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Keywords: Pomelo peel; extraction; cellulose nanofibrils; lemon juice hydrolysis; ; ; ; ; EN Pomelo peel extraction cellulose nanofibrils lemon juice hydrolysis ZH 8415 8428 14 11/21/22 20221220 NES 221220 Introduction The large-scale production of the agricultural products in the recent decades has brought significant economic benefits to the humanity; however, the negative impact of the agricultural residues on the environment cannot be ignored (Ullah, Kumar Sharma, and Dhingra et al. [45]). It was observed that with the gradual processing stages, the impurities such as hemicellulose and lignin were removed, and the relatively pure cellulose material with the chemical structure of natural cellulose was obtained. However, in this study, these peaks are observed to be separated after ball milling, which shows that the high-energy ball milling is able to effectively peel off hemicellulose and lignin around cellulose to further purify the extracted cellulose. This is owing to the effective removal of ash, grease, and non-cellulose entities on the surface of cellulose during the extraction process, thus, exposing the cellulose material inside the raw sample. [Extracted from the article]

Abstract: A new consolidation system for fragile ancient silk fabrics by fibroin with the support of ethylene glycol diglycidyl ether (EGDE) was developed in our group. To figure out the mechanism and the effect of EGDE in the system, aged silk fabrics treated with EGDE have been investigated in this paper. Silk fabrics were artificially aged in sodium hydroxide aqueous solution to simulate fragile ancient silk fabrics. The aged silk fabrics were treated with EGDE aqueous solution by spraying. The resultant silk fabrics were systematically investigated by tensile test, thermogravimetric analysis (TGA), thermal ageing resistance test, attenuated total reflection Fourier transform infrared spectroscopy (ATR–FTIR), solid-state 13C cross polarization/magic angle spinning nuclear magnet resonance (13C CP/MAS NMR) and amino acid analysis (AAA), etc. Results indicate that the breaking stress and strain of the treated silk fabrics increase more than four and two times, respectively. The maximum decomposition temperature of the treated silk fabrics is much higher than that of the aged silk fabrics. The treated silk fabrics exhibit a better thermal ageing resistance than the aged silk fabrics. Chemical interactions occurred between EGDE and silk fibroin molecules in silk fabrics. This work provides useful information for the protection of historic silk fabrics. [Copyright &y& Elsevier]

Abstract: A novel intelligent humidity control composite material with excellent humidity control performances has been prepared, comprising a natural polymer derivative (carboxymethyl cellulose (CMC)), a porous natural mineral (sepiolite), and an acrylic acid (AA)/acrylamide (AM) copolymer. It features high moisture adsorption capacity, fast response to humidity changes, small equilibrium humidity control range and good acid gas absorbability. It is suitable for maintaining a proper micro-environment for places such as museums or galleries. The appearance and structural properties of the resultant material have been investigated by scanning electronic microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The humidity control performances of the material at certain relative humidity (RH) and changed absolute humidity (AH) have been measured. The adsorption capabilities of the material for sulphur dioxide and nitrogen dioxide have also been investigated in this study. The results reveal that the material maintains a relative humidity in the 57–60.5% range at 25°C, and reaches the equilibrium levels within 3.5h. It is worth noting that the composite material shows an excellent humidity buffering effect at changed AH and temperatures. The equilibrium moisture adsorption amount is 78.6% of its own weight. The adsorption capacities for nitrogen dioxide and sulphur dioxide are 227mgg−1 and 288mgg−1, respectively. [ABSTRACT FROM AUTHOR]

Abstract: A new type of stimuli-responsive organic/inorganic nano-composite hydrogel was prepared by introducing fibrillar attapulgite into poly(2-hydroxyethyl methacrylate-co-poly(ethylene glycol) methyl ether methacrylate-co-methacrylic acid) network, in which the nanosized attapulgite fibril worked as the cross-linker instead of conventional chemical cross-linker. In the preparation process, a prepolymerization route was adopted to effectively stabilize the dispersion of attapulgite. The structure and morphology of the nano-composite hydrogels were characterized by SEM, FTIR and DSC. The swelling/deswelling behaviors and tensile mechanical properties of the nano-composite hydrogels were compared with that of the corresponding chemically cross-linked hydrogel. The results showed that the nano-composite hydrogels had much greater equilibrium-swelling ratio, much faster response rate to pH and significantly improved tensile mechanical properties. As the content of AT increased, the tensile strength, effective cross-link chain density and glass transition temperature increased, while the equilibrium swelling ratio, deswelling rate and elongation at break decreased. [Copyright &y& Elsevier]

