An optimization approach to the similarity criteria of flows and its application

In the present paper, we propose an optimization approach to investigate the similarity criteria of complex flows. With this approach, we may identify the dominant dimensionless variables governing complex flows by numerical sensitivity analysis. Firstly, we define the sensitivity factor and examine its dependence on the dimensionless variables. Then, we apply this approach to study the similarity criteria of porous media flow in a presumed oil reservoir. The similarity principle obtained from the numerical sensitivity analysis is in agreement with the theoretical law, thus demonstrating the feasibility of the proposed optimization approach. Further explanation is given by analyzing the deviation of pressure distribution in a model from its prototype. In addition, we examine the effects of flow parameter variation on the sensitivity factors and find that the dominant dimensionless variables may change from different sets of parameters.     

Fabrication of cotton nano-powder and its textile application

A combination of chemical and mechanical treatment of cotton produced cotton powder （fibrils） with a mean diameter of 97 nm is analyzed by Laser Particle Size Analyzer. Transmission Electron Micro- scope （TEM） study showed that the diameter of the fibrils was about 10--30 nm and the length was from 70nm to over 400 nm. The powder was then coated onto fabrics （100% polyester fabric, 100% wool fabric and 100% cotton fabric）. Scanning Electron Microscope （SEM） study showed that cotton fibrils were adhered to the surface of treated fabrics （fibers）. The ultraviolet protection factor （UPF） value （AS/NZS 4399： 1996） for cotton fabrics increased about 20% after the treatment. This implies that the treated samples give a better protection from UV light. The moisture management test （MMT） of the fabrics such as wetting time at bottom, top maximum absorption rate, bottom maximum absorption rate, bottom maximum wetted radius and bottom spreading speed, et ah, showed that there were significant changes after the treatment. These changes gave better moisture management ability to the treated fabrics and thus made the fabric more comfortable. However, Wide-angle X-ray Diffraction and Fourie Transform Infrared Spectroscopy analysis proved that supermolecular structure and chemical struc- ture of treated fabrics were the same as the original fabrics. Other properties of the treated fabric such as thermal conductivity, wrinkle recovery, hand, et al., did not change. This implied that the basic func- tion of the treated fabrics for the clothing industry was the same as untreated fabrics. This study is a foundation for further researches on textile application.     

Matrix equation and its application to classification of finite-dimensional estimation algebras

Under a very natural condition, a matrix equation is proved to have only trivial solution. This result is then applied to the classification problem of finite-dimensional estimation algebras, which gives a simpler proof of Tang s recent result on the constant structure of the O~matrix.     

Relative damage stress and its application in the case of temperature cycling load

Void damage is the main failure characteristics of constrained ductile metal foil. In order to evaluate the mechanical response of ductile metal under different temperatures, the concept of equivalent damage stress proposed by Lemaitre is modified by temperature normalization. A new concept of relative damage stress is advanced, and in the light of this concept, a reasonable explanation is given to the thermal fatigue life data of solder joints under temperature cycling.     

A two-stage algorithm of adaptive model-based parameter estimation and its application in the fast calculation of Green''s function in multi-layer soils

A two-stage algorithm is presented to determine an analytical model-based rational function by adaptively selecting sampling points. At the first stage, the rational interpolation function is created by using Stoer-Bulirsch algorithm and comparing the fitted model with the different ranks. At the second stage, the fitted model is validated by comparing with the first-principle model at a set of checking points. Some checking points will be added to the sampling series determined in the first stage to improve the fitted model. The new proposed algorithm is more accurate and effective than that using Stoer-Bulirsch interpolation only due to the fact that it appends the validation approach. When a highly oscillating curve is approximated, the validation ensures the fitting precision. With the two-stage MBPE algorithm, some time-consuming electromagnetic computations can be replaced by the interpolation from the fitting functions, which can increase the computational efficiency greatly. This method is used to calculate the samplings of the Green's functions in a multi-layer horizontal soil to demonstrate its effectiveness. The number of samples used to accurately model such Green's functions is less than 20 for the typical soil parameters. The computational time can be reduced by more than two orders of magnitude compared with that using the conventional uniform sampling technology.     

