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Two-dimensional metal-benzenehexathial sheets are promising catalysts for the oxygen reduction reaction.

This review covers recent progress and advancements in bio‐templating nanomaterials for use in energy applications. Viruses, bacteria, and fungus, as well as plant and animal biomasses such as woods, coffee grounds, and crab shells, can be used as the templates or carbon sources for metal‐ and carbon‐based nanomaterials. Here we provide an overview of each of these materials as a template, with emphasis on the synthesis methods and qualities of nanomaterials fabricated using these templates. Research in this field is understandably diverse, as such, we aim to further its development by providing a timely summary of current research. We anticipate that this field will continue to prove highly applicable to the salient and growing topics of renewable energy.

When stone objects are excavated at archeological sites, they are often covered with crusts of mineral deposits on the surface, which seriously obscure their aesthetic value, especially in the case...

The traditional method for the identification of paper from different origins relies on microscopy to observe the fiber morphology, which requires professional experience. In this paper, pyrolysis-gas chromatography-mass spectrometry was utilized to analyze five types of traditional Chinese handmade papers, e.g., ramie paper, bamboo paper, bark fiber paper (mulberry paper and kozo paper), and Langdu paper. The results demonstrated that this method can be used to differentiate the four types of handmade papers. A high phenolic compound content was detected in bamboo paper; macromolecular triterpenoids, e.g., β – amyrin, α – amyrin, and stigmastan- 3,5-diene were found in mulberry paper and kozo paper; while those compounds were not found in ramie paper. In particular, a large quantity of phytosterol compounds were found for the first time in Langdu paper. This not only can be used to differentiate Langdu paper from others, but also it helps to explain why Langdu paper can resist insect and mildew activities. Results of the study can provide experimental reference for characterization of traditional handmade Chinese papers via pyrolysis-gas chromatography-mass spectrometry.

Oils were often used as additives in lacquering process in ancient time, and the proportion of oil to lacquer is crucial for the quality of the lacquer objects. In order to quantitative analyze the proportion of oil to lacquer in the ancient lacquer objects, Near-infrared spectroscopy (NIRS), a non-destructive method was studied. In this research, a partial least squares (PLS) model of reference samples for quantitative analysis of lacquer films was established. When evaluating the final model, factors such as correlation coefficient (R) and the root mean square error of prediction (RMSEP) were considered. The final optimal results of the PLS model showed that RMSEP and correlation coefficients (R) in the calibration set were 0.112 and above 0.98, respectively, demonstrating that NIRS can be used to the quantification analysis of lacquer film. Subsequently the developed PLS model was applied to quantitatively analyze the lacquer samples from the Buddhist statue and altar of Qing dynasty, while thermally assisted hydrolysis–methylation for pyrolysis-gas chromatography-mass spectrometry (THM-Py-GC/MS) was applied for the qualitative analysis. The results show that urushiol-based lacquer and tung oil were used and the ratios of oil in lacquer are varied in different objects for special purposes. For the first time, the proportions of oil to lacquer were revealed in the ancient lacquer objects, which is significant to enhance the knowledge about lacquering techniques in ancient times.

Laryngeal squamous cell carcinoma is one of the most common cancer-related causes of death worldwide. Thus, there is a constant need for improvement in drug development to promote treatment of this malignancy. In the present study, we identified a natural phytochemical, Ursolic acid, as a potent compound to counter laryngeal squamous cell carcinoma using HEp-2 cell line. Ursolic acid is capable of impeding proliferation and provoking apoptosis of HEp-2 cells. Interestingly, these anti-proliferative and proapoptotic effects is attributed to stimulation of ROS synthesis. In addition, we discovered that this UA-induced ROS stimulation is linked to the activation of MAPKs, PI3K/Akt, NF-κB and STAT3 signaling pathways. Our study characterized Ursolic acid as a potent anti-carcinoma drug with a multitargeting strategy, which enable it a novel and plausible treatment to laryngeal squamous cell carcinoma.

