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BACKGROUND With the wide application of iridium and rhodium in aerospace, electronics, energy and other fields, it has become a very attractive metal in the world. In China, iridium and rhodium ore resources are relatively scarce with low grade, so it is essential to recover iridium and rhodium from secondary mineral resources. Copper anode slime enriches most of the precious metals such as iridium and rhodium in ores, which has high comprehensive recovery value. At present, there is no detection standard for iridium and rhodium in copper anode slime. The migration behavior of iridium and rhodium was not clear, so it was difficult to achieve directional enrichment and efficient extraction of iridium and rhodium metals. Therefore, the development of detection methods for iridium and rhodium in copper anode slime is an important prerequisite for the recovery and extraction of iridium and rhodium. OBJECTIVES An analytical method for accurate determination of iridium and rhodium in copper anode slime was established to maximize the utilization of mineral resources and the recycling rate of iridium, rhodium and other precious metals. At the same time, it could provide data support for the purification of iridium and rhodium in copper anode slime. METHODS In this paper, a method for determination of iridium and rhodium in copper anode slime by inductively coupled plasma-mass spectrometry (ICP-MS) with nickel sulphide fire assay was established. In the experiment, the precious metals iridium and rhodium in the sample were captured by nickel sulphide fire assay. The NiS beads were dissolved with 50% hydrochloric acid so that the precipitation of rhodium and iridium was separated from silver and other impurity elements through filtration when it was hot. The precipitates containing iridium and rhodium were effectively separated from silver and other impurity elements. The precipitate of iridium and rhodium with filter film were transferred into a closed digestion tank and dissolved in 50% aqua regia. The contents of iridium and rhodium in the solution were directly determined by ICP-MS. RESULTS The conditions such as the ingredient of nickel sulphide fire assay, the concentration of hydrochloric acid, tellurium coprecipitation, the sealing digestion time and temperature were studied. The experimental results showed that the molten slag was acidic when the ratio of nickel to sulfur was 4∶1, and it could effectively capture the iridium and rhodium in the sample with good fluidity of molten slag and the separation effect of slag buckle. When the NiS beads were dissolved by 50% hydrochloric acid, the dissolution reaction of NiS beads was suitable and complete. The precipitation containing rhodium and iridium was separated from impurity elements and filtered when hot. The precipitation was sealed and digested by dilute aqua regia (1∶1) at 160℃ for 2-3h. The possible MS interference was eliminated by selecting a suitable determination isotope. The 185Re was selected as the internal standard of 103Rh and 203Tl as the internal standard of 193Ir to eliminate the effect of signal drift, the results of iridium and rhodium had high precision and accuracy. The standard solution series of iridium and rhodium were determined under the optimized experimental conditions. The results indicated that the mass concentration of iridium and rhodium in the range of 10-100μg/L were linear to the ratio of the intensity of iridium and rhodium to the internal standard mass spectrometry. The calibration curves of iridium and rhodium were y=36674.6x+8264.7 and y=45686.7x+288.6, respectively, and the linear correlation coefficient (r) of calibration curves of iridium and rhodium were more than 0.999. The detection limits for iridium and rhodium were 0.007μg/L and 0.011μg/L, respectively, and the lower limits of detection were 0.024μg/L and 0.038μg/L, respectively. The content results of rhodium and iridium in 8 actual samples with the method showed that, the relative standard deviation (RSD, n=7) was between 1.40% and 4.57%, and the recovery was in the range of 95.00% to 103.65%. CONCLUSIONS The method has high efficiency and accuracy and can meet the detection requirements of copper anode slime samples.

Video encoding technology is a foundational component in the advancement of modern technological applications. The latest standard in universal video coding, H.266/VVC, features a quad-tree with nested multi-type tree (QTMT) partitioning structure, which represents an improvement over its predecessor, High-Efficiency Video Coding (H.265/HEVC). This configuration facilitates adaptable block segmentation, albeit at the cost of heightened encoding complexity. In view of the aforementioned considerations, this paper puts forth a deep learning-based approach to facilitate CU partitioning, with the aim of supplanting the intricate CU partitioning process observed in the Versatile Video Coding Test Model (VTM). We begin by presenting the Gradient Feedback Hierarchical CNN (GFH-CNN) model, an advanced convolutional neural network derived from the ResNet architecture, enabling the extraction of features from 64 × 64 coding unit (CU) blocks. Following this, a hierarchical network diagram (HND) is crafted to depict the delineation of partition boundaries corresponding to the various levels of the CU block's layered structure. This diagram maps the features extracted by the GFH-CNN model to the partitioning at each level and boundary. In conclusion, a LightGBM-based decision tree classification model (L-DT) is constructed to predict the corresponding partition structure based on the prediction vector output from the GFH-CNN model. Subsequently, any errors in the partitioning results are corrected in accordance with the encoding constraints specified by the VTM, which ultimately determines the final CU block partitioning. The experimental results demonstrate that, in comparison with VTM-10.0, the proposed algorithm achieves a 48.14% reduction in complexity with only a 0.83% increase in bitrate under the top-three configuration, which is negligible. In comparison, the top-two configuration resulted in a higher complexity reduction of 63.78%, although this was accompanied by a 2.08% increase in bitrate. These results demonstrate that, in comparison to existing solutions, our approach provides an optimal balance between encoding efficiency and computational complexity. [ABSTRACT FROM AUTHOR]

