Femto‐second laser‐based free‐writing of complex protein microstructures and micropatterns, with sub‐micrometer features and controllability over voxel dimension, morphology, and porosity, is reported. Protein voxels including lines, spots, and micropillars are fabricated. Laser power, exposure time, z‐position, protein and photosensitizer concentrations, but not scanning speed, are important controlling parameters. A lateral fabrication resolution of ≈200 nm is demonstrated in 2D line voxels. 3D spot voxels are ellipsoids with 400 nm lateral and 1.5 μm axial dimensions. An ascending z‐stack scanning method to verify the theoretical axial optical resolution, delineate and enhance the axial fabrication resolution of 3D structures, including square prism and cylinder micropillars, is also reported. The micropillar array presents a simple “write‐and‐seed” and table platform for cell niche studies. Fibroblasts attach to, grow on, and express adhesion to molecules on micropillar arrays without the need of matrix coating. They exhibit a more “3D” morphology comparing with that in 2D monolayer cultures and physiological functions such as matrix deposition. This work presents an important milestone in engineering complex protein microstructures and micropatterns with sub‐micrometer topological features to mimic the native matrix niche for cell‐matrix interaction studies.

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The generation of a flexible printed circuit board on polymer fabrics has been a challenge over the last decade. In this work, a copper pattern was obtained on a soft substrate of filter paper/polyacrylonitrile (FP/PAN) film, where the filter paper was commercially available. The pattern of Ag particles was first produced on an Ag+-doped FP/PAN composite film, followed by electroless plating of copper using the metal silver particles as seeds. The in situ reduction of silver particles and the formation of the silver agglomeration pattern were induced by laser irradiation technology on the FP/PAN/AgNO3 composite film. A variety of characterizations indicated that the resultant copper deposition was uniform, with good conductivity properties.

Abstract Antistatic fibers or conductive fibers can be obtained from formation of a metal conductive layer, for example silver, on the surface of polymeric fibers through a redox reaction. However, in the process of fabricating silver-polymer conductive fibers, the binding force between silver and the polymeric fiber matrix is too weak and the poor weather resistance greatly affects the performance of the conductive fibers. This work aims to synthesize composite conductive layers of polyaniline (PANi)-silver coated on polyester fibers to prepare conductive polymeric fibers, in order to improve the combining ability between the conductive layers and the fiber matrix. The morphology, thermostability, mechanical properties, washing resistance and corrosion resistance of the resultant fibers obtained from different synthesis conditions were characterized. Batch experimental results showed that the concentration of the reagent and the reaction time could affect the resistance of the PANi-silver coated conductive fibers. The results also demonstrated that the PANi-silver composite conductive fibers have better properties than those of the silver-polymer conductive fibers.

A chemical factory, using a production technology of acetaldehyde with mercury catalysis, was located southeast of Qingzhen City in Guizhou Province, China. Previous research showed heavy mercury pollution through an extensive downstream area. A current investigation of the mercury distribution in ambient air, soils, and plants suggests that mobile mercury species in soils created elevated mercury concentrations in ambient air and vegetation. Mercury concentrations of up to 600 ng/m3 in air over the contaminated area provided evidence of the mercury transformation to volatile Hg(0). Mercury analysis of soil and plant samples demonstrated that the mercury concentrations in soil with vaporized and plant-absorbable forms were higher in the southern area, which was closer to the factory. Our results suggest that air monitoring using a portable mercury analyzer can be a convenient and useful method for the rapid detection and mapping of mercury pollution in advanced field surveys.

In this work, conductive polyamide fibers were successfully prepared through polymerization of thiophene on the surface of polyamide fibers based on fiber pretreatment and surface activation modification. Sulfuric acid was utilized to roughen the polyamide fibers to increase the activity. Tannic acid (TA) was oxidized and grafted onto the roughened polyamide fibers to convert the inert surface into a highly adhesive tannic acid surface, thus improving the fastness of polythiophene on fiber surface. The effects of treatment temperature, time, and pH were investigated in the preparation process. The surface morphology and chemical structure of the conductive fibers were analyzed by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectrometry (FTIR). The prepared conductive polyamide fibers have robust electrical conductivity, good strength, thermal stability, resilience, washing fastness, sensing properties, and electrothermal properties, providing potential applications in flexible electronic devices, functional sensors, and infrared assisted therapy.

With the rapid development of textile technology, single‐function textile finishing is difficult to meet the current needs of people for textiles. Textiles with flame retardancy, superhydrophobicity, UV resistance, and other functions are increasingly favored by people. At present, most of the preparation processes of multifunctional textiles are complex and time‐consuming. In this work, a flame retardant hexamethylenediamine tetramethylene phosphate ammonium salt of hexamethylenediamine ‐ N, N, N′, N′ ‐ tetra (methylphosphonic acid) (AHDTMPA) was synthesized using hexamethylenediamine tetramethylene phosphate (HDTMPA) and urea with aqueous solution as solvent. Then AHDTMPA and cetyltrimethoxysilane were added into the solution with methyl trimethoxysilane (MTMOS) and tetraethyl orthosilicate (TEOS) as precursors to obtain a multifunctional sol. Finally, the multifunctional cotton fabric can be obtained by immersing the cotton fabric in the multifunctional sol in one‐step. The limiting oxygen index (LOI) and water contact angle (WCA) value of the finished cotton fabric was 27.6% and 131.4°, respectively. The FT‐IR characterization results and the SEM analysis verified the synthesis of AHDTMPA. The micro calorimeter combustion (MCC) and thermo gravimetric (TG) analysis indicated that the finished samples had less heat release capacity and less weight loss. The smoke density test showed good smoke suppression of the finished cotton fabric. Moreover, the whiteness of finished samples was nearly unchanged. In this work, the flame retardant and hydrophobic multi‐functional cotton fabric was prepared by one‐step, and the method is simple and efficient. The prepared functional cotton fabrics can be widely used in home textile fabrics, automotive interior fabrics, clothing fabrics, flags, tents, and protective clothing.