Mineral pigments have an important position in the traditional arts. To better protect cultural relics, the effects of high energy ball milling on the structure and properties of mineral pigments was investigated using malachite and turquoise as examples. Samples were characterized using a range of physical and spectroscopic measurements to determine the composition, morphology, and particle size of the samples. Chromaticity analysis was carried out using the L*a*b* color space model. The results showed that milling reduced the size and distribution of the mineral particles, reaching an amorphous state of high specific surface area. The crystalline state of the samples changed with milling time. Valency, atomic abundance, luminance, reflectivity, and chromaticity of the milled samples all showed various changes affected by crystallinity and grain size. Color change in malachite manifested mainly as a red-shift yellowish green with increasing milling time. Polycrystalline turquoise was bluish green and showed no color change during milling. The results from this study may provide the basis for improvements in antique pigment technology and assist with the selection of suitable pigments for the restoration of paintings. • Two natural greenish mineral pigments were treated with high energy ball milling. • The crystal form of part mineral pigments has changed after mechanochemical routes. • Mineral pigment color differences can be obtained by ball milling. • A method for precise colorimetric measurement of pigment powders. [ABSTRACT FROM AUTHOR]

The mineralization mechanism responsible for the fossilization of archaeological textiles in close proximity to metal artifacts presents a sophisticated preservation process at both macro and micro levels. This study examines archaeological textiles dating from 2200 BC to AD 1900, sourced from three distinct archaeological sites. The focus is on understanding the microstructural degradation of fibers within a specific burial environment and the preservation achieved through mineralization. These archaeological fibers of archaeological textiles exhibit morphological preservation in the immediate vicinity of copper-based objects. Utilizing tools such as a digital camera, scanning electron microscopy with energy dispersive spectroscopy (SEM–EDS), high-resolution synchrotron-based microtomography (μCT), and enzyme-linked immunosorbent assay (ELISA), we examined fiber morphology, conducted elemental analysis, identified fiber types, and analyzed fiber characteristics. Our findings reveal the presence of smooth-surfaced wools and silks, fibers covered with calculi, and fiber impressions—all subjected to mineralization. These mineralized fibers can be categorized into three distinct stages of mineralization, each exhibiting varying carbon content. We inferred a correlation between mineralization rate and carbon content while also identifying mineralization density distribution on these textiles. Lastly, this study provides insights into the preservation states of textiles across three different mineralization stages, enriching our understanding of the deterioration of organic archaeological material. [ABSTRACT FROM AUTHOR]

This work studied the concretion components of ancient silk fabrics unearthed from Nanjing, China. Based on the analysis of the components, mechanism of concretion of the silk fabrics were proposed. Physical, chemical, and biological factors were considered as possible reasons for the concretion of ancient silk fabrics. Mechanical extrusion or falling, crystal bonding, Van der walls forces, hydrogen bonding, covalent bonding, and ionic bonding are purposed as possible influences and/or interactions between the concretion components and silk fabrics. The concretion mechanism, which includes common mineralization nucleation, re-crystallization, bio-mineralization nucleation and crystallization are discussed separately. Mineralization nucleation and crystallization have a great influence on the aging, hardening (even rotting), and final concreting of buried silk fabrics. Possible processing models were established according to the results obtained. This study presents new viewpoints to understand the concretion of unearthed silk fabrics, which could provide theoretical evidence for the unfolding of concreted silk fabrics, especially those fragile, even rotten ones. [ABSTRACT FROM AUTHOR]

Here we report a high‐efficiency visible‐light responsive tube‐sheet nanocomposite (Zn‐TCPP NS/TNTs) fabricated by an improved hydrothermal method. The characterization results give deep insights into the structures and interaction between the TNTs and Zn‐TCPP NS. The composites consisting of 5% Zn‐TCPP NS show a marvelous photocatalytic performance for the initial high concentration MB solution (30 mg/l) under visible light, which was about 2 times more than that of the pure TNTs. The electrochemical impedance spectroscopy of the 5% Zn‐TCPP NS/TNTs composites are obviously lower than that of the 1% Zn‐TCPP NS/TNTs composites and pure TNTs, and the photocurrent of the 5% Zn‐TCPP NS/TNTs composites is 3.8 times than the pure TNTs. The reason is that,on one hand, the TNTs can be activated by sun light, and generate photoexcited electron‐hole pairs, which can react with H2O and O2 to produce ⋅OH and ⋅O2− radicals, resulting in degradation of waste water. On the other hand, the reaction scheme has a little changed when the TNTs modified by Zn‐TCPP NS. A high‐efficiency visible‐light responsive tube‐sheet nanocomposite (Zn‐TCPP NS/TNTs) was fabricated by an improved hydrothermal method. The composites containing 5% Zn‐TCPP NS show a marvelous photocatalytic performance for the initial high concentration MB solution (30 mg/l) under visible light, which was about 2 times more than that of the pure TNTs. The electrochemical impedance spectroscopy of the 5% Zn‐TCPP NS/TNTs composites are obviously lower than the pure TNTs, and the photocurrent is 3.8 times than the pure TNTs. [ABSTRACT FROM AUTHOR]

