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In nuclear power plants, the loss-of-coolant accident (LOCA) stands out as the most prevalent and consequential incident. Accurate breach size diagnosis is crucial for the mitigation of LOCAs, and identifying the cause of an accident can prevent catastrophic consequences. Traditional methods mostly focus on combining model algorithms and utilize intricate composite model neural network architectures. However, it is crucial to investigate whether greater complexity necessarily leads to better performance. In addition, the consideration of the impact of dataset construction and data preprocessing on model performance is also needed for model building. This paper proposes a framework named DeepLOCA-Lattice to experiment with different preprocessing approaches to fundamental deep learning models for a comprehensive analysis of the diagnosis of LOCA breach size. The DeepLOCA-Lattice involves data preprocessing via the lattice algorithm and equal-interval partitioning and deep-learning-based models, including the multi-layer perceptron (MLP), recurrent neural networks (RNNs), convolutional neural networks (CNNs), and the transformer model in LOCA breach size diagnosis. After conducting rigorous ablation experiments, we have discovered that even rudimentary foundational models can achieve accuracy rates that exceed 90%. This is a significant improvement when compared to the previous models, which yield an accuracy rate of lower than 50%. The results interestingly demonstrate the superior performance and efficacy of the fundamental deep learning model, with an effective dataset construction approach. It elucidates the presence of a complex interplay among diagnostic scales, sliding window size, and sliding stride. Furthermore, our investigation reveals that the model attains its highest accuracy within the discussed range when utilizing a smaller sliding stride size and a longer sliding window length. This study could furnish valuable insights for constructing models for LOCA breach size estimation. [ABSTRACT FROM AUTHOR]

The failure of wellbore sealing will cause leakage of greenhouse gases, such as carbon dioxide and methane, which will harm oil and gas recovery and environmental safety. Cementing is an important part of wellbore sealing. Only good cementing can keep the wellbore seal for a long time and improve the well life. In this study, we considered the construction of a horizontal shale oil well in eastern China as the background and analysed the rheological properties of the annulus fluid. We developed a displacement motion model and a calculation model for the annulus dynamic equivalent circulation density, and numerical simulations were used to study the impact of the dosage and injection sequence of the pad fluid on the displacement efficiency and annulus dynamic equivalent circulation density. The results show that when the pad fluid is composed completely of flushing fluid, the displacement performance is better than that of the spacer. By increasing the dosage of the flushing fluid from 0.3 times the annular volume to 1.0 times, the displacement efficiency can be increased by 3.3%, and the retention of the drilling fluid is also reduced by 3.6%. However, it can lead to a significant reduction in the annulus dynamic equivalent circulation density and increase in the risk of leakage. After adding the spacer, the structure of the flushing fluid–spacer provides the optimal injection sequence. Considering the application status in the field example well, it was shown that it can not only ensure the safety of cementing operations, but also improve the displacement efficiency. The results of this study have important theoretical significance and application value and can provide guidance for the optimisation design of the engineering scheme. [ABSTRACT FROM AUTHOR]

Fault diagnosis plays an important role in complex and safety-critical systems such as nuclear power plants (NPPs). With the development of artificial intelligence (AI), extensive research has been carried out for fast and efficient fault diagnosis based on intelligent methods. This paper presents a review of various AI-based system-level fault diagnosis methods for NPPs. We first discuss the development history of AI. Based on this exposition, AI-based fault diagnosis techniques are classified into knowledge-driven and data-driven approaches. For knowledge-driven methods, we discuss both the early if–then-based fault diagnosis techniques and the current new theory-based ones. The principles, application, and comparative analysis of the representative methods are systematically described. For data-driven strategies, we discuss single-algorithm-based techniques such as ANN, SVM, PCA, DT, and clustering, as well as hybrid techniques that combine algorithms together. The advantages and disadvantages of both knowledge-driven and data-driven methods are compared, illustrating the tendency to combine the two approaches. Finally, we provide some possible future research directions and suggestions. [ABSTRACT FROM AUTHOR]

