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The solubility of 1,1-diamino-2,2-dinitroethylene (FOX-7) was measured by using a laser monitoring system in binary (N-methyl pyrrolidone + acetone, ethanol, water) mixed solvents with temperatures changing from 293.15 K to 333.15 K under 0.1 MPa. The experimental solubility data for FOX-7 were correlated and fitted to thermodynamic models such as van't Hoff model, modified Apelblat model, and Yaws model. The results show that the solubility of FOX-7 increases with increasing temperature and N-methyl pyrrolidone ratio. Three models can be used to correlate the solubility data commendably. However, the Yaws model fits best for the solvent system selected in this work. At last, the standard dissolution enthalpy, standard dissolution entropy, and standard Gibbs free energy of FOX-7 can be calculated. It was found that the dissolution of FOX-7 in all test solvents was endothermic and non-spontaneous. [ABSTRACT FROM AUTHOR]

A skeleton structure AlON (aluminum oxynitride) carrier with light transmission performance was prepared by carbothermal reduction and nitridation (CRN). The AlON carrier can disperse nano active components and enhance its photocatalytic performance. The microstructure of the TiO 2 /AlON composite photocatalyst shows that the dispersion of the agglomerated TiO 2 is achieved by the physical adsorption mechanism, the embedding mechanism and the single particle dispersion mechanism. The morphology of the BiVO 4 /AlON and g-C 3 N 4 /AlON composite photocatalysts further proves the universality of the AlON carrier in the dispersion of nano photocatalyst. The photocatalytic performance of the nano active component was enhanced by combining with AlON carrier. After 240 min of visible light irradiation, the degradation rate of MB increased by 7.4% (BiVO 4 /AlON) and 8.1% (g-C 3 N 4 /AlON), respectively. High light transmittance was the main reason for AlON carrier to improve the photocatalytic performance of loaded active components. In addition, AlON carrier type composite photocatalyst can be reused for many times because it has physicochemical stability and can be recovered easily. [ABSTRACT FROM AUTHOR]

Identifying interactions among river water, groundwater and salt lake brine is important for sustainable exploitation of brine mineral resources. In this study, we investigated the water exchange rate in dry and wet seasons, and assessed the influence of seasonal water exchange on brine concentration and crystallization process in the Nalenggele (NLGL) catchment of Qaidam Basin, China. The results show that the surface water infiltration and groundwater recharge rates in the wet season were 2.81 × 10−3 and 1.15 × 10−3 m3/(s·m) in upstream, 1.63 × 10−2 and 1.53 × 10−2 m3/(s·m) in midstream, and 2.83 × 10−4 and 6.82 × 10−5 m3/(s·m) in downstream, respectively; while their counterparts in the dry season were 9.81 × 10−4 and 5.05 × 10−4 m3/(s·m) in upstream, and 8.34 × 10−3 and 7.78 × 10−3 m3/(s·m) in midstream, respectively. The water exchange strongly influenced brine concentration and crystallinzation process, with brine chemistry belonging to 3K2SO4·Na2SO4 and KCl types in wet and dry seasons, respectively. The strong water exchange in wet season destroyed the water-salt balance, while the low water exchange rate in dry season facilitated preparation of KCl products. [ABSTRACT FROM AUTHOR]

Objectives: To investigate feasibility and safety of autologous blood in preoperative computed tomography (CT)-guided localization of pulmonary ground-glass nodules (GGNs) by comparing to mico-coil prior to video-assisted thoracoscopic surgery.Methods: Clinical data of patients with GGNs who underwent video-assisted thoracoscopic surgery followed by preoperative CT-guided autologous blood or micro-coil localization was retrospectively reviewed in our department between September 2019 and November 2021. The localization duration, localization success rate, localization-related complication, localization cost, operation time, and conversion rate were compared between the 2 localization groups.Results: Totally 65 patients with 65 GGNs were included in our study, with 34 patients in autologous blood group (group B) and 31 patients in micro-coil group (group M). There is no conversion to thoracotomy. The age, sex, nodule location, diameter of nodule and distance from the pleura between the 2 groups were statistically comparable. Compared with group M, group B had similar localization success rate (94.1% vs 83.9%, P = 0.183) but shorter localization time (14.50 ± 2.61 min vs 16.35 ± 2.30 min, P = 0.004), lower cost ($92.4 ± 3.2 vs $475.6 ± 8.5, P = 0.001), and lower incidence of puncture complications (3.0% vs 19.3%, P = 0.042).Conclusions: The autologous blood localization is an effective and more economical method for preoperative GGNs localization, and is associated with fewer complications compared to micro-coil localization. [ABSTRACT FROM AUTHOR]

Increasing the surface area of active materials is a crucial approach to enhance the capacity of supercapacitors. In this study, we present an interdigitated supercapacitor featuring a double-layer active material prepared using a sacrificial layer method. The replacement of the insulating substrate with a gel electrolyte facilitates ion motion between the active electrodes. Finite element analysis (FEA) and electrochemical experiments confirm that the utilization of double-layer active material can significantly improve the capacity (1.5–1.85 times higher than traditional structures). The electrochemical performance of the three active materials has been significantly improved after using the double-layer active material structure, which proves that the method in this paper has strong material compatibility. Furthermore, an interdigital supercapacitor (ISC) is fabricated using electrodes with double-layer active material through the sacrificial layer method and its electrochemical performance is evaluated. At a scan rate of 10 mV·s-1, ISC exhibits an impressive area-specific capacitance as high as 68.4 mF·cm-2. Remarkably, ISC can maintain stable power output even under extreme deformation and fatigue testing conditions. This strategy involving interdigitated supercapacitors with double-layer active materials prepared via the sacrificial layer method presents a promising solution for flexible energy storage devices. • Use sacrificial layer method to remove the substrate. • A double-layer active material structure with increased capacity is proposed. • Replace the insulating substrate with a gel electrolyte. [ABSTRACT FROM AUTHOR]

The α-Al 2 O 3 /C mixtures were prepared by ball milling, and then AlON powders were synthesized by carbothermal reduction and nitridation (CRN). The effects of α-Al 2 O 3 particle size, carbon powders morphology and particle size on the morphology and particle size of the synthesized AlON powders were studied. The results showed that as the particle size of α-Al 2 O 3 increases, the particle size of the synthesized AlON powders will also increase, but the surface morphology will not be affected. The increase of the carbon particle size will increase the particle size of the synthesized AlON powders. The pore size and number of pores of the synthetic AlON powders were very similar to the morphological characteristics of the carbon powders. In addition, the mechanism of controlling the synthesis of AlON powder with α-Al 2 O 3 and carbon as raw materials was also discussed. [ABSTRACT FROM AUTHOR]