The stable isotope technique provides the possibility to trace ancient textiles because the technique is associated with advantages such as trace indication, fast detection, and accurate results. Since different cocooning conditions may impact cocoons even under identical habitats, it is important to investigate the effects of different cocooning temperatures and humidity on the isotope incorporation values in the cocoons. In this study, silk fibers were reeled under different conditions of temperature and humidity, followed by analysis of the secondary structure of cocoon proteins and isotope incorporation patterns. We found that the deviations in carbon isotope values of silk under different cocooning conditions could reach up to 0.76‰, while the deviation in carbon isotope values at different locations of a single silk was 2.75‰. Further, during the cocooning process, depletion of the 13C-isotope at different locations of the silk fibers was observed, reducing the δ13C values. We proposed that the changes in carbon isotopes in silk were related to the content of sericin and silk fibroin in silk. Finally, we did not observe a significant difference in isotope ratios in degummed cocoons. In summary, the 13C isotope was enriched in sericin, whereas 15N was enriched in fibroin, and these findings provide basic information for tracing the provenance of silks. [ABSTRACT FROM AUTHOR]

Hydrogen, oxygen, carbon, and nitrogen isotopes derived from three different strains of silkworms at different life stages involved in silkworm rearing, were measured to understand the fractionation characteristics of stable isotopes at different stages of silkworm development, and to trace the movement of these isotopes from food to larva to excrement and finally to silk. We found that silkworm strain had little effect on δ2H, δ18O and δ13C values. However, a large difference was found in the δ15N levels of newly-hatched silkworms between Jingsong Haoyue and Hua Kang No. 3 orthogonal strains, suggesting that the mating and egg laying differences may result in an inconsistent kinetic nitrogen isotope fractionation. The δ13C values of silkworm pupae and silkworm cocoon also displayed significant differences, suggesting that heavy carbon isotopes are greatly fractionated from the larva to the silk during cocoon formation. Overall, these results may be used to clarify the relationship between isotope fractionation and the ecological process of the Bombyx mori and expand our ability to resolve stable isotope anomalies at a small regional-scale level. [ABSTRACT FROM AUTHOR]

Dynamic regulation of QTLs remains mysterious. Single segment substitution lines (SSSLs) and conditional QTL mapping and functional QTL mappings are ideal materials and methods to explore dynamics of QTLs for complex traits. This paper analyzed the dynamics of QTLs on plant height with SSSLs in rice. Five SSSLs were verified with plant height QTLs first. All five QTLs had significant positive effects at one or more developmental stages except QTL1. They interacted each other, with negative effects before 49 d after transplanting and positive effects since then. The five QTLs selectively expressed in specific periods, mainly in the periods from 35 to 42 d and from 49 to 56 d after transplanting. Expressions of epistasis were dispersedly in various periods, negative effects appearing mainly before 35 d. The five QTLs brought the inflexion point ahead of schedule, accelerated growth and degradation, and changed the peak plant height, while their interactions had the opposite effects. The information will be helpful to understand the genetic mechanism for developmental traits. [ABSTRACT FROM AUTHOR]

The characterization of ancient silk provides significant historical information and contribute to the identification of the origin of the material. At present, there are many ways to characterize silk. However, on-site identification of ancient silk remains a crucial challenge. In this study, a paper chromatography system consisting of a colloidal gold immunochromatographic strip (GICS) and a time-resolved fluorescence immunochromatographic strip (TICS) is proposed to meet this challenge. On the basis of the original paper chromatography technique, a monoclonal antibody against silk fibroin (SF) was prepared and applied in this new paper chromatography system. Both the GICS and the TICS showed good sensitivity, specificity and reliability, with the limit of detection for silk fibroin being 30 μg/mL and 49.20 ng/mL, respectively. Moreover, there was no cross reaction with possible interferents. Furthermore, the GICS had acceptable thermal stability. The recovery of the TICS assay was in the range from 98.12% to 103%, and the variation coefficient was from 5.34% to 6.93%. This work significantly improves access to scientific information at archaeological sites, providing new scientific evidence for exploring the origin and transmission roadmap of ancient silk. [ABSTRACT FROM AUTHOR]

