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LiH is valued by researchers and engineers for its high-temperature resistance, high strength, high hydrogen storage capacity of up to 12.6 wt%, and high neutron absorption cross section. However, sintering and application of this material are difficult. Lithium hydride is a highly effective neutron shielding material. The neutron shielding ability of lithium hydride is directly affected by the homogeneity of the total amount and distribution of hydrogen. The heat migration of hydrogen reduces the neutron shielding effectiveness of lithium hydride. It is critical to forecast H's diffusion behavior. The diffusion coefficient is a critical metric for determining the diffusion efficiency. As a result, the stability, electronic structure, and bonding properties of LiH, LiOH, and H entering the tetrahedral interstitial sites of LiH were calculated using first principles based on density functional theory (DFT). The elastic modulus of the system was also examined to find the lowest thermal conductivity, and some thermodynamic parameters were derived by calculating LiH phonons. Finally, static calculations were used to determine the diffusion coefficient and diffusion activation energy of H in the LiH solid solution. The results revealed that the addition of H altered the characteristics of the LiH semiconductor, giving it metallic features. The lowest thermal conductivity of the LiH system was 2.9. W·m−1 K−1. The diffusion coefficient was D = (2.638 × 10 − 2 c m 2 / s ) exp ( − 5.811 × 10 − 3 cal / K B T). The activation energy for diffusion was 0.252 eV. The diffusion coefficients, elastic constants, and lattice parameters all corresponded well with previously published results. The density functional theory was employed to study the material's system energy and electrical structure, and the microscopic migratory behavior of hydrogen was predicted theoretically. The calculation of the lowest thermal conductivity provided a reference for the screening of ceramic materials. • First-principles calculations can allow for a better understanding of the H diffusion mechanism in LiH materials. • Diffusion from the LiH surface to the interior of the material requires greater energy drive. • The introduction of interstitial H atoms can make LiH have metal properties. • The lowest thermal conductivity of the material can provide a reference for the selection of ceramic materials. • LiOH is more thermally stable than LiH. [ABSTRACT FROM AUTHOR]

Lithium hydride (LiH) is an important hydrogen storage, heat storage and neutron shielding material. When used in neutron shielding structure, its size and strength have certain requirements, which would be met by LiH ceramics. However, it fails easily during sintering due to severe thermal stress and high brittleness. In this study, the influences of the dimension, furnace temperature cooling rate, and convection condition on the mechanical behavior were systematically examined. The results indicated that larger dimensions and faster furnace temperature cooling rates resulted in higher maximum stresses. Furthermore, convection was beneficial for reducing the thermal stress. Accordingly, a process-based failure assessment diagram method was proposed to evaluate the safety of LiH ceramics, and a bilinear precise temperature control approach was proposed. Based on this method, the tube thickness was increased by 25 % and the cooling time was reduced by 32 % compared to those using linear temperature control in an example. The conclusion and method could be applied to optimize the temperature control for more practical large-dimension sintering. [ABSTRACT FROM AUTHOR]

Simple Summary: Anteon Jurine, 1807 is a cosmopolitan genus of dryinid parasitoids that attack leafhoppers. Sexual dimorphism is extreme in Anteon species, rendering the morphological taxonomy of these parasitoids difficult. This paper employs an integrated taxonomic approach that combines morphology with DNA barcoding to investigate the species delimitation of Anteon from China. Of the twenty-nine morphospecies examined, twenty-four species were identified as previously known species and five were described here as new species. The sexual association of six species was confirmed by DNA barcoding, indicating that such tools are powerful to tackle the taxonomic challenges in parasitoids with sexual dimorphism. Species of Anteon Jurine, 1807 are a large group of parasitoids attacking leafhoppers, which are important insect pests. Despite their great potential in pest biological control, the taxonomy and biology of these parasitoids are far from clear. Sexual dimorphism is extreme in Anteon species and has hampered the taxonomy of these parasitoids, resulting in many species described based on a single sex. In this paper, we employed an integrated taxonomic approach for delimitating species, combining morphological examinations with DNA barcoding, to investigate Anteon species from China. In total, 53 COI sequences representing 29 species of Anteon were obtained and analyzed. On the basis of both morphology and DNA barcoding, five new species of Anteon were discovered and described: A. clariclypeum sp. nov., A. maguanense sp. nov., A. parafidum sp. nov., A. shaanxianum sp. nov., and A. shandonganum sp. nov. The neotype of A. claricolle Kieffer is designated. The sexual association of six species was confirmed by DNA barcoding, which led to the synonymy of Anteon liui Xu, Olmi & He 2010, new syn., under Anteon meifenganum Olmi, 1991. Keys to species of Anteon from the Oriental and Eastern Palaearctic are updated to contain the five new species. Our study demonstrates that DNA barcoding is a potent tool for tackling the taxonomic challenges in parasitoids with extreme sexual dimorphism. [ABSTRACT FROM AUTHOR]

