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Weld-induced geometric distortion of plate between the stiffeners of friction stir welded (FSW) stiffened panel is idealized. The plate distortion magnitude is defined according to the statistical data from Paik's analysis results. By the use of finite element method (FEM), the stability performance of FSW stiffened panel subjected to longitudinal compression is calculated and the effects of plate distortion shapes and boundary conditions on the stability performance of the structure are analyzed. Calculation results show that, in general, the plate geometric distortion presented in this work increases the critical buckling load but reduces the ultimate strength of the structure. The plate distortion shape affects the buckling mode and buckling load as well as the ultimate strength of the structure. [ABSTRACT FROM AUTHOR]

To analyze the clinical features and laboratory test results of patients with autoimmune hepatitis ( AIH ) - primary biliary cirrhosis (PBC) overlap syndrome, as well as their correct diagnosis rate and time to diagnosis. Methods Fifty - three patients who were diagnosed by liver biopsy as having AIH - PBC overlap syndrome from January 2009 to June 2013 were selected as subjects; 53 AIH patients and 53 PBC patients were selected as control groups. Their clinical manifestations, laboratory test results, and diagnosis on admission were retrospectively analyzed. Comparison of normally distributed quantitative data between groups was made by one - way analysis of variance, and multiple comparisons were made by SNK - q test ; comparison of qualitative data between groups was made using RxC contingency table, and multiple comparisons were made by Scheffe's confidence interval test. Results The 53 patients with AIH - PBC overlap syndrome had a serum alanine aminotransferase level of 173. 65 ±52. 08 U/L, a serum total bilirubin level of 38. 07 ± 6. 82 μmo/L, a serum alkaline phosphatase ( ALP) level of 293. 81 ± 28. 89 U/L, and a serum gamma - glutamyl transpeptidase level of 57. 57 ±78. 84 U/L. ALP showed significant difference between the patients with AIH - PBC overlap syndrome and control groups. The serum level of immunoglobulin M in overlap syndrome patients was 3. 33 ±2. 12 g/L, which was significantly different from those of two control groups. Of the 53 overlap syndrome patients, 27 were positive for anti - mitochondrial antibody - M2, and the positive rate was significantly different from those of two control groups. Without liver biopsy, the correct diagnosis rate was the lowest (52. 83% ), and it took the longest time (8 ±7.7 d) to confirm the diagnosis on admission. Conclusion The clinical manifestations of patients with AIH - PBC overlap syndrome are more similar to those of PBC patients, but their biochemical test results are more similar to those of AIH patients. AIH - PBC overlap syndrome has the clinical features of both AIH and PBC. [ABSTRACT FROM AUTHOR]

The coal rich in semi-fusinite was selected to run liquefaction rests in tubing-bomb reactors in a pre-heated sand bath. The petrological features of liquefaction residues were observed by microscopy, and the comparative discussion on chemical structure on raw coal and relatively liquefaction residues were presented by using FF-IR, 13C-NMR, and Py-GC/MS techniques. The results show that the liquefaction conversion reaches to more than 50% although coal used with high semi-fusinite content. The optical examination of liquefaction residues show that the partial semi-fusinites become plastic, and even formes hollow spheres, which indicate that semi-fusinites have involved in the liquefaction reaction. The comparison of chemical structure of raw coal and relatively liquefaction residues clearly show that the changes of chemical structures during liquefaction are occurred. Furthermore, the results of Py-GC/MS show that the compounds in residue are mainly composed of alklynaphthalene, C2-naphthalene and C3-naphthalene are main constitutions. Finally, the role of semi-fusinite in liquefaction was further discussed according to the results of speculation and petrological features. [ABSTRACT FROM AUTHOR]

To describe the mechanical behavior of NEPE propellant under finite deformation condition,a viseo-hyperelastic constitutive equation was proposed. The equation comprises two parts--a component based on Yeoh strain energy function to characterize the static hyperelastic behaviour, and another to define nonlinear viscoelastic behaviour. The tensile test and relaxation test were employed to determine the parameters in the constitutive relationship. The comparison between the predicted results based on the proposed model and the experimental results shows that it is able to aptly describe the visco-hyperelastic behaviour of NEPE propellant. [ABSTRACT FROM AUTHOR]

In order to find new drugs combined with the sensitive targets to solve the problem of drug resistance of pathogenic bacteria, by constructing the overexpression strain of the outer membrane protein ompC of Escherichia coli, the killing effect of gentamicin on it was tested and compared with that of the wild-type Escherichia coli. Then, the relationship between the protein expression level of ompC and the killing effect of gentamicin was explored by vising the immunoblot assay, and the over-expression strain MIC was further determined. The results showed that the overexpression of ompC could significantly enhance the sensitivity of Escherichia coli to gentamicin, and after the overexpression of ompC, the minimum inhibitory concentration of the strain W3110-pCA24N (ompC) was 8 ug • mL-1, which was significantly lower than that of the strain W3110-pCA24N (wild type) (being 16 ug • mL-1). The gentamicin was more intaken into the cells of Escherichia coli, which enhanced the bactericidal effect of gentamicin. Therefore, the outer membrane protein was expected to be a new candidate target of drug sensitivity. [ABSTRACT FROM AUTHOR]