Application of transition metal elements in catalysis has become a research hotspot in recent years. Here, two kinds of transition metal-centered HER electrocatalyst of Co(Ⅱ)TPP-based coordination compounds and Fe(Ⅲ)TPP-based coordination compounds are reported. Both of coordination compounds show high photocurrent response and excellent hydrogen evolution activity. The most attraction is that FeTPP-OA/PVP58, FeTPP-PTA/PVP58, FeTPP-OA/PVP1300 and FeTPP-PTA/PVP1300 possess a special surface with a big spine-like cross which is different to the regular pyramid morphology of the other coordination compounds, and these coordination compounds display superior HER performance compare to the other samples. Especially, FeTPP-OA/PVP58 exhibits a low overpotential of 83 mV at the current density of 10 mA cm−2 and an ultralow Tafel slope of 39 mV dec−1 which is close to the Pt/C (29 mV dec−1). The low charge transfer resistance of 14.4 Ω and high photocurrent of 3 μA under visible light illumination also reveal the outstanding photoelectrochemical property of FeTPP-OA/PVP58. This work provides a novel insight into the design of transition metal-centered HER electrocatalyst with high-efficiency electrocatalytic activity and low cost. • An 1D linear Co(Ⅱ) and Fe(Ⅲ)TPP-based coordination compounds was fabricated. • 1D linear coordination compounds possess the regular pyramid morphology. • Both coordination compounds all show high photocurrent response and excellent hydrogen evolution activity. • The complexes have a great potential for HER electrocatalysts with high-efficiency activity and low cost. [ABSTRACT FROM AUTHOR]

• Stable isotope technique was firstly used to analyze ancient and artificial aged silk fabrics. • The stable isotope ratios of ancient silk fabrics under various excavation environments display different trends. • Heavy stable isotopes were enriched during degradation of the silk fabrics under most aging conditions. • Degradation of silk fabrics is a significant cause of stable isotope offset in historical silk fabrics. • Different aging factors should be considered when tracing the origin of historic silk fabrics using stable isotope techniques. Understanding the degradation of silk fibers and tracing silk fabrics from archeological sites have always been challenging. The stable isotope technique provides the possibility to trace ancient textiles, especially for the controversial issue of the silk origin. Chinese historic silk fabrics from the Xia dynasty (about 4000 years ago), Warring States period (B.C. 475- B.C. 221), Tang dynasty (A.D. 618- A.D. 907), Southern Song period (A.D. 1127- A.D. 1279), Ming dynasty (A.D. 1368- A.D.1644), and Qing dynasty (A.D. 1636- A.D. 1912) as well as some artificially aged silk specimens have been examined by scanning electron microscopy (SEM), attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, and isotope ratio mass spectrometry (IRMS) to investigate their degradation for traceability and preservation. It has been found that the surface morphology and secondary structure of silk were destroyed in the degradation process. Under most aging modes, the silk fabrics were enriched with heavy stable isotopes after degradation. In the case of charring, the isotopic ratios of heavy hydrogen and oxygen isotopes showed different variation tendencies, which need to be further studied for better understanding. The results revealed that stable isotope ratios of silk fabrics are affected by different aging conditions. The degradation of silk fabrics is an important cause of stable isotope offset in historical silk fabrics. Overall, this study provides useful insights into the silk degradation mechanism and can serve as a useful reference for tracing the rich textile heritage. [ABSTRACT FROM AUTHOR]

The origin and dissemination of silk have been hotly debated in the field of archaeology, and the key to resolving this controversy lies in the detection and species identification of ancient silk microtraces. Herein, a taxonomically specific anti-fibroin monoclonal antibody was successfully prepared and a layer-by-layer self assembly electrochemical immunosensor was innovatively proposed for detecting silk traces based on flexible carbon cloth. The immunosensor possessed a broad linear range of 10−2-103 ng mL−1 and a detection limit of 2.15 pg mL−1 for the ultrasensitive detection of Bombyx mori silk traces. In addition, the elaborate immunosensor exhibited satisfactory high specificity, storage stability and reproducibility. In particular, the qualitative and quantitative performance of the immunosensor was excellent in the analysis of archaeological samples. Therefore, this work demonstrates that the proposed method not only provides a reliable analytical tool for exploring the origin and spread of archaeological silk, but also improves our understanding of how to use emerging materials like two-dimensional titanium carbide to creat innovative biosensors. [ABSTRACT FROM AUTHOR]

