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Glass is a valuable material evidence of the ancient Silk Road between China and the West, but it is easily weathered by environmental factors due to its long history. Weathering causes changes in the internal chemical composition, which affects the correct judgment of the type of glass products. Therefore, the analysis and identification of glass cultural relics become the key problem to be solved. This paper mainly aims at the type and composition of ancient glass, establishes a multi-objective classification model and a multi latitude prediction model, and solves the problem of composition analysis and identification of ancient glass products,first, SPSS was used to fill in the missing values by sequence average method, and the outliers were eliminated by box chart inspection. The partial correlation analysis of glass surface weathering and its type, color and texture is carried out, and the correlation is obtained through the correlation coefficient analysis of glass surface weathering and the three. The statistical law of chemical composition content was obtained by using the data analysis of SPSS software. The content of chemical components before weathering is predicted and determined by the difference between the content of chemical components after weathering and the mean difference before and after weathering.

Toughen effect of the multiblock copolymers (PLA-b-PB-b-PLA)n on PLLA was investigated and the mechanical properties of the blended films were proved to be influenced by the optical isomers of PLA, stereocomplexation and the rubbery PB chains.

Intravenous gadolinium injection (IV-method) can be used to visualize endolymphatic hydrops.This study was designed to use a three-dimensional inversion-recovery sequence with real reconstruction (3 D-real IR) sequence 4 h after the IV-method, images of the perilymph space were scored for endolymphatic hydrops in cases of suspected Meniere's disease (MD) in children to investigate its diagnostic value of MD in children.We collected 28 suspected MD children aged ≤17 years old, all of whom underwent the IV-method. After 4 h, inner ear 3 D-real IR magnetic resonance imaging (MRI) was performed and results were analyzed.Gadolinium contrast agent was seen distributed in the perilymphatic space with perilymphatic enhancement on 3 D-real IR MRI, allowing differentiation between the perilymphatic and endolymphatic spaces. Based on perilymph MRI diagnostic scoring, 64.3% (18/28) of the patients were categorized as having endolymphatic hydrops, who were followed and eventually diagnosed with confirmed MDs.Suspected MD children should undergo gadolinium-enhanced examinations of the inner ear while taking dynamic audiology examinations for the confirmed diagnosis.

Purpose The purpose of this study was to explore the characteristic computed tomography (CT) and magnetic resonance (MR) features of small cell neuroendocrine carcinoma (SNEC) of paranasal sinuses. Materials and methods Computed tomography (n = 8) and MR (n = 14) images and clinical findings from 14 patients with SNEC of paranasal sinuses were retrospectively reviewed. Results Eight lesions were located in the ethmoidal sinus, 4 in the maxillary sinus, and 2 in the sphenoid sinus. Small cell neuroendocrine carcinoma of the sphenoid sinus showed bilateral asymmetry patterns. On CT images, bony changes were visible in all 8 cases. On MR, 4 cases contained hemorrhage, and 10 cases contained cystic or necrotic areas. All cases demonstrated marked heterogeneous enhancement, with half showing a "cribriform-like" or "geographic" appearance. The nasal cavity was the most common site invaded by SNEC of paranasal sinuses, followed by the orbits. A time-signal intensity curve examination showed a washout-type pattern in all but 1 case. The mean ± SD apparent diffusion coefficient value was 0.702 ± 0.112 (×10 mm/s). According to the Dulguerov staging system, 9 tumors were staged as N0 (1 T1, 1 T2, 5 T3, and 2 T4). The recurrence rate was 64.3%. Conclusions Some characteristics of radiological findings can provide important clues for preoperative diagnosis.