Herein, DES lignin was obtained by pretreatment of grapevine with a deep eutectic solvent (ChCl-LA). A novel chitosan-DES lignin composite aerogel material (CS-LIG aerogel) was prepared to adsorb methylene blue (MB), Congo red (CR), catechin (C), and epicatechin (EC). The CS-LIG aerogel was systematically characterized by modern technological instruments. It was demonstrated that the DES lignin was successfully incorporated and had an important effect on the morphological structure and adsorption of dyes and natural products in the aerogel. The adsorption kinetic models for both adsorbed CR and MB are pseudo-second-order models. Adsorption isotherms followed Langmuir for the adsorption of CR and Freundlich for the adsorption of MB. The π-π interaction and hydrogen bonding of DES lignin aromatic groups in CS-LIG aerogels were responsible for the adsorption of C and EC with 86.42 % and 90.85 % removal rates, respectively. This study opens a new avenue for the high-value utilization of DES lignin and the preparation of chitosan-based composites for the adsorption of dyes and purification of natural products. • DES lignin incorporation enhances the thermal stability of CS aerogel. • Adsorption of dyes on CS-LIG aerogels is mainly electrostatic and hydrogen bonding. • The CS-LIG aerogel can selectively adsorb C and EC from proanthocyanidins. • Lignin π-π interactions of aromatic groups are primarily reason for adsorb C and EC. [ABSTRACT FROM AUTHOR]

Manganese oxides supported on γ-AlO, amorphous SiO, MCM-41, and TiO prepared by an impregnation method were used as heterogeneous catalysts for epoxidation of alkenes with 30 % HO in the presence of NaHCO aqueous solution. The effect of support and manganese loading on their activity was studied. The 1.3-MnO/γ-AlO exhibited superior epoxidazing activity of styrene, compared with other supported MnO. Hydrogen temperature-programmed reduction, UV-vis and ESR analyses suggested that Mn (catalytic activity species) dominated in 1.3 % MnO/γ-AlO due to a strong interaction between MnO and γ-AlO. Recycling studies showed the catalyst was a heterogeneous one and retained its activity after recycling four times. [ABSTRACT FROM AUTHOR]

Highlights: [•] Mn-MCM-41 has been prepared by different synthetic routes. [•] The structure of the catalysts confirmed by different physico-chemical techniques. [•] Mn-M41-K of catalysts exhibited high activity for selective epoxidation of styrene. [•] The MnO x dispersed in channels of Mn-M41-K did almost not leach and could be recyclable. [•] One possible reaction mechanism is proposed. [Copyright &y& Elsevier]

Abstract: In present work, the [PdCl4]2− ions were successfully supported on as-synthesized [CTA+]MCM-41 materials through adsorption method. Subsequently, the composite materials were reduced by sodium borohydride, followed by being extracted of [CTA+] surfactants with acidified ethanol. The resulted solid (denoted as Pd-M41-AE) could be used as an efficient catalyst for the solvent-free aerobic oxidation of benzylic alcohol under atmospheric pressure. The structures of the samples were characterized by X-ray diffraction (XRD), N2 adsorption–desorption, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and thermogravimetry (TG) techniques. 0.4%Pd-M41-AE exhibited high activity (turnover frequency of 4344h−1) for the oxidation of benzyl alcohol, remarkably superior than other kinds of Pd-M41 at 100°C. Moreover, the superior turnover frequencies (69,162h−1 for benzyl alcohol, 69,920h−1 for 1-phenylethanol and 117,130h−1 for cinnamyl alcohol, respectively) were achieved over 0.05%Pd-M41-AE at 160°C. Recycling studies proved the recyclability of Pd-M41-AE as a heterogeneous catalyst, which did not lose the catalytic activity after four recycles appreciably. [Copyright &y& Elsevier]

Abstract: A series of manganese oxides (MnO, Mn3O4, Mn2O3 and MnO2) were prepared and firstly applied as heterogeneous catalysts for the liquid phase epoxidation of alkenes with 30% H2O2 in bicarbonate solution. Under our experimental conditions, MnO exhibited superior activity for the conversion of styrene to achieve ca. 100% with 92.4% selectivity of epoxide, compared to the other three manganese oxides as well as other metal oxides. Furthermore, recycling studies showed the good recyclability of MnO as a heterogeneous catalyst, which did not lose the catalytic activity after four reuses appreciably. [Copyright &y& Elsevier]

