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To study the flow and heat transfer characteristics of diesel particulate filter wall porous media, Lattice Boltzmann Method (LBM) is used to simulate and analyze different structures in this article. On studying the heat transfer and flow characteristics of regular structures such as parallel and staggered structures, it is proved that the distribution of porous media structure has an effect on the heat transfer and flow characteristics. The effects of different structure distributions on the flow and heat transfer characteristics are analyzed by studying the complex structures such as random structure and the structure of Quartet Structure Generation Set (QSGS). The influences of different fiber diameters on the parameters under the parallel arrangement, the staggered arrangement, and the random arrangement is considered. The flow and heat transfer characteristics of the QSGS structure and Sierpinski carpets structure are also considered. Under the same porosity, different fiber diameters have effect on dimensionless permeability coefficient, pressure gradient, and filtration efficiency. The different structures of porous media affect the temperature and pressure distribution. For the relatively complex structure, the flow resistance is greater. The increase in Re will reduce the temperature gradient, and with the increase in Re, the flow in the structure will be more uniform.

Ionic liquids (ILs) are promising solvents for separating aromatics from fuel oils. However, studies for separate polycyclic aromatics with ILs are rare and insufficient, and the impact of solute structure on extraction performance still needs to be determined. In this work, we use 1‐ethyl‐3‐methylimidazolium bis([trifluoromethyl]sulfonyl)imide ([EMIM][NTF2]) as an extractant to separate 1‐methylnaphthalene, quinoline, and benzothiophene from dodecane mixtures. Liquid–liquid equilibrium experiments identified the optimal operating conditions. Nine solute molecules, including five alkanes and four aromatic hydrocarbons, were used to study the relationship between extraction performance and solute structure. Molecular dynamics simulation and quantum chemistry calculations gave a deep insight and reasonable interpretation of the structure‐performance relationship at the molecular level. An industrial‐scale extraction process was proposed. The IL can be easily regenerated using heptane as a back‐extractive solvent. A high‐purity fuel oil with aromatic content below 0.5 wt% is obtained after 8‐stage extraction. [ABSTRACT FROM AUTHOR]

A process of simultaneous desulfurization and dehydration of flue gas with ionic liquid was explored. The selection of ionic liquid was completed based on COSMO‐SAC model. Random forest (RF) and one‐dimensional convolutional neural network were trained for the prediction of CO2 and SO2 solubility. A feature selection method is designed to remove verbose descriptors. The feature importance was analyzed by SHAP analysis. Quantum chemistry calculation and molecular dynamics (MD) simulation were used to investigate the type and position of intermolecular forces. The results show that the R2 coefficients of the two prediction models for CO2 and SO2 test sets reach 0.981 and 0.983. [EMIM][SCN] was selected as the optimal solvent, and the interaction with SO2 is mainly electrostatic and orbital interaction, while the interaction with H2O is strong hydrogen bond. [ABSTRACT FROM AUTHOR]

The impressive electrochemical performance of sodium‐ion batteries at low temperatures has long been recognized as a promising technical advantage. However, the inadequate transport kinetics of Na+ ions and complex interfacial reactions at the hard carbon anode surface hinder the practical implementation of commercial sodium‐ion batteries. Herein, a novel approach to address this issue by introducing a homogenized functional carbon coating layer with a locally curved configuration is proposed. This coating layer is designed to accommodate single CoN4 sites on the surface of commercial hard carbon particles, resulting in enhanced sodium storage performance at low temperatures. The surface‐modified hard carbon anode material (HC‐Z1) demonstrates a commendable rate performance of 220.6 mAh g−1 at 3 A g−1@25 °C and a substantial reversible capacity of 288.7 mAh g−1 with an 89% capacity retention at 0.06 A g−1@‐20 °C. Furthermore, even at a temperature as low as −40 °C, the reversible capacity remains at 270 mAh g−1 at 0.06 A g−1. Extensive characterizations and theoretical calculations provide evidence that the optimized interface between the electrode and electrolyte effectively enhances the desolvation and migration of Na+ ions, particularly at low temperatures. [ABSTRACT FROM AUTHOR]

The production of acetylene (C2H2) via calcium carbide method is an industrial process commonly used in the production of polyvinyl chloride resin. The dehydration of C2H2 is one crucial aspect. In this work, a novel approach based on ionic liquid (IL) separation was explored. Thermodynamic properties of the IL were predicted using the COSMO‐SAC model to screen for an appropriate absorbent. The loss of C2H2 and dehydration performance of IL during dehydration were measured by solubility experiment and laboratory‐scale absorption experiment. Quantum chemistry (QC) calculations and molecular dynamics (MD) simulations were utilized to explore the mechanism of the C2H2 dehydration process. [EMIM][Tf2N] was selected as the final absorbent to achieve highly selective dehydration with low C2H2 losses. Anions play a leading role in the dehydration process, and the dehydration effect mainly depends on hydrogen bonds. This work provides guidance for the rational design of a new absorbent for C2H2. [ABSTRACT FROM AUTHOR]