The estimation of the maximum displacement of steel beams with hexagonal web openings under impact loads is crucial for the anti-impact design of structures. The dynamic characteristics are complex, and the maximum displacement can be obtained experimentally, although the time cost, and expense of such experiments are high. In this context, a 6-5-1 artificial neural network model based on the Levenberg-Marquardt backpropagation algorithm was developed, incorporating 5-fold cross-validation techniques. Due to limited experimental data, 324 high-precision finite element models were created in bulk using Python-based ABAQUS software scripts to provide additional numerical data, and 26 specimens were designed for drop hammer tests to validate the finite element models. The artificial neural network model on the test data yielded a mean squared error of 0.0268, a mean absolute error of 0.0014, and a coefficient of determination value of 0.9806, with samples having an error of less than 10% comprising 77.16% of the total samples. Using Garson's algorithm, the contribution of input features was estimated, and a full parameter analysis of the proposed model was conducted. The results indicate that the most significant factor is the impact mass, which accounts for 37.58%. When the impact mass increased from 530 kg to 630 kg, the maximum displacement of Q235 surged by 93.75%. The factor with the least impact is the opening spacing, accounting for 2%, with an average increase in maximum displacement of only 3.45%. Finally, ANN-based equations that can be used as design tools are established. [ABSTRACT FROM AUTHOR]

The superfamily Platygastroidea (Hymenoptera: Proctotrupomorpha) is a diverse group of parasitoid wasps that are parasitoids of nine orders of insects as well as spiders. They appear to show a clear pattern of host group specificity among genera. A robust phylogeny is essential for devising a stable and informative classification and understanding the pattern of the shifts to parasitize new host groups. We conducted phylogenetic analyses of Platygastroidea based on four molecular markers (18S, 28S, COI and wingless) and 119 morphological characters, and a phylogenomic analysis of a subset of taxa based on 4371 single‐copy, protein‐coding genes. The four‐gene analyses, both with and without morphological data, robustly recovered some well‐established groups, e.g., Platygastridae (in its traditional sense), Scelionini, Teleasinae and Telenominae, as well as some novel patterns of relationship. The ground‐plan host for the superfamily are the eggs of Orthoptera, with multiple shifts to attack new host groups. The phylogenomic analysis of a subset of taxa recovered a clear pattern of relationships for the backbone of the superfamily with maximal bootstrap support. Based on the combination of these two approaches, we present a revised classification for Platygastroidea and recognize the following eight families: Geoscelionidae stat.rev., Janzenellidae fam.nov., Neuroscelionidae fam.nov., Nixoniidae stat.rev., Platygastridae stat.rev., Proterosceliopsidae†, Scelionidae stat.rev. and Sparasionidae stat.rev. This published work has been registered on ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:480936B5‐3C2C‐4B6A‐B273‐10DCBF9005E9. [ABSTRACT FROM AUTHOR]

Simple Summary: Little is known about the molecular data and phylogenetic relationships of scoliid wasps. In this study, we determined 10 mitochondrial genomes representing eight genera in two tribes of the family Scoliidae distributed in China, compared and analyzed all Chinese genus representatives for general features and rearrangement. Phylogenetic relationships between them were inferred using MrBayes and IQtree based on four data matrices. Gene rearrangement was chosen for ancestral state reconstruction. Our results support most of the relationships between genera and tribes of Scoliidae in former morphological studies except for the Colpa group, which is proved to be closer to Scoliini based on our genome features, phylogenetic analyses and some morphological evidence. Scoliidae, also known as scarab hunters or flower wasps, are important in the biological control of scarabs and for pollination. Mitogenomic and phylogenetic studies are rare for this group. In this study, 10 mitochondrial genomes representing eight genera in two tribes of the family Scoliidae were determined. The general features and rearrangements of the mitochondrial genomes for 15 Scoliidae species representing all genera distributed in China were described and compared and the phylogenetic relationships among them were inferred using MrBayes and IQtree based on four data matrices. Most sequences of Scoliidae have one extra trnM gene. Species belonging to Campsomerini have lower A + T content than all Scoliini species except for Colpa tartara in this study. The AT-skew is positive in 7 out of 15 species. All 15 Scoliidae sequences have similar conserved gene arrangements with the same arrangements of PCGs and rRNA genes, except for Campsomeriella annulata. The tRNA genes have the highest frequency of rearrangement, and C. tartara is always rearranged as in its Scoliini counterparts. Our phylogenetic results support most of the relationships between genera and tribes of Scoliidae in former morphological studies. However, Colpa tartara is proved to be closer to Scoliini according to genome features, phylogenetic analyses and some morphological evidence, which challenges the former attribution of the Colpa group. [ABSTRACT FROM AUTHOR]

To investigate the shear resistance performance of web-opening high-strength steel beams (WOHSSBs) under impact loads, falling-hammer impact tests were performed, focusing on the impact energy, inter-opening space, and opening height. The test results showed that the WOHSSBs under impact loads exhibited two local deformation patterns: the Vierendeel mechanism and the out-of-plane lateral buckling deformation of the web. Five different stiffening methods were used to improve the shear resistance performance of WOHSSBs, and numerical simulations were performed to analyze the shear resistance performance under different stiffening methods, revealing that applying horizontal vertical composite stiffeners and opening flange stiffeners were more effective in improving the shear resistance performance of WOHSSBs than the other stiffening methods. Additionally, enhancing the constraints at the edge of the openings can effectively improve the shear capacity of WOHSSBs under impact loads. Finally, formulas for the ultimate shear capacity of WOHSSBs with and without stiffening ribs under impact loads for various opening-height ratios. • This study conducted falling-hammer tests and finite element methods to study the shear performance of web-opening high-strength steel beams (WOHSSBs) under impact loads. • Comparative examination of the shear performance of WOHSSBs under different influencing parameters for five different stiffening methods. • The employment of horizontal vertical composite stiffeners and opening stiffeners proved to be more effective in enhancing the shear performance of WOHSSBs than other stiffening methods. • Propose formulas for calculating the ultimate shear capacity of WOHSSBs with and without stiffening ribs under impact loads for various opening-height ratios. [ABSTRACT FROM AUTHOR]