The Gas Hure Salt Lake (GHSL) in the northwestern Qaidam Basin, western China, is rich in boron (B) resources, but its B‐resource origin is hardly known. Hydrochemical compositions and B isotope characteristics of different waters were collected around the GHSL, including the river water, stream water, spring water, salt‐lake brine, intercrystalline brine, well water, drilling brine, and solar pond brine. The hydrochemical signatures suggest that silicates, carbonates and evaporates are the main B‐bearing rocks during the water dynamic. The reservoir estimation of B resources shows that the Kulamulekesay River (KLMR) and the Atekan River (ATKR) contribute annually 18.3 tons and 22.84 tons of B, respectively, with a total amount of 11.72 × 104 tons of B during the past 5.7 ka. In comparison with the known B reservoir (32.96 × 104 tons) in the GHSL, a significant amount of B in the GHSL was probably recharged from deep fluids and sediments around the GHSL. The B concentration and B‐enrichment degree are shaped by the evaporation process, which are highly elevated at the carnallite and bischofite stages. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common cancer in women, and triple-negative breast cancer (TNBC) accounts for about 15–20% of all breast cancer. High mobility group AT-hook 2 (HMGA2) is overexpressed in some tumors and closely associated with patients' prognosis. However, the mechanisms involved in the regulation of HMGA2 in TNBC still remain unclear. In this study, HMGA2 level in TNBC cell lines was analyzed by western blot. After knockdown of HMGA2 expression by RNA interference in TNBC cell lines MDA-MB-231 and SUM149, wound healing and transwell assays were conducted to examine the effects of HMGA2 on migration and invasion. Tumor metastasis was assessed in amouse xenograft model invivo. Furthermore, expression levels of epithelial–mesenchymal transition (EMT) biomarkers and involvement of the Hippo-YAP pathway were detected by western blot. Compared to normal breast epithelial cells, the expression levels of HMGA2 were significantly increased in TNBC cell lines (all P<.05). Downregulation of HMGA2 dramatically inhibited the migration and invasion of MDA-MB-231 and SUM149 cells (all P<.01) invitro, and suppressed the tumor metastasis of nude mice xenograft model invivo. Western blot analysis revealed alterations in EMT biomarkers: the expression of mesenchymal markers N-cadherin, Vimentin and Snail were decreased, while the expression of epithelial marker E-cadherin was increased. Downregulated expression of HMGA2 attenuated Hippo-YAP related protein expression and the stability of YAP. HMGA2 is highly expressed in TNBC cells. Downregulation of HMGA2 inhibits the migration and invasion of TNBC and invivo tumor metastasis mediated through inhibition of EMT and Hippo-YAP pathway. [ABSTRACT FROM AUTHOR]

In this article, the iterative learning control (ILC) problem is investigated for a class of stochastic time-varying systems with variable pass lengths. The randomness of the pass lengths is described by the recursive interval Gaussian distribution, and a modified iteration-average operator is developed to construct the novel ILC scheme for overcoming the limitation of conventional ILC algorithms that every pass must end in a fixed time of duration throughout the repetition. The proposed ILC approach works effectively to guarantee the boundedness of the tracking errors, which is demonstrated by a practical case study on a type of robot manipulator with two joints. [ABSTRACT FROM AUTHOR]

• Darker continuous phase in gas-liquid two-phase image is distinguished efficiently • The Betti numbers is well curve-fitted by a four-parameter logistics model. • The topological evolution of discrete and continuous phases are synergistic. • An index for characterizing synergy is correlated with heat transfer coefficient. • New metric of flow regime control based on two-phase flow evolution is obtained. The marker-controlled multiple watershed segmentation are achieved to distinguish darker continuous phase in gas-liquid two-phase flow patterns efficiently. Each plot of the Betti numbers β i is curve-fitted using a four-parameter logistics model, for characterizing mixing effects. Similarity between adjacent pixels can be quantified by the distance. The β 1 of continuous phase decreases linearly at distance ≥ 2, which can be used to determine the threshold for segmentation. Repeated tests with different pixels and methods are conducted to ensure the repeatability and effectiveness of this model. More interestingly, we find that the rapid increase of β 1 of bubbles swarm coincides with the evolution of β 1 of continuous phase, and the median of difference of β 1 between the two phases in the visible window, as a novel metric of flow regime control is obtained and correlated with average volumetric heat transfer coefficient. This dynamic image analysis method, equipped with computational homology, provides the ability of evaluation of the spatial flow structure from a two-dimensional image and can be used to control the process. [ABSTRACT FROM AUTHOR]

• A reciprocating and rotating coupled agitator is proposed. • A new algorithm for judging mixing time is proposed. • Effectiveness of the novel method is verified on both CFD and experimental. • The power consumption and chaos characteristics of the agitator were studied. • This agitator can be used in engineering fields. In this study, a reciprocating and rotating coupled agitator was proposed to enhance the quality of the liquid–liquid mixing state in a laminar flow, and validated using experimental and numerical approaches. The effects of impeller amplitude (A i), impeller reciprocating speed (v i), and impeller hovering time (t i) at a constant rotating speed on the mixing effect were studied. The results showed that the mixing effect of this agitator was much superior to that of a traditional rotating agitator under proper parameters. Under the impeller reciprocating motion, a large-scale vortex is generated under the impeller, which can significantly enhance the mixing effect. The mixing efficiency under the best mixing condition (A i = 0.05 m, v i = 0.005 m/s, t i = 15 s) in the experiment is 4.71 times than that of the traditional agitator. [ABSTRACT FROM AUTHOR]

[Display omitted] • A serpentine structure with low curvature is designed to improve stability. • By sacrificing the substrate, the stretchability of the SSC electrode is improved. • The patterned electrolyte thin film was prepared. • The supercapacitor with high tensile strength and high stability was prepared. Optimizing electrode structures is a promising solution for wearable electronics and flexible power sources. Nevertheless, there are still significant challenges in how to get rid of the constraints of the substrate and electrolyte on the electrode structure, thereby reducing the impact of such constraints on the elongation of supercapacitors and stabilizing the electrochemical output. In this work, a serpentine structure of low curvature (SSLC) was designed and fabricated by comparing the effect of the curvature of the turning structure on the performance of the serpentine structure. The superiority of SSLC electrodes over existing electrode structures is verified using finite element analysis (FEA) and stability experiments. Further, the SSLC electrode is used for physiological signal detection (ECG, EMG, GSR), showing excellent stability and low electrode–skin contact impedance, which is better than the medical wet electrode. A high-stretch supercapacitor (SSC) was prepared by sacrificing the substrate of the SSLC electrode and integrating the patterned electrolyte film. When the scan rate is 10 mV·s−1, the area specific capacitance of SSC is as high as 197.9 mF·cm−2. Under extreme deformation conditions (stretch 100%, bend 180°, twist 180°) SSC can maintain stable output. And after 10,000 charge–discharge cycles, the SSC can still output 91.96% of the initial power stably, indicating that the prepared SSC has high stretchability and stability. With highly stretchable and stable low-curvature serpentine structure electrodes, the SSC coupled with patterned electrolyte films and sacrificial substrate electrodes in this paper offer a promising solution for stretchable flexible power supplies and wearable electronics. [ABSTRACT FROM AUTHOR]

Abstract AlON has been reported to have photocatalytic capability under ultraviolet-light (UV-light), which can be improved by fabricating large-sized powder (~20 µm) having porous skeleton microstructure. To further enhance photocatalytic property of AlON, highly photocatalytic-efficient nanocrystalline TiO 2 was loaded onto both the outer and inner surface of porous AlON particles by hydrothermal method. In order to ensure easy recovery without secondary pollution, the obtained composite powder was filtered in deionized water three times to remove both small-sized AlON and free TiO 2 particles to produce a composite photocatalyst with particle size >10 µm. The proposed TiO 2 /AlON showed excellent photocatalytic performance on Methylene blue (MB) and Methyl orange (MO) for 97.9% and 99.1% of pollutants (in 30 mg/L, 40 mL solution) being degraded by 50 mg as-synthesized composite photocatalyst in 120 min. Further test showed that the hydrothermal process can significantly improve the photocatalytic performance of TiO 2 /AlON composite photocatalyst and its enhancement mechanism were discussed. In addition, the large-sized composite photocatalyst is easy to recover and stable to reuse with no regeneration needed. [ABSTRACT FROM AUTHOR]