As the steps for the design and manufacture of the die increase, it is more and more possible to have hardware Trojans implanted in the chip. So it is necessary to detect the hardware Trojans for the die, especially with high security requirements. Reversely anatomizing the die and comparing it with the original GDSII file on the consistency is one of the main methods to test whether the die has been implanted hardware Trojans or not. It is an important step to generate the pictures from the GDSII file and make the pictures correspond to the photos which are got by reversely anatomizing the die. Therefore, we propose a two-point position algorithm for the segmentation of GDSII pictures. Meanwhile, for the position offset of the picture information generated in the process o£ taking photos of die and splicing, we propose a correction algorithm based on deviation statistics. Engineer practical application proves that the algorithm revises the deviation between the pictures generated from GDSII file and the photos of the die well. And it eliminates the impact from the position offset of the picture information. [ABSTRACT FROM AUTHOR]

The macerals of bark liptobiolite of Leping Mine in Jiangxi Province were separated by the method of Density Gradient Centrifugation, and the density distribution characteristic curves of coal of -200 mesh was drawn through analytical pre-separation experiments. The curves shows that the density distribution of liptinite and vitrinite of bark coal is relatively concentrated; it's easy to separate specific macerals; while inertinite and vitrinite are so intermixed that the separation is less effective. The content of barkinite and vitrinite reaches over 98.6% after the particular Density-gradient Centrifugation separation experiments. There are obvious differences between the two macerals of the separated samples in the chemical structure according to the high resolution TEM and image analysis: First, the number of the lattice fringes of barkinite is significantly greater than that of vitrinite, and the lattice fringes of barkinite are equipped with a characteristic of more disordered and concentrated; secondly, the proportion of different lattice fringes of vitrinite and barkinite is relatively close to each other, short aromatic fringe is dominant for both, while the difference is that the content of 1 x 1 (naphthalene) of vitrinite is obviously greater than that of barkinite, but the 3x3 aromatic fringe displays a completely opposite characteristic. The content of medium-long aromatic fringe is not high, but this value of barkinite is also significantly lower than that of vitrinite. [ABSTRACT FROM AUTHOR]

Thirty-three Phylostachys edulis germplasms from 11 provenances in Guangxi were analyzed by AFLP markers Five pairs of primer combination were used to amplify the genomic DNA. A total of 198 AFLP bands were obtained, 47 (23.74%) of them were polymorphic The genetic distance between the 11 provenance ranged from 0.006 to 0.136 9. The tested gemplasms can be divided into 4 categories by UPGMA cl ustering analysis Nandan and Zhaoping provenances were clustered into two categories respectively They were distinct to other two categories PCA analysis results were consistent with the results of cluster analysis Mantel test results showed that the corela tions between genetic distance and geographic distance in P. edulis provenance sources were significant (r = 0.555 8, P = 0.555 8), and AFLP was an effective marker to identify germplasm of P. edulis. [ABSTRACT FROM AUTHOR]

The constant rate uniaxial tension tests and tension-recover tests are conducted to obtain the accurate mechanical property of the EPDM insulation material. A visco-hyperelastic constitutive model is developed based on the mechanical behavior characteristics of EPDM. The method is established by applying the hyperelastic theory which was established under finite deformation condition in combination with linear viscoelastic theory. Then the way to obtain the model parameters is proposed, which is simple and easy to be generalized. The results show that EPDM has the typical hyperelastic mechanical characteristics, and presents a rate-dependent effect. The visco-hyperelastic constitutive model proposed can describe the uniaxial mechanical property of EPDM accurately. The model can provide a theoretical reference for structural integrity analysis of solid rocket motor made of EPDM insulation material. [ABSTRACT FROM AUTHOR]

Aircraft structural life envelope (ASLE) is a boundary line of fatigue life and calendar life while aircrafts in service. Based on the concept of ASLE, and considering the interaction between fatigue life and calendar life, a method of determining ASLE by pre-corrosion fatigue tests is proposed as corrosion-affecting coefficient method. A residual life prediction method for corrosion-fatigue critical components of aircraft metal structures under typical environment is established, and a residual life prediction example under condition of variable flight intensities is presented. The establishment of ASLE will pave the way for the structural life (i. e. fatigue life and calendar life) supervision for individual aircraft. [ABSTRACT FROM AUTHOR]

Nine standard coal samples from different coalbeds of Zhongliangshan southern coal mine in Huayingshan coalfield were tested using the low-temperature nitrogen adsorption method to study the fractal characteristics of adsorption pores (pore diameter <100 nanometers) and the relationship between fractal dimension and the gas adsorption capacity of tectonic coal. The results of both the low-temperature nitrogen adsorption and desorption show that different deformed coal has different adsorption characteristics under relative pressures between 0.5-1.0. Based on the results, the fractal dimension D of tectonic coal was studied using the fractal Frenkel-Halsey-Hill (FHH) method. The results demonstrate that the fractal dimension D can represent the variation characteristics of pore structure and pore surface area of tectonic coal. The higher fractal dimension D, the more micropores, the more irregular specific coal surface, and the higher heterogeneity of pore structure. The gas storage capacity of coal can be represented by the fractal dimension D, and the gas adsorption capacity of coal increases with the increasing of fractal dimension D. Therefore, the higher fractal dimension and the more homogeneous pore structure resulting from strong tectonic deformation, indicate that the coal has a higher gas adsorption capacity. [ABSTRACT FROM AUTHOR]