Preparation of Zn-doped TiO2 nanotubes electrode and its application in pentachlorophenol photoelectrocatalytic degradation

Zn-doped titanium oxide （TiO2） nanotubes electrode was prepared on a titanium plate by direct anodic oxidation and immersing method in sequence. Field emission scanning electron microscopy （FESEM） showed that the Zn-doped TiO2 nanotubes were well aligned and organized into high density uniform arrays with diameter ranging from 50 to 90 nm. The length and the thickness were about 200 and 15 nm respectively. TiO2 anatase phase was identified by X-ray diffraction （XRD）. X-ray photoelectronspectroscopy （XPS） indicated that Zn ions were mainly located on the surface of TiO2 nanotubes in form of ZnO clusters. Compared with TiO2 nanotubes electrode, about 20 nm red shift in the spectrum of UV-vis absorption was observed. The degradation of pentachlorophenol （PCP） in aqueous solution under the same condition （initial concentration of PCP： 20 mg/L; concentration of Na2SO4：0.01 mol/L and pH： 7.03） was carried out using Zn-doped TiO2 nanotubes electrode and TiO2 nanotubes electrode. The degradation rates of PCP using Zn-doped TiO2 nanotubes electrode were found to be twice and 5.8 times as high as that using TiO2 nanotubes electrode by UV radiation （400 μw/cm^2） and visible light radiation （4500 μw/cm^2）, respectively. 73.5% of PCP was removed using Zn-doped TiO2 nanotubes electrode against 45.5% removed using TiO2 nanotubes electrode in 120 min under UV radiation. While under visible light radiation, the degradation efficiency of PCP was 18.4% using Zn-doped TiO2 nanotubes electrode against 3.2% using TiO2 nanotubes electrode in 120 min. The optimum concentration of Zn doping was found to be 0.909%. The PCP degradation efficiencies of the 10 repeated experiments by Zn-doped TiO2 nanotubes electrode were rather stable with the deviation within 3.0%.     

Partial continuation model and its application in mitigating systematic errors of double-differenced GPS measurements

Based on the so-called partial continuation model with exact finite measurements, a new stochastic assessment procedure is introduced. For every satellite pair, the temporal correlation coefficient is estimated using the original double-differenced (DD) GPS measurements. And then, the Durbin-Watson test is applied to test specific hypothesis on the temporal correlation coefficient. Unless the test is not significant with a certain significant level, a data transformation is required. These transformed measurements are free of time correlations. For purpose of illustration, two static GPS baseline data sets are analyzed in detail. The experimental results demonstrate that the proposed procedure can mitigate effectively the impact of systematic errors on DD GPS measurements.     

Preparation and performance of lipophilic α-zirconium phosphate with high thermal stability and its application in thermal-plastic polymers

To prepare lipophilic α-zirconium phosphate with high grafting ratio and thermal stability(OZrP-HT) and explore its potential application in thermal-plastic polymers,a novel method was developed by surface lipophilicity enhancement strategy.The commercial a-zirconium phosphate(a-ZrP) was pre-intercalated by n-propylamine(PA) and grafted by silane coupling agents.Then the pre-intercalated PA was removed by heattreatment,and the obtained OZrP-HT was utilized to fabricate the phosphorous-containing polyester(P-co-PET)/OZrP-HT nanocomposites by melt-blending method.The prepared OZrP-HT and P-co-PET/OZrP-HT nanocomposites were characterized by Wide Angle X-ray Diffraction(WAXD),Fourier Transform Infrared Spectroscopy(FTIR),Thermogravimetric Analysis(TGA),Transmission Electron Microscope(TEM),etc.The results show that OZrP-HT with high grafting ratio(13.78 wt%) and thermal stability(T_(onset)= 368℃) was successfully prepared via this novel method and was uniformly intercalated by P-co-PET molecular chains.OZrP-HT had no significant effect on the fiber processability of P-co-PET polymer,and flame retardant properties of(P-co-PET)/OZrP-HT nanocomposites were improved.This method may be suitable for organic modification of general inorganic layered compounds and could extend the potential applications in thermo-plastic polymers.     