This paper investigates the performance of high-strength steel beams with web openings (HSSBWOs) under impact by methods of tests and finite element. Based on the experimental data of 10 specimens, which were made of high-strength steel Q550D, and the effects of impact energy and web opening forms on the impact behavior of HSSBWOs are investigated emphatically. In particular, two specimens made of steel Q235D were used to study the differences in impact behavior from HSSBWOs. The test results reveal that the high-strength steel beams with circular web openings (HSSBCWOs) have better impact resistance than the high-strength steel beams with hexagonal web openings (HSSBHWOs), and the HSSBWOs have better impact resistance than the normal-strength steel beams with web openings (NSSBWOs). Moreover, HSSBWOs has excellent abilities to absorb energy, the average energy absorption rate of HSSBHWOs and HSSBCWOs is 95.78% and 93.55%, respectively. In addition, finite element models that can accurately predict the dynamic responses of HSSBWOs under impact load are established to analyze the shear force evolutions, as well as investigate the differences of impact behavior between steel beams with a variety of web openings forms. The results show that the shear force distribution ranges of HSSBCWOs are larger than that of HSSBHWOs at the time when impact force reached peak value. The HSSBWOs can sustain more impact load with the web opening shape that closer to the circle. The solid webbed steel beam (SWSB) has better impact resistance than the steel beams with web opening (SBWO). • This study conducted drop hammer tests and finite element methods to investigate the dynamic response of Q550 high-strength steel beams with web openings (HSSBWOs) subjected to impact loads. • The effects of impact energy and the web opening form on the dynamic responses of HSSBWOs were analyzed. • A finite element model was developed to analyze the post-impact internal forces of HSSBWOs and the differences of impact behavior between steel beams with a variety of web openings forms. [ABSTRACT FROM AUTHOR]

A drop-weight impact testing machine was used to conduct an impact test on 9 specimens in order to examine the impact resistance of high-strength steel beams with circular web openings (HSSBCWO). The experimental results indicated that the dynamic response of HSSBCWO is significantly affected by the change of impact energy and opening height. A coefficient β is proposed to assess the severity of localized deformation in HSSBCWO, and the range of β values for the specimens of test are found to be approximately between 0.5 and 0.8. Within the range of impact energy designed for the experiment, HSSBCWO primarily absorbed energy through localized plastic deformation. A finite element model which can predict the dynamic response of HSSBCWO under impact load is established. The results show that the optimal ratios of opening height to beam height and spacing between openings to beam height for the HSSBCWO are determined to be 0.50 and 0.93, respectively. Furthermore, a damage evaluation system for HSSBCWO under impact load was established, utilizing the ratio of mid-span residual displacement to calculated beam span D r / L 0 as the damage assessment index, with impact energy, opening height, and spacing between opening as the main control parameters. • This study conducted impact test to investigate the dynamic response of High-strength steel beams with circular web openings (HSSBCWOs) under impact load. • Collect the impact force, displacement, and high-speed image during impact. • The use of high strength steel can make the steel beam with circular web opening (SBCWO) obtain good impact resistance. • A coefficient β is proposed to assess the severity of localized deformation in HSSBCWO. • HSSBCWO has a good absorption effect on impact energy. • A damage assessment system applicable to HSSBCWO was established. [ABSTRACT FROM AUTHOR]

• The mechanical behavior of CFST column subjected to lateral impact was studied by drop hammer test and finite element method. • Numerical model was reasonable for investigating the stress development, damage, and inertial force of the CFST column. • The effects of the impact velocity, impact mass, cross-sectional steel ratio, and boundary conditions on the inertial force of the CFST column were analyzed. • Based on a research of the inertial force at the peak impact force, a simple mechanical model of the inertial force was built. The mechanical behavior of concrete-filled steel tube (CFST) subjected to lateral impact was studied by drop hammer test and finite element method (FEM). Lateral deformation occurred when the midspan of CFST was impacted by a drop weight. Two plastic hinges were formed in the mid-span and near the fixed support, respectively. The numerical and experimental results were compared to ensure that the numerical model was reasonable for investigating the stress development, damage, and inertial force of the CFST column. The effects of the impact velocity, impact mass, cross-sectional steel ratio, and boundary conditions on the inertial force of the CFST column were analyzed. During the impact process, the maximum stress was at the steel tube part of the impact location and the fixed support, while the other parts were still in the elastic or elastoplastic stages. The region under restraint at the fixed end of the CFST column exhibited the first signs of concrete core damage under tension, followed by the region near the location of the impact at midspan. At the peak impact force (F p), the impact velocity had a considerable influence on the distribution of inertial force of CFST, while the impact mass and cross-sectional steel ratio had no discernible impact on the inertial force at the F p , and boundary conditions had little impact on the distribution of inertial force. Based on a research of the inertial force at the F p , a simple mechanical model of the inertial force was built. [ABSTRACT FROM AUTHOR]