A series of UV-curable polyurethanes were made by copolymerization of isocyanate monomers with various diols (PLA1000/PEG2000/HPDMS). The structure of the resulting polyurethanes with DA-generated bonds was characterized by Fourier transform infrared spectroscopy (FTIR) and 1H NMR. In addition, the UV-curing behavior was studied by FTIR. Diels-Alder (DA) and retro-Diels-Alder (r-DA) reactions within cured films was monitored by differential scanning calorimeter (DSC) and dynamic mechanical analysis (DMA), which indicated that the cured film exhibited excellent thermal reversibility over at least three cycles. The resulting PU resins show different healing effect and PLAPU exhibited the most rapid thermal healing with the defect (a scratch with a width of 100 μm) completely healed within 100 s at 120 ˚C. Furthermore, PLAPU has high tensile strength (3MPa) and robust hardness (H) at the same time which is an advantageous feature for applications in which extreme softening or reverse gelation of a self-healing coating would be unacceptable.

Low surface energy coatings have gained considerable attention due to their superior surface hydrophobic properties. However, their abrasion resistance and sustainability of surface hydrophobicity are still not very satisfactory and need to be improved. In this work, a series of utraviolet (UV)-curable fluorosiloxane copolymers were synthesized and used as reactive additives to prepare polyurethane acrylate coatings with low surface energy. The effect of the addition of the fluorinated graft copolymers on the mechanical durability and surface hydrophobicity of the UV-cured hybrid films during the friction-annealing treatment cycles was investigated. The results show that introducing fluorosiloxane additives can greatly enhance surface hydrophobicity of the hybrid film. With addition of 2 wt.% fluorosiloxane copolymers, the water contact angle (WCA) value of the hybrid film was almost tripled compared to that of the pristine PU film, increasing from 58&deg, to 144&deg, The hybrid film also showed enhanced abrasion resistance and could withstand up to about 60 times of friction under a pressure of 20 kPa. The microstructure formed in the annealed film was found to contribute much to achieve better surface hydrophobicity. The polyurethane acrylate/fluorinated siloxane resin hybrid film prepared in this study exhibits excellent potential for applications in the low surface energy field.

Yarn supercapacitors, as knittable and weavable energy storage devices, are attracting more and more attention in recent years. Similar to various yarns with different physical and mechanical properties available in textile industry, different yarn supercapacitors should be developed as well. However, as a device, stretchable yarn supercapacitors suffer a lot from limited stretchability, complicated and high cost fabrication, which greatly restrict their wide adoptions. Here, we use urethane elastic fiber core spun yarns (UY) with intrinsic high stretchability for the first time, as a wearable scaffold for hosting conductive CNT and electrocapacitive PPy to fabricate large-scale highly stretchable yarn electrodes via a simple two-step process (CNTs dipping and PPy electrodeposition). The yarn supercapacitor keeps the excellent stretchability of the UY without using any extra stretchy substrate or wavy structure as most stretchable yarn supercapacitors used, and at the same time, exhibits a high areal capacitance of 69 mF cm −2 (normalized to two electrodes) as well as a good rate capacity. Furthermore, the capacitive performance of the yarn supercapacitor remains nearly unchanged even at a high strain of 80%. The high-performance stretchable yarn supercapacitor with the use of intrinsically stretchable yarns paves a way for the production of large-size fabrics for wearable electronic applications.

Harvesting energy from environment (e.g. human motions), is a cost-effective strategy to power the personal electronics. Triboelectric nanogenerators (TENGs) have been proven to be an effective device that can scavenge the biomechanical energy from human motions. However, the compatibility for wearing and mechanized production, two critical criterions for practical applications, of the TENGs remain as challenges. Here, we demonstrated an elegantly designed 3D knitted spacer fabric based TENG by utilizing the vertical contact electrification between two polymers with different tribo-polarities. The open circuit voltage of the one single TENG pixel of as-fabricated TENG reaches more than 3 V, while the short circuit current reaches around 0.3 μA. The output power reaches 16 μW, whereas it can be delicately tuned by controlling the number of TENG pixels involved. As a power source, the as-fabricated TENG can continuously lit up the LEDs. In addition, the as-fabricated TENG shows outstanding ability to effectively monitor the human motions. Furthermore, the ability of in situ sensing the pressure of a foot during the human walking was successfully realized. Our study reports a novel large-scale-fabrication method of TENGs compatible with mechanized production, which shows outstanding output performance as well as the excellent smart sensing abilities.