The grouting quality of prestressed pipelines directly affects the safety and durability of prestressed reinforced concrete bridge structures, attracting wide attention from the engineering community. Based on the principles of the scattering wave method, this paper designs and manufactures a large-scale model to simulate the actual construction testing environment. Several sets of design defects with significantly distributed spans in the prestressing ducts were pre-set, and the Engineering Geophysical Instrument System–Pipeline Grouting Profile (EGS-PGP) equipment developed was used to detect the grouting quality of the prestressed pipelines under different conditions, obtaining the frequency attenuation values at defect locations. The study shows that stability of the peak frequency throughout the test can indicate compact grouting, while a large fluctuation in the peak frequency range with no regular changes can indicate non-compact grouting; a sudden increase or decrease in peak frequency can effectively indicate the location of grouting defects along the pipeline. The number of sudden changes in frequency can indicate the number of gaps inside the pipeline. The chirp signal, compared to the hammer impact signal, shows greater stability and engineering application value in detecting defects using the scatter wave method. This study provides technical support for the detection of grouting quality in prestressed pipelines based on chirp signals. [ABSTRACT FROM AUTHOR]

The quality of grouting in pre-stressed pipelines plays a critical role in ensuring the safety and durability of pre-stressed concrete bridges. In this study, the transmission wave method was proposed as a means to assess the quality of grouting in pre-stressed pipelines. The ABAQUS finite element simulation (FE simulation) method was used to study the propagation of hammer stress waves in pre-stressed pipes. A full-scale test was conducted to verify the numerical simulation using the AGI-BWG instrument system developed to detect the quality of grouting. The results show that the propagation speed of transmitted waves increases and the frequency shifts towards higher frequencies with an increase in void length within pre-stressed pipelines. This research suggests that the propagation velocity of elastic waves in pre-stressed pipelines serves as a key indicator of grouting quality. The transmission wave method, based on hammer signals, proves to be an effective tool for detecting the quality of grouting in pre-stressed pipelines. [ABSTRACT FROM AUTHOR]

Under the pressures of environmental pollution, solar energy and hydrogen have attracted widespread attention, thus promoting the development of photovoltaic–hydrogen integrated energy system. However, multiple uncertainties seriously interfere with the system's economic and stable operation. Therefore, this article proposes a temporal covariance‐involved distributionally robust optimization model for system scheduling considering multiple uncertainties from source, load sides, and market. First, the possible range of the uncertainties distribution is described by a novel moment‐based ambiguity set modified with temporal covariances. Second, the objective function is constructed as a min{sup} form to minimize the expected operation cost under the "worst‐case" distribution in the ambiguity set. Then, the constraints present a two‐stage structure. The first stage guarantees the operation feasibility under the forecasting scenario, and the second stage accounts for forecasting errors to formulate the rescheduling space for resisting uncertainties. Finally, the model is transformed into an easy‐to‐solve semidefinite programming. Simulation finds that the model 1) significantly reduces the average and standard deviation of system operation cost by 22.35% and 27.41%, respectively; 2) ensures 100% photovoltaic accommodation; and 3) maintains low conservativeness and complexity simultaneously. Above all, this study provides an effective approach for comprehensive ultilization of clean energies under multiple uncertainties. [ABSTRACT FROM AUTHOR]

A new methyl chloride (CH3Cl) capture and dehydration process using two ionic liquids (ILs) was designed and systematically studied. ILs [EMIM][Ac] and [EMIM][BF4] were screened out as CH3Cl capture and drying absorbents through the COSMO‐RS model. The result of solubility experiment suggests [EMIM][Ac] has an excellent solvent capacity for CH3Cl at mild operation conditions. The bench‐scale CH3Cl absorption experiments further confirmed the outstanding CH3Cl capture ability of [EMIM][Ac]. Besides, the water content of outlet gas can be decreased to 452 ppm (mass fraction) using [EMIM][BF4] in the dehydration experiment. The industrial‐scale CH3Cl capture and dehydration process was simulated and optimized. Compared to the benchmarked triethylene glycol process, IL process has higher product purity (99.99 wt%), and lower energy consumption. The quantum chemical calculations clearly revealed the relationship between hydrogen bond and separation performance. This study provides a decision‐making basis for designing green process associated with volatile organic compounds. [ABSTRACT FROM AUTHOR]