Hydrogen production from electrocatalytic water splitting has aroused extensive attention in many fields recently. Fabrication of low-cost and high-efficiency electrocatalysts are still an urgent and challenging work. Porphyrins as visible-light photosensitizers have been extensively utilized in visible-light photocatalysts and photoelectronic materials. So, fabrication of novel porphyrin-based complexes will be benefited for high-efficiency hydrogen evolution and photoelectric response. Here a series of zirconium porphyrin-based coordination complexes were successfully fabricated via a facile two-step strategy. Due to the unique long chain-like structure and low charge-transfer resistance, the zirconium porphyrin-based coordination complexes displayed excellent electrocatalytic performance for hydrogen evolution reaction. The ZrTPP-PTA-1 showed a low overpotential of 60 mV at the current density 10 mA cm−2 and a Tafel slope of 87 mV dec−1 with an ultralow electron transfer resistance of 17.5 Ω. In addition, a quick photocurrent response occurred for these coordination complexes with a visible-light illumination. The photocurrent of the ZrTPP-OA-2 rised up to 2.5 μA under visible-light irradiation. With this pleasant result, these zirconium porphyrin-based coordination complexes have a great potential to become available alternative of current noble electrocatalysts for photoelectric application. • 1D long chain-like porphyrin-based coordination complexes were fabricated. • 1D nanostructure is in favor of photogenerated charges separation and transfer. • The complexes have high-efficiency hydrogen evolution. • The complexes have better photoelectric response. • The complexes have great potential for electrocatalyst and photoelectric material. [ABSTRACT FROM AUTHOR]

A novel high-efficiency composite photocatalyst, carbon quantum dots (CQDs) are embedded onto out-surface surface of the TiO 2 nanotubes (TNTs) with high percentage of photocatalytic reactive facets, was fabricated through an improved hydrothermal method. The characterization results showed that the CQDs was chemically adhered to out-surface of the TNTs through the C O and/or C O bonds formed between the CQDs and TNTs. The photocatalytic performance of as-prepared photocatalysts was evaluated to degrade methylene blue (MB) solution under the visible light. The as-prepared photocatalysts had a marvelous photocatalytic performance and the CQDs/TNTs-0.2 sample had the best photocatalytic performance with a decolorization rate of 91.3% and approximately 2 times more than that of pure TNTs for the high initial concentration of MB solution (30 mg/l) within 50 min under visible-light irradiation. The CQDs with excellent Up-Conversion Photoluminescence(UCPL)properties as co-catalysts can covert long wavelength light (>600 nm) absorbed from infrared light into visible light (<600 nm), which activates the TNTs to produce electron-hole pairs. Moreover, the CQDs also can capture the photoexcited electrons and prolong the lifetime of the photoexcited charges. In addition, the stacking interaction of the π-π bonds between the CQDs and the dyes of the benzene ring structure would be beneficial for enhancing the absorption performance of the CQDs/TNTs photocatalysts. The photocatalytic mechanism and process have also been discussed in detail according to the characterization and photodegradation results. This work is of great interest to introduce a new visible-light photocatalyst for the treatment of organic wastewater and protect environment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ultrasensitive detection is critical for investigating silk's origin and spread. • A dual-responsive PEC immunosensor was prepared for silk microtrace detection. • The sensor was developed by in-situ growth of Ag 2 S on ZnO-MXene nanocomposites. • The sensor exhibits excellent taxonomic specificity, repeatability and stability. • The dual-responsive PEC immunosensor is applied for detection of real silk samples. Developing an effective analytical method for microtrace detection of ancient silk is highly desirable and vitally crucial for exploring the origin and spread of silk. Herein, a taxonomically specific anti-fibroin monoclonal antibody was prepared and an elaborate visible/near-infrared (vis/NIR) photoelectrochemical (PEC) immunosensor was proposed. The sensor employed Ag 2 S nanoparticles (NPs) grown in situ on ZnO nanowire array-MXene nanocomposites (ZnO-MX) via a sonochemical method as a photosensitive material. The experimental results illustrated that the ZnO-MX/Ag 2 S-based sensor presented 6.8 times larger PEC responses than a ZnO-MX-based sensor under visible light illumination, and the PEC signal of the ZnO-MX/Ag 2 S nanocomposites was 30 times as high as that of ZnO-MX under 808 nm NIR light, indicating enhanced photoelectric activity and a matched energy band structure of ZnO with MXene and Ag 2 S. This PEC immunosensor exhibited excellent potential for the ultrasensitive detection of Bombyx mori silk traces due to its wide linear range of 0.005–50 ng mL−1 and low detection limit of 1.51 pg mL−1. Additionally, the immunosensor showed outstanding specificity, stability, and repeatability, particularly for the qualitative detection of archeological artifacts. Given its aforementioned benefits, ZnO-MX/Ag 2 S nanocomposites are potentially attractive photoactive materials for use in vis/NIR PEC immunosensors. Moreover, this demonstrated method offers a feasible method to investigate the history and distribution of ancient silk. [ABSTRACT FROM AUTHOR]