Poisson’s ratio (PR) is defined as the negative ratio between the lateral strain and the longitudinal strain of a material under tensile or compressive loading condition. Auxetic fabrics are those having a negative PR, which means that when their longitudinal strain is positive, their lateral strain is also positive, and vice versa. In this work, tensile and forming properties of auxetic warp-knitted spacer fabrics were investigated and compared with those of the conventional warp-knitted spacer fabrics. Both uniaxial tensile tests and hemispherical compression experiments were conducted, and the relationships of the tensile and forming properties with the auxetic effect were discussed in terms of different fabric structural parameters. The results show that the auxetic warp-knitted spacer fabrics have a prolonged low stress stage in the wale direction, indicating that they are more prone to undergo deformation along the wale direction, and fabric with a longer low stress stage has a better auxetic effect. The results also show that the formability of auxetic warp-knitted spacer fabrics is much better than that of conventional warp-knitted spacer fabrics, due to the much low forming energies required under hemispherical compression, which can be affected by many factors such as auxetic effect, fabric thickness and stiffness, yarn materials and the structure of the spacer layer. When all other parameters are similar, auxetic fabric with a better auxetic effect will have better formability. The study has provided useful information for the design and application of this type of nonconventional spacer fabrics.

Great progress has been made in the research of self-healing materials in recent decades, however, there are still great challenges in achieving high mechanical strength and wide scratch healing simultaneously. Herein, a novel polyurethane elastomer (PUDA) containing polycaprolactone (PCL) soft segments and Diels-Alder (DA) adducting structure was specially designed and synthesized. The experimental results show that the PUDA elastomer after being trained not only had ultrahigh mechanical strength, but also had satisfactory ability in healing of wide scratches. It was found that the elastomer displayed a high tensile strength up to 32.88 MPa, which is unprecedented when compared to those reported self-healing elastomers. The PUDA elastomer material also had excellent healing ability towards wide scratches: an 80-μm-wide scratch could be completely healed after heating at 110°C for 6 min. Furthermore, the elastomer material could also attain more than 100 % recovery of mechanical strength, with its recovered tensile strength reaching up to 34.58 MPa. The developed PUDA elastomer demonstrates quite promising perspective in material science and engineering field, especially for the protection of surface coating.

Self-healing is a very hot topic in hydrogel community since its close relationship with broad applications such as injectable hydrogels for cell delivery, bioinks for 3D printing, and drug delivery carriers. Considerable efforts have been devoted to fabricate hydrogels with superior self-healing ability and moderate mechanical property. But more of the reported self-healing hydrogels do not own fast self-healing behavior and high mechanical strength at the same time. Herein we report a tough hybrid hydrogel which can realize ultra-fast self-healing process. This hydrogel was prepared based on polyvinyl alcohol (PVA), borax and poly-dopamine particles (PDAPs). With the incorporation of PDAPs particles, the hybrid hydrogels exhibited higher mechanical strength and faster self-healing property than PVA-borax hydrid hydrogel only. Benefited from the rapid self-healing performance, enhanced mechanical properties, good biocompatibility and simple preparation method, this novel hybrid hydrogel is expected to have great potentials in widespread applications such as electrical skin, tissue engineering, drug delivery, 3D printing and soft robots.

Low surface energy materials have attracted much attention due to their properties and various applications. In this work, we synthesized and characterized a series of ultraviolet (UV)-curable fluorinated siloxane polymers with various fluorinated acrylates&mdash, hexafluorobutyl acrylate, dodecafluoroheptyl acrylate, and trifluorooctyl methacrylate&mdash, grafted onto a hydrogen-containing poly(dimethylsiloxane) backbone. The structures of the fluorinated siloxane polymers were measured and confirmed by proton nuclear magnetic resonance and Fourier transform infrared spectroscopy. Then the polymers were used as surface modifiers of UV-curable commercial polyurethane (DR-U356) at different concentrations (1, 2, 3, 4, 5, and 10 wt %). Among three formulations of these fluorinated siloxane polymers modified with DR-U356, hydrophobic states (91&deg, 92&deg, and 98&deg, ) were obtained at low concentrations (1 wt %). The DR-U356 resin is only in the hydrophilic state at 59.41&deg, The fluorine and siloxane element contents were investigated by X-ray photoelectron spectroscopy and the results indicated that the fluorinated and siloxane elements were liable to migrate to the surface of resins. The results of the friction recovering assays showed that the recorded contact angles of the series of fluorinated siloxane resins were higher than the original values after the friction-annealing progressing.