Zinc-based batteries are a scalable and safe alternative to Lithium-ion batteries due to the nature of abundance, low cost and easy to process. In this work, we have successfully synthesized porous zinc electrodes (PZEs) via a gel-binder method that can stably charge and discharge for over 700 h at 1 mA cm−2 before showing signs of failure. We compared PZEs synthesized from small (60 nm), intermediate (10 μm), and large (150 μm) zinc particles to determine which surface features are best suited to mitigate dendritic growth and to improve electrolyte stability. The zinc deposits on the large PZE shows a stable and flat morphology, which does not form the hexagonal close-packed (HCP) crystal structure that is typically seen on planar zinc anodes. The intermediate PZE has an increased affinity to deposit onto the glass microfiber separator leading to a decrease of active material on the anode that causes instability during galvanostatic cycling. Both planar zinc and small PZE show HCP deposits that are normal to the surface, which result in very poor electrochemical performance. As the particle size increases, the deposits transition from HCP crystals to flat amorphous metal deposits, increasing cyclic stability.

Being inspired by nature, a series of experiments was carried out to deposit a calcium oxalate layer on the surface of the stone by the reaction between carbonate rock and oxalate salt. To increase the anti-dissolution properties of the calcium oxalate layer, the use of mixed oxalate solution has been proposed in the literature by two main routes: (1) adding acid agent to ammonium oxalate, which has the advantage of changing the particle structure and reducing layer porosity, and (2) using neutral methyl oxalate solution, which has the advantage of surface coverage due to slowly hydrolysis. In this study, we investigated the sequential application of ammonium oxalate, methyl oxalate, neutral mixed, and calcium acetate acid mixed solution. With this method, calcium carbonate and calcium oxalate solution can react inside the stone to reinforce it. The protective film’s coverage area can then be increased using dimethyl oxalate neutral mixed solution, and the crystal morphology can be modified with calcium oxalate acid mixed solution. The anti-dissolution properties of the coating were investigated using both a custom-designed apparatus and a selective outdoor environment. The coating displayed good acid resistance properties at pH 2–4. After one year of exposure, the coating is firmly bonded with the stone.

The fuel residues in two bronze lamps excavated from Haihunhou Tomb in the Han Dynasty, in Jiangxi Province, China, were studied in this paper. The techniques of Fourier transform infrared (FT-IR) spectroscopy and pyrolysis–gas chromatography–mass spectrometry with thermal-assisted hydrolysis and methylation (THM-Py–GC/MS) were used to characterize the materials. Long-chain fatty acids, fatty alcohols and hydrocarbons were detected as the main components. By comparing the reference materials of beeswax and Chinese wax, the residues in the lamps were identified as beeswax. Furthermore, according to the morphology of the remains of the lamp fuel, the fuel remains were probably melted and then solidified, which suggests the lamps were used. Wax was found to have been used as an illuminating fuel as early as the Han Dynasty, enriching scholarly knowledge about the lighting materials used in ancient China.

A coaxial poly(phthalazinone ether sulfone ketone)/polyvinylidene fluoride fibrous membrane used for lithium-ion batteries was prepared by the electrospinning technique. The suitable processing parameters were chosen to obtain the core PPESK fibers with small diameter and shell PVDF fibers with large diameter simultaneously. The prepared coaxial PPESK/PVDF fibrous membranes exhibit superior thermal shutdown property and thermal dimensional stability. Meanwhile, the coaxial PPESK/PVDF membranes show larger porosity, better electrolyte wettability and higher ionic conductivity in comparison with the commercial PP/PE/PP separators. In addition, the coins cells using coaxial PPESK/PVDF membranes show excellent cycle performance, which demonstrates the membranes have the potential to be used as separators for high-performance lithium-ion batteries.

For authenticity and conservation purposes, the precious historical rubbings preserved in Wuyuan Museum were studied by multi-analytical techniques including Pyrolysis gas chromatography-mass spectrometry (Py-GC/MS), SEM-EDS and Herzberg staining method. Through Py-GC/MS analyses, five types of constituents could be detected: (1) polycyclic aromatic hydrocarbons from soot; (2) retene and methyl dehydroabietate from tar of conifer wood; (3) marker compounds of egg; (4) additives of menthol and curcumene compounds; (5) biochemical compounds of bark paper. Based on this analytical results, the ink type, binding media and additives in the ink, as well as the fiber origin source of the rubbing paper could be concluded. The materials information of the rubbings obtained through this study could not only provide evidence for its authenticity, but also supply scientific support for its conservation and restoration.