Deep eutectic solvents (DESs) have been extensively applied to pretreat lignocellulose; however, comparative research on acidic and alkaline DES pretreatment is relatively lacking. Herein, pretreatment of grapevine agricultural by-products with seven DESs were compared in terms of removal of lignin and hemicellulose and component analysis of the pretreated residues. Among the tested DESs, both acidic choline chloride-lactic (CHCl-LA), and alkaline potassium carbonate-ethylene glycol (K 2 CO 3 -EG) were effective in delignification. Thereafter, the CHCl-LA and K 2 CO 3 -EG extracted lignin was compared by analyzing their physicochemical structure changes and antioxidant properties. The results showed that the thermal stability, molecular weight, and phenol hydroxyl percentage of CHCl-LA lignin were inferior to K 2 CO 3 -EG lignin. It was found that the high antioxidant activity of K 2 CO 3 -EG lignin was mainly attributed to the abundant phenol hydroxyl, guaiacyl (G), and para-hydroxy-phenyl (H). By comparing acidic and alkaline DES pretreatments and their lignin nuances in biorefining, novel insights are derived for the scheduling and selection of DES for lignocellulosic pretreatment. • CHCl-LA pretreatment has a great advantage in removing lignin and hemicellulose. • K 2 CO 3 -EG pretreatment benefits lignin structure and thermal stability preservation. • Significant chemical shift in the guaiacyl lignin unit of K 2 CO 3 -EG lignin. • K 2 CO 3 -EG lignin retains more phenol hydroxyl have better antioxidant properties. [ABSTRACT FROM AUTHOR]

Analyzing heat fluxes of plants and soil is necessary to explore the thermal performance of green roofs. This paper presents mathematical expressions of heat fluxes of green roofs, and specially a heat and mass transfer model is built to get the distribution of temperature and moisture content in soil. The developed model is validated with experimental data from the intensive planted roof located in Chongqing. And the effectiveness of the model for predicting the temperature and water content variations are demonstrated by the comparison between the experimental results and simulation. Furthermore, the performance of green roof during summer in Chongqing is discussed based on the experiment. Through analyzing heat fluxes of green roofs, the study presents the contribution of each thermal behavior including reflection, convection, evapotranspiration and thermal storage to the thermal effects of the green roof quantitatively. The weight of various thermal behaviors of the green roof changes in different time, resulting in different thermal performance of green roofs. The study of the transient heat fluxes of green roofs will not only contribute to a high efficient usage but also a better application of engineering. [ABSTRACT FROM AUTHOR]

During the cementing process, the oil-well cement (OWC) inevitably comes into contact with oil-based mud (OBM), which contaminates the OWC due to the incompatibility between OBM and the OWC. As a solution, hydrophilic surfactants can reduce interfacial tension and enhance the wetting compatibility of oil and water. Therefore, adding surfactants to the OWC is expected to alleviate contamination caused by OBM. In this study, a new strategy was proposed to combine non-ionic surfactants and anionic surfactants to form a composite surfactant (OP-S2), which overcomes the defect that excessive use of anionic surfactants deteriorates the performance of the OWC—showing great potential in adjusting the compatibility between OBM and the OWC and reducing cement contamination. The mechanism of contamination alleviation during the cementing process was elucidated by comparing the anticontamination properties of a single non-ionic surfactant (OP-S1) and OP-S2. In addition, molecular dynamics (MD) and dissipative particle dynamics (DPD) simulations were used to verify the mechanism of different types of surfactants in removing contamination further, providing theoretical guidance for future research on anti-contamination agents. [Display omitted] • Combining non-ionic and anionic surfactants to form a composite surfactant (OP-S2). • OP-S2 solves the defect that excessive single surfactant worsens OWC performance. • OP-S2 can meet the safety and quality requirements of ancient Wells. • Through MD and DPD simulation, the mechanism of surfactant removal was explored. [ABSTRACT FROM AUTHOR]

Background: The preferred salvage treatment for children with relapsed/refractory acute myeloid leukemia (R/R‐AML) remains unclear. The combination of cladribine/Ara‐C/granulocyte‐colony stimulating factor and mitoxantrone (CLAG‐M) shown promising results in adult R/R‐AML. We aim to investigate the efficacy and safety of CLAG‐M versus mitoxantrone/etoposide/cytarabine (MEC) or idarubicin/etoposide/cytarabine (IEC) in R/R‐AML children. Methods: Fifty‐five R/R‐AML children were analyzed. The overall response rate (ORR), overall survival (OS), and progression‐free survival (PFS) at 3‐year were documented. Karyotype or mutations status were summarized as different risk groups. Results: The ORR was achieved in 80% (16/20) and 51% (18/35) of patients after one‐cycle of CLAG‐M and MEC/IEC treatment (p < 0.001). The CLAG‐M group's OS (66.8% ± 16.2% vs. 40.4% ± 10.9%, p = 0.019) and PFS (52.6% ± 13.7% vs. 34.9% ± 9.1%, p = 0.036) at 3‐year was significantly higher than the MEC/IEC group. In high‐risk patients, 33.3% experienced progression of disease (PD) and 22.2% dead in CLAG‐M group, while 50% experienced PD and 43.8% dead in MEC/IEC. When it comes to low‐risk group, none of them in CLAG‐M experienced PD or death, while up to 50% of patients received MEC/IEC suffered PD, and all of them died eventually. Similar results were also found in the intermediate‐risk group. Surprisingly, the presence of FLT3‐ITD was associated with poor outcome in both groups. The most common adverse events were hematologic toxicities, and the incidence was similar in both group. Conclusions: CLAG‐M group demonstrated effective palliation along with acceptable toxicity in R/R‐AML patients. However, patients with FLT3‐ITD may benefit less from CLAG‐M, owing to higher PD rate and all‐cause mortality than other patients. [ABSTRACT FROM AUTHOR]

