The completely c3-selective arylation of thiophenes and benzo[b]thiophenes was achieved by using Pd/c as a heterogeneous catalyst without ligands or additives under mild reaction conditions. The practicability of this...
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The completely c3-selective arylation of thiophenes and benzo[b]thiophenes was achieved by using Pd/c as a heterogeneous catalyst without ligands or additives under mild reaction conditions. The practicability of this transformation is demonstrated by notable functional group tolerance and the insensitivity of the reaction to H2O and air. This method is also applicable to nitrogen- and oxygen-containing heterocycles, yielding the corresponding c2-arylated products. Three-phase tests along with Hg-poisoning and hot-filtration tests suggest that the catalytically active species is heterogeneous in nature.
This paper applies new wavelet-based analysis procedures to low Earth-orbiting satellite measurements of equatorial ionospheric structure. The analysis was applied to high-resolution data from 285 communications/Navig...
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This paper applies new wavelet-based analysis procedures to low Earth-orbiting satellite measurements of equatorial ionospheric structure. The analysis was applied to high-resolution data from 285 communications/Navigation Outage Forecasting System (c/NOFS) satellite orbits sampling the postsunset period at geomagnetic equatorial latitudes. The data were acquired during a period of progressively intensifying equatorial structure. The sampled altitude range varied from 400 to 800 km. The varying scan velocity remained within 20 degrees of the cross-field direction. Time-to-space interpolation generated uniform samples at approximately 8 m. A maximum segmentation length that supports stochastic structure characterization was identified. A two-component inverse power law model was fit to scale spectra derived from each segment together with a goodness-of-fit measure. Inverse power law parameters derived from the scale spectra were used to classify the scale spectra by type. The largest category was characterized by a single inverse power law with a mean spectral index somewhat larger than 2. No systematic departure from the inverse power law was observed to scales greater than 100 km. A small subset of the most highly disturbed passes at the lowest sampled altitudes could be categorized by two-component power law spectra with a range of break scales from less than 100 m to several kilometers. The results are discussed within the context of other analyses of in situ data and spectral characteristics used for scintillation analyses.
cobalt and zirconium doped ferrite pellets of composition are synthesized successfully using the sol-gel method with two different precursors: citric Acid and Tartaric Acid. Dielectricconstant and dielectric loss tan...
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cobalt and zirconium doped ferrite pellets of composition are synthesized successfully using the sol-gel method with two different precursors: citric Acid and Tartaric Acid. Dielectricconstant and dielectric loss tangent measurements are performed in the frequency range 20Hz - 120MHz over Impedance analyzer. A.c. conductivity is calculated from Debye's equation of complex permittivity. Dielectricconstant and loss tangent are found to be varying in accordance to Maxwell-Wagner theory of interfacial polarization. A.c. conductivity is found to increase with increase in frequency as well as doping amount. Dielectric analysis of two series concludes that ferrites prepared using tartaric acid have higher values of dielectric properties at lower frequencies in comparison to those prepared with citric acid, while at higher frequencies, the effect of precursors seems to be insignificant. The enhancement of dielectricconstant and dielectric loss with increase in dopant concentration suggests that these samples are promising materials for applications in microwave devices.
We report the recent isolation of cryptococcus laurentii from the feces of a patient with Hodgkin's lymphoma who underwent autologous hematopoietic stem cell transplant (HScT). The organism was identified using mi...
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We report the recent isolation of cryptococcus laurentii from the feces of a patient with Hodgkin's lymphoma who underwent autologous hematopoietic stem cell transplant (HScT). The organism was identified using microscopic morphology, cultural characteristics, and biochemical tests including sugar assimilation. Minimum inhibitory concentration of various antifungals was determined by microbroth dilution method. The recovery of pure culture of *** from stool culture, and the patient's response to treatment with voriconazole support its potential etiological role. To the best of our knowledge, we report the first case of diarrhea caused by *** in an HScT recipient.
Local control of dopant profiles and ordered doping in high T c superconductors have the potential to greatly increase the transition temperature, T c . We report on experiments where we used focused electron beams to...
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Local control of dopant profiles and ordered doping in high T c superconductors have the potential to greatly increase the transition temperature, T c . We report on experiments where we used focused electron beams to locally modulate the oxygen dopant concentration in commercial YBcO films (100 nm on LaAlO 3 ). Patterned exposure of YBcO samples to 10 keV electrons and fluences in the 10 20 e - /cm 2 range led to increases of T c of ∼0.4 K, comparable to earlier reports from broad beam exposures in a similar fluence regime. We discuss our results in relation to concepts of local oxygen depletion and chain ordering induced by ionizing radiation and outline possible processing paths to implement a form of modulation doping in YBcO by patterning with intense, short excitation pulses (e. g. of MeV protons).