Abstract Background Cervical dysplasia and tumorigenesis have been linked with numerous chromosomal aberrations. The goal of this study was to evaluate 35 genomic regions associated with cervical disease and to select those which were found to have the highest frequency of aberration for use as probes in fluorescent in-situ hybridization. Methods The frequency of gains and losses using fluorescence in-situ hybridization were assessed in these 35 regions on 30 paraffin-embedded cervical biopsy specimens. Based on this assessment, 6 candidate fluorescently labeled probes (8q24, Xp22, 20q13, 3p14, 3q26, CEP15) were selected for additional testing on a set of 106 cervical biopsy specimens diagnosed as Normal, CIN1, CIN2, CIN3, and SCC. The data were analyzed on the basis of signal mean, % change of signal mean between histological categories, and % positivity. Results The study revealed that the chromosomal regions with the highest frequency of copy number gains and highest combined sensitivity and specificity in high-grade cervical disease were 8q24 and 3q26. The cytological application of these two probes was then evaluated on 118 ThinPrep™ samples diagnosed as Normal, ASCUS, LSIL, HSIL and Cancer to determine utility as a tool for less invasive screening. Using gains of either 8q24 or 3q26 as a positivity criterion yielded specificity (Normal +LSIL+ASCUS) of 81.0% and sensitivity (HSIL+Cancer) of 92.3% based on a threshold of 4 positive cells. Conclusions The application of a FISH assay comprised of chromosomal probes 8q24 and 3q26 to cervical cytology specimens confirms the positive correlation between increasing dysplasia and copy gains and shows promise as a marker in cervical disease progression.

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The Biomass-Photovoltaic-Hydrogen Integrated Energy System (BPH-IES) is receiving increasing attentions due to the utilization of hydrogen storage for renewables accommodation. However, owing to its internal components and capability for participating in electricity and carbon markets, source-load-market uncertainties such as the random photovoltaic output, loads, as well as electricity and carbon prices are non-negligible, which seriously hinders the stable operation and realization of economic and environmental benefits for BPH-IES. In this paper, in view of the insufficient samples and the time-series attribute for the uncertainties, a novel Time-series Generative Adversarial Network (TimeGAN) based Distributionally Robust Optimization (DRO) model is proposed for BPH-IES scheduling. Based on TimeGAN learning the dynamics of the limited samples of uncertainties, sufficient generated samples are obtained with approximating the real distributions. Then, the temporal covariance conditions are introduced in the ambiguity set construction, aiming at getting rid of those distributions unmatching the temporal correlations of the enlarged samples. Finally, DRO model for scheduling is established, which jointly optimizes multi-energy operation and electricity-carbon trading strategy for BPH-IES considering the "worst-case" distributions within the narrowed ambiguity set. The solution procedure is developed according to the duality and semi-definite programming theories. Simulations have verified that for BPH-IES, the proposed model: 1) improves the economic and environmental benefits by 10.04% and 7.79% respectively, due to the TimeGAN and temporal covariance based modifications; 2) maintains operation stability and 100% renewables accommodation under the source-load uncertainties; 3) reduces the fluctuation of benefits via considering the market uncertainties. • BPH-IES scheduling under source-load-market uncertainties is studied. • TimeGAN based DRO model is proposed for BPH-IES scheduling. • Limited time-series samples of uncertainties are expanded based on TimeGAN. • DRO scheduling is carried out with the temporal covariances of the enlarged samples. • Benefits improvement and renewables accommodation are verified. [ABSTRACT FROM AUTHOR]

BACKGROUND. Testing for human papillomavirus (HPV) is used in the triage ofwomen with a cervical cytology of atypical squamous cells of undetermined significance (ASCUS). A fluorescent in situ hybridization assay was developed forthe detection of HPV using the catalyzed receptor deposition technique (HPV-CARD). In this study, the utility of this assay was tested for the detection of HPVin liquid-based cervical cytology specimens.METHODS. A total of 195 liquid-based cytology specimens were analyzed usingthe HPV-CARD assay. The results from the assay were compared with HPV polymerase chain reaction (PCR) and typing results. The number of HPV-infectedcells and the staining pattern was correlated with the cytology classification.RESULTS. A 91% concordance between HPV-CARD and PCR was observed for thedetection of high-risk HPV viruses. A 78% concordance was observed for specimens that were negative for HPV. In ASCUS, low-grade squamous intraepitheliallesion (LSIL), and high-grade squamous intraepithelial lesion (HSIL) categories,the average number of HPV-positive cells per slide was 19 cells, 127 cells, and450 cells, respectively. The number of cells with a punctate staining, suggestive ofHPV integration, was 21% in ASCUS, 34% in LSIL, and 46% in HSIL specimens.CONCLUSIONS. The results of the current study indicate positive correlationsbetween the severity of the disease and the increased overall quantity of HPV-positive epithelial cells in cervical cytology specimens and accumulation of cellswith punctate staining suggestive of integrated HPV. In summary, the developedHPV-CARD assay was found to provide novel information regarding the proportion and staining pattern of HPV-infected epithelial cells in different cytologiccategories of cervical specimens. [ABSTRACT FROM AUTHOR]