Due to its lightweight and strong neutron shielding, lithium hydride (LiH) is a potential candidate shielding material in small modular reactors (SMR). However, the preparation of large-sized, thick-walled lithium hydride blocks using conventional methods faces challenges such as slow ramp-up rates, excessive grain growth, and large temperature gradients, and microwave sintering technology may offer a good solution to the above problems. The material's dielectric spectrum properties and thermal conductivity parameters were evaluated using first principles calculations, which may serve as a reference for exploring the lithium hydride microwave sintering mechanism. The static dielectric constant of lithium hydride was 4.4 and the optical dielectric constant was 1. The thermal conductivity at 300 K was 15.88 (W m−1 k−1), which was consistent with the existing experimental value of 14.7 (W m−1 k−1). Furthermore, we discussed the effect of temperature and vacancy defects on the dielectric temperature spectral properties of the material. The results showed that while the thermal conductivity decreased with increasing temperature, and the phonon thermal conductivity of LiH (vacancy defects) decreased. The presence of a vacancy defect in LiH leads to an increase in the number of free electrons near the Fermi level, thereby enhancing its electron thermal conductivity. The optimal sintering frequency of LiH with vacancy defects also decreased. [Display omitted] • The dielectric temperature characteristics of the material resolved the sintering effect. • Thermal conductivity could be accurately evaluated by considering heat expansion. • Vacancy defects (VD) could improve the thermal conductivity of LiH. • VD reduced the frequency range of dielectric dissipation and increased the EELS. • This study could serve as a reference for determining the external electromagnetic field frequency. [ABSTRACT FROM AUTHOR]

A drop-weight impact testing machine was used to conduct an impact test on 15 specimens in order to examine the impact resistance of high-strength (HS) steel beams with hexagonal web openings (SBHWO). The test findings demonstrate that as steel strength increases, maximal impact force and impact platform value rise, while maximum displacement, residual displacement, beam-end rotation, reduction ratio of opening area, and energy absorption ratio decrease. The use of high-strength steel can significantly improve the impact resistance of the SBHWO. When steel Q235 was lifted to steel Q550, the average increase of impact peak and impact platform value was 17.94% and 90.80%, respectively, and the average reduction range of maximum displacement and residual displacement in the span was 45.36% and 55.30%, respectively. After steel Q550 was upgraded to steel Q690, the improvement effect of impact resistance is small. Empirical equations of the relationship between impact energy，steel strength and dynamic responses were established. • This study conducted impact test to investigate the dynamic response of High-strength steel beams with hexagonal web openings (HSSBHWO) under impact load. • Collect the impact force, displacement, and high-speed image during impact. • The use of high-strength steel can significantly improve the impact resistance of the HSSBHWO. • Steel beam with hexagonal web openings (SBHWO) has a good absorption effect on impact energy. • Establishing the empirical relationship between impact energy，steel strength and dynamic responses can predict the dynamic responses of SBHWO. [ABSTRACT FROM AUTHOR]

In this work, the viscoplasticity and creep behavior for modified 9Cr-1Mo and 316 stainless steels were investigated. Based on the absolute reaction rate theory, a unified constitutive model incorporating internal state variables was proposed to characterize the evolution of the back stress. Also, the model was implemented by the ABAQUS system with the semi-implicit stress integration. Compared to the experimental data, the results demonstrated that the proposed approach could effectively simulate the cyclic softening and hardening behavior for such structural steels. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel aromatic polyimine CANs were prepared with aromatic compounds. • These CANs demonstrated superior water and heat resistances. • These CANs showed excellent chemical resistance and mechanical properties. • These CANs perfectly maintained their dynamic behavior characteristics. • This study provides a new method for improving polyimine's comprehensive performance. Polyimine covalent adaptable networks (CANs) exhibit several dynamic characteristics (such as recyclability and reprocessability) that are beneficial for compensating for the disadvantages of traditional petroleum-based synthetic thermosetting resins, and are therefore suggested as potential substitutes for environmentally unfriendly resins. However, owing to the lack of sufficient stability of imine bonds and their linked molecular chains, most polyimine CANs do not exhibit superior properties in applications with high stability requirements, such as strong water resistance, high heat resistance, and excellent mechanical strength. In this study, we designed and synthesized a new class of aromatic petroleum-based polyimine CANs to improve the stability of imine bonds and molecular chains employing the conjugation effect of the two benzene rings to C=N and aromatic structures. In contrast, these CANs simultaneously demonstrate superior water resistance (water absorption: 0.14–0.15%) and heat resistance (5% weight loss (T d5%): 434–441 °C; glass transition temperature (T g): 217–239 °C) than that of previously reported polyimine CANs (water absorption: 0.90–90%; T d5% : 200–348 °C; T g : 47–215 °C). They have outstanding mechanical properties that are almost unaffected by adsorbed water. Meanwhile, the resins exhibited remarkable resistance to ordinary acids, bases, oxidants, salts, solvents, and oils, except for several special solvents. In addition, like other polyimine CANs, they maintain their dynamic behavior characteristics, including degradability, recyclability, malleability, reprocessability, and rehealability. This study provides a new method to improve the comprehensive performance of polyimine CANs through reasonable molecular structure design. [ABSTRACT FROM AUTHOR]

The objective of this work is to improve the interlaminar shear strength (ILSS) of the composites by surface coating of carbon fibers (CFs). The effect of polypyrrole (PPy) coating on CF composites was studied. The morphologies of untreated and treated CFs were characterized by scanning electron microscope and x-ray photoelectron spectroscopy, respectively. Surface analysis showed that the surface of CFs chemisorbed oxygen-containing groups and active carbon as well as increased wettability after surface treatment with PPy. The mechanical properties show that the treated CF composites can possess excellent interfacial properties with polytetrafluoroethylene matrix, and ILSS of the composites is up to 106 MPa. [ABSTRACT FROM AUTHOR]