Background: The prognosis of children with acute monocytic leukemia (AML‐M5) remains unsatisfactory and the risk profile is still controversial. We aim to investigate the prognostic value of clinical and cytogenetic features and propose a new risk stratification in AML‐M5 children. Methods: We included 132 children with AML‐M5. Overall survival (OS) and progression‐free survival (PFS) were documented. Cox regression was performed to evaluate the potential risk factors of prognosis. Results: The 5‐year‐OS was 46.0% (95% confidence intervals, 41.6%‐50.4%) in all patients. There was significantly lower OS in the age ≤ 3 years old (P =.009) and hyperleukocytosis (P <.001). The FMS‐like tyrosine kinase 3 (FLT3)‐internal tandem duplication (ITD) and MLL‐rearrangement carriers were associated with fewer survivors in all patients (37.1% and 36.7%) and chemotherapy‐only group (19.0% and 35.0%). Notably, the number of survivor with MLL‐rearrangement did not increase in hematopoietic stem cell transplant (HSCT) group. According to the Cox regression analysis, HSCT was a significantly favorable factor (P =.001), while hyperleukocytosis, age ≤ 3 years old, and BM blast ≥ 70% adversely affected the OS in all patients (all P <.05). Additionally, FLT3‐ITD was a risk factor for OS in the chemotherapy‐only group (P =.023), while hyperleukocytosis and age ≤ 3 years independently contributed to poor PFS (both P <.05). In comparison to the standard‐risk group, significant poorer outcome was found in the high‐risk group (both P <.005). Conclusions: We propose that AML‐M5 children with any of MLL‐rearrangement, FLT3‐ITD, hyperleukocytosis, BM blast ≥ 70%, or age ≤ 3 years old are classified into the high‐risk group, and HSCT is beneficial especially in patients with FLT3‐ITD mutation, hyperleukocytosis, and age ≤ 3 years old. Importantly, the choice of HSCT should be made more carefully in children with MLL‐rearrangement for its suboptimal performance. [ABSTRACT FROM AUTHOR]

Encapsulation has been extensively applied in the self-healing of cementitious materials due to the diversity of encapsulating materials. Nonetheless, the weak interfacial bonding of polymer capsules and cementitious materials commonly reduces the healing efficiency, the preparation of which is complicated and not environmentally friendly. In this paper, a nano-silica reinforced calcium alginate/epoxy resin capsule (S1) was prepared using a simple and green chelating method at room temperature. The strong bonding of the shell containing nano-silica with cementitious materials makes it easier for capsules to be triggered to achieve higher self-healing efficiency. Their effects on cementitious materials were measured to determine the reinforcing mechanisms, microstructure and mechanical properties of capsules. The experimental results demonstrated that S1 possessed higher thermal stability (310.0 °C), higher mechanical strength and lower water absorption (46.95% in cement filtrate) than samples without nano-silica (S0). The compressive strength of S1 cementitious material increased by 18.9% compared with S0 cementitious material because of the decrease in porosity and the increased mechanical properties of the S1 capsule. Moreover, the self-healing efficiency of S1 cementitious material improved greatly by 112.7%, which was related to the more efficient rupture of S1. The nano-silica in the capsule increased the surface roughness of S1 and reacted with cement matrix via a pozzolanic reaction, thereby achieving efficient self-healing of cementitious system through a stronger interface. [Display omitted] • A nano-silica reinforced calcium alginate/epoxy resin capsule was prepared through green chelation at room temperature. • The improvement in thermal stability mechanical strength of capsules by adding nano-silica were analyzed. • The influence of capsules on the compressive strength and self-healing efficiency of cementitious system was investigated. • The effect of nano-silica on the interface between cement matrix and capsules was explored. [ABSTRACT FROM AUTHOR]