[Objective] The paper was to explore the relationship between the occurrence of canine rheumatism and blood-associated agent by detecting blood routine indexes and changes in content of anti streptolysin O( ASO),c-rea...
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[Objective] The paper was to explore the relationship between the occurrence of canine rheumatism and blood-associated agent by detecting blood routine indexes and changes in content of anti streptolysin O( ASO),c-reactive protein( cRP) and antinuclear antibody( ANA). [Method]Totally 13 cases of dogs which had been diagnosed with rheumatism by the reference standard of clinical examinations and laboratory diagnosis were selected for treatment,and their venous blood was collected on the day of diagnosis and at 1,3,5 d after treatment,respectively. Another 13 healthy dogs were selected randomly to collect venous blood as well. The white blood cells( WBc) count,neutrophilic granulocyte( Gran#),lymphocyte count( Lymph#) and blood routine index were determined using automatic animal blood cell analyzer. The content of ASO,cRP and ANA were determined using enzyme-linked immunosorbent assay( ELISA). [Result]Blood routine examination showed that there were significant differences in WBc between untreated rheumatismal dogs and healthy dogs( P < 0. 05),but no significant difference was observed on the day of diagnosis and duration of therepay( P > 0. 05). Detection results of blood-associated agent in rheumatismal dogs showed that there were extremely significant differences in ASO and ANA content between the day of diagnosis and duration of therapy( P < 0. 01); there were significant differences in Lymph# and Gran# content of cRP between the day of diagnosis and duration of therapy( P < 0. 05). The ASO,ANA and cRP content in the serum of untreated rheumatismal dogs were higher than those in healthy dogs,and the content of various indicators decreased significantly after treatment,but were still higher than that in healthy dogs. [conclusion]The incidence of canine rheumatism is positively correlated with WBccount,ASO content,cRP content and ANA content. The variation of cRP content is the most sensitive indicator of the disease.
In this article, four different numerical models for the investigation of phase change processes within latent heat storage are described and compared concerning accuracy, convergence behavior and computational effici...
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In this article, four different numerical models for the investigation of phase change processes within latent heat storage are described and compared concerning accuracy, convergence behavior and computational efficiency. The models are based on different types of discretization, make use of different ways to model phase change and are implemented with c, MATLAB or ANSYS cFX. After a brief introduction into each investigated numerical model, the experimental reference setup is described. It consists of a flat plate latent heat storage with the eutectic mixture NaNO3 (46 wt%)-KNO3 (54 wt%) with a measured melting temperature of 219.5 degrees c as storage material. Based on the corresponding simulation model developed in this paper, the comparison of the numerical models is achieved. This methodology allows the investigation of the numerical performance of different software tools in the context of high temperature latent heat storage that was not achieved thus far. All four numerical models show good agreement to experimental results but differ significantly in speed and convergence behavior. (c) 2015 Elsevier Ltd. All rights reserved.
New technologies are changing the old and the new alike Guangzhou,a millennia-old commercial city and once the first port in china to open to the outside world and the testing ground of china’s market economy in the ...
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New technologies are changing the old and the new alike Guangzhou,a millennia-old commercial city and once the first port in china to open to the outside world and the testing ground of china’s market economy in the 1970s,hosted hundreds of business elites from over30 countries and regions under one roof in early *** the theme Openness and Innovation:Shaping the Global Economy,the Fortune Global Forum 2017 lasted from December 6 to 8,with inclusive cooperation,sustainable development and innovation
This study reports new facile approach for gram-scale synthesis of graphene-like nanosheets fine powder, using glucose as precursor. Reduced graphene oxide (RGO) has been prepared in gram-scale via hydrothermal treatm...
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This study reports new facile approach for gram-scale synthesis of graphene-like nanosheets fine powder, using glucose as precursor. Reduced graphene oxide (RGO) has been prepared in gram-scale via hydrothermal treatment of glucose. Upon increasing the vapor/liquid ratio for aqueous glucose solution within the autoclave system to 3/2, RGO-rich graphitic powder, containing small graphene oxide and amorphous carbon contents and having spherical morphology, is obtained. Then, introducing ammonia into the reaction medium resulted in the formation of pure RGO with reduced O-content and flat nanosheet-like morphology (Amm-RGO(3/2)). Interestingly, few-layer graphene-like nanosheets with slight oxygen and amorphous carbon contents and few structural defects are produced when annealing Amm-RGO(3/2) at 600 degrees c under inert atmosphere. In summary, hydrothermal treatment of aqueous solution containing just glucose and ammonia followed by moderate-temperature thermal annealing, lead to few-layer graphene-like nanosheets with good structural characteristics. This new simple and efficient approach can be of great potential in the mass production of graphene-like nanosheets.
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