The accuracy and fault tolerance of filters are directly affected by the filter architecture and algorithm, thus influencing navigation performance. The chi square detection used in the conventional reset federated filter is not sensitive to soft faults, and it is easy to cause the health subsystem to be polluted through information sharing. It is a challenge to design an adaptive reset federated filter to improve the performance of the navigation system. Therefore, taking the Strapdown Inertial Navigation System/Global Positioning System/Celestial Navigation System/Synthetic Aperture Radar (SINS/GPS/CNS/SAR) integrated navigation system as an example, an adaptive federated filter architecture for vector-formed information sharing without a fault isolation module is designed in this paper. The proposed method uses the two-state chi square detection algorithm to calculate the parameters corresponding to each state, making the state with higher accuracy obtain a greater information distribution coefficient. In addition, according to the value of vector-formed information sharing, an adaptive coefficient of measurement noise is designed. This improves the adaptability of the navigation system to soft faults. Simulation results show that the accuracy of the proposed algorithm has the same performance compared with the conventional method under normal circumstances. When the sensor has a soft fault, the adaptive federated filter algorithm proposed in this paper can adaptively adjust the distribution coefficients, eliminate the influence of the fault information and improve the precision of the navigation system. The approach described in this paper can be used in multi-sensor integrated navigation. It will have better performance in engineering applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Large-size pure AlON powder characterized by porous skeleton structure show high photocatalytic, mineralization is the main degradation style. • Both h+ and OH are the dominant reactive species for the high photocatalytic activity of AlON powder to MB. • Both high degradation efficiency of AlON to MB and high utilization of light in porous skeleton contribute to high photocatalytic activity of AlON. • The AlON photocatalysis has good stability and reusability due to the strong combination among AlON grains. • The AlON powder has excellent dispersibility and recovery for its large particle size. A large-sized (∼20 μm) pure aluminum oxynitride (AlON) powder characterized by its porous skeleton structure was synthesized by carbothermal reduction and nitridation (CRN) method using α-Al 2 O 3. The photocatalytic performance of the obtained AlON powder was studied under ultraviolet-light in methylene blue (MB) solution. In 40 ml MB solution doped with 30 mg as-synthesized AlON powder, a photogradation efficiency as high as 97% was measured after irradiating 120 min, and 80% MB was mineralized by determining the total organic carbon (TOC) in the solution, i.e., mineralization is the main degradation mode of MB in the solution due to the added AlON powder. Further radical scavenger's experiments reveal that both h+ and OH were the dominant reactive species in the photogradation process of MB by the AlON powder. It should be pointed out that the specific surface area of the obtained AlON powder is smaller than that of solid small-sized powder (∼800 nm) due to its porous skeleton structure. However, the measured photogradation efficiency of the obtained AlON powder is slightly higher than the reported value, which is mainly attributed to light reflection and scattering within its skeleton. The as-synthesized AlON powder has excellent dispersibility for its large particle size. Moreover, the obtained AlON powder also exhibits high reusability. Therefore, the obtained large-sized porous skeleton structure pure AlON powder is an efficient and promising photocatalyst. [ABSTRACT FROM AUTHOR]

An efficient condition-based predictive spare ordering approach is the key to guarantee safe operation, improve service quality, and reduce maintenance costs under a predefined lower availability threshold. In this paper, we propose a condition-based predictive order model (CBPO) for a mechanical component, whose degradation path is modeled as inverse Gaussian (IG) process with covariate effect. The CBPO is dependent on the remaining useful life (RUL), random lead-time, speed-up lead-time degree, and availability threshold. RUL estimation is obtained through the IG degradation process at each inspection time. Both regular lead-time and expedited lead-time considered in RUL-based spare ordering policy can be cost-effective and reduce losses caused by unexpected failure. Speed-up lead-time can meet the urgent needs for spare parts on site. The decision variable of CBPO is the spare ordering time. Based on the CBPO under the lower availability threshold constraint, the objective of this study is to determine the optimal spare ordering time such that the expected cost rate is minimized. Finally, a case study of the mechanical spindle is presented to illustrate the proposed model and sensitivity analysis on critical parameters is performed. [ABSTRACT FROM AUTHOR]

A novel method relying on image analysis and statistics is developed to estimate the mixing time accurately in a direct-contact heat exchanger. The critical point determination of pseudo homogeneous process impact on the accurate estimation of mixing time is investigated by proposed a three-sigma (3σ) method, which satisfies approximately normal distribution and exceeding the range of μ − 3σ occurring twice. Quantitative comparisons of the mixing time are conducted with mean value method, slope method and standard deviation method. Results show that correlation degree and correlation coefficient for the mixing time estimated by 3σ method give good agreement with the volumetric heat transfer coefficient average. Additionally, quasi steady state is quantified by time intervals between inhomogeneous time and mixing time. Experiments and simulations confirmed that neglecting critical point could result in significant errors in mixing time estimation. This method is capable of estimating the mixing time obtained by different mixing curves (e.g., slope p ) that vary at the beginning of mixing and rapidly become stabilized after fluctuations, which can be an alternative tool for practical engineering applications with good accuracy. [ABSTRACT FROM AUTHOR]

Using a pure AlON powder synthesized by carbothermal reduction and nitridation, a bimodal particle size distribution (PSD) powder was prepared by planetary ball mill, and pressurelessly sintered at 1880 °C to fabricate transparent AlON ceramics. Relative density of ≥99.72% was achieved for all the obtained AlON ceramics samples held for 90–150 min. The maximum infrared transmittance for 3 mm thickness sample was up to 81.8% (93.8% of theoretical in-line transmittance). Therefore, the holding time to fabricate transparent AlON ceramics can be shortened to 90 min or 150 min, compared to 480 min holding reported in the literature. The fast sintering of transparent AlON ceramics is a combination of fast heating (40 °C/min) and shorter holding time, and should be mainly attributed to fast surface diffusion during heating due to the bimodal PSD of fine powder and fast grain boundary diffusion during both heating and holding due to the transient bimodal grain size distribution. [ABSTRACT FROM AUTHOR]

In this paper, we present locomotion learning for an Anguilliform robotic fish using a central pattern generator (CPG) approach. First, we give the overall structure of the CPG. Different from a traditional CPG that contains only coupled oscillators, our CPG consists of coupled Andronov–Hopf oscillators, an artificial neural network (ANN), and an outer amplitude modulator. Coupled oscillators, which possess a limit-cycle character, are used to generate inputs to excite the ANN. The ANN serves as a learning mechanism, from which we can obtain desired waveforms. By inputting different signals to the ANN, different desired locomotion patterns can be obtained. Outer amplitude modulator resizes the amplitudes of the ANN outputs according to task specifications. The CPG possess temporal scalability, spatial scalability, and phase-shift property; thus, we can obtain desired amplitudes, oscillation frequencies, and phase differences by tuning corresponding parameters. By extracting the swimming pattern from a real fish and using the CPG approach, we successfully generate a new swimming pattern and apply it to the robotic fish. The new pattern reserves the swimming characters of the real fish, and it is more suitable to be applied to the robotic fish. By using the new pattern, the robotic fish can perform both forward locomotion and backward locomotion, which are validated by experiments. [ABSTRACT FROM PUBLISHER]