The identification of ancient wool is of great importance in archaeology. Despite lots of meaningful information can be achieved by conventional detection methods, that is, light and electron microscopy, spectroscopy, and chromatography, the efficacy is likely to be limited in the detection of ancient samples with contamination or severe degradation. In this work, an immunoassay was proposed and performed for the identification of ancient wool. First, a specific antibody, which has the benefits of low cost, easy operation, and extensive applicability, was developed directly through immunizing rabbits with complete antigen (keratin). Then, an enzyme-linked immunosorbent assay (ELISA) and a colloidal gold-labelled immunochromatographic strip (ICS) were developed to qualitatively identify the corresponding protein in ancient wool samples unearthed from Kazakhstan and China. The anti-keratin antibody exhibited high sensitivity and specificity for the identification of modern and ancient wool. The limit of detection (LOD) of the ELISA method was 10 ng/mL, and no cross-reactions with other interfering antigens have been noted. It is concluded that the immunoassays are reliable methods for the identification of ancient wool. [ABSTRACT FROM AUTHOR]

Iron(III) meso -tetra(4-carboxyphenyl) porphyrin (FeTCPP) loaded on the surface of TiO 2 nanotubes (TNTs) has been successfully prepared through improved hydrothermal and heating reflux process. The new photocatalyst has been characterized and analyzed by TEM/EDS, BET, XRD, FT-IR, DRS, PL, XPS and EPR. The photocatalytic activity of FeTCPP/TNT nanocomposite was evaluated by the photodegradation of MB under visible light irradiation. The degradation results showed a purification of more than 90% MB in simulating wastewater, and confirmed that the prepared FeTCPP/TNT nanocomposite has acquired superior photocatalytic activitiy. The 6 times cycled results suggested the great stability of the photocatalyst. These results confirmed the FeTCPP played an important role in capturing photons and expanding the absorption wavelength to the visible light region, and the FeTCPP/TNT photocatalyst is also beneficial for the electron transfer and long-distance transmission, and could efficiently increase the separation of the electron-hole pairs, and accelerate the decomposition of organic pollutants. In addition, nano-sized structures can increase adsorption capability. [ABSTRACT FROM AUTHOR]

Ancient silk has important historical, artistic, and scientific value, and its origin and spread have always been a research hotspot. However, traditional analytical methods have encountered great challenges in the analysis of ancient silk microtraces due to the problems of large sample consumption, serious contamination, and degradation. To overcome this problem, a taxonomically specific anti-fibroin monoclonal antibody was designed and successfully prepared by animal immunization, and a novel photoelectrochemical immunosensor based on the antibody and ZnO nanowires array was constructed for the first time. This photoelectrochemical immunosensor possessed a detection limit as low as 0.56 ng mL−1 and a linear range from 1 to 1000 ng mL−1, showing great potential in the ultrasensitive detection of silk trace. In addition, the elaborate immunosensor demonstrated preeminent performances in the specificity, stability, and reproducibility, especially in the qualitative and quantitative detection of soil samples extracted from Sanxingdui archeological sites. Therefore, the proposed method not only provides a powerful analytical tool for exploring the origin and spread of ancient silk but also provides a reference for the study of other types of protein artifacts. • Ultrasensitive detection for silk microtraces has great significance to investigate the origin and spread of ancient silk. • Application innovation: it was the first time to design and prepare a PEC immunosensor in the archaeological field. • Method innovation: this work fabricated a PEC immunosensor based on CdS QDs and Ag NPs co-sensitized ZnO NWA. • The PEC immunosensor exhibited a low LOD of 0.56 ng mL−1 and was excellent in taxonomic specificity and stability. [ABSTRACT FROM AUTHOR]

