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The absolute dating of documents is still one of the most important challenges for forensic document examiners (FDE). The potential difference between the date on a questioned document and the actual year of production of the used paper can be only 1 to 5 years. Until now, there was no analytical method with this accuracy available. This study demonstrates a method for an absolute dating of paper by using the 14C bomb peak and dating the starch in the paper. Accelerator mass spectroscopy (AMS) radiocarbon measurements were performed on starch extracts and cellulose fibers from 50 paper samples with known production year from 1950 to 2018. For most of the paper samples, the measured 14C concentration values in the starch extracts were highly correlated with the data of the 14C bomb peak calibration curve. The differences between the calibrated ages and the actual harvest years of the starch‐containing plants were only up to 3 years. The 14C concentration in the paper fibers showed a lower but significant correlation with the production year of the papers and can be used to support the dating results of the starch extracts. In order to secure the accuracy of the dating, aside from the radiocarbon measurements of the extracted starch other analytical methods or data are used, like a detailed chemical analysis of the paper composition including fiber composition and the spectroscopic analysis of the purity of the starch extracts. In practice, only starch extracts without contaminations are used for the paper dating. [ABSTRACT FROM AUTHOR]

Carbon paper has been synthesized by paper making process followed by composite formation, and further chemically oxidized by immersing into a mixture of sulphuric acid and potassium dichromate to be used as an electrode for supercapacitor applications. XRD and Raman spectra were used to analyze the structure, and the defects in the samples respectively, in due course of oxidation. FESEM images revealed the morphology of oxidized samples to be rougher, which contributes towards increased active sites for reaction. The sample (COCP‐60) optimized via electrochemical studies, was further tested in various electrolytes to study the electrode/electrolyte interaction. It delivered a highest areal capacitance of 6.02 F/cm2 (231.5 F/g) in acidic electrolyte at a current density of 5 mA/cm2 (0.19 A/g). This findings were further corroborated by surface and diffusion contribution studies wherein it was found that diffusion is more profound with acidic electrolyte. The supercapacitor device fabricated with COCP‐60 electrode delivered an energy density of 0.41 Wh/cm2 at 2.83 W/cm2 power density with coulombic efficiency of 98 %, and cyclic stability of ∼90 % for over 5000 cycles. [ABSTRACT FROM AUTHOR]

Commercial polypropylene (PP) and polyethylene (PE) films are widely used as separators for lithium‐ion batteries (LIBs). However, owing to the poor thermal stability of PP and PE films, current LIBs suffer from serious safety risks in their practical applications. As an effective path, the design of novel high‐safety composite separators can significantly overcome the safety issues of LIBs. Herein, a universal and cost‐effective strategy is developed to fabricate highly‐thermal‐stable separators via coating natural halloysite nanotubes (HNTs) on both sides of commercial papers or waste newspaper. The resulted separators show superior properties, including thermal stability, heat conduction, wettability, and electrolyte uptake. Compared with commercial PP separators, both HNTs coated A4 paper and waste newspaper composite separators enable better cycling and rate performance for Li/LiFePO4 cells. Even after burning in fire or treating under 180 °C, the composite separators still present a normal structure, and the assembled cell can perform as regular. Furthermore, the nail penetration test of pouch cells illustrates that such separator significantly prevents thermal runaway of LIBs. The inexpensive and environmentally friendly materials with a facile coating process provide a highly‐thermal‐stable separator for commercial LIBs. [ABSTRACT FROM AUTHOR]

Electronic paper (e‐paper) is a reflective display technology with unique advantages, such as bistability, low‐power consumption, and high ambient contrast ratio. These features make e‐paper a promising candidate for future Internet of Things applications. Among different technologies of e‐paper, electrophoretic display (EPD) is the most successful one for commercialization. However, the edge ghosting (also known as the fringing effect) still limits the performance of EPD. Herein, we established a model of particle dynamics of electrophoresis, simulated the edge ghosting of microcapsule EPD, analyzed the edge ghosting effect, and revealed the relationship between thicknesses, dielectric constants of the back binder layer, and the edge ghosting. Two EPD panels with different thicknesses of back binder layer were demonstrated, which verifies the accuracy of this simulation model. With the proposed model, many device mechanisms and product issues can be analyzed and illustrated, which is supposed to guide the researchers in optimizing the device structure design of EPD. [ABSTRACT FROM AUTHOR]

Meta‐aramid paper has been widely used in transformers because of its excellent insulation properties and thermal stability. However, with the rapid development of high‐voltage transformers, higher requirements are placed on the breakdown strength of meta‐aramid paper. In this study, meta‐aramid chopped fibers/polyphenylene sulfide (MACFs/PPS) composite paper was prepared by a combination of wet‐copying and hot‐rolling technology. Then the microscopic morphology, mechanical properties, crystallization behavior, insulation properties, and thermal stability of the MACFs/PPS composite paper were studied and evaluated. The experimental results showed that the breakdown strength of the MACFs/PPS composite paper was as high as 46.46 kV/mm, which was 2.7 times higher than the famous Nomex T410 insulating paper. Meanwhile, the MACFs/PPS composite paper presented good mechanical properties and thermal stability. This paper provides a simple and versatile method for the preparation of meta‐aramid composite paper with high breakdown strength. [ABSTRACT FROM AUTHOR]