Wooden lacquerware cultural relics are very characteristic cultural relics in China. Ancient wooden lacquerware excavated underground has relatively intact paint cover, but its bodies are mostly decayed, generally with a moisture content of 100-400%, and in some cases going as high as 700%. Therefore, dehydration and reinforcement of water-saturated bamboo, wood, and lacquer artifacts is the most critical step for restoration and protection. In order to protect the unearthed wooden lacquerware in a targeted manner, it is necessary to conduct a detailed pre-protection analysis of the cultural relics. In 2014 and 2015, the Hubei Provincial Institute of Cultural Relics and Archaeology worked with Jingzhou Cultural Relics Conservation Center and many other organizations to respectively carried out a more comprehensive excavation of the Caomenwan and Guojiamiao Cemeteries, and cleared more than 110 tombs. The tomb in question was inscribed on the list of China's Ten Major Archaeological Discoveries in 2014. From the tomb 186 water-saturated pieces of lacquered woodware were unearthed. Due to the biological and microbial corrosion in the buried environment, the lacquered woodware urgently needed protective dehydration. In order to better protect the cultural relics and retain as much of the original information as possible, it is necessary to analyze this batch of lacquered woodware before placing them under protection.

Background Triazine coccidiostats are widely used in chickens and turkeys for coccidiosis control. Ethanamizuril is a novel triazine compound that exhibits anticoccidial activity in poultry. This study was designed to evaluate the subchronic toxicity of ethanamizuril in beagle dogs at doses of 12, 60 or 300 mg/kg/day in diet for 90 days. Results Ethanamizuril was well tolerated at low and middle dosages in beagle dogs, and no drug-related toxical effects were observaed in terms of survival, clinical observations, organs weight and damage in these dose groups. However, in high dose administration group, food consumption and histologic changes in kidneys were noticed in both sexes of beagle dog, although the renal lesions were finally resolved at the end of 4 weeks exposure of ethanamizuril. Conclusions No-observed-adverse-effect level (NOAEL) was considered for ethanamizuril at dose of 60 mg/kg/day in Beagle dog. This result added toxicity effects of ethanamizuril to the safety database, which might guide safely using of ethanamizuril as a novel coccidiostat.

Red discolorations are an effloresce phenomenon detect on the surface of stone objects and considered as damage factor in both esthetic and conservation points of view. It is very difficult to remove and seldom report about their weathering mechanism. Recently, numerous of red discolorations have affected the limestone objects of Lingyan Temple in Shandong province, one of the most important building materials in China. In order to set up the appropriate conservation remedy, it is essential to identify the origin, characteristics, composition, and the formation process of red discolorations. Several analytical and investigation techniques, such as X-ray fluorescence spectroscopy (XRF), X-ray diffraction (XRD), Micro-Raman spectroscopy (Raman), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) equipped with energy dispersive spectrometer (EDS) were used to better understand the red discolorations. The results demonstrated that the discolorations on limestone surface have been caused by carbonic acid weathering process. The red discolorations consisted mainly of kutnohorite (Ca(Fe,Mg,Mn)CO3) and iron oxides. They showed tabular, lamellar, and granular morphologies, which originated from the in situ carbonic acid weathering of kutnohorite. After rainfall, the Ca, Mg, Mn ions with relatively high solubility were primarily leached from carbonatite phases. It was resulting in the sedimentation of red iron oxides through a chemical reaction and physical adhesion. Based on those analyses, a chelating agent (ethylenediamine tetraacetic acid disodium salt) was chosen to remove theses red discolorations on the stone object.

Additional file 1. The ARRIVE Guidelines Checklist.

Sodium-ion batteries (SIBs) have generated substantial interest because of the geopolitical uncertainty of the availability of lithium, as well as the potential cost savings associated with replacing lithium with sodium. One of the key technological impediments to SIBs is the availability of a high-capacity anode material. Here, we show that biotemplated zinc sulfide nanofibers, prepared using the M13 bacteriophage template, have the potential to be used for this purpose. We investigated the effect of both annealing and carbon coating on the electrochemical performance of these materials. Biotemplated zinc sulfide nanofibers, when coated with a few-nanometer carbon layer, could deliver a reversible capacity of 603 mAh/g at 100 mA/g discharge rate, even when the zinc sulfide loading is as high as 70%. The initial Coulombic efficiency reached 71%, and the electrode could be cycled for at least 100 cycles.