Waste-to-energy (WTE) is a technology that converts inexhaustible waste into electricity, thus significantly alleviating energy crisis. Integrating hydrogen storage into WTE provides an effective way to store and utilize surplus electricity from WTE on-site (by producing hydrogen). Additionally, integrating power-to-gas (P2G) into WTE provides an effective way to reduce CO 2 emission from WTE on-site (by producing natural gas). To this end, a novel waste-driven renewable energy system (WRES), which is consisted of WTE, hydrogen storage, and P2G, has been proposed. However, the uncertain waste supply and electrical load markedly interfere with WRES operation. Meanwhile, when WTE, hydrogen storage, and P2G belong to different agents, the collaborative benefit from WRES operation should be rationally allocated among agents for system sustainability. This paper endeavors to achieve WRES scheduling and collaborative benefit allocation for WTE, hydrogen storage, and P2G under uncertainties. Firstly, a temporal relevance based distributionally robust optimization model is proposed for WRES scheduling under uncertainties, in which the possible range of the joint distribution for uncertainties is depicted by data covariance matrices involved ambiguity set. Secondly, collaborative benefit is allocated according to WTE, hydrogen storage, and P2G contributions, in which Gauss-Legendre quadrature formula is integrated with Aumann-Shapley value method to reduce calculation complexity. Finally, simulation results show that 1) the proposed scheduling model guarantees the economic and stable operation of WRES under uncertainties. 2) after considering the temporal relevance, WRES operation benefit is 8.35 % higher, which indicates that the proposed scheduling model has superiority in decision conservatism by introducing temporal relevance to remove impractical distributions in ambiguity set. 3) the proposed allocation model rationally distributes the collaborative benefit according to contributions, and presents lower calculation complexity, e.g., the calculation time is 95.52 % lower than the Shapely value method. This paper provides policy insights to promote widespread application and sustainable operation of WRES. • Collaborative scheduling and benefit allocation are studied for WRES. • Temporal relevance based DRO model is proposed for collaborative scheduling. • Aumann-Shapley value method plus Gauss-Legendre quadrature for benefit allocating. • The proposed scheduling model can reduce conservatism and resist uncertainty. • The proposed allocation model can reduce calculation complexity and keep fairness. [ABSTRACT FROM AUTHOR]

Pumped storage is crucial for maintaining energy balance and smoothing out the fluctuations from renewable sources. Yet, it is limited by its fixed capacity and lack of expandability post-construction, posing challenges to its long-term adaptability in the context of increasing installed renewable sources capacity. Underwater hydrogen storage, however, characterized by its green, low-carbon profile and ability for rapid energy release and long-term storage, complements pumped storage by enhancing the system's overall energy storage capacity and flexibility. Therefore, this paper proposes an innovative way for the pumped storage power station capacity expansion based on the underwater hydrogen storage introduction. On the basis of technical support of underwater hydrogen storage and time-series attribute consideration of uncertainties, a multi-objective distributionally robust optimization model with temporal correlation is constructed for underwater hydrogen storage planning and further scheduling pumped storage power station and underwater hydrogen storage to operate. Firstly, the system structure and operation mode after introducing underwater hydrogen storage into pumped storage power station are designed. Secondly, the temporal covariance conditions are introduced in a moment-based ambiguity set, with the aim of removing those distributions that do not match the temporal correlation of the historical forecasting errors samples. Finally, considering the "worst-case" distribution within the narrowed ambiguity set, an improved multi-objective distributionally robust optimization is constructed, which optimizes the capacity of each equipment in underwater hydrogen storage and the operation strategy of pumped storage power station and underwater hydrogen storage. Simulation mainly verifies: 1) it increases the economic revenue, electric load supply and photovoltaic output accommodation by 3.35 × 108 $, 2033.091 MW and 67584.054 MW, respectively, due to the introduction of underwater hydrogen storage for pumped storage power station expansion. 2) it improves cost savings, load supply reliability and photovoltaic output accommodation by 0.224 %,3.231 % and 2.722 % respectively, due to the introduction of temporal covariance to modify distributionally robust optimization model. • Underwater hydrogen storage introducing for pumped storage power station expansion. • Improved distributionally robust optimization is employed for planning and operating. • Temporal covariance conditions are introduced to modify moment-based ambiguity set. • Economy and reliability are improved due to underwater hydrogen storage introduction. • The proposed model can resist multiple uncertainties and reduce conservatism. [ABSTRACT FROM AUTHOR]