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Ultra high frequency (UHF) partial discharge (PD) detection is a common method for transformer oil-paper insulation defect location. However, the accuracy of PD positioning in practical application is easily affected by noise and sensor layout. In order to ensure the effectiveness of PD positioning detection of transformer oil-paper insulation defect, an UHF PD positioning detection platform for oil-paper insulation defects is established. Based on the conventional K-means method, a modified clustering demarcation PD anti-interference positioning method is proposed, which effectively reduces the positioning error. Aiming at the problem of sample clustering demarcation aliasing, when the optimal correction coefficient L is 1.1, the UHF PD positioning error can be reduced to less than 0.1 m, which verifies the effectiveness of the proposed method. Finally, the variation law of positioning error of different sensor layout is analyzed, and the optimal layout scheme of UHF sensor for transformer oil-paper insulation defect detection is proposed, which can provide reference for the layout and positioning of transformer on-line monitoring sensor.

A new method was proposed for point-of-care testing (POCT) of immunosuppressants in blood using thin-layer paper spray ionization and a miniature mass spectrometer. The aluminum thin-layer plate was used as paper spray substrate, and cut into an equilateral triangle. Aliquots of 10 μL blood sample were loaded on the aluminum thin-layer plate, and then 20 μL methanol was dropped as elution/spray solvent. The tip of the triangular plate was placed 1.0 cm in front of the discontinuous atmospheric pressure interface (DAPI) of the miniature mass spectrometer. When the spray voltage was applied, the sample was eluted from the triangular plate and formed paper spray ionization at the tip. Coupled with the miniature mass spectrometer, five immunosuppressants were detected under negative ion mode. The precursor ions ［M-H］- of tacrolimus, sirolimus, everolimus, ciclosporin A, and mycophenolic acid are m/z 802.6, 912.6, 957.1, 1 200.8, 319.1, and product ions are m/z 560.2 and 604.3, m/z 590.3 and 321.2, m/z 590.3 and 365.2, m/z 1 088.8, m/z 287.4 and 275.1, respectively. Based on the observed signal-to-noise ratio (S/N) of the most intense tandem mass spectrometry (MS/MS) fragment peaks and using the S/N=3 and 10 as the criteria, the limits of detection (LODs) and quantitation (LOQs) are estimated to be 0.5-5 mg/L and 1-10 mg/L, respectively. The internal standard method was used for quantitative analysis, and indapamide was used as the internal standard compound. Sufficient linearity for each analyte is obtained with the correlation coefficients (r) greater than 0.99. The proposed method displays good recoveries in the range of 91.0%-114.3% with the relative standard deviations (RSDs) less than 8.4%. Moreover, the developed method was used for the analysis of blood samples, which spiked with tacrolimus, sirolimus, everolimus, cyclosporine A and mycophenolic acid at the concentration of 100 mg/L. The analytical results demonstrated the consistency between the proposed method and the traditional liquid chromatography-mass spectrometry (LC-MS) method. The entire analysis procedure can be completed within 1 min. The proposed method is simple, fast, accurate, efficient, and suitable for POCT of immunosuppressants in blood.

Based on the selective quenching effect of the flavonoid rutin on the fluorescence of carbon dots prepared by asparagine pyrolysis, a method for rapid detection of rutin content in the flower buds of Sophora japonica by using chitosan-based carbon dot paper chip was developed. A filter paper was immersed in the casting solution of carbon dots and chitosan. After drying, a carbon dot chitosan film was formed on the surface of the filter paper, so that the chitosan-based carbon dot paper chip was obtained. After samples were dripped on the chip, chromogenic reaction occurred uniformly within a limited region, and pictures were taken under an ultraviolet (UV) lamp at 365 nm for analysis of the red (R), green (G), and blue (B) values of the colored spots in order to optimize the preparation conditions and detection conditions. The results showed that the optimal conditions were as follows: chitosan concentration of 20 mg/mL, carbon spot concentration of 1.0 mg/mL, 50% ethanol as sample solvent, and reaction time of 20 min. Under these conditions, the difference (ΔG) in G-value between sample and solvent spots had a linear relationship with rutin concentration (C) in the range of 4 to 120 mg/mL. Using this method, the average contents of rutin in the flower buds of S. japonica from three batches were determined to be 23.85%, 22.83% and 20.30%, the average relative standard deviations (RSDs) were 6.1%, 5.6% and 6.7%, and the recoveries were 91.27% to 107.5%, which were close to the results of high performance liquid chromatography (HPLC). The proposed method is simple and rapid, and can be used for rapid on-site determination of rutin content in the flower buds of S. japonica.

