Research on forming quality of poly-wedge pulley spinning

As an important power transmission part, pulleys are widely used in automobile industry, agricultural machinery, pumps and machines. A near-net forming process for six-wedge belt pulleys manufacturing was put forward. For this purpose, the required tooth shape and size can be formed directly by spinning without machining. The whole manufacturing procedures include blanking, drawing and spinning. The spinning procedure includes five processes, performing, drumming, thickening, toothing and finishing. The forming defects occurred during each forming processes of poly-wedge pulley spinning, such as the drumming failure, flanged opening-end, folded side-wall, insufficient bottom size, flashed opening-end, cutting-off bottom, are introduced, and the factors influencing the defects are analyzed. The corresponding preventive measures are put forward

MODEL OF WORKING SHIP CROSSING CHANNEL

An application method for working ship crossing safely is proposed to determine how to make navigation scheme at a certain time. This method makes it possible for decision makers to make reasonable judgments at different times. In this paper, the position relationship between working ship and navigation vessel in waterway is analysed by considering the ship size, hydrological conditions of waterway, ship arrival model and ship navigation trajectory. Using genetic algorithm, the operation scheme of keeping a safe distance between the working ship and the vessel in the channel is solved by taking the speed and direction of the working ship as genetic factors. By analysing the crossing scheme at each starting time in a given time range, the optimal crossing scheme with the farthest distance between the working ship and the vessels in the channel is obtained. According to the measured data, the simulation is carried out with MATLAB to verify the model of working ship crossing channel. The results show that it is safe and reliable to choose the navigation scheme proposed in this paper, which has strong application value

(Z)-1-[4-Fluoro-2-(pyrrolidin-1-yl)phen­yl]-3-phenyl-2-(1H-1,2,4-triazol-1-yl)prop-2-en-1-one

In the title mol­ecule, C21H19FN4O, the triazole ring forms dihedral angles of 67.0 (1) and 59.6 (1)° with the phenyl and fluoro-substituted benzene rings, respectively. The dihedral angle between the phenyl ring and the fluoro-substituted benzene ring is 79.1 (1)°. The pyrrolidine ring is in a half-chair conformation. In the crystal, weak C—H⋯O and C—H⋯N hydrogen bonds connect mol­ecules into layers parallel to (001)

N′2,N′5-Bis[(E)-2-hy­droxy­benzyl­idene]-3,4-dimethyl­thio­phene-2,5-dicarbohydrazide

In the title mol­ecule, C22H20N4O4S, both C=N bonds are in an E conformation. The benzene rings form dihedral angles of 12.10 (13) and 25.17 (12)° with the thio­phene ring. The dihedral angle between the two benzene rings is 17.59 (14)°. There are two intra­molecular O—H⋯N hydrogen bonds. In the crystal, N—H⋯O hydrogen bonds connect mol­ecules into chains along [010]

Signal Processing for Digital Beamforming FMCW SAR

According to the limitations of single channel Frequency Modulation Continuous Wave (FMCW) Synthetic Aperture Radar (SAR), Digital Beamforming (DBF) technology is introduced to improve system performance. Combined with multiple receive apertures, DBF FMCW SAR can obtain high resolution in low pulse repetition frequency, which can increase the processing gain and decrease the sampling frequency. The received signal model of DBF FMCW SAR is derived. The continuous antenna motion which is the main characteristic of FMCW SAR received signal is taken into account in the whole signal processing. The detailed imaging diagram of DBF FMCW SAR is given. A reference system is also demonstrated in the paper by comparing with a single channel FMCW SAR. The validity of the presented diagram is demonstrated with a point target simulation results

N-Benzyl-2-(2-chloro-5-methyl­phen­oxy)acetamide

The asymmetric unit of the title compound, C16H16ClNO2, contains two crystallographically independent mol­ecules, which differ mainly in the orientation of the benzyl group with respect to the rest of the mol­ecule. In the crystal packing, centrosymmetrically related mol­ecules are linked into dimers via inter­molecular C—H⋯O hydrogen-bond inter­actions

Competition and cooperation of sulfate reducing bacteria and five other bacteria during oil production