Carefully designed solid-electrolyte interphases are required for stable, reversible and efficient electrochemical energy storage in batteries. We report that hybrid battery anodes created by depositing an electrochemically active metal (for example, Sn, In or Si) on a reactive alkali metal electrode by a facile ion-exchange chemistry lead to very high exchange currents and stable long-term performance of electrochemical cells based on Li and Na electrodes. By means of direct visualization and ex situ electrodeposition studies, Sn–Li anodes are shown to be stable at 3 mA cm−2 and 3 mAh cm−2. Prototype full cells in which the hybrid anodes are paired with high-loading LiNi0.8Co0.15Al0.05O2(NCA) cathodes are also reported. As a second demonstration, we create and study Sn–Na hybrid anodes and show that they can be cycled stably for more than 1,700 hours with minimal voltage divergence. Charge storage at the hybrid anodes is reported to involve a combination of alloying and electrodeposition reactions. Solid-electrolyte interphases (SEI) play important roles in battery operations. Here, the authors report hybrid anodes by forming a Sn overlayer on alkali metal electrodes, leading to a robust SEI and consequently improved electrochemical performance.

Wall paintings from the Jokhang temple, Lhasa, Tibet, China cover over 4000 m2. In order to protect these valuable paintings and to provide more conclusive information regarding the date of the painting scheme from the outer north Gallery, painting materials and techniques have been studied using optical and scanning electron microscopy, X-ray diffraction and raman spectroscopy. Organic materials were analysed with pyrolysis-gas chromatography–mass spectrometry. The wall painting technique is typical of Tibetan paintings and includes multiple layers of locally sourced materials. Analytical results demonstrate the presence of natural and synthetic pigments, including cinnabar (HgS), malachite (CuCO3·Cu(OH)2), azurite (2CuCO3·Cu(OH)2), orpiment (As2S3), red lead (Pb3O4), synthetic ultramarine blue (Na3CaAl3Si3O12S) and emerald green (Cu(C2H3O2)2·3Cu(AsO2)2) which allow us to date the paintings from the mid to late nineteenth century. The binding media is a kind of animal glue which is likely to be bovine or yak glue, the traditional medium used in Tibet. Gilding was applied as gold powder or gold foil. In the past a sealing material or varnish containing drying oil (maybe tung oil) and pine resin was applied to the surface to protect the paintings.

Zinc oxide-based composite nanomaterials were successfully synthesized by a simple sol-gel combined with a hydrothermal synthesis method. X-ray powder diffraction and Fourier transform infrared spectroscopy results confirm that the zinc oxide-based composite nanomaterials only corresponding metal oxides exist in the samples and not contain any other impurities. Scanning electron microscopic images shows that the ZnO/ZnAl2O4 composite materials are composed of fine nanoparticles and rhombic fine particles. Compared with ZnAl2O4 and ZnO, ZnO/ZnAl2O4 composite materials have a wider light absorption capacity, suggesting that the ZnO/ZnAl2O4 composite materials have a high antibacterial activity. Fluorescence spectrum analysis reveals that the ZnO/ZnAl2O4 composite materials have higher charge transfer and separation efficiency in visible light range, indicating that its has high antibacterial activity. Three obvious emission peaks at 372, 420 and 430 nm can be found for the ZnO/ZnAl2O4 composite materials with excitation wavelength of 250 nm. Staphylococcus aureus and Escherichia coli were selected as the representatives of gram-positive and negative bacteria, respectively, and the antimicrobial properties of ZnO/ZnAl2O4 composite materials were evaluated. The ZnO/ZnAl2O4 composite materials exhibits higher photocatalytic inactivation rate than previously reported due to the synergistic effect of mass ratio of ZnO to ZnAl2O4, preparation method, specific surface area, light absorption capacity, charge transfer and separation efficiency. Based on experimental and theoretical analysis, a possible photocatalytic inactivation mechanism of ZnO/ZnAl2O4 composite materials was proposed.

Summary Substrates able to rectify transport of ions based on charge and/or size are ubiquitous in biological systems. Electrolytes and interphases that selectively transport electrochemically active ions are likewise of broad interest in all electrical energy storage technologies. In lithium-ion batteries, electrolytes with single- or near-single-ion conductivity reduce losses caused by ion polarization. In emergent lithium or sodium metal batteries, they maintain high conductivity at the anode and stabilize metal deposition by fundamental mechanisms. We report that 20- to 300-nm-thick, single-ion-conducting membranes deposited at the anode enable electrolytes with the highest combination of cation transference number, ionic conductivity, and electrochemical stability reported. By means of direct visualization we find that single-ion membranes also reduce dendritic deposition of Li in liquids. Galvanostatic measurements further show that the electrolytes facilitate long (3 mAh) recharge of full Li/LiNi 0.8 Co 0.15 Al 0.05 O 2 (NCA) cells with high cathode loadings (3 mAh cm −2 /19.9 mg cm −2 ) and at high current densities (3 mA cm −2 ).

