Cathodic micro-arc electrodeposition of yttrium stabilized zirconia (YSZ) coatings on FeCrAl alloy

Zirconia-based coatings, especially yttrium stabilized zirconia (YSZ), are the best ceramic coatings for high temperature applications due to their superior mechanical and thermal behavior[1]. And YSZ is of considerable in-terest for applications in solid-oxide fuel cells due to its high oxygen-ion conductivity and stability in oxidizing and reducing atmospheres, oxygen sensors and microelec-tronic devices[2]. The traditional methods to produce the YSZ coatings are plasma spray, electron be…     

Heteroseneous oxidation of carbonyl sulfide on mineral oxides

Heterogeneous oxidation of carbonyl sulfide （OCS） on mineral oxides including SiO2, Fe2O3, CaO, MgO, ZnO and TiO2, which are the main components of atmospheric particles, were investigated using in situ diffuse reflectance infrared Fourier transform spectroscopy （in situ DRIFTS）, ion chromatography （IC）, temperature-programmed desorption （TPD）, X-ray diffraction （XRD） and Brunauer-Emmett-Teller （BET） methods. The main products and intermediates of the heterogeneous oxidation of OCS on these oxides were identified with in situ DRIFTS and IC. The reaction mechanism and kinetics were also discussed. It is found that the reaction mechanism on these mineral oxides is the same as that on Al2O3 for the same final products and the intermediates at room temperature. Namely, OCS can be catalytically oxidized to produce surface SO4^2- species and gaseous CO2 through the surface hydrogen thiocarbonate （HSCO2-） and HSO; species. The activity series for heterogeneous oxidation of OCS follows： Al2O3 ≈ CaO 〉 MgO 〉 TiO2 ≈ ZnO 〉 Fe2O3 〉 SiO2. The specific area, basic hydroxyl and surface basicity of these oxides have effect on the reactivity. This study suggests that heterogeneous reactions of OCS on mineral dust may be an unneglectable sink of OCS.     

Multi-dimensional overall regulatory modes and threshold values for water cycle of the Haihe River Basin

In this study, a multi-dimensional critical regulatory criteria and decision-making mechanism based on the scientific cognition of multi-dimensional attributes and characteristics of the water cycle was proposed. This system was functioned by deeply discriminating the nature-society binary characteristics of the five-dimensional characteristics of the water cycle system of the Haihe River Basin (water resources, economy, society, ecology, and environment) under the influence of high-intensity human activities and hydrological changes and by analyzing the organic interactive relationships between the five dimensions and their overall effect on the water cycle. A GDP calculation model was constructed in this study by adjusting the water environment for water resources, after which five-dimensional normalization objective functions were established for multi-objective analysis to carry out trade-off analysis of multi-dimensional regulatory indexes. In addition, synergetic theory, entropy theory and dissipation structure theory were introduced to construct an evaluation model for multi-dimensional regulatory schemes. A water cycle multi-dimensional critical overall regulatory model system was also established. This system consisted of a multi-objective macroeconomic model (DAMOS), water resource allocation model based on rules (ROWAS), evaluation model for WEDP (EMW) and multi-dimensional regulatory scheme evaluation model (SEAMUR) as the main body. To address the national demands faced by the Haihe River Basin as a result of combinatorial schemes for different hydrological series and water amounts diverted by the south-to-north water diversion project, this study adopted a hierarchy progression method to set up the technologies, investigated multi-dimensional overall regulatory methods, proposed an overall regulation threshold value for the water cycle of the Haihe River Basin, and recommended corresponding five-dimensional regulatory schemes.     

