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Previous researches mainly focused on the cooling performance of the vortex tube. Here, the heating performance indicators such as hot temperature difference, heating rate per unit air, and coefficient of performance are investigated experimentally. The results show that the maximum heating separation is obtained when the cold mass fraction is in the range of 0.45-0.7. The influence of inlet pressure on the hot temperature difference tends to reduce when it exceeds 0.3 MPa. Increase of the inlet pressure will cause the decrease of heating rate. Compared with 4-nozzle vortex tube, much better performance is achieved when 6-nozzle vortex tube is used. [ABSTRACT FROM AUTHOR]

Angle‐domain common‐image gathers are an important tool in the post‐processing of seismic images and for reservoir characterization. The generation of angle gathers is a very important issue when dealing with angle‐domain images. Efficiency and robustness are the main concerns in the generation of angle gathers. In this paper, we propose two methods for producing angle gathers based on the implementation of a reverse‐time migration. In the hybrid method, we adopt the local‐plane‐wave decomposition method to extract the local plane waves and obtain two possible opposite propagation directions in the time‐wavenumber domain. Then, Poynting vectors are used to determine the correct propagation direction. The hybrid method achieves a satisfactory balance between robustness and computational efficiency. Furthermore, in the improved hybrid method, additional computational acceleration is obtained by separating the overlapping and non‐overlapping wavefield areas. The hybrid method is only applied in these areas with overlapping wave fronts, and the Poynting‐vector‐based method is adopted in the other areas. The location of the overlapping events is determined using the eigenvalues of the structural tensor. Finally, the two‐dimensional synthetic and field examples demonstrate the effectiveness of both methods. [ABSTRACT FROM AUTHOR]

For linear noise such as seismic ground roll, 3-D frequency-wavenumber-wavenumber (3-D FKK) domain filtering suppression is better than 2-D frequency-wavenumber (F-K) domain filtering. In recent years, with the continuous development of computer processing speed and memory capacity, high-density data acquisition in seismic exploration has been widely applied in the hydrocarbon industry, opening up the application of 3-D FKK filtering methods. We applied the 3-D FKK filtering software to a 3-D high-density onshore seismic field dataset from a coal mine in western China. The case study demonstrates that the linearity of the noise in the field data is better represented by constructing the single shot records as a minimum dataset. Both theoretical synthetic models and the 3-D high-density onshore seismic field data numerical filtering experiments demonstrate that the feasibility of 3-D FKK filtering. [ABSTRACT FROM AUTHOR]

Three-dimensional seismic survey is widely applied, but 3-D filtering technology has yet to be fully utilized for the analysis of seismic field data. The common approach is to first filter inline and then crossline. However, an effective 3-D filtering method is expected to eliminate coherent noise, such as the ground roll. We propose a 3-D Butterworth filtering method in the time-space domain. Firstly, a Butterworth-type filter in the frequency-wavenumber-domain is designed to suppress the linear noise with a specific apparent velocity. Secondly, transforming this filter to the time and space domain yields 3-D partial differential equations (PDEs), which are applied to suppress the linear noise. Factorizing the finite-difference equations in a different direction other than decreasing the 3-D PDEs to 2-D PDEs produces a highly accurate and efficient algorithm. Designing the 3-D Butterworth filter, selecting the filtering parameters, and showing its application to synthetic data and a 3-D high-density onshore seismic field data from a region in western China are discussed in detail. Numerical experiments with 3-D high-density onshore seismic field data demonstrate that it is more effective than the 3-D frequencywavenumber- wavenumber (FKK) filtering method. [ABSTRACT FROM AUTHOR]

We applied Zelt's new frequency-dependent traveltime tomography (FDTT) method to 2D crosswell seismic field data from an eastern oil field in China. The FDTT uses the frequency content in the seismic waves in both the forward and inverse modeling steps. Although FDTT only uses a 300 Hz frequency to invert the dataset, the degree of matching between the inverted layers from FDTT and that of a sonic well logging curve is high, which shows that FDTT provides a high resolution reconstruction of subsurface structure through the simple use of the first-arrival traveltime data. The case study demonstrates that the FDTT algorithm is practical and can stand up to the complexities of a real 2D crosswell dataset. Additionally, we show that the FDTT method can create a high resolution long wavelength velocity model. [ABSTRACT FROM AUTHOR]