This paper reports the tensile deformation behavior of an auxetic warp-knitted spacer fabric structure by using the finite element (FE) method. The precise geometry of the outer layer structure of the fabric was firstly obtained from a micro X-ray computerized tomography scan and then inputted to an ANSYS 13.0 software to generate geometrical models. The geometrical models were then meshed using the PLANE 183 element to build FE models. Based on the FE models built, deformation behaviors of the auxetic fabric in the course direction and wale direction were simulated and compared with experimental results. The FE analysis showed that the simulated fabric deformations at different tensile strains were very close to the real fabric deformations and the FE-generated Poisson’s ratio-strain curves agreed well with the experimental ones. Therefore, the FE models could be used for predicting the deformation behaviors of the auxetic warp-knitted spacer fabric stretched in different fabric plane directions.

Auxetic materials are a kind of non-conventional materials having negative Poisson’s ratio. They laterally expand when stretched or laterally shrink when compressed. Compared to conventional materials, auxetic materials have a number of enhanced properties that could be very interesting for some special applications. This paper reviews the latest achievements in auxetic materials, including their properties, structures and applications. A special discussion on their potential applications in textiles is also made. It is expected that this review could provide some useful information for the future development of auxetic textile materials.

Auxetic spacer fabrics are a novel kind of three-dimensional (3D) fabric structure with a negative Poisson’s ratio. They have found a number of applications in functional garments, protective pads and sportive shoes due to their unusual properties. In this paper, a study on deformation behaviors of 3D spacer fabrics that could be fabricated on a large scale is reported. Through experimental observations of deformation of a basic hexagonal unit at different tensile strains, two different geometrical models are proposed for the fabric structure when extended in the course direction and wale direction, respectively. Based on the geometrical models, two semi-empirical equations between the Poisson’s ratio and tensile strain are established for both tensile directions. The study shows that the established semi-empirical equations fit well with experimental results. Therefore, they could be used in the design and prediction of 3D auxetic spacer fabrics with different values of geometrical parameters.

Endowing UV-curable coatings with self-healing properties by incorporating dynamic bonds into their cross-linking network is of vital significance. However, in practical applications, self-healing polymers are often plagued with problems such as a high healing temperature and long healing time. To address this challenge, we developed a new type of UV-curable polyurethane coating by the combination of Diels-Alder and thiol-ene click reactions. The Diels-Alder bonds in the polyurethane samples developed in this work furnished perfect mechanical properties and self-healing ability. Self-healing of polyurethane based on Diels-Alder bonds usually occurs at 120 °C. Thiol-ene click reaction is a robust, novel polymerization method, and it improved the structural performance of the polymer with a more homogenous structure being formed than that achieved with traditional UV-curing. Herein, a novel UV-curable self-healing coating, which is referred to as a PU-SH system, was designed by integrating thiol-ene into polyurethane resins containing Diels-Alder bonds. Results of analyses by assorted techniques (including Fourier-transform infrared spectroscopy, different scanning calorimetry, rheology, optical microscopy, and 3D optical interferometric profilometry) strongly indicated that the self-healing ability of the prepared coatings is superior to those of previously studied traditional UV-curing coatings, which are referred to as PU systems. The resultant coatings of the PU-SH system showed a remarkable reduction in the healing temperature from 120 °C for the PU system to 90 ˚C. The rapid scratch-healing properties of the UV-curable coatings, taken together with the moderate healing temperature makes the material attractive for a variety of applications, such as in flexible electronic screens, car paint film, and aircraft interior finishes.