Coherent thermal radiation in thin films and its application in the emissivity design of multilayer films

The infrared transmission spectra of a 0.54-μm-thick Ge film and a 20-μm-thick Si film were experimentally measured. As the incident radiation was in the wavelength range from 1.5μm to 10μm, the Ge film demonstrated a strongly spectral coherence. However, thermal radiation of the Ge film was found to be spatially incoherent due to its extreme thinness. The Si film exhibited significantly spectral and spatial coherence. The results confirmed that thermal radiation of a monolayer film could be coherent spectrally and spatially if the film thickness was comparable with the wavelength. The optical characteristic matrix method was applied to calculate the transmission spectra of the Si and Ge film, and the results agreed well with the measurements. This method was further used to analyze two multilayer films composed of five low emissive layers. Their emissivities were found to be highly emissive at a certain zenith angle, and the emissive peak could be controlled by careful selection of film thickness.     

PCR—RFLP analysis of mitochondrial DNA ND5／6 region among3 subspecies of common carp（Cyprinus carpio L.）and its application to genetic discrimination of subspecies

Mitochondrial DNA ND5/6 region was studied by PCR-RFLP analysis among ten representative strains belonging to three subspecies (Cyprinus carpio carpio,Cyprinus carpio haematopterus and Cyprinus carpio rubrofuscus) of common carp(Cyprinus carpio L.)A total of 2.4kb fragment was amplified and subjected to restriction endonuclease analysis with nine restriction endonucleases subsequently.The results indicated that each subspecies owned one hyplotype and four restriction enzymes(Dde Ⅰ，HaeⅢ,Taq Ⅰ and MboⅠ)produced diagnostic restriction sites which could be used for discriminating the three subspecies and as molecular genetic markers for assistant selective breeding of common carp.     

Modification of a viral satellite DNA-based gene silencing vector and its application to leaf or flower color change in Petunia hybrida

Gene silencing conserved in plants and animals is mediated by mechanisms that involve sequence- specific RNA degradation[1,2]. Gene silencing has been proven to play an important role in the study of gene function. Recently, a procedure known as virus ind…     

Separation and analysis of the soluble trimer of Aβ1-40 and its effects on the rise in intracellular calcium

Alzheimer’s disease (AD) is one of the progressive neurodegenerative diseases associated with protein conformational transition, generally known as protein conformational disorders[1]. The general characteriza- tions of AD are the intracellular fibrillar…     

A detailed Lower Triassic conodont biostratigraphy and its implications for the GSSP candidate of the Induan–Olenekian boundary in Chaohu, Anhui Province

Chaohu is located in a deep part of carbonate ramp on the Lower Yangtze Block, which belonged to the low-latitude eastern Tethyan archipelago during the Early Triassic. Fossils were very rich in the Lower Triassic of Chaohu. Bivalves, ammonoids, conodonts were very common throughout the Lower Triassic, while fish fossils were generally rich in some beds of the upper part. It is one of the most typical sections for the Early Triassic chronostratigraphy in the world. Although various fossils had been studied in the 1980s and 1990s, recent studies based upon new and more detailed collections from the Lower Triassic of Chaohu showed that the conodont zonation needs revision. We collected Lower Triassic conodont fossils from continuous sections of the West Pingdingshan, North Pingdingshan and South Majiashan, Chaohu, Anhui Province, and updated zonations were made for each section. Eight conodont zones have been distinguished. They are, in ascending order, Hindeodus typicalis zone, Neogondolella krystyni zone, Neospathodus kummeli zone, Neospathodus dieneri zone, Neospathodus waageni zone, Neospathodus pingdingshanensis zone, Neospathodus homeri zone, and Neospathodus anhuinensis zone. The first occurrence of Neospathodus waageni eowaageni of the N. w. eowaageni subzone （i.e. the base of the N. waageni zone） is suggested as the marker to define the Induan-Olenekian boundary.     

A detailed Lower Triassic conodont biostratigraphy and its implications for the GSSP candidate of the Induan–Olenekian boundary in Chaohu, Anhui Province