A multi-parameter sensitivity analysis method was proposed based on Latin hypercube sampling and the rank correlation method. The general genetic algorithm was improved by incorporating a niche parallel algorithm, suspicious peak point judgment, and a local search strategy, and both the improved genetic algorithm and multi-parameter sensitivity analysis method were implemented through C++ programming. The hydrogen pressure-composition isotherm (PCT curve) was found to play an important role in the study of hydrogen storage properties of metallic materials, and its reaction enthalpy change term was widely replaced by a power series form of smoothing. Based on the improved multi-parameter sensitivity analysis method, the effects of the range of parameter values and the number of samples on sensitivity were investigated, where the sensitivity ranking of the 10 parameters in the classical model was obtained. In addition, the equilibrium hydrogen pressure expression models of the highest order i of the power series from 3 to 9 were developed. The influence of the highest order on the optimization of multi-parameter identification was compared using an improved genetic algorithm, and we concluded that the eighth order polynomial model had the optimal convergence and fitting effect. Based on the inspiration of the function trend shape, two innovative forms of the PCT model power series were proposed in this work. Combined with typical examples, three high-order models were fully evolved, and a better power series form was obtained compared to the traditional model. • Two improved approaches were used to smooth-fit the hydrogen pressure-composition isotherm (PCT curve). • Based on the inspiration of function trend shape, two innovative forms of the PCT model power series were proposed. • The influencing factors of parameter sensitivity of PCT curve were determined and the applicable conditions were discussed. • The PCT curve optimized by intelligent algorithm was in good agreement with the experimental value. • An evolution process of one new power series form was more excellent than the classic one. [ABSTRACT FROM AUTHOR]

Applied to a hydrogen absorption-desorption cycle, the hydrogen storage bed will experience higher exchange temperatures and variety of mechanical load. Due to the complex structure of the double-layered annulus metal hydride bed and the importance of thermal stress on the failure of a metal hydride bed, the numerical modeling of its hot spot stress was carefully carried out. Moreover, in this paper, an analysis method considering the limit failure mode condition is proposed to deal with the stress analysis in the process of hydrogen absorption and desorption. According to the proposed analysis method, the maximum stress of thermal-structural coupling in the process of hydrogen absorption occurs at about 1/3 along the diameter direction and at the geometric mutation of the connection between the cooling pipe and the main body of the hydrogen storage bed in the process of hydrogen desorption. Apart from that, the hydrogen storage bed is also subjected to thermal-mechanical fatigue by the iterative process of absorption and desorption, and its operating temperature range is in the thermal creep temperature region. Based on the distribution of the stress and temperature, evaluation hot sites were selected and the ASME-NB and ASME-NH codes were used to evaluate fatigue and fatigue creep, respectively. The evaluation showed that the fatigue damage generated during its service life is small, while the creep damage is relatively large and the total damage generated during the service life of the hydrogen storage bed is within the safe range. Aiming at the structure and complex process of a double-layer hydrogen storage bed, creep and fatigue evaluation methods are proposed, various failure modes of hydrogen storage bed are highlighted, and the relationship between process parameters and life is established. [ABSTRACT FROM AUTHOR]

Piperacillin is commonly used off‐label in neonates for the treatment of bacterial infections. This study aimed to assess a dried blood spots (DBS)‐based microsampling strategy for supporting population pharmacokinetics and treatment optimization of piperacillin in Chinese neonates. DBS samples from neonatal patients were collected at predefined intervals. Drug blood concentrations were quantified using a validated ultra‐high‐performance liquid chromatography‐tandem mass spectrometry method. A population pharmacokinetic model was developed using a nonlinear mixed‐effects modeling approach. The pharmacokinetic/pharmacodynamics (PK/PD) target was 75% of the time with the unbound drug plasma concentration above the minimum inhibitory concentration (fT>MIC), with a toxicity threshold of unbound drug plasma trough concentration above 64 mg/L. A total of 45 piperacillin samples from 24 neonates were collected. The pharmacokinetics of piperacillin was described using a one‐compartment model with postmenstrual age (PMA) as the most significant covariate on clearance. Simulations showed that dosing regimens achieving >90% PK/PD target attainment with <10% risk of possible toxicity were: PMA 33‐35 weeks (50 mg/kg q12h), 35‐37 weeks (50 mg/kg q8h), and 37‐41 weeks (50 mg/kg q6h). In conclusion, Using DBS sampling, we developed a population pharmacokinetic model of piperacillin in Chinese neonates, incorporating PMA to determine optimal dosing regimens. [ABSTRACT FROM AUTHOR]