Controlled assembly of gold and rare-earth upconversion nanoparticles for ratiometric sensing applications

In this paper, the Au nanoparticles and rare-earth (RE) upconversion nanoparticles (NPs) were respectively synthesized by using polyelectrolyte as the capping agents. Since the synthesized Au NPs and RE NPs had the similar size and surface conditions, Their mixture were employed in a pH sensing application. Benefited from the good spectral overlap between the RE upconversion emission bands and pH-tunable surface plasmon bands of the Au NPs, the pH-induced manipulation of green-to-red emission intensity ratio of the upconversion fluorescence was achieved in the Au-RE mixture. The results demonstrate a rapid ratiometric approach for pH sensing, which is more efficient than traditional sensing methods that depend on single intensity-based responses to analytes.     

温盐环流在百年尺度上影响中国气候的一个数值模拟证据

基于使用全耦合模式的末次冰消期(显著的全球增暖阶段)瞬变模拟结果, 通过敏感性试验明确指出温盐环流(Thermohaline Circulation, THC)在百年尺度上大幅度影响中国气候, 特别是在气候突变阶段. 结果表明, 该瞬变模拟中中国地区的气候演变符合古气候资料的纪录, 如Bølling-Allerød(BA)增暖事件期间中国地区的年平均气温大幅度升高; 在敏感性试验中, 当人为限制THC在BA事件期间的变化幅度时, 中国地区的升温幅度明显减小. 结果同时表明, 除温室气体、太阳辐射强度因素外, THC是另外一个在百年尺度上影响中国气候的重要因素.     

Advances in studies on hepatic stem cells

The question whether hepatic stem cells exist or not has been debated for several decades. Current researches confirm that there are hepatic stem cells in the liver. Oval cells, putative bipotential hepatic stem cells, are probably located within canals of Hering, portal tracts or branches of biliary trees. Bone marrow is a potential source of oval cells, indicating that there exists a close relationship between liver and hematopoiesis in adulthood. Hepatic stem cells are able to proliferate in vitro and can be induced to differentiate into hepatocytes. This will provide a promising approach of cell transplantation, tissue engineering and gene therapy for liver diseases. In this review, the evidence of their presence, origin, identification, proliferation in vitro, differentiation by induction, application prospects of hepatic stem cells and future directions for the field are discussed.     

Theoretical analysis of tissue axial stretching model in elastography

The performance of axial displacement estimation in ultrasound elastography can be degraded by tissue lateral displacements,mainly because of the move-in and move-out of tissue scatterers.In our previous work,a tissue axial stretching model was proposed to separate the decorrelation effect induced by lateral displacements from other decorrelation sources.In this paper,the tissue axial stretching model is analyzed theoretically.The theoretical result in a closed form indicates that the peak value of the cross-correlation function between the pre- and post-compression echoes is determined mainly by the beam width,the beam position and the lateral strain.Computer simulations are carried out to verify the theoretical conclusion.The theoretical analysis and simulation results can help to understand more clearly the decorrelation effect of tissue lateral displacements and the 2-D spatial comprehensive cross-correlation method presented previously to reduce the decorrelation effect     

Process of Petri Nets Extension

0Introduction Manynewcomputingplatforms,suchasthelocalareanetwork,Internetandthevirtualnetwork,arebeingcreatedandthenetworkcomputinghasbeenpopular.There fore,thesemanticsmodelbasedonsuchplatformsisdifferenttothetraditionalmodel.Comparedwiththetraditionalmodel,thenetworkcomputingmodelhastwospecialfeatures:first ly,computingunits(tofulfillatask)areallocatedonthedis tributedandindependentnodesandthesenodespossessre sourcesrespectively.Furthermore,thecentralcontrolnodeisnotnecessary.Secondly,thei…     

A Study of the Driving Force Model Revealing Changes in Land Utilization Level Based on 3S Technologies ——The Example of Yuanmou, Yunnan, China

0Introduction Landutilizationlevel(LUL)revealsthescopeanddepthoflandutilizationbyhumanbeings.Itrepresentsthecomprehensivecharacteristicoflandblendingnaturalfeatures,naturalenvironmentalfactors aswellassocialandeconomicfactors.Internalandexternalcausesresu…