Background: Although there are many benign tumors in the ovarian adnexal area, the four most common types are still luteal cyst, ovarian mature cystic teratoma (OMCT), ovarian endometriosis, and benign epithelial tumors of the ovary. Purpose: This study aimed to examine the correlation between six tumor markers (CEA, AFP, CA125, CA19-9, SCC, HE4) in the differential diagnosis of female adnexal benign masses and assess their diagnostic value. Patients and Methods: In this study, 135 patients with adnexal benign masses were treated in Zhengzhou first people's Hospital from January 2018 to January 2023. 135 patients were divided into four groups: luteal cyst (13.3%), OMCT (42.2%), ovarian endometriosis (23.7%) and benign epithelial tumors of the ovary (including mucinous cystadenoma and serous cystadenoma) in group D. The receiver-operating characteristic (ROC) curve was used to assess the diagnostic value of each marker and combined detection. Results: The diameter of luteal cysts was significantly smaller than that of benign ovarian tumors (p < 0.001). ROC analysis showed that the combination of AFP, CA125, CA19-9, and SCC had a higher diagnostic rate for luteal cysts (AUC=0.871; sensitivity: 71.8%; specificity: 88.9). The SCC level in OMCT was significantly higher than in other benign ovarian tumors (p=0.007). ROC analysis indicated that the combination of AFP, HE4, and SCC had a higher diagnostic rate for OMCT (AUC=0.753; sensitivity: 65.4%; specificity: 75.4%). The CA125 level in ovarian endometriosis was significantly higher than in other accessory benign tumors (p < 0.001). ROC analysis demonstrated that the combination of AFP, CA125, and CA19-9 had a higher diagnostic rate for ovarian endometriosis (AUC=0.935; sensitivity: 76.7%; specificity: 96.9%). The tumor diameter of benign epithelial tumors of the ovary was significantly larger than that of other benign ovarian tumors (p < 0.001). ROC analysis revealed that the combination of CA125 and CA19-9 had a higher diagnostic rate for benign epithelial tumors of the ovary (AUC=0.792; sensitivity: 64.5%; specificity: 85.7%). Conclusion: The findings of this study demonstrate that the combined use of tumor markers (CEA, AFP, CA125, CA19-9, SCC, and HE4) has value in diagnosing benign ovarian tumors, including luteal cysts, OMCT, ovarian endometriosis, and benign epithelial tumors of the ovary. However, it is important to acknowledge the limitations of this study, which include its single-center nature and the small sample size. Despite these limitations, the results highlight the potential utility of these markers in clinical practice. [ABSTRACT FROM AUTHOR]

The contrastive vision–language pre-trained model CLIP, driven by large-scale open-vocabulary image–text pairs, has recently demonstrated remarkable zero-shot generalization capabilities in diverse downstream image tasks, which has made numerous models dominated by the "image pre-training followed by fine-tuning" paradigm exhibit promising results on standard video benchmarks. However, as models scale up, full fine-tuning adaptive strategy for specific tasks becomes difficult in terms of training and storage. In this work, we propose a novel method that adapts CLIP to the video domain for efficient recognition without destroying the original pre-trained parameters. Specifically, we introduce temporal prompts to realize the object of reasoning about the dynamic content of videos for pre-trained models that lack temporal cues. Then, by replacing the direct learning style of prompt vectors with a lightweight reparameterization encoder, the model can be adapted to domain-specific adjustment to learn more generalizable representations. Furthermore, we predefine a Chinese label dictionary to enhance video representation by co-supervision of Chinese and English semantics. Extensive experiments on video action recognition benchmarks show that our method achieves competitive or even better performance than most existing methods with fewer trainable parameters in both general and few-shot recognition scenarios. [ABSTRACT FROM AUTHOR]

Existing research on multimodal machine translation (MMT) has typically enhanced bilingual translation by introducing additional alignment visual information. However, picture form requirements in multimodal datasets pose important constraints on the development of MMT because this requires a form of alignment between image, source text, and target text. This limitation is especially compounded by the fact that the inference phase, when aligning images, is not directly available in a conventional neural machine translation (NMT) setup. Therefore, we propose an innovative MMT framework called the DSKP-MMT model, which supports machine translation by enhancing knowledge distillation and feature refinement methods in the absence of images. Our model first generates multimodal features from the source text. Then, the purified features are obtained through the multimodal feature generator and knowledge distillation module. The features generated through image feature enhancement are subsequently further purified. Finally, the image–text fusion features are generated as input in the transformer-based machine translation reasoning task. In the Multi30K dataset test, the DSKP-MMT model has achieved a BLEU of 40.42 and a METEOR of 58.15, showing its ability to improve translation effectiveness and facilitating utterance communication. [ABSTRACT FROM AUTHOR]