ObjectiveThe present study aimed to compare the effects of a general dietary intervention and an intervention with low glycaemic load (GL) on glycaemic control, blood lipid metabolism and pregnancy outcomes in women with gestational diabetes mellitus.DesignParticipants were randomly assigned to two groups, receiving either an individualized general dietary intervention (Control group) or an intensive low-GL intervention (Low-GL group) every two weeks, from 24–26 weeks of gestation to delivery.SettingThe Center of Maternal Primary Care in Guangdong General Hospital, China.SubjectsNinety-five women with gestational diabetes mellitus were enrolled from June 2008 to July 2009.ResultsAfter the intervention, both groups significantly decreased their dietary intakes of energy, fat and carbohydrate. The Low-GL group had significantly lower values for GL (122 v. 136) and glycaemic index (50 v. 54) but greater dietary fibre intake (33 v. 29 g/d) than did the Control group (all P<0·01). Significantly greater decreases in fasting plasma glucose (−0·33 v. −0·02 mmol/l, P<0·01) and 2 h postprandial glucose (−2·98 v. −2·51 mmol/l, P<0·01), significantly lower increases in total cholesterol (0·12 v. 0·23 mmol/l) and TAG (0·41 v. 0·56 mmol/l) and a significantly lower decrease in HDL cholesterol (−0·01 v. −0·11 mmol/l) were also observed in the Low-GL group compared with the Control group (all P<0·05). There were no significant differences in body weight gain, birth weight or other maternal–fetal perinatal outcomes between the two groups.ConclusionsThe low-GL targeted dietary intervention outperformed the general dietary intervention in glycaemic control and the improvement of blood lipid levels in women with gestational diabetes mellitus. [ABSTRACT FROM AUTHOR]

Abstract: Fe-containing HMCM-68 was prepared by a direct hydrothermal method (Fe-HMCM-68) or by impregnation of HMCM-68 with different iron precursors (Fe2O3/HMCM-68, FeCl3/HMCM-68). Their structure and acid properties were characterized by XRD, N2 adsorption, UV–Vis and NH3-TPD. The benzylation of toluene by benzyl chloride showed that these Fe-containing HMCM-68 zeolites were highly active catalysts for this reaction and could be reused. The activity of the Fe-containing HMCM-68 is controlled mainly by their redox properties and the effect of zeolitic acidity has been further discussed. [Copyright &y& Elsevier]

Abstract: In this work, it was found that alkali-treated zeolites could efficiently catalyze oxidation of toluene with H2O2 in aqueous media. No heavy metals or their oxides were employed in the synthesis of catalyst and no additives were used in this catalytic system. Through optimizing the experimental conditions, alkali-treated HZSM-5 exhibited good catalytic activity for toluene oxidation in only 5h at a low temperature (below 100°C): 32.0% conversion of toluene with selective formation of 25.0% benzaldehyde, 20.8% benzyl alcohol and 27.5% benzoic acid. Moreover, the results of reusability studies indicated that alkali-treated HZSM-5 was a durable and green catalyst for toluene oxidation in aqueous media. The changes in acidities and textural features of the zeolites induced by alkali-treatment were characterized by ammonia temperature programmed desorption (NH3-TPD) and X-ray powder diffraction (XRD), respectively. The results indicated the reactivity for toluene oxidation could be related to the amount of species ph name="rad" /> and his system. A probable redox mechanism for toluene oxidation catalyzed by alkali-treated zeolites in aqueous media was proposed in this work. [Copyright &y& Elsevier]

Abstract: Mesoporous materials, especially functionalized ones, have become a promising carrier for enzyme immobilization. We synthesized room temperature ionic liquid-decorated mesoporous SBA-15 (RTIL-SBA-15) for papain immobilization. The results of powder XRD, IR and N2 adsorption–desorption isotherms have confirmed that ionic liquid [Simim+][Cl−] was successfully grafted on the surface of SBA-15. As a consequence of the electrostatic attraction between the cation [Simim+] and the negatively charged papain, RTIL-SBA-15 had an advantage over SBA-15 when papain was immobilized at pH=9.00. The kinetic study showed that the interaction between papain and the carrier was stronger after ionic liquid modification. In the casein hydrolysis, the papain immobilized on RTIL-SBA-15 showed a higher specific activity than that on SBA-15, implying that the ionic liquid [Simim+][Cl−] was beneficial to improve the activity of the immobilized papain. The optimum pH of the immobilized papain was shifted to higher than that of free enzyme. [Copyright &y& Elsevier]