Background: Autophagy-related ATG6 proteins are pleiotropic proteins functioning in autophagy and the phosphatidylinositol 3-phosphate-signaling pathways. Arabidopsis ATG6 regulates normal plant growth, pollen development and germination, and plant responses to biotic/abiotic stresses. However, the ATG6 functions in wheat (Triticum aestivum L.), an important food crop, are lacking. Results: We identified three members, TaATG6a-6c,o ft h e ATG6 family from common wheat. TaATG6a, 6b and 6c were localized on homeologous chromosomes 3DL, 3BL and 3AL, respectively, of the allo-hexaploid wheat genome, and evidence was provided for their essential role in autophagy. The TaATG6a-GFP fusion protein was found in punctate pre-autophagosomal structures. The expression of each TaATG6 gene restored the accumulation of autophagic bodies in atg6-mutant yeast. Additionally, TaATG6 knockdown plants showed impaired constitutive and pathogen-induced autophagy and growth abnormalities under normal conditions. We also examined the expression patterns of wheat ATG6s for clues to their physiological roles, and found that their expression was induced by the fungus Blumeria graminis f. sp. tritici (Bgt), the causal agent of powdery mildew, and by abiotic stress factors. A role for TaATG6s in wheat immunity to powdery mildew was further implied when knockdowns of TaATG6s weakly compromised the broad-spectrum powdery mildew resistance gene Pm21-triggered resistance response and, conversely and significantly, enhanced the basal resistance of susceptible plants. In addition, leaf cell death was sometimes induced by growth-retarded small Bgt mycelia on susceptible TaATG6 knockdown plants after a long period of interaction. Thus, we provide an important extension of the previous characterization of plant ATG6 genes in wheat, and observed a role for autophagy genes in wheat immune responses to fungal pathogens. Conclusions: Three wheat ATG6s were identified and shown to be essential for autophagy biogenesis. Wheat ATG6s are implicated in immunity to powdery mildew, playing a weak, positive role in the Pm21-triggered resistance response and a negative role in the basal resistance of susceptible plants. [ABSTRACT FROM AUTHOR]

In this paper, source-receiver migration based on the double-square-root one-way wave equation is modified to operate in the two-way vertical traveltime (τ) domain. This tau migration method includes reasonable treatment for media with lateral inhomogeneity. It is implemented by recursive wavefield extrapolation with a frequency-wavenumber domain phase shift in a constant background medium, followed by a phase correction in the frequency-space domain, which accommodates moderate lateral velocity variations. More advanced τ-domain double-square-root wave propagators have been conceptually discussed in this paper for migration in media with stronger lateral velocity variations. To address the problems that the full 3D double-square-root equation prestack tau migration could meet in practical applications, we present a method for downward continuing common-azimuth data, which is based on a stationary-phase approximation of the full 3D migration operator in the theoretical frame of prestack tau migration of cross-line constant offset data. Migrations of synthetic data sets show that our tau migration approach has good performance in strong contrast media. The real data example demonstrates that common-azimuth prestack tau migration has improved the delineation of the geological structures and stratigraphic configurations in a complex fault area. Prestack tau migration has some inherent robust characteristics usually associated with prestack time migration. It follows a velocity-independent anti-aliasing criterion that generally leads to reduction of the computation cost for typical vertical velocity variations. Moreover, this τ-domain source-receiver migration method has features that could be of help to speed up the convergence of the velocity estimation. [ABSTRACT FROM AUTHOR]

A full-length cDNA encoding wheat peroxisomal ascorbate peroxidase (pAPX) was cloned by Suppression Subtractive Hybridization (SSH) and in silico approach. The cDNA was 1027 bp in length and contained a complete ORF of 876 bp, which encodes a protein of 292 amino acid residues. Its deduced amino acids sequence had 84% identity with that of pAPX from barley. The gene was designated as Ta-pAPX. The Ta-pAPX homologous genes were mapped on wheat chromosome 7A and 7D using Chinese Spring nulli-tetrasomic lines analysis. Northern analysis indicated that, after inoculation by Erysiphe graminis Dc.f.sp. tritici, the expression of Ta-pAPX gene in Yangmai5 was enhanced, but its expression in wheat-Haynaldia villosa 6VS/6AL translocation lines changed a little. The results implied that Ta-pAPX may be related to susceptibility of wheat to powdery mildew. The complete coding sequence of Ta-pAPX was cloned into an expression vector pET32 (a+) and a protein with the same deduced molecular weight (MW) was expressed in E. coli BL21 (DE3), which showed ascorbate peroxidase activity. [ABSTRACT FROM AUTHOR]

Presents a study that evaluated the performance of the HT-7U data system, a computer system designed to provide effective distributed data acquisition and processing. Features of the HT-7U data system; Details of the operation modes of the system; Information on the models of acquisition on the computer automated measurement and control subsystems of the HT-7U data system.