Auxetic fabrics have gained an increasing attention in the auxetic material area in recent years. Especially, auxetic fabrics fabricated based on both weft-knitted and warp-knitted structures have made some important progress. However, all the knitted auxetic fabrics reported so far are fabricated based on 2D knitted structures, although some of the weft-knitted auxetic fabrics are finally formed into 3D forms. This paper reports a novel kind of 3D auxetic fabric fabricated based on a warp-knitted spacer structure with adoption of a special geometrical configuration which is formed with parallelograms. The auxetic behavior of these fabrics is discussed in terms of tensile direction, geometrical parameter, and repeated extension. The shape fitting ability on a spherical surface is also demonstrated. The results shows that the 3D auxetic fabrics have auxetic behavior in all the fabric plane directions and the highest auxetic effect is obtained when stretched in the weft direction of the fabric. The 3D auxetic fabrics also display an excellent shape fitting ability, which makes them very attractive for various applications where fitting to the human body's shape is highly required, such as bra cups, protectors for knees and elbows, shoes covers, etc.

Flat knitting is a widely used fabric manufacturing technology. Compared with warp knitting and circular knitting, flat knitting is characterized by its higher process flexibility and greater fabric structure variety. In this work, flat knitting technology was exploited to fabricate auxetic fabrics which laterally expand when stretched. Three kinds of geometrical structures, i.e. foldable structure, rotating rectangle and reentrant hexagon, were employed as basic reference structures for the development of these kinds of auxetic fabrics. The weft knitting processes based on these structures were specially developed and auxetic fabrics were fabricated using the computerized flat knitting machines. The Poisson’s ratio-strain curves of the developed fabrics were plotted and compared with those calculated using existing models to demonstrate the variation trends of Poisson’s ratio with the axial strain. The results reveal that except the folded fabric formed with the face loops and reverse loops in a rectangular arrangement, of which the auxetic effect firstly increases and then decreases with the axial strain, the auxetic effects of all other fabrics decrease with an increase of the axial strain. The work also shows that auxetic fabrics can be realized based on knitted structures and that flat knitting technology can provide a simple, but highly effective way of fabricating auxetic fabrics from conventional yarns.

A mathematical simulation of the perception of thermal and moisture sensations is developed using mathematical models that describe the physical mechanisms of heat and moisture transfer in fabrics, the neurophysiological responses of thermoreceptors. and the psychoneurophysiological relationships identified from experiments. The sensations of coolness and dampness to the touch of knitted fabrics are predicted and compared with the subjective perceptions measured in a psychological experiment. The experimental results show that, in general, the relationships between the neurophysiological responses of thermoreceptors and the psychological perceptions follow Stevens' power function. The good agreement found between the measured and simulated perceptions shows that this mathematical simulation, based on heat and moisture transfer in fabrics, neurophysiolog ical mechanisms of the thermoreceptors, psychophysical relationships, is able to predict the perception of coolness and dampness sensation to the touch with reasonable accuracy.

In this work, polyacrylonitrile (PAN)-based carbon fibers (CF) were chemically modified with poly (glycidyl methacrylate) (PGMA) via atom transfer radical polymerization (ATRP) to improve the interaction between the CF and polymer matrix. The FT-IR, TGA, and XPS were used to determine the chemical structure of the resulting products and the quantities of PGMA chains grafted from the CF surface. The experimental results confirm that the CF surface was functionalized and glycidyl methacrylate was graft-polymerized onto the CF, and the grafting content of polymer could reach 10.2%.

This paper investigates the influence of waterproof fabrics on heat and moisture transfer through a clothing system. The water vapor permeability (WVP) for the outside layer was derived from published experimental data, and was considered to be a factor influencing the mass transfer coefficient at the boundary exposed to the environment. The analysis was carried out by using a mathematical model that describes the coupled heat and moisture transfer in porous textiles. The numerical simulation reveals a significant influence of water proof fabrics on the dynamic moisture content distribution in fabrics⁄fibers, moisture vapor condensations and the liquid transfer behavior inside the clothing. The research has shown the potential usage of the mathematical simulation in evaluating the performance of different waterproof and breathable fabrics in clothing systems, as well as the potential usage in the product development of functional apparel.