Meso-tetra (4-carboxyphenyl) porphyrin (H 2 TCPP) loaded on the surface of TiO 2 nanotubes (TNTs) by modification of reduced graphene oxide (rGO) nanostructures has been successfully performed through improved hydrothermal and heating reflux composite technology. The influence of rGO and H 2 TCPP on the co-photocatalytic behavior of TNT during the degradation of Methylene blue (MB) were studied. The novel photocatalysts have been characterized and analyzed by high-resolution transmission electron microscopy (TEM), elemental mapping by energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, ultraviolet–visible diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy (PL) and electron paramagnetic resonance (EPR). The results from these investigations provide a deeper insight into the materials chemistry of H 2 TCPP/rGO-TNT nanocomposites. Additionally, the photocatalytic activity was evaluated by the photodegradation of MB under irradiation with visible light. The degradation results showed a purification of more than 92% MB in wastewater, which is about 4.3 times higher than that of the pure TNT. The results confirm that the prepared H 2 TCPP/rGO-TNT nanocomposites possess superior absorption and co-photocatalytic activities. First, graphene works as the adsorbent, electron acceptor and transporter to efficiently increase the separation of the electron–hole pairs. Then it can accelerate the decomposition of organic pollutants. Second, the H 2 TCPP plays a critical role in capturing photons and expands the absorption wavelength to the visible light region when dealing with water resource. [ABSTRACT FROM AUTHOR]

In this paper, TiO 2 nanotubes (TNT) co-sensitized with copper(II) meso -tetra(4-carboxyphenyl)porphyrin (CuTCPP) and reduced graphene oxide nanosheets (rGO), which was fabricated through two-step improved hydrothermal method and heating reflux process. The effect of rGO and CuTCPP on the co-photocatalytic behavior of TNT for the degradation of Methylene Blue (MB) were measured under visible light irradiation. The photocatalysts have been characterized and analyzed by high-resolution transmission electron microscopy (TEM), selected area electronic diffraction (SAED), elemental mapping by energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) and electron paramagnetic resonance (EPR). The results provide a deeper insight into the co-photocatalytic mechanism of CuTCPP/rGO-TNT nanocomposites. The degradation results showed a purification of more than 95% MB in wastewater, which is about 5 times higher than that of the pure TNT. The results also confirm the prepared CuTCPP/rGO-TNT nanocomposites possess superior co-photocatalytic activities. [ABSTRACT FROM AUTHOR]

Silica-alumina gel with micrometer-sized macropores and nanometer-sized mesopores has excellent advantages in humidity control properties. The macropores provide pathways for rapid H 2 O molecular transportation while the mesopores present a large surface area. An amorphous spherical silica-alumina beads material with a distinct bimodal pore structure was prepared by sol–gel reactions of tetraethoxysilane (TEOS) and aluminum nitrate in the presence of poly(ethyleneoxide) (PEO). It features high moisture adsorption capacity, super fast response to humidity changes, small equilibrium humidity control range and macroscopic spherical morphology. The appearance and structural properties of the material were investigated by digital camera, scanning electronic microscope (SEM) and thermal gravimetry and differential thermal analyses (TGA/DTA). The porosity features are further established by N 2 sorption experiments and pore size distribution analysis. The bonding characteristics and coordination features around aluminum have been studied using Fourier transform infrared spectroscopy (FTIR) and 27 Al magic angle spinning nuclear magnetic resonance ( 27 Al MAS NMR). The humidity control performance of the material at relative humidity was measured. The results revealed that the material kept a relative humidity in the range of 39.3–40.3%, 47.6–50.7% and 57.2–60.7%, respectively, under three different pre-treating conditions. And the humidity controlling equilibrium levels were all reached within 3 h. Therefore, the material could maintain a suitable relative humidity of 40–60% in enclosed spaces such as showcases in museums and galleries. [ABSTRACT FROM AUTHOR]

Highlights: [•] We report a new process to prepare humidity control materials. [•] The process is easy to perform and does not produce any harmful resultant. [•] This material can serve as intelligent humidity control material. [•] Good properties depend on the surface area and the distribution of pores. [•] Possible reasons for humidity control properties are discussed. [Copyright &y& Elsevier]

Konjac glucomannan nanospheres (KNSs) were synthesized via an inverse emulsion crosslinking method using epoxy chloropropane as a crosslinking agent under alkaline conditions. The KNSs are narrow-dispersed with an average diameter of 40–50 nm. They are easily separated even at the nanoscale—this is favorable for improving the flow nature of various materials during processing applications. The KNSs have much higher moisture adsorption and desorption ability than konjac glucomannan. This high total surface activation suggests applications as easily recycled adsorbents. Thus, this paper describes an effective and convenient way to prepare narrow-dispersed natural polymer microspheres with good processability, adsorption, and desorption properties. [ABSTRACT FROM AUTHOR]