Abstract: This paper proposes a novel method to quantify the synergy of bubble swarm patterns and heat transfer performance in a direct-contact heat exchanger (DCHE) by using computational homology. Betti numbers are used to estimate the number of bubbles aggregating in flow patterns and to obtain the pseudo-homogeneous time. A simple linear model of a bubble swarm and the heat transfer performance of a DCHE is constructed on the basis of experimental analysis, in which a new index ( ) is defined by the Betti number average as well as the pseudo-homogeneous time. A good fitting curve between and the volumetric heat transfer coefficient average is obtained with a correlation coefficient of 0.95. A paradigm is established on the basis of this novel method for the study of flow patterns and heat transfer performance, and it offers an alternative route to explore the relationship of flow patterns and heat transfer in other heat transfer processes such as convection, multiphase flow, and turbulent flow. [Copyright &y& Elsevier]

Flow boiling heat transfer is a promising technology for thermal management. In this paper, flow boiling heat transfer characteristics in a rectangular vertical flow channel are experimentally and numerically investigated at low flow rate. Visualization results provide guidance for the prediction of flow patterns. The flow boiling correlation at low flow rates is improved with an error of less than 30%. Numerical results reveal vortices enhanced local heat transfer. Absolute vorticity is introduced to quantify the secondary flow. The results indicate that the secondary flow intensity increases with heat flux, verifying that boiling flow produces the local convection enhancement. [ABSTRACT FROM AUTHOR]

Oxygen lances are key equipment for copper converters. The effect of the lance arrangement on the mixing of a gas–slag two–phase is discussed using numerical simulation and experimental verification with a water model, and the stirring characteristics enhanced by variable–velocity blowing are explored. The results showed that the single–row lance arrangement (SA) increased the average velocity in the slag phase by 17.93% and reduced the disturbance to the metal phase by 27.78% compared to the double–row lance arrangement (DA). Compared to the constant–velocity blowing system (CSB), the sine–wave blowing system (SWB) and rectangular–wave blowing system (RWB) increased the average velocity in the slag phase by 24.03% and 13.96%, respectively, and reduced the proportion of the low–velocity area by more than 46.2%. The velocity imbalance in the SA local area enhances the mixing of the gas–slag two–phase. The variable–speed blowing improves the mass transfer and mixing effect. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study is to introduce a new technique for quantifying the efficiency of multiphase mixing. This technique based on algebraic topology is illustrated by using the hydraulic modeling of gas agitated reactors stirred by top lance gas injection and image analysis. The zeroth Betti numbers are used to estimate the numbers of pieces in the patterns, leading to a useful parameter to characterize the mixture homogeneity. The first Betti numbers are introduced to characterize the nonhomogeneity of the mixture. The mixing efficiency can be characterized by the Betti numbers for binary images of the patterns. This novel method may be applied for studying a variety of multiphase mixing problems in which multiphase components or tracers are visually distinguishable. [ABSTRACT FROM AUTHOR]

Abstract: Firstly, a numerical method for the inversion of Laplace transform is developed and its accuracy is shown through examples. Then, a state-vector equation for the dynamic problems of piezoelectric plates is deduced directly from a modified mixed variational principle for piezoelectric bodies and its exact solution for the dynamic problems of simply supported rectangle piezoelectric plate is simply given. For multilayered hybrid plates, we derive the solution in terms of the propagator matrices. The techniques accounts for the compatibility of generalized displacements and generalized stresses on the interface both the elastic layers and piezoelectric layers, and the transverse shear deformation and the rotary inertia of laminate are also considered in the global algebraic equation of structure. Meanwhile, there is no restriction on the thickness and the number of layers. As an application of the numerical inversion of Laplace transform presented in this paper, typical numerical examples of the harmonic vibration and transient response are proposed and discussed. Since the highly accurate numerical results, they can serve as benchmarks to test various thick plate theories and various numerical methods, such as the finite and boundary element methods for transient response problems. [Copyright &y& Elsevier]

Objective. The aim of the study is to investigate the clinical value of matrix metalloproteinases-3 (MMP-3) and cytokeratin 19 fragment antigen 21-1 (CYFRA21-1) combined with adenosine deaminase (ADA) in pleural effusion and serum in benign and malignant pleural exudative effusion (PEE). Methods. A total of 119 adult patients with PEE admitted in our hospital from May 2018 to October 2021 were selected. According to the patient's condition, the patients were divided into the benign group (n = 75) and the malignant group (n = 44). The levels of MMP-3, CYFRA21-1, and ADA in pleural effusion and serum were detected. The receiver operating characteristic (ROC) curve was used to analyze the individual and combined predictive value of MMP-3, CYFRA21-1, and ADA levels. Results. In the malignant group, the pleural effusion and serum MMP-3 and CYFRA21-1 levels were higher than those in the benign group and the ADA levels were lower than those in the benign group (P < 0.05). In the malignant group, the positive detection rate of pleural effusion and serum MMP-3 and CYFRA21-1 was higher than that in the benign group and the positive detection rate of pleural effusion and serum ADA were lower than that in the benign group (P < 0.05). The AUC of pleural effusion MMP-3, serum MMP-3 and the combination of them in the diagnosis of PEE were 0.764, 0.722 and 0.810, respectively. The AUC of pleural effusion CYFRA21-1 and serum CYFRA21-1 and combination of them in the diagnosis of PEE were 0.776, 0.748 and 0.822, respectively. The AUC of pleural effusion ADA, serum ADA and their combination in differential diagnosis of PEE were 0.762, 0.737 and 0.836, respectively. The AUC of pleural effusion and serum of MMP-3 and CYFRA21-1 combined with ADA for differential diagnosis of PEE was 0.923. Conclusions. The diagnostic efficacy of MMP-3 combined with CYFRA21-1 and ADA in pleural effusion and serum for benign and malignant PEE are better than single index, which has certain clinical values for the selection of early intervention scheme for PEE patients. [ABSTRACT FROM AUTHOR]

Polysaccharides have a wide range of applications due to their excellent antioxidant activity. However, the low purity and unclear structure of polysaccharides have led some researchers to be skeptical about the antioxidant activity of polysaccharides. The current reports on the structure-activity relationship of polysaccharides are sporadic, so there is an urgent need to systematically summarize the antioxidant effects of polysaccharides with clear structures and the relationships between the structures to provide a scientific basis for the development and application of polysaccharides. This paper will systematically elucidate the structure-activity relationship of antioxidant polysaccharides, including the molecular weight, monosaccharide composition, glycosidic linkage, degree of branching, advanced conformation and chemical modification. For the first time, the antioxidant activity of polysaccharides is related to their chemical structure through histogram and radar map, and further studies using principal component analysis and cluster analysis. We critically discussed how the source, chemical structure and chemically modified groups of polysaccharides significantly contribute to their antioxidant activity and summarized the current research status and shortcomings of the structure-activity relationship of antioxidant polysaccharides. This review provides a theoretical basis and new perspective for further research on the structure-activity relationship of antioxidant polysaccharides and the development of natural antioxidants. [ABSTRACT FROM AUTHOR]