We explore theoretically Goos-Hänchen (GH) shift around the defect mode in superconducting defective photonic crystals (PCs) in cryogenic environment. The defective PCs are constructed by alternating semiconductors and superconductors. A defect mode arises in the photonic bandgap and sensitively depends on environment temperature and hydrostatic pressure. Reflection and transmission coefficient phases make an abruptly jump at the defect mode and giant GH shifts have been achieved around this mode. The maximum GH shift can get as high as 103λ (incident wavelength), which could be modulated by the values of temperature and hydrostatic pressure. This study may be utilized for pressure- or temperature-sensors in cryogenic environment. [ABSTRACT FROM AUTHOR]

We explore theoretically Goos-Hänchen (GH) shift around the defect mode in superconducting defective photonic crystals (PCs) in cryogenic environment. The defective PCs are constructed by alternating semiconductors and superconductors. A defect mode arises in the photonic bandgap and sensitively depends on environment temperature and hydrostatic pressure. Reflection and transmission coefficient phases make an abruptly jump at the defect mode and giant GH shifts have been achieved around this mode. The maximum GH shift can get as high as 103λ (incident wavelength), which could be modulated by the values of temperature and hydrostatic pressure. This study may be utilized for pressure- or temperature-sensors in cryogenic environment. [ABSTRACT FROM AUTHOR]

High‐performance thin film transistors with a remarkable mobility of 38.7 cm2/Vs and excellent stability are demonstrated using amorphous indium zinc oxide (IZO)/indium gallium zinc oxide (IGZO) bilayer film as the active layer. The optimal performance of the bilayer device is found to be contingent upon the critical balance of oxygen flow ratio during sputtering IZO film. The mechanism governing the oxygen‐tuned performance has been thoroughly investigated. A 31‐inch ink‐jet printed AMOLED display panel has been successfully fabricated, with the GOA circuit integrated using this high mobility transistors. The good display performance showcases the significant application potential of the IZO/IGZO bilayer device. [ABSTRACT FROM AUTHOR]

Crude tellurium dioxide is an important raw material for tellurium refining or tellurium chemical production, in which the accurate determination of coexisting elements copper, lead, arsenic, antimony, bismuth and selenium is of great significance for production process quality control and trade settlement. However, there is no standard analytical method for the determination of copper, lead, arsenic, antimony, bismuth and selenium in crude tellurium dioxide. The samples were decomposed by aqua regia and saturated ammonium hydrogen fluoride. Cu 327. 393 nm, Pb 220. 353 nm, Sb 217. 582 nm, Bi 223. 061 nm, As 193.696 nm and Se 196.026 nm were selected as analytical lines. The contents of copper, lead, antimony, bismuth, arsenic and selenium in crude tellurium dioxide were determined by inductively coupled plasma atonic emission spectrometry (ICP-AES) in the medium of aqua regia and tartaric acid. The correlation coefficients of the calibration curves of elements were all higher than 0. 999. The limits of detection of copper, lead, antimony, bismuth, arsenic and selenium were 0.0004%, 0.0005%, 0.0006%, 0. 0007%, 0.0004% and 0.0007%, respectively. The limits of quantification were 0.0012%, 0.0016%, 0.0020%, 0.0025%, 0.0013% and 0.0025%, respectively. The contents of copper, lead, antimony, bismuth, arsenic and selenium in live crude tellurium dioxide samples were determined according to the proposed method. The relative standard deviations (RSD, n = 7) of the results were between 0. 79% and 4. 8%, and the recoveries were between 96. 0% and 103%. The method is simple with high precision and accuracy, which can be used as a method of determination copper, lead, arsenic, antimony, bismuth and selenium in crude tellurium dioxide. [ABSTRACT FROM AUTHOR]

The excessive intake of sucrose in daily life has posed a serious risk to our health. To reduce the consumption of sugars by decreasing the direct addition of sucrose to foods, an alternative substance with low or non-caloric while possessing sweet taste, called sweetener, is needed. As a natural sweetener, erythritol has attracted much attention in past years due to its distinct characteristics, including low- caloric,providing no energy to the body, high stability, and without causing intestine disorders. At present, erythritol has been widely used in foods, medicines, chemical and industrial products, and its market around the world is still growing, which challenges the scale of industrial erythritol production. For this reason, we discuss here the recent advances in the production of erythritol by microorganisms, including the main species used in erythritol production as well as the strain breeding strategies, the biosynthesis of erythritol using renewable resources as the substrate, and metabolic engineering of the strains for enhanced production of erythritol, which aims to provide novel clues for the breeding of species with increased yield of erythritol and the sustainable production of erythritol in the future. [ABSTRACT FROM AUTHOR]