Copyright of China Journal of Oral & Maxillofacial Surgery is the property of Shanghai Jiao Tong University, College of Stomatology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Capital Institute of Physical Education is the property of Shoudu Tiyu Xueyuan and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Results of academic research require publication and need to be reviewed by peers before they can contribute to the existing body of knowledge. Among the various means of publishing research findings, researchers may, according to past academic practices, first present their research results in conferences, seminars or symposiums, and then submit their results to journals for publication. Hence, the issue of “extended publication”, where conference papers are revised and submitted to journals, has gained attention in the library and information science community. This study collected public documents on the Internet and applied document analysis to examine the ethical considerations regarding such extension practice. First, this research reviewed the basic principles of research integrity and responsible behavior. Secondly, this research listed several types of violation related to research paper writing and submission, and studied the guidelines established by both domestic and foreign academic organizations, publishers, and journals. The findings of the research were used to provide specific recommendations on the best practices for extending conference papers to journal articles.

To explore the microscopic mechanism of thermal stability of oil-paper insulation， a molecular model consistent with the actual oil-paper insulation is established. Through comparison with the experimental results， the effectiveness of the model is verified. With temperature as an independent variable， variation of the mechanical parameters and hydrogen bond energy of the cellulose molecular model under the action of a thermal field is investigated. The results show that parameters characterizing the mechanical properties of cellulose， such as bulk modulus （K）， Young's modulus （E）， shear modulus （G）， and Poisson's ratio （v） of the cellulose crystalline zone model are larger than those of the amorphous zone model at the same temperature， and the distribution of hydrogen bond energy remains the same. Thus， the cellulose crystalline zone is superior to the amorphous zone in mechanical properties and determines the insulation properties of cellulose insulating paper. The results of the study provide a theoretical basis and method for investigating the microscopic mechanism of thermal aging of oil-paper insulation.

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The insulation performance of transformer bushings is a crucial aspect that directly affects the safe operation of equipment. To diagnose the insulation status of transformer bushings and mitigate the impact of small-sample imbalanced data on diagnostic results, a particle swarm optimization combined with back propagation neural network (PSO-BPNN) and adaptive synthetic sampling (ADASYN) method are employed to fault diagnosis of transformer bushing. Initially, historical fault data of transformer bushings are gathered, and a sample set of dissolved gases in transformer oil with distinct fault categories is established. The ADASYN algorithm is used to synthesize the minority class samples in the original data, which allowed for obtaining balanced fault data. The balanced dissolved gases in oil served as the model input, and the fault status is used as the label output to diagnose the transformer bushings using the PSO-BPNN model. To diagnose the bushings under the original sample set, the back propagation neural network (BPNN), genetic combined with back propagation neural network (G-BPNN), cuckoo search combined with back propagation neural network (CS-BPNN), and PSO-BPNN models are used. The results reveal that the PSO-BPNN model based on ADASYN balanced data exhibited the highest accuracy among the various models for fault diagnosing the insulation status of transformer bushings. This approach effectively mitigate the impact of small sample imbalanced data on diagnostic results, and provide an effective method for assessing the insulation performance of transformer bushings.

“Lab on paper” is a paper-based microanalytical system with unique advantages such as high sensitivity, low cost, portability, and mass production, which breaks through the limitations of traditional detection technologies and shows great potential in the field of rapid on-site food detection. In this paper, the typical “labs on paper”, including chromatographic paper, chemical test chip, lateral flow assay (LFA), microfluidic paper-based analytical devices (μPADs), and synthetic biological paper, are systematically reviewed. Special emphasis is put on the application of “lab on paper” in the field of food detection. Finally, the advantages, challenges, and future prospects of paper-based analytic methods are discussed, which may provide theoretical support for better application of “lab on paper” in the field of food detection.