The hydrogel actuated membrane in this paper is highly stretchable while having an electrically responsive output force. At a doping level of 0.6 g SA, the elongation at break of the hydrogel-driven membrane reached 3117% and the output force density reached 16.49 mN/g. In addition, the elastic modulus, tensile strength, and specific capacitance of the driving membrane reached the maximum values of 29.05 kPa, 907.24 kPa, and 452.8 mF/g at SA doping content of 0.75 g. [ABSTRACT FROM AUTHOR]

The innovative combination of additive manufacturing (AM) and continuous fiber‐reinforced polymer composites (CFRPCs) confers products with the dual advantages of integrated manufacturing and designability of properties, but lack an efficient and reliable method for property prediction. This study presents a materials informatics framework using reduced‐order models and machine learning (ML) to extract the structure–property (SP) linkages between microstructures and macroscopic elastic properties of AM‐CFRPCs. The initial step involves generating microstructural 2D cross‐sections and representative volume elements (RVEs) with random fiber and pore distributions based on the minimum potential method. Then, finite element (FE) calculations are performed on RVEs to obtain nine macroscopic elastic properties. Following that, the quantification and dimensionality reduction of the 2D cross‐sectional dataset are conducted separately using two‐point spatial correlations and principal component analysis (PCA). Finally, a Bayesian optimized composite kernel support vector regression (CK‐SVR) algorithm is used to effectively establish complex mapping relationships between the reduced‐order representations of the microstructures and the mechanical properties. Despite the reduced‐order dataset containing only 3–6 variables, the framework generates an interpretable model exhibiting excellent accuracy with all predicted R2 values surpassing 0.91. Therefore, this framework presents a prospective solution for expediting the design and optimization of AM‐CFRPCs. Highlights: A materials informatics scheme is proposed to predict the 9 elastic properties of AM‐CFRPCs.Microstructures are quantified and dimensionally reduced by two‐point statistics and PCA.SP linkages are established between 2D cross‐sections and 3D macromechanical properties.Modified CK‐SVR exhibits higher prediction accuracy compared to conventional models. [ABSTRACT FROM AUTHOR]

Background: To investigate the risk factors of pneumothorax of using computed tomography (CT) guidance to inject autologous blood to locate isolated lung nodules. Methods: In the First Hospital of Putian City, 92 cases of single small pulmonary nodules were retrospectively analyzed between November 2019 and March 2023. Before each surgery, autologous blood was injected, and the complications of each case, such as pneumothorax and pulmonary hemorrhage, were recorded. Patient sex, age, position at positioning, and nodule type, size, location, and distance from the visceral pleura were considered. Similarly, the thickness of the chest wall, the depth and duration of the needle-lung contact, the length of the positioning procedure, and complications connected to the patient's positioning were noted. Logistics single-factor and multi-factor variable analyses were used to identify the risk factors for pneumothorax. The multi-factor logistics analysis was incorporated into the final nomogram prediction model for modeling, and a nomogram was established. Results: Logistics analysis suggested that the nodule size and the contact depth between the needle and lung tissue were independent risk factors for pneumothorax. Conclusion: The factors associated with pneumothorax after localization are smaller nodules and deeper contact between the needle and lung tissue. [ABSTRACT FROM AUTHOR]

In response to the observed phenomenon of poor fluid mixing within the reactor, this study proposes a novel mixing method to enhance fluid mixing efficiency. In this study, numerical simulation and purification tests were carried out for the purification of zinc sulfate solution. Numerical simulations were conducted to compare the effects of variable-speed stirring and uniform-speed stirring on mixing efficiency, considering both momentum transfer process and mass transfer process. The purification test further demonstrated a significant improvement in the reaction rate under variable-speed stirring, as evidenced by the analysis of purification efficiency and microscopic morphology. It was elaborated that the enhancement mechanism of variable-speed stirring involved disrupting the periodic order structure in the tank, leading to the generation of a multi-scale vortex that increased stirring kinetic energy to form a shear force. This force contributed to reducing the velocity slip between the impurity ions and zinc particles, consequently decreasing reaction time and enhancing purification rate. The results indicated that sinusoidal stirring yielded the most effective mixing. When implemented in practical production settings, it enhanced dimensionless mixing efficiency by 24.83 % compared to the homogeneous stirring system. Additionally, it reduced reaction time by 15.47 % and decreased mixing energy per unit volume by 32.38 %, while simultaneously lowering energy consumption by 24.77 %. [ABSTRACT FROM AUTHOR]

Diabetes mellitus accelerates the hyperglycemia susceptibility-induced injury to cardiac cells. The activation of peroxisome proliferator-activated receptor α (PPARα) decreases ischemia-reperfusion (IR) injury in animals without diabetes. Therefore, the present study hypothesized that pemafibrate may exert a protective effect on the myocardium in vivo and in vitro. A type 1 diabetes mellitus (T1DM) rat model and H9c2 cells exposed to high glucose under hypoxia and reoxygenation treatments were used in the present study. The rat model and the cells were subsequently treated with pemafibrate. In the T1DM rat model, pemafibrate enhanced the expression of PPARα in the diabetic-myocardial ischemia-reperfusion injury (D-IRI) group compared with the D-IRI group. The infarct size in the D-IRI group was reduced following pemafibrate treatment relative to the untreated group. The disruption of the mitochondrial structure and myofibrils in the D-IRI group was partially recovered by pemafibrate. In addition, to evaluate the mechanism of action of pemafibrate in the treatment of diabetic myocardial IR injury, an in vitro model was established. PPARα protein expression levels were reduced in the high glucose and hypoxia/reoxygenation (H/R) groups compared with that in the control or high glucose-treated groups. Pemafibrate treatment significantly enhanced the ATP and superoxide dismutase levels, and reduced the mitochondrial reactive oxygen species and malondialdehyde levels compared with the high glucose combined with H/R group. Furthermore, pemafibrate inhibited the expression of cytochrome c and cleaved-caspase-3, indicating its involvement in the regulation of mitochondrial apoptosis. Pemafibrate also reduced the expression of nuclear factor-κB (NF-κB), the activation of which reversed the protective effects of pemafibrate on diabetic myocardial IR injury in vitro. Taken together, these results suggested that pemafibrate may activate PPARα to protect the T1DM rat myocardium against IR injury through inhibition of NF-κB signaling. [ABSTRACT FROM AUTHOR]

The hydrodynamic and stirring characteristics of gas-slag-copper matte three-phase in side-blowing melt pool melting were numerically simulated using a combination of the volume of fluid (VOF) model in computational fluid dynamics and the realizable k-ε turbulence model. The study obtained macroscopic flow and gas-liquid two-phase distribution information of the flow field in the melting process. It also examined the effects of isokinetic blowing and nonlinear blowing on the fluid velocity, penetration depth, gas content, and turbulent eddy volume of the flow field, and compared the results. The results indicate that, for the same total gas volume, constant velocity blowing (CVS) inadequately agitates the molten pool, resulting in a large stirring dead zone within the flow field. In contrast, nonlinear blowing enhances the fluid velocity overall. Specifically, sinusoidal variable speed blowing (SWS) and rectangular variable speed blowing (RWS) reduce the stirring dead zone area by 79 and 73.5 %, respectively. This is attributed to the increase in maximum penetration depth and slag phase gas content, as well as the decrease in gas escape during nonlinear blowing. The vortex volume over the total calculated time for the three conditions is enhanced by 6.7 and 1.1 % for SWS and RWS, respectively. Additionally, the turbulent kinetic energy of the fluids is increased by 18.7 and 17 %, respectively. [ABSTRACT FROM AUTHOR]

