sensitive to radiation therapy. Herein, poly(p‐phenylene) (PPP) polymer with poly(ethylene glycol) (PEG) chains and primary amino groups (PPP‐NH2g‐PEG) is synthesized and conjugated with anticancer drug Doxorubicin (DOX). pH dependent drug release experiments are performed at pH 5.3 and pH 7.4, respectively. Cell viability studies on human cervix adenocarcinoma cells show that lower doses of DOX inhibit cell proliferation when conjugated with nontoxic doses of PPP‐NH2g‐PEG polymer. Additionally, PPP‐NH2g‐PEG/Cys/DOX bioconjugate significantly increases radiosensitive properties of DOX. It is possible to use lower doses of DOX when conjugated to PPP‐NH2g‐PEG in combination with radiotherapy.

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