[Purpose/Significance] Interdisciplinary research can creatively solve complex problems in natural environment and human society through knowledge integration and penetration. With the increase of interdisciplinary research results, the evaluation of interdisciplinarity becomes increasingly necessary. How to establish an effective method for interdisciplinarity measurement and achieve a comprehensive measurement of scientific research papers is an urgent problem to be solved. [Method/Process] Based on the above background, this study takes the data of scientific research papers as the analysis source, deconstructs the interdisciplinarity of scientific research papers from multiple dimensions, constructs the feature set of interdisciplinarity of scientific research papers, and on this basis proposes the method for measuring interdisciplinarity based on the adaptive method of machine learning, and conducts a comprehensive measurement of interdisciplinarity. This study has certain positive significance for researchers to understand the interdisciplinary papers in the field. The work process is as follows: First of all, the basic concepts of interdisciplinarity are sorted out and related concepts are discriminated, and the index of interdisciplinarity of different dimensions is analyzed. Based on the connotation and characteristics of interdisciplinary research, the characteristic index of interdisciplinarity of scientific research papers is extracted from three dimensions: subject attribute, knowledge network topology and knowledge integration text content. Secondly, an interdisciplinarity measurement method based on machine learning is constructed. By analyzing information gain and feature similarity of input indexes and data in feature sets, a feature selection calculation method based on adaptive feature selection is proposed, and the accuracy of feature classification is maximized by machine learning classifier. At the same time, the feature subset that can best express the interdisciplinary is selected based on the adaptive selection of the minimum number of features, and the selected adaptive feature set is used in the calculation of the interdisciplinary of the paper, and the results of the calculation of the original feature set are analyzed comprehensively. Finally, an empirical study was carried out in the field of plant nanobiotechnology to verify the effectiveness of the index system and adaptive feature selection listed above, identify and screen papers with high interdisciplinarity in the field, measure the interdisciplinarity of papers and identify key influencing factors based on the calculation of subject attributes, knowledge network topology and knowledge integration text content features. [Results/Conclusions] The main empirical results show that, among the subject attributes, the balance degree and the difference degree have a greater effect on the interdisciplinary evaluation. The overall effect of knowledge network topology structure features is satisfactory, the distribution breadth of knowledge integration text content features has a greater effect on interdisciplinary evaluation, and the calculation effect is further improved by fitness weighted summation of each feature. The results demonstrate that the adaptive feature selection proposed in this paper can effectively screen the interdisciplinary related feature indexes, improve the reliability of the results, and achieve a comprehensive and in-depth measurement of the interdisciplinary of scientific research papers. This measure method avoids the subjective defects that may occur in qualitative evaluation and the problems that different measure indicators may produce contradictory results. It provides a new idea and direction for interdisciplinary measurement.

New paper-based microfluidic technology has been widely used in many fields due to their advantages such as easy preparation, low cost, and non-toxic environmental protection, compared with the shortcomings of other food analysis and detection techniques such as complex production method and high cost of preparation. The outline of new paper-based microfluidic technology is briefly summarized and the probes including organic molecules, nanomaterials and polymers their structural activity with regard to sensing performances along with their limit of detection are also discussed. This review is expected to assist readers for better understanding of the sensing mechanisms of various chemo and bio-probes utilized in µPADs, as well as promote their advancement in the field. The detection mechanism and its advantages in the whole detection system at the same time to get the ideal experimental results of new paper-based microfluidic technology in the food analysis of pesticide residues, pathogenic bacteria, additives, heavy metals and other substances are mainly introduced. This study would provide the theoretical basis and references for fast detection field. The future challenges and application prospects of this technology are prospected.

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fruit paper is a paper-shaped snack made from fresh fruit after pulping, boiling and drying. Drying, one of the oldest methods for food preservation, removes water from fruit and extends its shelf-life for year-round consumption. The most commonly used drying methods include hot air drying, vacuum drying, freeze drying, and their combinations. The energy efficiency of drying process and the quality of fruit paper are both important to be considered in fruit pulp drying. This article updates the research status of drying technologies applied in fruit paper production, including hot air drying, freeze drying, vacuum drying, microwave drying, infrared radiation drying, and refraction window drying. In addition, the influence of the pretreatments and drying process on fruit paper's shape, texture, and nutrients are also summarized. This work aims to improve the drying efficiency of fruit paper and retain the active ingredients of fruit to the maximum extent, and to provide reference for further research on drying processing of fruit paper in food industry.

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Three kinds of commercial ink-jet printing paper were taken as the research objects, which were represented by sample A, sample B and sample C respectively. Sample A and sample C were domestic products Abbott and Jiayi, and sample B was foreign product Gulou. The structure and composition of the three sample coatings were determined, and the surface properties of the three coatings were analyzed. This helps to understand the performance status of inkjet paper products on the market, and has guiding significance for the study of various factors affecting the performance of inkjet paper coatings. AFM and SEM were used to observe the surface morphology of the three samples. It was found that the coating pigment particles of sample A and sample B had good dispersion uniformity, and the coating pigment particles of sample C aggregated and the dispersion uniformity was poor. The results of cross-section SEM and EDS analysis show that only sample B coating has a double-layer structure, in which the bottom layer is aluminum-based pigment and silicon-based pigment, and the surface layer is only aluminum-based pigment. The coatings of sample A and sample C are single-layer aluminum-based materials. The properties of the coating surface of the three samples were analyzed. The results showed that the basic properties of the three samples met the product quality standards. Among them, the coating of sample B had the highest gloss (74.30%), hardness (3H) and water resistance. In terms of ink absorption, the ink absorption of sample B coating (64.7%) was higher than that of sample C (57.9%), slightly lower than that of sample A (69.2%). Sample B had the best comprehensive performance among the three samples. Finally, a double-layer coating process scheme for improving the performance of inkjet printing paper is proposed, which provides a direction for improving the performance of inkjet printing paper and has practical significance for the research of advanced inkjet printing paper. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)