In this paper, image processing techniques are employed to investigate the growth and detachment characteristics of initial bubbles in vertical glass tubes. The study explores the effects of different continuous phases (water and Therminol®66), nozzle diameters, air flow rates, and continuous phase liquid levels on the detachment diameter and shape of bubbles. Furthermore, based on the detachment characteristics obtained under various experimental conditions, a novel predictive model for bubble detachment diameter is established in both water and Therminol®66. The results show that the bubble detachment diameter in the continuous phase therminol® 66 is larger than the bubble detachment diameter in water, and that the shape of the bubbles in therminol® 66 is close to spherical, with an ellipsoidal shape in water. With the increase in nozzle diameter and airflow, the bubble detachment diameter increases, and the shape is stretched in the vertical direction. With the increase in the continuous phase liquid level, the bubble detachment diameter decreases, and the shape change is not significant. In addition, the accuracy of the bubble detachment diameter prediction model was validated through experimental data. Compared with the experimental values, the average absolute errors were 5.04% and 5.11% in water and Therminol®66, respectively. This study aims to investigate the characteristics of initial bubble growth and detachment, providing valuable references for nozzle design. [Display omitted] • The growth characteristics of initial bubbles under different working fluids are studied • The shape and diameter of the bubble detachment process are studied under different operating conditions. • A new bubble detachment diameter prediction model is established [ABSTRACT FROM AUTHOR]

In this study, the uniformity factor of the temperature difference field was introduced into the direct contact heat exchanger by establishing a trace element layer model for the heat exchanger. Furthermore, the uniformities of the temperature and temperature difference field of the direct contact heat exchanger operated using a continuous heat source were analyzed. The heat exchange height was proposed,and its effects on the volumetric heat transfer coefficient and heat-exchanger efficiency were analyzed. The experimental results were consistent with the uniformity principle of the temperature difference field. [ABSTRACT FROM AUTHOR]

Some bacteria can degrade organic micropollutants (OMPs) as primary carbon sources. Due to typically low OMP concentrations, these bacteria may benefit from supplemental assimilation of natural substrates present in the pool of dissolved organic matter (DOM). The biodegradability of such auxiliary substrates and the impacts on OMP removal are tightly linked to biotransformation pathways. Here, we aimed to elucidate the biodegradability and effect of different DOM constituents for the carbofuran degrader Novosphingobium sp. KN65.2, using a novel approach that combines pathway prediction, laboratory experiments, and fluorescence spectroscopy. Pathway prediction suggested that ring hydroxylation reactions catalysed by Rieske‐type dioxygenases and flavin‐dependent monooxygenases determine the transformability of the 11 aromatic compounds used as model DOM constituents. Our approach further identified two groups with distinct transformation mechanisms amongst the four growth‐supporting compounds selected for mixed substrate biodegradation experiments with the pesticide carbofuran (Group 1: 4‐hydroxybenzoic acid, 4‐hydroxybenzaldehyde; Group 2: p‐coumaric acid, ferulic acid). Carbofuran biodegradation kinetics were stable in the presence of both Group 1 and Group 2 auxiliary substrates. However, Group 2 substrates would be preferable for bioremediation processes, as they showed constant biodegradation kinetics under different experimental conditions (pre‐growing KN65.2 on carbofuran vs. DOM constituent). Furthermore, Group 2 substrates were utilisable by KN65.2 in the presence of a competitor (Pseudomonas fluorescens sp. P17). Our study thus presents a simple and cost‐efficient approach that reveals mechanistic insights into OMP‐DOM biodegradation. [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC) is one of the most common malignancies in the world, and due to its complex pathogenic factors, its prognosis is poor. N6-methyladenosine (m6A) RNA methylation plays an important role in the tumorigenesis, progression, and prognosis of many tumors. The m6A RNA methylation regulator small nuclear ribonucleoprotein polypeptide C (SNRPC), which encodes one of the specific protein components of the U1 small nuclear ribonucleoprotein (snRNP) particle, has been proven to be related to the prognosis of patients with HCC. However, the effect of SNRPC on the tumor microenvironment and immunotherapy in HCC remains unclear. Case presentation: The HCC RNA-seq profiles in The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) databases, including 421 LIHC and 440 LIRI-JP samples, respectively, were used in this study. Both the expression of SNRPC in HCC was upregulated in the TCGA and ICGC databases compared to normal tissues. Next, the expression of SNRPC was validated as a risk factor for prognosis by Kaplan-Meier analysis and employed to establish a nomogram with T pathologic stage. By gene set variation (GSVA) analysis and gene set enrichment (GSEA) analysis, we found that SNRPC was mainly related to protein metabolism and the immune process. Furthermore, the estimation of stromal and immune cells in malignant tumor tissues using expression (ESTIMATE), microenvironment cell population counter (MCP-counter), and single sample GSEA (ssGSEA) algorithms revealed that the high-SNRPC group had a lower stromal score, lower abundance of endothelial cells and fibroblasts, and lower immune infiltration. Ultimately, a tumor immune dysfunction and exclusion (TIDE) analysis revealed that patients in the low-SNRPC group may be more sensitive to immune checkpoint inhibitor therapy. Conclusion: SNRPC could serve as a promising prognostic and immunotherapeutic marker in HCC and might contribute to new directions and strategies for HCC treatment. [ABSTRACT FROM AUTHOR]

Tumor metastasis is a major contributor to the death of cancer patients. It is driven not only by the intrinsic alterations in tumor cells, but also by the implicated cross-talk between cancer cells and their altered microenvironment components. Tumor-associated macrophages (TAMs) are the key cells that create an immunosuppressive tumor microenvironment (TME) by producing cytokines, chemokines, growth factors, and triggering the inhibitory immune checkpoint proteins release in T cells. In doing so, TAMs exhibit important functions in facilitating a metastatic cascade of cancer cells and, meanwhile, provide multiple targets of certain checkpoint blockade immunotherapies for opposing tumor progression. In this article, we summarize the regulating networks of TAM polarization and the mechanisms underlying TAM-facilitated metastasis. Based on the overview of current experimental evidence dissecting the critical roles of TAMs in tumor metastasis, we discuss and prospect the potential applications of TAM-focused therapeutic strategies in clinical cancer treatment at present and in the future. [ABSTRACT FROM AUTHOR]

