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Due to the damage of scalp because of chemical dyes, increasing attention had been paid to the ecological dyeing of human hair. To address the need for ecological restoration and dyeing of human hair, herein, a novel approach has been proposed via laccase-mediated in situ oxidation of dihydroxy phenylalanine (dopamine). As laccase can catalyze dopamine oxidation and then polymerization to produce strongly colored polymers, different biological coloration processes of human hair based on this process were investigated: (i) Human hair was treated with laccase alone; (ii) The absorption of human hair with dopamine, followed by further catalysis of air; (iii) The absorption of human hair with dopamine, followed by further catalysis of laccase; (iv) Simultaneous laccase-mediated polymerization and dyeing of human hair; and (v) Polymerization of Dopamine with laccase and then dyeing human hair. The surface properties of dyed hair were evaluated in terms of ultraviolet (UV)-protection, color fastness, Fourier transforming infrared spectrum (FT-IR), optical microscope, and scanning electron microscopy (SEM). The results show that best hair dyeing effect was achieved via simultaneous laccase-mediated polymerization and dyeing. The dyed hair obtained K/S values of 28, light fastness of level 5, and UPF of 100+. The optical microscope and SEM observations show that the surface of colored hair fibers was covered with thin burrs, which can be attributed to polydopamine attached with physical adhesive force and covalent reaction. FT-IR analysis shows that functional groups were present on the surface of the dyed hair which can be considered as introduction of hydroxyl radical groups. This biological stain technique may be widely used in dyeing of hair with black color.

In order to investigate the relationship between breaking stress and whiteness in a bleaching treatment with laccase, hair samples from three biogeographically distinct populations were characterized by various chemical and physical techniques. Factors affecting whiteness and breaking stress were investigated by attenuated total reflection infrared spectroscopy, atomic absorption spectroscopy, X-ray diffraction and scanning electron microscopy. The results reveal that whiteness and breaking stress after bleaching are primarily influenced by the diversity of concentration of metal ions and functional groups in the hair. The hair samples with lower content of metal ions obtain better whiteness and higher stress retention. The presence of OH functional group increases the final whiteness of the hair sample, while lack of that not only decreases the whiteness but also leads to more stress loss. In addition, the presence of the C-C functional group also decreases the whiteness.

Microseismic monitoring is an important technology used to evaluate hydraulic fracturing, and denoising is a crucial processing step. Analyses of the characteristics of acquired three-component microseismic data have indicated that the vertical component has a higher signal-to-noise ratio (SNR) than the two horizontal components. Therefore, we propose a new denoising method for three-component microseismic data using re-constrain variational mode decomposition (VMD). In this method, it is assumed that there is a linear relationship between the modes with the same center frequency among the VMD results of the three-component data. Then, the decomposition result of the vertical component is used as a constraint to the whole denoising effect of the three-component data. On the basis of VMD, we add a constraint condition to form the re-constrain VMD, and deduce the corresponding solution process. According to the synthesis data analysis, the proposed method can not only improve the SNR level of three-component records, it also improves the accuracy of polarization analysis. The proposed method also achieved a satisfactory effect for field data.

A new polyoxoniobate constructed by four {Nb27} building blocks, K11[Cu(en)2(H2O)2]2[H29{Cu(en)2}4{Cu0.5(en)2}4{Cu(en)2(H2O)}4(OH)4(Nb27O75)4]·103H2O (en = ethanediamine), has been synthesized and characterized. Four {Nb27} inorganic blocks are linked by metal-organic components [Cu(en)2]2+, forming a tetrameric organic–inorganic hybrid. The structure is characterized by IR spectroscopy, XRD, UV–vis, EPR, single crystal X-ray diffraction, thermal gravimetric analysis and elemental analysis. Furthermore, the solution behavior was investigated indicating the integrity of {Nb27} building block, which shows the possibility that it might be an excellent precursor for functionalization.

Thermal conductivity measurement; Evaporation efficiency calculation; Application photo; Water contact angles; The evaporation efficiencies; Comparison of materials in references; TGA of cotton fabric and RGO/cotton fabric.

Two new capping Nb-Keggin clusters, [{Cu(2,2′-bipy)}6(TNb12O40)]3− (T = P and As), have been hydrothermally synthesized and characterized by IR spectroscopy, single crystal X-ray diffraction, powder X-ray diffraction, elemental analysis and thermal gravimetric analysis. The polyoxoanion [{Cu(2,2′-bipy)}6(TNb12O40)]3− consists of a classical α-Keggin-type {TNb12O40} structure capped by six {Cu(2,2′-bipy)} fragments, which represents the first example of copper-capped Keggin-type {TNb12O40} polyoxoanion. Besides, the organo-amines play key roles in the construction of structural diversity under the studied system.

The hydrothermal reaction of Lindqvist [Nb6O19]8−, sodium pyrophosphate with transition metal ion (CoII) in the presence of amine results in one novel transition-metal-linked trivacant Keggin heteropolyniobate: K6Na17[H3{Co(H2O)3}2(P4Nb9O40)2]·24H2O. The compound has been structurally characterized by EDS, IR spectra, XPS, thermogravimatric analysis, and X-ray crystallography. The solid-state structure is composed of two {P4Nb9} fragments linked by [Co(H2O)6]2+ ions, further leading to the formation of 2D sheet-like architecture. Interestingly, the Nb-oxo cluster achieves transformation in situ.