• The e-skin was fabricated by low cost and simple process. • The e-skin supercapacitors showed a larger areal specific capacitance and a high energy density. • The e-skin sensors showed superior sensitivity including stretching and bending. • The e-skin has broad prospects of robots, prosthetics and stretchable wearable devices. Electronic skin (e-skin) with natural stimuli is a key factor in prosthetics, robotics, and wearable electronics. At present, most traditional stretchable e-skins fabricated by predesigning complex 3D structures are unsuitable in commercial applications. Energy storage devices with stretchable and arbitrary shapes can widely adapt to wearable electronics. Stretchable supercapacitors and sensors have been used as the primary energy supplies in prosthetics, robotics, and wearable electronics in recent years, because of their superior power density and long calendar life. Here, stretchable energy storage e-skin supercapacitors and sensors were fabricated using two-sublayered silver nanowire (AgNW)/MnO 2 NW (MNW) hybrid conductive networks fixed into the polydimethylsiloxane (PDMS) layer and sandwiched using AgNW/MNW film electrodes and PVA–KOH solid electrolyte. The obtained e-skin device showed large areal specific capacitance, excellent capacity retention, coulombic efficiency of 2000 cycles, and high energy density. The multifunctional e-skin sensors showed an areal specific capacitance of 371 m F cm−2 at a current density of 1 mA cm−2, extended to 160 %, and had superior sensitivity including stretching and bending by hand. Therefore, the multifunctional e-skin sensors are suitable in robotics, prosthetics, and other stretchable wearable devices. [ABSTRACT FROM AUTHOR]

Achieving efficient identification of silk protein requires highly sensitive analytical techniques and favorable extraction methods, which is of great significance to the research of ancient silk, especially for the controversial issue of the silk origin. In this paper, proteomics and western blot were proposed to analyze the silk proteins of Bombyx mori (B. mori) and Antheraea pernyi (A. pernyi) dissolved by different methods. First, the differences in secondary structure were detected via spectroscopy. LC-MS/MS was then employed to characterize the peptides of silk proteins precisely. LiBr solution exhibited outstanding dissolution effect on B. mori cocoon, with 87 proteins detected; while copper-ethylenediamine solution (CED) was more appropriate for A. pernyi cocoon, and 16 proteins were identified in A. pernyi -CED. In addition to fibroin and sericin, abundant seroins, enzymes, protease inhibitors, other functional proteins and uncharacterized proteins were detected. Based on the LC-MS/MS data, diagnostic antibodies for the two species were prepared, and fibroin was successfully identified by western blot assay because both dissolution methods were gentle and did not destroy the antigenic epitopes in the protein molecule. Owing to their good specificity and high sensitivity, these diagnostic antibodies have good application prospects in immunoassays of different silk species. This study presents the comprehensive analysis on silk identification of proteins from B. mori and A. pernyi extracted by different methods via the proteomic and immunology as well as the conventional approaches. Great coverage of two cocoon proteomes was accomplished, which demonstrated the outstanding difference in components and abundance. Based on the proteomics analysis, the diagnostic antibodies against two species were prepared and identified the corresponding fibroin successfully in the completed protein mixtures. To our knowledge, the proteomic and immunology procedures with high efficiency, sensitivity and specificity are novel analysis on the silk identification and has great potential in the field of ancient silk detection. Unlabelled Image • The secondary structure of silk proteins obtained by different methods were well characterized. • The iBAQ proteomic analysis indicates differences in silk proteins of Bombyx mori (B. mori) and Antheraea pernyi (A. pernyi). • Highly sensitive polyclonal antibodies were prepared successfully to silk proteins of B. mori and A. pernyi , respectively. [ABSTRACT FROM AUTHOR]

In recent years, increasing attention has been paid to the origin, transmission and communication of silk. However, this is still an unsolved mystery in archaeology. The identification of silk-producing species, especially silk produced by Bombyx mori (B. mori) and Antheraea pernyi (A. pernyi), is of key significance to address this challenge. In this study, two innovative methods, i.e. immunology and proteomics, were proposed and successfully established for the species identification of silks. ELISAs result demonstrated that the two prepared antibodies exhibited high sensitivity and specificity in distinguishing B. mori and A. pernyi silk. No cross-reactivity with each other was observed. Moreover, biomarkers were obtained for Bombyx and Antheraea through proteomic analysis. It was also confirmed that the biomarkers were suitable for identifying the species that produced a given silk sample. Compared with conventional methods for distinguishing silk species, immunological and proteomics techniques used in tandem can provide intact information and have the potential to provide accurate and reliable information for species identification. [ABSTRACT FROM AUTHOR]