• An LC-MS/MS-based MRM method was developed to measure plasma 7-KC. • Patients with sepsis and septic shock showed high plasma 7-KC expression. • High plasma 7-KC level was associated with poor prognosis in sepsis. • A prognostic model for sepsis is proposed and validated. Early evaluation of the severity of sepsis and estimation of its prognosis remains one of the main challenges in current therapeutic strategies. This study aimed to evaluate the prognostic value of plasma 7-ketocholesterol (7-KC) in sepsis. We retrospectively measured by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) the plasma 7-KC concentration in 176 patients with sepsis and 90 healthy volunteers. A multivariate Cox proportional hazard model was introduced to identify independent factors, including plasma 7-KC and clinical features, for the 28-day mortality of sepsis, and a nomogram for predicting the 28-day mortality of sepsis was established. Decision curve analysis (DCA) was performed to assess the prediction model of death risk of sepsis. The area under the curve (AUC) of plasma 7-KC in diagnosing sepsis was 0.899 (95% CI = 0.862–0.935, P < 0.001), while it was 0.830 (95% CI = 0.764–0.894, P < 0.001) in diagnosing septic shock. The AUCs of plasma 7-KC in predicting the survival of sepsis patients in the training cohort and the test cohort were 0.770 (95% CI = 0.692–0.848, P < 0.05) and 0.869 (95% CI = 0.763–0.974, P < 0.05), respectively. In addition, high plasma 7-KC expression predicts poor prognosis in sepsis. Then, 7-KC and platelet count were identified as the two factors with significant differences by a multivariate Cox proportional hazard model, and the 28-day mortality probability ranged from 0.002 to 0.985 and was assessed using a nomogram. DCA results revealed that the combination of plasma 7-KC and platelet count showed the best prognostic efficiency of the risk threshold compared to a single factor in both the training cohort and test cohort. Collectively, the elevated plasma 7-KC level is an indicator of sepsis and was identified as a prognostic indicator for sepsis patients, providing a landscape for predicting survival in early sepsis with potential clinical utility. [ABSTRACT FROM AUTHOR]

In cooling towers and condensers, accurate measurement of the void fraction in gas-liquid two-phase flow can help optimize heat transfer efficiency. By monitoring the void fraction, operational parameters can be adjusted to maximize heat exchange effectiveness. As such, the development of a technique for measuring void fraction in high-temperature and opaque containers is necessary. This paper presents a method for measuring the void fraction of the section during direct contact heat transfer using electromagnetic tomography. In order to enhance the magnetic field, a certain amount of nanofluid is introduced into the direct contact evaporator. With the aid of a self-developed EMT system, the gas and liquid phases are differentiated, ultimately yielding the section void fraction value. The final results are qualitatively consistent with three classical models for void fraction calculation. This is the first report on measuring cross-sectional void fraction in direct contact heat transfer processes using the EMT system. The findings demonstrate the feasibility of the measurement method based on EMT and provide a reference for research on high-precision and automated measurement techniques of void fraction in gas-liquid two-phase flow. [Display omitted] • The EMT technique is suitable for flow pattern detection of direct contact heat transfer processes. • The void fraction rate of EMT data has the highest correlation with the drift flow model trend. • The void fraction measured by EMT method has a consistent trend with the results calculated by three classic models. [ABSTRACT FROM AUTHOR]

The Dong-Xi-Taijinaier Salt Lake (DXTSL) of Qaidam Basin is known as one of rich lithium reserves in China. However, the source of lithium deposits in this region remains unclear. The hydrochemistry and lithium isotopes (δ7Li) of water and solid samples along the Nalenggele River catchment were studied in combination with rock leaching experiments. The results showed the hot springs in the upstream contained high content of lithium and ratio of Li × 1 000/total dissolved solids (1.5–3.5), but the lower δ7Li values (4.33‰–11.59‰), meaning that it is one important lithium sources. The leaching experiments by the rich-lithium volcanic rocks (average content of 474.7 mg/kg) showed that under temperature of 20–80 °C and long time duration (24–96 h), the concentration of lithium released by leaching of the sampled volcanic rocks increased from 0.58 to 1.49 mg/L, with the leaching rate decreasing from 0.024 to 0.015 mg/(L·h) and the corresponding lithium release rate increasing from 29% to 74%. Calculation based on water-salt balance showed that the total amount of lithium contribution from hydrothermal fluids and volcanic rock weathering is about 4.99 and 0.29 Mt since 13.1 ka, respectively. Therefore, hot springs and leaching of volcanic rocks are main contributors to lithium deposit in DXTSL. [ABSTRACT FROM AUTHOR]

This paper combines new palaeomagnetic studies, palaeontological dating, and sedimentary analyses to propose a modified stratigraphic classification scheme in the northwestern Songliao Basin, which is of great significance for stratigraphic correlation, sedimentation analysis, basinal subsidence, and oil and gas exploration. New palaeontological and palaeomagnetic evidence redefined a group of semi‐consolidated lacustrine strata, buried beneath the Quaternary Yaluhe Formation on the Western Slope of the Songliao Basin, as Late Cretaceous, not the Middle Pleistocene. The chronostratigraphic framework re‐evaluates its stratigraphic age as late Coniacian to early Campanian (Late Cretaceous), between 83 and 85 Ma. Sedimentation research from 17 boreholes on the Western Slope of the Songliao Basin displays that the semi‐consolidated strata successively experienced lacustrine and delta facies deposits. Comparison of this new stratigraphy with the Late Cretaceous sequences on the adjacent Central Depression of the Songliao Basin reveals significant variations in lithology and palynological assemblages. Three new palynological assemblages are also reported from the Late Cretaceous sequences of the Songliao Basin. [ABSTRACT FROM AUTHOR]

The poor mixing caused by zinc powder deposition in purification process is a serious problem which can't be avoided in treatment of zinc-containing solid waste. Here, to enhance the purification efficiency of zinc-containing solid waste treatment reactor, two kinds of multi-blade combined stirring systems are compared with single layer four straight-blade and double-layer straight-blade (DFB) stirring systems which are traditionally chosen by industry. This study simulated and explored the flow field characteristics and purification effects of these four kinds of stirred-tank reactor, further proposes the unit ion purification energy (UIPE) as a criterion for purification energy consumption and effect evaluation. The results show that multi-blade combined (MBC) stirring system enhances axial flow by 12.56% in water. Meanwhile it effectively inhibits the growth of isolated mixing region which scope has decreased by 56.25%. In high viscosity Carboxymethylcellulose sodium solution, the fluid axial speed can be increased by up to 1407 times with MBC. MBC can increase the purification rate by 24.79% while the UIPE decreases by 29.45% compared with DFB which is used in industrial purification process. MBC paddle has exhibited a wide range of fluid viscosity applicability and axial velocity improvement effect. The improvement increases collisions between the impurity particles and the zinc powder particles, which increased rate of substitution reactions. The application of MBC solves the purification problem in the process of treating zinc-containing solid waste. [ABSTRACT FROM AUTHOR]

The fluid in the reactor can be poorly mixed, so an eccentric impeller is proposed to improve the fluid mixing efficiency. In this investigation, numerical simulations and cadmium removal experiments for the purification of zinc sulfate solution were conducted. The effect of eccentric impellers on the purification efficiency was discussed. The mechanism of the effect of concentric and eccentric arrangement of stirring impellers on mixing in the stirred tank was elucidated. The results showed that the average axial velocity of the eccentric impeller stirring system (EIS) was 131.52% of that of the concentric stirring system (CS) and 134.23% of that of the eccentric stirring system (ES). In the purification and removal of cadmium in the zinc hydrometallurgy experiment, unit ion purification energy was introduced to quantify the energy consumed for each 1% of Cd2+ removed. The eccentric impeller shortens the reaction time by 40% and reduces the reaction energy consumption by 31.8% compared to the non-eccentric impeller. Compared to CS and ES, EIS disrupts the periodicity of fluid flow and facilitates the destruction of isolated mixing regions. EIS can enhance mechanical stirring to improve purification efficiency. [ABSTRACT FROM AUTHOR]