The XY model of oil‐paper insulation connects the dielectric properties of oil, paper and oil‐paper system. Its equivalent circuit is the basis of the application of dielectric response technology in the state diagnosis of transformer oil‐paper insulation. To better apply the XY model to the study of the dielectric properties of oil‐paper insulation, the dielectric properties of the coaxial oil‐paper insulation system built in the laboratory, XY model and its equivalent circuits are compared. Then an improved circuit of XY model which can reflect the properties of the oil‐paper insulation more truly is proposed. The results show that there is no difference between the XY model and the coaxial model, and both can well characterize the oil‐paper insulation system. The two equivalent circuits of XY model, "Series to Parallel" circuit and "Parallel to Series" circuit, ignore the current tangential component and the electric field distortion in oil‐paper insulation, respectively, resulting in deviations from the XY model. By introducing a new branch C*XY, the improved circuit can reflect the tangential current and electric field distortion in oil‐paper insulation, which can be completely equivalent to XY model. In addition, there is a characteristic frequency point in the oil‐paper insulation system, where the dielectric loss factor tan δ of oil, paper and oil‐paper system are the same. There is no difference between the XY model and its two equivalent circuits at this point. The characteristic frequency is determined by the dielectric properties of oil and paper, and not affected by the insulation structure. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

BACKGROUND: Deinking is an important part of paper recycling that involves the removal of ink particles from the paper fibres. This industrial process is important so that the fibres can be recirculated back into paper production, which enables better sustainability as fewer fresh fibres are needed. In this study, we examined five different alternative fibre materials from different agricultural residues and industrial processes for the pilot production of papers. Papers containing fibres from invasive plants (Japanese knotweed), dedicated crops (miscanthus, acacia), agricultural residues (tomato stems), and industrial waste (jute - fibres from coffee bags) were printed with water-based flexo inks and deinked with two separate processes (chemical and enzymes). Mechanical (break and tensile index, breaking length) and optical properties (ISO whiteness, brightness and CIE L*a*b* values) were measured and ink elimination IR700 and deinking efficiency was calculated for the two deinking processes. RESULTS: Enzymatic treatment improved the mechanical properties of deinked pulp in comparison with the classic chemical treatment. Mechanical strength for almost all papers increased slightly (breaking length up to 20% in tomato and jute), and the optical result (brightness) increased similarly for both processes due to the bleaching action of the colour-shaded samples, whereas the deinking efficiency showed mixed results between chemical- and enzyme-type deinking (with chemical achieving better elimination measured at 700 nm) in the typical range of ink elimination values (15-35%) for flexographic inks. This indicates further optimization of the deinking with enzymes is needed due to different alternative fibre compositions and variations of residues in the delignification processes. CONCLUSION: Using a combination of adjusted enzymatic treatment as a precursor for deinking of paper-based packaging materials sourced from alternative fibres showed promising results regarding mechanical properties, whereas the optical properties need to be improved with cellulase optimization or by using mixes of different enzymes. These kinds of paper materials printed with flexo inks were found to be successfully deinkable with the chemical ISO-based deinking protocol. [ABSTRACT FROM AUTHOR]

Background: Regulatory aspects of transfusion medicine add complexity in blinded transfusion trials when considering various electronic record keeping software and blood administration processes. The aim of this study is to explore strategies when blinding transfusion components and products in paper and electronic medical records. Methods: Surveys were collected and interviews were conducted for 18 sites across various jurisdictions in North America to determine solutions applied in previous transfusion randomized control trials. Results: Sixteen responses were collected of which 11 had previously participated in a transfusion randomized control trial. Various solutions were reported which were specific to the laboratory information system (LIS) and electronic medical record (EMR) combinations although solutions could be grouped into four categories which included the creation of a study product code in the LIS, preventing the transmission of data from the LIS to the EMR, utilizing specialized stickers and labels to conceal product containers and documents in the paper records, and modified bedside procedures and documentation. Discussion: LIS and EMR combinations varied across sites, so it was not possible to determine combination‐specific solutions. The study was able to highlight solutions that may be emphasized in future iterations of LIS and EMR software as well as procedural changes that may minimize the risk of unblinding. [ABSTRACT FROM AUTHOR]

Key points: Academia is already witnessing the abuse of authorship in papers with text generated by large language models (LLMs) such as ChatGPT.LLM‐generated text is testing the limits of publishing ethics as we traditionally know it.We alert the community to imminent risks of LLM technologies, like ChatGPT, for amplifying the predatory publishing 'industry'.The abuse of ChatGPT for the paper mill industry cannot be over‐emphasized.Detection of LLM‐generated text is the responsibility of editors and journals/publishers. [ABSTRACT FROM AUTHOR]