Secondary batteries based on earth-abundant sodium metal anodes are desirable for both stationary and portable electrical energy storage. Room-temperature sodium metal batteries are impractical today because morphological instability during recharge drives rough, dendritic electrodeposition. Chemical instability of liquid electrolytes also leads to premature cell failure as a result of parasitic reactions with the anode. Here we use joint density-functional theoretical analysis to show that the surface diffusion barrier for sodium ion transport is a sensitive function of the chemistry of solid–electrolyte interphase. In particular, we find that a sodium bromide interphase presents an exceptionally low energy barrier to ion transport, comparable to that of metallic magnesium. We evaluate this prediction by means of electrochemical measurements and direct visualization studies. These experiments reveal an approximately three-fold reduction in activation energy for ion transport at a sodium bromide interphase. Direct visualization of sodium electrodeposition confirms large improvements in stability of sodium deposition at sodium bromide-rich interphases., The chemistry at the interface between electrolyte and electrode plays a critical role in determining battery performance. Here, the authors show that a NaBr enriched solid–electrolyte interphase can lower the surface diffusion barrier for sodium ions, enabling stable electrodeposition.

Transition metal phosphides are a new class of materials generating interest as alternative negative electrodes in lithium-ion batteries. However, metal phosphide syntheses remain underdeveloped in terms of simultaneous control over phase composition and 3D nanostructure. Herein, M13 bacteriophage is employed as a biological scaffold to develop 3D nickel phosphide nanofoams with control over a range of phase compositions and structural elements. Virus-templated Ni5P4 nanofoams are then integrated as thin-film negative electrodes in lithium-ion microbatteries, demonstrating a discharge capacity of 677 mAh g⁻¹ (677 mAh cm⁻³) and an 80% capacity retention over more than 100 cycles. This strong electrochemical performance is attributed to the virus-templated, nanostructured morphology, which remains electronically conductive throughout cycling, thereby sidestepping the need for conductive additives. When accounting for the mass of additional binder materials, virus-templated Ni₅P₄ nanofoams demonstrate the highest practical capacity reported thus far for Ni₅P₄ electrodes. Looking forward, this synthesis method is generalizable and can enable precise control over the 3D nanostructure and phase composition in other metal phosphides, such as cobalt and copper. Keywords: 3D nanostructure; transition metal phosphide; biotemplating; M13 bacteriophage; Li-ion microbattery, United States. Defense Advanced Research Projects Agency (Grant HR0011835402), National Science Foundation (Grant DMR‐1419807), Shell International Exploration and Production B.V. (Grant 4550155123)

Ethanamizuril is a new triazine compound that has the potential to be a novel anticoccidial drug. Toxicological studies in experimental rats were performed to understand the safety profile of ethanamizuril for drug product development. In this study, a novel, selective and accurate ultra-performance liquid chromatography tandem mass spectrometry method has been developed for the determination of ethanamizuril concentrations in rat plasma. With 4-nitro-o-cresol as an internal standard, sample pretreatment involved a one-step extraction with acetonitrile of 100 μL plasma. The detection was carried out by electrospray ionization mass spectrometry in negative ion mode with selected ion recording. The standard curves were linear (r2 ≥ 0.999) over the concentration range of 0.1-100 μg/mL. The relative standard deviations of intra- and inter-day precisions were less than 8.4 and 8.87%, respectively. The mean extraction recovery of ethanamizuril from rat plasma was 97.68-102.57%. The method was fully validated and successfully applied to monitor plasma concentrations of ethanamizuril in a short-term toxicity study and two-generation reproduction toxicity study. The result of the study confirmed that the elimination of ethanamizuril in rats is slow.

Calcium oxalate film was prepared by a novel two-step method on the surface of the marble substrate. The seed film was coated by a chemical reaction process, providing a good connection to the marble surface. Meanwhile, calcium oxalate solution was interwoven into the seed film to form a continuous network at room temperature. The x-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis results indicated that the calcium oxalate film prepared by the two-step method showed a more intensive crystallinity degree and homogenous than that by the traditional oxalate treatment method (a scattered seed film). Subsequently, it was found such calcium oxalate film is feasible for preventing the marble substrate from chemical weathering. Furthermore, the change of the chromatic value, water absorption properties and adhesion strength of the marble substrates by the film is minimal. This method overcomes the limitations of traditional oxalate treatment process and has great potential for the protection of marble artifacts.