Abstract By formation β-SiAlON/Y-Si-Al-O-N glass-ceramic as interlayer, AlON ceramics (51.70 at.% O) were successfully joined at 1475 °C for 15 min. The effects of joining temperature on wettability of interlayer material on AlON ceramics, phase assemblages and microstructures of joints, and bending strength of the as-joined AlON ceramics were investigated. The wettability of the interlayer material on the AlON ceramics is positively correlated with joining temperature at 1300–1475 °C, and the minimum contact angle of 8° was measured at 1475 °C. Increasing joining temperature is helpful to improve the bonding strength, and the maximum bending strength of 125 MPa was achieved for the samples joined at 1475 °C, which is ~41.7% of AlON strength. The high bonding strength should be mainly attributed to the formation of high strength β-SiAlON crystalline in Y-Si-Al-O-N glasses and strong interface between AlON substrate and interlayer led by the excellent wettability of β-SiAlON/Y-Si-Al-O-N glass-ceramic on AlON ceramics. Highlights • β-SiAlON/Y-Si-Al-O-N glass-ceramic interlayer was formed at 1475 °C. • At 1475 °C, the contact angle of interlayer material on AlON is as low as 8°. • AlON was successfully joined by the glass-ceramic interlayer at 1475 °C. • For the joined sample, bending strength of 125 MPa was tested, ~41.7% of AlON. [ABSTRACT FROM AUTHOR]

In this study, the motion characteristics of bubbles in a vertical rectangular glass groove were investigated using image-processing techniques. A new metric (bubble offset) to evaluate the level of solution disturbance was proposed. The motion characteristics, such as the trajectory, bubble diameter, rise velocity, and coalescence, during the bubble rise were studied using different NaCl concentrations and airflow rates. The functional relationship of the bubble diameter and velocity with height was obtained by least-squares fitting (correlation coefficient R2 ≥ 95%), and fits the power-law distribution. The results showed that the bubble motion characteristics were positively correlated with the airflow rate and negatively correlated with the NaCl concentration in the solution. The solution disturbance was closely related to the bubble offset, and the size of the bubble offset can be used to characterize the degree of the solution disturbance. The disturbance of the solution affects the bubble trajectory, rising velocity and coalescence. The bubble offset changed periodically with height, and its functional relationship was obtained. The accuracy of the functional relationship was verified using experimental data. The study of bubble motion characteristics is crucial for understanding phenomena such as heat and mass transfer and multiphase cooling. [ABSTRACT FROM AUTHOR]

The transformation of gramine and its analogues represents an important strategy in organic chemistry. Here, we report an acid and DCE co‐promoted phosphonation of gramine and its analogues using trialkyl phosphites as nucleophilic reagents. This reaction avoided the use of stoichiometric alkylation reagents, PBu3 (Tributyl phosphine) and noble metal catalyst. Except for the tertiary amino group in indoles, the primary amino and secondary amino groups, which the previous work did not mentioned were explored. [ABSTRACT FROM AUTHOR]

• Tilted tube bundle pool boiling was studied. • The boiling heat transfer coefficient is affected by the inclination angle and the heat flux of the lower tube. • The mechanism of enhanced heat transfer essence is described from the perspective of wall temperature uniformity. • The newly constructed model successfully predicted the boiling heat transfer coefficient with a maximum error of 13% or less. • The simulation verified the experimental results, and the error of both is within 10%. Examination of bubble nucleation and detachment mechanisms in tubular pool boiling is important for designing passive heat exchangers in nuclear power plants. This study investigated the heat transfer characteristics of pool boiling in deionized water using an experimental method combined with a simulation approach. Based on the change in the experimental conditions, a prediction model of the heat transfer coefficient was constructed, and the model was verified using experimental data with a maximum error of 13%. The effects of different inclination angles and lower tubes (two rods: the upper and lower tubes) on the boiling heat transfer, wall temperature uniformity, and bubble departure diameter of the tubular bundle pool were studied. The results showed that an increase in the heat flux of the lower tube and a decrease in the inclination angle increased the heat transfer coefficient of the upper tube. The main reason for the enhanced heat transfer in the upper tube was the convective flow and liquid stirring caused by the rising bubbles in the lower tube. The boiling process changed from natural convection to forced convection, which strengthened the heat transfer in the upper tube. Finally, the simulation was verified using the volume of fluid (VOF) and Lee phase change model, and the results agreed with the experimental results (within 10% of the maximum error). [ABSTRACT FROM AUTHOR]

The measurement of the two-phase contact area is very important to determine the heat transfer coefficient in the process of direct contact heat transfer, but the direct measurement of the two-phase contact area is a difficult problem. The experiments are carried out utilizing a cylindrical Perspex tube of 100 cm in total height and 15 cm inner diameter. The active column height throughout the experiments is taken to be equal to 50 cm. Liquid Therminol®66 with four different initial temperatures (50 °C, 60 °C, 70 °C and 80 °C) is used as a continuous phase, while liquid R245fa at a constant temperature of 23 °C is used as a dispersed phase. In this paper, the empirical correlations between bubble growth and local convection heat transfer coefficient are obtained through modeling and measurement, and its correctness is verified by experiments. The results show that the bubble diameter is positively correlated with continuous phase temperature, flow rate ratio, and height, but the local convection heat transfer coefficient is negatively correlated with continuous phase temperature, flow rate ratio, and height. At the same time, it is found that the maximum error between the actual bubble diameter and the theoretical bubble diameter is 7%, and the error between the heat flux calculated by the local convection heat transfer coefficient and the actual heat flux is within 10%. This study provides theoretical guidance for an in-depth understanding of the direct contact heat transfer process and the development of high-efficiency waste heat recovery systems. [ABSTRACT FROM AUTHOR]

This investigation proposes a dual-camera positioning method and the average distance in the cube (AD-Cube) method to explore the effect of three-dimensional (3D) spatial multiphase stirring. The 3D trajectories of the tracer ball were reconstructed in the stirring system using a dual-camera positioning method. The AD-Cube method for calculating the mixing uniformity within the cube region was proposed and verified by rigorous and valid numerical validation (the standard reference value was approximately 0.6617). The negative correlation coefficient between conductometry and the AD-Cube method for the evaluation of the mixing effect was −0.9118. The stirring region was equally divided into several 3D blocks, and the relationship between the whole and local was elaborated to provide more accurate information for the 3D uniformity metric. Moreover, the volume of the stirring dead zone was estimated by discrete blocking, and the influence of the stirring paddle height from the bottom and agitating motor speed on the stirring effect was studied. This study provides a theoretical basis for optimizing the parameters of a 3D stirring system, designing chemical reactors, and measuring and evaluating the 3D uniformity of stirring systems. [Display omitted] • The proposed method is based on dual-camera positioning and computational geometry. • The 3D uniformity of stirring system is characterized by the novel method. • Effectiveness of the novel method is verified on both numerical and experimental. • Evaluation indicator is established to evaluate the 3D stirring efficiency. • The method can be used in engineering fields of evaluation of 3D uniformity. [ABSTRACT FROM AUTHOR]