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HNBR/FKM composites were prepared by compounding carbon black (CB), hydroxide zinc monomethacrylate (HZMMA) and carbon nanotubes (CNTs) to modify hydrogenated nitrile rubber (HNBR)/ fluororubber (FKM) blend, and the effects of the composite reinforcing agent on the curing characteristics of HNBR/FKM blends, and the physico-mechanical properties, dynamic mechanical properties and thermal-oxydative aging properties of the vulcanized rubber were investigated. The results showed that the curing rate of HNBR/FKM compo-sites was accelerated and the cross-linking degree was increased when HZMMA and CNTs were added, and the physico-mechanical properties of HNBR/FKM composites were significantly improved under the synergistic effect of HZMMA and CNTs. HNBR/FKM composites reinforced by HZMMA and CNTs of 3 phr (mass) exhibited the highest retention rate of elongation at break and the lowest change rate of hardness after thermal-oxydative aging compared with that reinforced by pure CB. As the addition amount of CNTs increased, the glass transition temperature of HNBR/FKM composites moved towards the lower temperature and the loss factor decreased gradually.

The effect of different Ti contents on the microstructures and tensile mechanical properties of the hot-extruded Cu-15Ni-8Sn alloys was investigated by optical microscopy, scanning electron microscopy, transmission electron microscopy and tensile test. The results show that both ultimate tensile strength and yield strength increase significantly with the increase of Ti content, while elongation decreases. The addition of 0.02% (mass fraction, the same below) Ti facilitates the precipitation of γ-(Cu, Ni)3Sn phase, and thereby leads to a significant refinement of recrystallization grain. When the content of Ti increases to 0.3%, a small quantity of needle-like Ni3Ti phase is formed, which abates the effect of γ precipitates on inhibition of recrystallized grains growth. With the addition of up to 0.5% Ti, a larger amount of Ni3Ti precipitates are formed, which enhance the effect of recrystallized grain refinement; however, a few Ni3Ti precipitates become large and deteriorate the elongation of the alloy. In this study when 0.3% Ti is added, the mechanical properties of the alloy are preferable, where the tensile strength, yield strength and elongation are 875, 713MPa and 24.1% respectively.

This document is a correction notice for an article titled "Melatonin Alleviates High Temperature-Induced Pollen Abortion in Solanum lycopersicum" published in the journal Molecules. The correction addresses a mistake in Figure 2A of the original publication, where an image was overwritten by a redundant image. The corrected figure is provided, and the authors state that this correction does not affect the scientific conclusions of the study. The original publication has been updated accordingly. [Extracted from the article]

This study examines the imaging problems in airborne synthetic aperture ladar with single detector and dual detectors along tracks under platform vibration condition. Because platform vibrations affect imaging processing for short intervals negligibly, a method uniting the subaperture imaging and phase gradient autofocus is considered for single-detector ladar. To obtain long stripmap images in azimuth, the stripmap phase gradient autofocus method and the subaperture image mosaic process using Doppler centroid estimation are used. Their performance is analyzed and compared. Considering the shortage of single-detector ladar, a method based on along-track dual-detector interferometric processing is proposed to estimate and compensate for the vibration phase error. The simulation verifies the effectiveness of the proposed methods.

In this study, the performance of three phase-modulated signals used in airborne Synthetic Aperture Ladar (SAL) is investigated. The transmitting and receiving modes and imaging processing methods for these signals are studied. Considering that the swath of the airborne SAL is very narrow, in order to reduce the AD sampling rate of the wideband signal, a “phase-dechirping” receiving mode is proposed for the phase-modulated signal based on the Linear Frequency Modulation (LFM) signal. The imaging simulation results for these three phase-modulated signals validate the effectiveness of the proposed method.

In this study, the concept and system of a distributed POS are discussed. Based on the different operation modes, the principle technical parameters and requirements for optical camera and imaging radar with multiple subarray antennas are presented. Further, technical approaches to obtain precise position and attitude information for the POS are investigated, and some possible applications are proposed.

The current status and the domestic research problems of air-borne Synthetic Aperture Ladar (SAL) are introduced and key technologies are analyzed. Based on a principle prototype, the system implementation scheme with a combination of SAR electronics technology and optical technology is given. The future practical system metrics and technological approaches are analyzed. Besides, application direction of Synthetic Aperture Ladar is clarified.

In this paper, modeling of the channel leakage error of a three-baseline MMWInSAR (MilliMeter Wave Interferometric Synthetic Aperture Radar) is analyzed, and the mathematical expression of the error’s parameters and interference phase error is deduced. Furthermore, using quantitative analysis, the paper investigates the impact on the interferometric phase error and elevation error from the channel leakage. Finally, a compensation method for the channel leakage error is presented. The results of simulation experiments verified the effectiveness of the compensation method.