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With the development of nano molding technology (NMT), the polymer/metal hybrid (PMH) composites have made great progress in industries like automobile, aircraft, and boat. The bonding structure and bonding strength are the key factors ruling the application of PMH. In this work, the PMH containing polyphenylene sulfide (PPS) and Al alloy was prepared by NMT, and the surface treating of Al alloy and the bonding mechanism of PMH has been studied. The results reveal that the bonding strength between metal and polymer shows dependence on the pore structure of the metal surface, which could be controlled by changing the anodizing voltage and time. The PMH in which the Al plate was anodized at 15 V for 6 h achieves the best bonding strength of 1,543 N. The morphological analysis reveals that there forms an anchor and bolt structure in the interface of PPS and Al plate, which bonds the polymer and metal tightly. In addition, the chemical interaction between PPS and Al was confirmed by attenuated total reflection (ATR) infrared spectroscopy, which indicates that both physical and chemical effects contribute to the bonding strength of the PMH. This PMH has great potential of being used as alternative to traditional pure metal components, especially the packing materials of automobiles, electronic products, and furniture.

Cordierite is a violet-blue gem mineral primarily composed of magnesium aluminum silicate. This study employed three samples of Mg-cordierite and conducted tests on their gemological characteristics, spectroscopic features, and chemical composition using Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, ultraviolet spectrophotometry, X-ray photoelectron spectroscopy (XPS), and electron microprobe. The study also explored and analyzed the polychroism and coloration mechanisms of the samples. The results indicate that the lattice vibrations of the Mg-cordierite samples differ along the directions parallel to the a, b, and c crystallographic axes, leading to certain variations in spectral characteristics among these directions. The article provides experimental evidence for the reasons for the polychroism of cordierite in different crystal axes, which is of great significance in the quality evaluation of cordierite. [ABSTRACT FROM AUTHOR]

Because of the rich fluorescent color and unique photochromic properties, hackmanite has attracted many mineralogists. In this paper, the basic gemmological characteristics and photochromic and fluorescence mechanisms of four different colors of hackmanite are further investigated through the study of their structural, compositional, and spectroscopic features. The results show the change in the color of hackmanite in photochromism is caused by the joint action of the F-center and the oxygen hole centers. The change in the UV-Vis spectra may be caused by the superposition of two peaks. Under 365 nm UV excitation, the peak of fluorescence spectra of 662 nm is related to the 2∏g→2∏u transition of S2−, the blue emission at 441 nm is caused by the 3P0.1→1S0 transition of s2 ions (Pb2+, Tl+, Sn2+ Sb2+), and at 541 nm is caused by the Mn2+ center. The results are helpful in deepening the understanding of photochromism, fluorescence mechanism, and its structure, expanding the application of hackmanite. [ABSTRACT FROM AUTHOR]

The application of time domain index and kurtosis analysis method in the fault diagnosis of rolling bearing is studied. Firstly,the kurtosis values of each signals are obtained by equi- spaced and different frequency band- pass filter of bearing signals. Secondly,through the maximum principle of kurtosis value,the frequency band of the fault diagnosis is determined,and then the frequency range is determined as the filter parameters. Finally,by calculating the time domain index of filter to diagnose the rolling bearing. The test results show that the frequency band range obtained through this way is reasonable,which will also improve the rate of diagnosis accuracy.

Agate attracts the attention of gem mineralogists because of its variable colors. The color of agate is closely related to its naming and classification, so it is necessary to study the color and mineral origin of agate. In this paper, the mineralogical characteristics and color origin of red, yellow and green Moqi agates from Inner Mongolia were systematically studied by means of Fourier transform infrared spectrometer, Raman spectrometer, X-ray powder diffractometer, electron probe microanalyzer and ultraviolet–visible spectrophotometer. It is found that the color of Moqi agate is related to the minerals and trace elements contained in it, and is associated with the electron transition or charge transfer of Fe ions in the contained minerals. Green agate has the highest Fe content, and its color is caused by celadonite inclusions. The red and yellow color in Moqi agate is mainly caused by hematite and goethite, while red agate contains more Fe than yellow agate. Raman spectroscopy and X-ray diffraction analysis show that the content of moganite in Moqi agate is 0–30%. It is calculated that the crystallinity of Moqi agate is 1.5–3.5. This work provides a theoretical basis for future research on the identification of Moqi agate. [ABSTRACT FROM AUTHOR]

Spinel is a common gemstone that has attracted the attention of gemologists worldwide because of its high refractive index, rich colors and brilliant hues. Myanmar is an important source of spinel. The present paper provides a systematic characterization of the gemological features of different color spinels from Myanmar, with a discussion and analysis of their color causes. The results show that complete octahedral crystal forms can be seen in Myanmar spinel, with the appearance of dissolution, growth motifs and cross-growth of crystals visible on the crystal surfaces. The XRF results show that the Myanmar red and orange spinel samples contain high levels of Cr, with the magenta sample having significant levels of Cr and the orange sample having more V. The blue and purple samples have high levels of Fe. The peaks of the infrared spectrum mainly appear around 841 cm−1, 690 cm−1 and 532 cm−1. Raman spectra have peaks mainly around 310 cm−1, 405 cm−1, 663 cm−1 and 764 cm−1. According to the UV-Vis spectrum, the color of Myanmar red and orange spinels is mainly due to Cr3+ and V3+. When the Cr3+ content is higher than the V3+ content, the spinels show a red hue; when the V3+ content is higher than Cr3+, the spinels have an orange hue. Blue color is due to the charge transfer between Fe2+ and Fe3+. The research in this paper has enriched the gemological characteristics of Myanmar spinel and can provide a theoretical basis for its investigation, marketability, design and utilization. [ABSTRACT FROM AUTHOR]