Chaohu is located in a deep part of carbonate ramp on the Lower Yangtze Block, which belonged to the low-latitude eastern Tethyan archipelago during the Early Triassic. Fossils were very rich in the Lower Triassic of Chaohu. Bivalves, ammonoids, conodonts were very common throughout the Lower Triassic, while fish fossils were generally rich in some beds of the upper part. It is one of the most typical sections for the Early Triassic chronostratigraphy in the world. Although various fossils had been studied in the 1980s and 1990s, recent studies based upon new and more detailed collections from the Lower Triassic of Chaohu showed that the conodont zonation needs revision. We collected Lower Triassic conodont fossils from continuous sections of the West Pingdingshan, North Pingdingshan and South Majiashan, Chaohu, Anhui Province, and updated zonations were made for each section. Eight conodont zones have been distinguished. They are, in ascending order, Hindeodus typicalis zone, Neogondolella krystyni zone, Neospathodus kummeli zone, Neospathodus dieneri zone, Neospathodus waageni zone, Neospathodus pingdingshanensis zone, Neospathodus homeri zone, and Neospathodus anhuinensis zone. The ?rst occurrence of Neospathodus waageni eowaageni of the N. w. eowaageni subzone (i.e. the base of the N. waageni zone) is suggested as the marker to de?ne the Induan–Olenekian boundary.     

Urban structure and the risk of influenza A （H1N1） outbreaks in municipal districts

Changsha was one of the most affected areas during the 2009 A （H 1N 1） influenza pandemic in China. Here, we analyze the spatial-temporal dynamics of the 2009 pan- demic across Changsha municipal districts, evaluate the relationship between case incidence and the local urban spatial structure and predict high-risk areas of influenza A （H1NI）. We obtained epidemiological data on all cases of influenza A （H1NI） reported across municipal districts in Changsha dur- ing period May 2009-December 2010 and data on population density and basic geographic characteristics for 239 primary schools, 97 middle schools, 347 universities, 96 mails and markets, 674 business districts and 121 hospitals. Spatial- temporal K functions, proximity models and logistic regres- sion were used to analyze the spatial distribution pattern of influenza A （H1N1） incidence and the association between influenza A （HINI） cases and spatial risk factors and predict the infection risks. We found that the 2009 influenza A （H 1N 1 ） was driven by a transmission wave from the center of the study area to surrounding areas and reported cases increased significantly after September 2009. We also found that the distribution of influenza A （H 1N1） cases was associ- ated with population density and the presence of nearest public places, especially universities （OR = 10.166）. The final pre- dictive risk map based on the multivariate logistic analysis showed high-risk areas concentrated in the center areas of the study area associated with high population density. Our find- ings support the identification of spatial risk factors and high- risk areas to guide the prioritization of preventive and miti- gation efforts against future influenza pandemics.     

Development of Triticum aestivum-Leymus racemosus ditelosomic substitution line 7Lr#1S（7A） with resistance to wheat scab and its meiotic behavior analysis

Leymus racemosus is highly resistant to wheat scab （Fusarum head bright）. The transfer of scab resistant gene from L. racemosus to Triticum aestivum is of great significance for broadening the base of wheat resistance. In the present study, the pollen of T. aestivum-L, racemosus monosomic addition line with scab resistance was treated by irradiation with 1200 R ^60Co-γ-rays prior to pollinating to emasculated wheat cv. Mianyang 85-45. Nine plants with a telocentric chromosome 7Lr#1S were observed in M1, and one ditelosomic substitution line 7Lr#1S was selected from selfcrossing progenies and confirmed by chromosome C-banding and GISH. Furthermore, a co-dominant EST-SSR marker CINAU 31 was employed to identify this substitution line. A pair of chromosome 7A of common wheat were found to be replaced by a pair of telocentric chromosome 7Lr#1S, and further investigation showed that chromosome configuration of the substitution line at MI of PMCs after GISH was 17.50Ⅱ^w ＋ 2.19Ⅱ^w ＋ 0.42Ⅱ^7Lr#1S ＋ 1.08 Ⅰ^7Lr#1S ＋ 0.69 Ⅰ^w. Two telocentric chromosomes paired as a bivalent in 59.7% of PMCs. Abnormal chromosome behaviors of telocentric chromosomes were observed in part of PMCs at anaphase I and telophase I, including the moving of two telocentric chromosomes to the same pole, lagging and earlier separation of their sister chromatid. All these abnormal behaviors can be grouped into three distinct types of tetrads according to different numbers of 7Lr#1S in their daughter cells and various micronucleus in some tetrads. However, due to the high transmission frequency of the female and male gametes with a 7Lr#1S, 84% of the selfcrossing progeny plants had ditelosomic substitution. The substitution line showed high resistance to wheat scab in a successive two-year test both in the greenhouse and field; hence, the line will be particularly valuable for alien gene mapping, small fragment translocation induction and telosomic cytological behavior analysis.