To improve the air humidification capacity of polyvinylidene fluoride hollow fiber membranes, surface coating method is applied to superhydrophobicly modify the hollow fiber membranes to achieve high performance. Chemical bonds were used as a bridge to connect the membrane and the coating. Silica is loaded on the membrane surface firstly, and then, polyhedral oligomeric silsesquioxane (POSS) and polydimethylsiloxane containing mercapto groups (PDMS) were introduced on the surface of the membrane through the click reaction to build a superhydrophobic surface with a reentrant structure. Then the effect of the content of POSS and PDMS on the humidification performance was explored. The superhydrophobic membrane coated with SiO2-PDMS-POSS was obtained, and the surface contact angle was 156.2°. The modification process occurs only on the outer surface of the hollow fiber membrane and not in the cross-sectional pores of the fiber. Besides, the coating of the modified superhydrophobic membrane exhibited excellent mechanical stability. The reentrant structure produced by nano-SiO2, POSS and the low surface energy of PDMS together gives the composite membrane superhydrophobic characteristics. The results of the humidification experiment shows that the humidification efficiency increased from 48.26 to 58.21%. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study, we sequenced two mitochondrial genomes of Dendrocerus (Hymenoptera: Megaspilidae) to analyze the mitochondrial genomic features of Dendrocerus and provide new molecular data for phylogenetic studies of Evaniomorpha. The phylogenetic results revealed that Evaniomorpha is not a monophyletic group, which is also supported by the PBD (Pairwise breakpoint distances) values. Additionally, Ceraphronoidea is a monophyletic group and is a sister to Aulacidae + Gasteruptiidae. Furthermore, specific primers MegaF/MegaR were designed for Megaspilidae based on the "conserved regions" of COX1 sequences. They exhibited a good amplification efficiency of 60% for the genus Dendrocerus. This study provides new molecular data for phylogenetic studies of Evaniomorpha, further offering the possibility of solving a controversial problem in the phylogeny of Evaniomorpha and providing a solution to the problem of difficult amplification of the COX1 gene in Ceraphronoidea. In Hymenoptera, the monophyly of Evaniomorpha has been the focus of debate among different scholars. In this study, we sequenced two mitochondrial genomes of Dendrocerus (Hymenoptera: Megaspilidae) to analyze the mitochondrial genomic features of Dendrocerus and provide new molecular data for phylogenetic studies of Evaniomorpha. The mitogenome sizes of D. bellus and D. anisodontus were 15,445 bp and 15,373 bp, respectively, with the trnG of D. bellus missing. The nucleotide composition was significantly biased toward adenine and thymine, with A + T contents of 81.2% (D. bellus) and 82.4% (D. anisodontus). Using Ceraphron sp. (Ceraphronidae) as reference, the Ka/Ks values of NAD4L and NAD6 in D. anisodontus were both greater than one, indicating that non-synonymous mutations are favored by Darwinian selection, which is rare in other hymenopteran species. Compared with Ceraphon sp. gene order, nine operations were identified in D. anisodontus, including four reversals, four TDRLs (tandem duplication random losses) and one transposition, or four reversals and five TDRLs. Phylogenetic analysis of 40 mitochondrial genomes showed that Evaniomorpha was not a monophyletic group, which was also supported by the PBD values. Ceraphronoidea is a monophyletic group and is a sister to Aulacidae + Gasteruptiidae. Based on the conserved region of the newly sequenced mitochondrial genomes, a pair of specific primers MegaF/MegaR was designed for sequencing the COX1 genes in Megaspilidae and a 60% rate of success was achieved in the genus Dendrocerus. [ABSTRACT FROM AUTHOR]

In this work, we established a three-dimensional coupled heat transfer model to evaluate the heat transfer during the hydrogenation reaction process in a uranium-based hydride bed. We constructed numerical simulations combined with the proposed model using Fluent to systematically investigate the influence of structure configurations, cooling media, and material thermal–physical properties on the thermal performance. Importantly, because the coolant temperature and the bed wall continuously changed during the hydrogen recovery process, the solid–liquid interface temperature had to be considered for an efficient thermal design of the bed wall cooling system. Accordingly, a coupling iteration algorithm was developed to improve the temperature prediction accuracy. In addition, we systematically investigated the effects of layer thickness, thermal conductivity, and cooling systems on the heat transfer behavior. The results demonstrated that reducing the hydride layer thickness, mixing the metal hydride bed with high-conductivity materials, increasing the cooling agent flow velocity, and using a cooling agent with a lower temperature were more beneficial in improving the thermal performance of the metal hydride bed. In addition, thinning the hydride layer and enhancing the hydride material thermal conductivity were found to decrease the peak temperature. Furthermore, the heat transfer efficiencies of hydride materials, bed structures, and cooling systems should be well matched to obtain optimal operating parameters. The results highlighted the applicability of the proposed model and the coupled heat transfer method to effectively characterize the temperature patterns of uranium-based hydride beds during hydrogen absorption. [ABSTRACT FROM AUTHOR]

Aromatic reservation is one of the key evaluation index of textiles which be finished with fragrant micro‐/nanocapsules, and some researches discover that when the fragrant micro‐/nanocapsules penetrating into the spacing of textiles, the resulting aromatic textiles own much better carrying capability of micro‐/nanocapsules. Based on these phenomena, hence in our research, the matching up between pore sizes of cotton textile and sizes of fragrant micro‐/nanocapsules is investigated systematically in order to reveal the size effect on the durability of fragrant micro‐/nanocapsules in cotton textile. Firstly, the pore sizes of cotton textile are analyzed by three different techniques: 3D X‐ray microscopy (Micro‐CT), nitrogen adsorption/desorption method (BET), and mercury intrusion porosimetry (MIP) technique. Based on the pore sizes obtained from MIP technique, citronella oil/chitosan micro‐/nanocapsules with three corresponding sizes are prepared and then applied on cotton textiles through vacuum impregnation process. The pore sizes of cotton textile measured by MIP technique decrease from before finishing to after finishing with nanocapsules, which states that nanocapsules are entrapped inside the pores of cotton textile. Finally, the washing durability of aromatic cotton textile is evaluated by headspace–solid‐phase microextraction (HS‐SPME) technique combining with GC‐MS which can keep the fragrant micro‐/nanocapsules unbroken to simulate the "real" sniffing environment. The results show that aromatic cotton textile treated with nanocapsules possesses much better washing durability, which is met up with the results of pore size measurements: More nanocapsules are penetrating into the spacing of cotton textile fibers even the pores in fibers. [ABSTRACT FROM AUTHOR]