Embargo until March 18, 2023Effective control of sulfate-reducing bacteria (SRB) will help reduce economic losses and prevent threats to human health during the oil production. In this study, the responses of SRB to environmental variables and some functional microorganisms (including denitrifying bacteria (DNB), methanogenic bacteria (MGB), saprophytic bacteria (SPB), zymophyte bacteria (ZPB), and iron bacteria (IB)), during oil production processes were investigated to improve our understanding of how to control SRB abundance. Correlation analyses demonstrated that nitrate and redox potential exihibited significant inhibitory effects on the growth and reproduction of SRB and redox potential (0.175, P < 0.01) had a stronger effect than NO3− (0.0817, P < 0.05). PCA analysis demonstrated a clear division of the bacteria into two clusters, cluster 1 consisted of SRB, SPB and IB, while cluster 2 consisted of DNB, MGB and ZPB. Cooperation was apparent for SRB with SPB and IB, while competition was apparent for SRB with DNB, MGB and ZPB. These results provide new insights to possible solutions to control SRB growth in the oilfield environment, including addition of nitrate and nitrite, to promote the growth of denitrifying bacteria, thereby suppressing the growth of SRB.acceptedVersio

Systematic computational identification of prognostic cytogenetic markers in neuroblastoma

Background: Neuroblastoma (NB) is the most common extracranial solid tumor found in children. The frequent gain/loss of many chromosome bands in tumor cells and absence of mutations found at diagnosis suggests that NB is a copy number-driven cancer. Despite the previous work, a systematic analysis that investigates the relationship between such frequent gain/loss of chromosome bands and patient prognosis has yet to be implemented. Methods: First, we analyzed two NB CNV datasets to select chromosomal bands with a high frequency of gain or loss. Second, we applied a computational approach to infer sample-specific CNVs for each chromosomal band selected in step 1 based on gene expression data. Third, we applied univariate Cox proportional hazards models to examine the association between the resulting inferred copy number values (iCNVs) and patient survival. Finally, we applied multivariate Cox proportional hazards models to select chromosomal bands that remained significantly associated with prognosis after adjusting for critical clinical variables, including age, stage, gender, and MYCN amplification status. Results: Here, we used a computational method to infer the copy number variations (CNVs) of sample-specific chromosome bands from NB patient gene expression profiles. The resulting inferred CNVs (iCNVs) were highly correlated with the experimentally determined CNVs, demonstrating CNVs can be accurately inferred from gene expression profiles. Using this iCNV metric, we identified 58 frequent gain/loss chromosome bands that were significantly associated with patient survival. Furthermore, we found that 7 chromosome bands were still significantly associated with patient survival even when clinical factors, such as MYCN status, were considered. Particularly, we found that the chromosome band chr11p14 has high potential as a novel candidate cytogenetic biomarker for clinical use. Conclusion: Our analysis resulted in a comprehensive list of prognostic chromosome bands supported by strong statistical evidence. In particular, the chr11p14 gain event provided additional prognostic value in addition to well-established clinical factors, including MYCN status, and thereby represents a novel candidate cytogenetic biomarker with high clinical potential. Additionally, this computational framework could be readily extended to other cancer types, such as leukemia

Electronic structure of Fe1.04(Te0.66Se0.34)

We report the electronic structure of the iron-chalcogenide superconductor, Fe1.04(Te0.66Se0.34), obtained with high resolution angle-resolved photoemission spectroscopy and density functional calculations. In photoemission measurements, various photon energies and polarizations are exploited to study the Fermi surface topology and symmetry properties of the bands. The measured band structure and their symmetry characters qualitatively agree with our density function theory calculations of Fe(Te0.66Se0.34), although the band structure is renormalized by about a factor of three. We find that the electronic structures of this iron-chalcogenides and the iron-pnictides have many aspects in common, however, significant differences exist near the Gamma-point. For Fe1.04(Te0.66Se0.34), there are clearly separated three bands with distinct even or odd symmetry that cross the Fermi energy (EF) near the zone center, which contribute to three hole-like Fermi surfaces. Especially, both experiments and calculations show a hole-like elliptical Fermi surface at the zone center. Moreover, no sign of spin density wave was observed in the electronic structure and susceptibility measurements of this compound.Comment: 7 pages, 9 figures. submitted to PRB on November 15, 2009, and accepted on January 6, 201