The safety and stability of metal hydride reactor (MHR) structure are significantly important for normal operations of hydrogen isotope storage and supply system. Moreover, considering that the experiments of studying the fatigue and creep properties of MHR structure are always time, money, difficulty and energy consuming. To further improve the service life of MHR as well as lower the failure risk, this paper proposes a system integration method based on ASME code validation, which combines genetic algorithm (GA) and back propagation neural network (BPNN) for rapid assessment of creep-fatigue life (CFL) and optimal design of structural parameters. First, numerical simulation is applied to perform thermal-mechanical coupled finite element analysis and verified by ASME code. Then, parametric sensitivity analysis and experimental design of parameter-based training set based on Taguchi method were performed, and response values are obtained from physical models combined with numerical simulations. Finally, a parametric optimization procedure combining BPNN and GA is developed based on the training data. In the workflow, parametric data flow is passed through the experimental design, numerical simulation, prediction and optimization processes. The results show that the proposed BPNN proxy model based on ASME code validation has good performance in predicting the life of MHR. Based on this, the life of the MHR is improved by 8% compared to the reference sample. • The correlation between creep-fatigue life (CFL) of metal hydride reactor (MHR) and design parameters is established. • Numerical models combining BPNN with ASME Code are available for assessment of CFL of MHR. • The sensitivity analysis is applied to measure the effect of design parameters on CFL of MHR. • Optimal design scheme of MHR is performed through an integrated design optimization method. [ABSTRACT FROM AUTHOR]

Background: Data-independent acquisition (DIA) is one of the most powerful and reproducible proteomic technologies for large-scale digital qualitative and quantitative research. The aim of this study was to use proteomic methodologies for the identification of biomarkers that are over or underexpressed in women with intrahepatic cholestasis of pregnancy (ICP) compared with controls and discover a potential biomarker panel for ICP detection. Methods: The participants included 11 ICP patients and 11 healthy pregnant women as controls. The clinical characteristic data and the laboratory biochemical data were collected at the time of recruitment. Then, a data-independent acquisition (DIA)-based proteomics approach was used to identify differentially expressed proteins (DEPs) in serum exosomes between ICP patients and controls. Finally, bioinformatics analysis was used to identify the relevant processes in which these DEPs were involved. Results: The proteomics results showed that there were 162 DEPs in serum exosomes between pregnant women with ICP and healthy pregnant women, of which 106 were upregulated and 56 were downregulated in ICP. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the identified proteins were functionally related to specific cell processes including apoptosis, lipid metabolism, immune response and cell proliferation, and metabolic disorders, suggesting that these may be primary causative factors in ICP pathogenesis. Meanwhile, complement and coagulation cascades may be closely related to the development of ICP. Receiver operating characteristic curve (ROC) analysis showed that the area under the curve values of Elongation factor 1-alpha 1, Beta-2-glycoprotein I, Zinc finger protein 238, CP protein and Ficolin-3 were all approximately 0.9, indicating the promising diagnostic value of these proteins. Conclusions: This preliminary work provides a better understanding of the proteomic alterations in the serum exosomes of pregnant women with ICP. [ABSTRACT FROM AUTHOR]

The objective of this work is to simulate the superelasticity and shape-memory effect in a single-crystalline nickel-titanium (NiTi) alloy through a molecular dynamics (MD) study. Cooling and heating processes for this material are reproduced to investigate the temperature-induced phase transformation in its microstructure. It is found that the martensitic transformation and its reverse process occur accompanied by an abrupt volume change, and the transformed variants lead to the appearance of the (001) type compound twin. In addition, the transform temperatures for martensite start (Ms) and austenite finish (Af) are determined, respectively. The results indicate that when the temperature is beyond Af during the compressive loading-unloading, the superelastic behavior becomes pronounced, which is attributed to the role of nanotwins on the transformation from the austenitic phase (B2) to martensitic phase (B19′). Compared to existing experimental data, a reasonable agreement is achieved through the modeling results, highlighting the importance of the compound twins for dominating the superelasticity of nanostructured NiTi alloys. [ABSTRACT FROM AUTHOR]

A common measure of deformation between atomic scale simulations and the continuum framework is provided and the strain tensors for multiscale simulations are defined in this paper. In order to compute the deformation gradient of any atom m, the weight function is proposed to eliminate the different contributions within the neighbor atoms which have different distances to atom m, and the weighted least squares error optimization model is established to seek the optimal coefficients of the weight function and the optimal local deformation gradient of each atom. The optimization model involves more than 9 parameters. To guarantee the reliability of subsequent parameters identification result and lighten the calculation workload of parameters identification, an overall analysis method of parameter sensitivity and an advanced genetic algorithm are also developed. [ABSTRACT FROM AUTHOR]

Owing to the limited literature on the impact performance of steel beams with hexagonal web opening (SBHWOs), this study conducted drop hammer tests and used finite element methods to investigate the dynamic response of SBHWOs subjected to impact loads. The impact force, displacements and accelerations of the beam, and the strains around a hexagonal web opening were collected during the tests. The impact process was captured by a high-speed camera. Furthermore, a finite element model was developed to analyze the post-impact internal forces of SBHWO, development and distribution of stresses in its web, the effect of impact position, and differences with solid webbed steel beam (SWSB). Results showed that the impact force, displacements, and web-post buckling of the SBHWO were significantly affected by impact energy, spacing between openings, and opening height. The average energy absorption ratio of the SBHWOs was found to be 51.56%. Additionally, the midspan acceleration decayed rapidly after impact and spread from the midspan towards the supports. The finite element analysis proved that numerical models can be used to accurately predict the dynamic responses of a SBHWO subjected to impact loads. The axial forces, shear forces, and bending moments of the SBHWO redistribute themselves during the impact, and the magnitude of the internal forces increased very rapidly before decaying gradually. The pattern through which stress developed in the SBHWO web was obtained using finite element modeling. A position close to the support approximately 1/4 of the calculated length of the SBHWO was the most unfavorable impact position. The SWSB was more resistant to impact load than the SBHWO. • The mechanical properties of steel beams with hexagonal web opening (SBHWOs) subjected to impact loads were studied by experiments and finite element method. • The impact force, displacements, and web-post buckling of the SBHWO were significantly affected by impact energy, spacing between openings, and opening height. • The average energy absorption ratio of the SBHWOs was found to be 51.56%. • The axial forces, shear forces, and bending moments of the SBHWO redistribute themselves during the impact. • A position close to the support approximately 1/4 of the calculated length of the SBHWO was the most unfavorable impact position. • The solid webbed steel beam (SWSB) was more resistant to impact load than the SBHWO. [ABSTRACT FROM AUTHOR]

This study explored the impact of irregular dynamic loads on castellated steel beams (CSBs) by conducting drop weight impact tests and establishing a numerical model using the nonlinear finite element method. The numerical simulation results were compared with the test results of the impact to verify its validity and analyze the buckling process and stress development of the CSB under impact load. Results showed that during the impact process, the maximum shear force was achieved first, followed by maximum bending moment and maximum deflection, respectively. It was observed that the increase in impact velocity and impact mass were unfavorable to the deflection of the CSBs, and resulted in an increase in the time required to dissipate impact energy. Furthermore, the ratio of spacing between openings to beam height exhibited a minor impact on the deflection in the range of 1.083–1.75. The ratio of opening height to beam height mainly affected the deflection near the midspan of the CSBs in the range of 0.5–0.7. The impact location significantly influenced the shape of the deflection curve. The larger the span-height ratio was, the more unfavorable it was for the CSBs to resist the impact. In addition, while the clamped support boundary condition reduced CSB deflection, it resulted in a rather substantial bending moment at the CSB ends. Based on the support rotation value as the damage evaluation index, a damage assessment curve with impact velocity and impact mass as the main control parameters was established. • The impact of irregular dynamic loads on castellated steel beams (CSBs) was explored by FE method. • The proposed numerical model could simulate the dynamic response of CSBs under the impact load. • A parameter analysis was determined the influential factors of the CSBs under impact load. [ABSTRACT FROM AUTHOR]

To investigate the impact resistance performance of web-opened steel beams (WOSBs) under impact loads, 26 specimens of WOSBs were designed and performed the falling-hammer impact tests, focusing on the impact energy, inter-opening space, opening height, and steel strength. The test results showed that the local deformations of WOSBs exhibited Vierendeel shear deformation and out-of-plane lateral buckling of the web under impact loads. At the initial impact stage, the time delay effect between the peak impact force and the peak reaction force accounts for approximately 9.77% of the total impact duration. The increase in impact energy and opening height had an adverse effect on the impact resistance performance of WOSBs. That is, as the impact energy (or opening height) increases, the average residual displacements for H1, H2, and H3 (H1, H2, and H3 represent WOSBs corresponding to three different steel materials: Q235, Q550, and Q690, respectively) increase by approximately 23.85% (18.07%), 34.05% (24.00%), and 33.20% (37.20%), respectively. The average impact efficiencies for H1, H2, and H3 are 77.38%, 72.90%, and 72.74%, respectively. This indicates that the unique geometric characteristics of WOSBs can be effectively utilized in the design of energy-absorbing structures. In conjunction with current steel structure design standards, a calculation method for the impact resistance performance of WOSBs was proposed by introducing the dynamic amplification factor and energy absorption ratio. • This study conducted falling-hammer tests to study the impact resistance performance and calculation method of web-opened steel beams (WOSBs) under impact loads. • Comparative examination of energy absorption characteristics of WOSBs under different influencing parameters. • The high-strength steel materials exhibited superior energy absorption and impact efficiency under impact loads, making them ideal energy-absorbing materials. • In conjunction with current steel structure design standards, a calculation method for the impact resistance performance of WOSBs was proposed by introducing the dynamic amplification factor and energy absorption ratio. [ABSTRACT FROM AUTHOR]

A stability-enhanced extraction gel membrane (EGM) with a thin functional layer of carrier for metal ion recovery was prepared and improved by cross-linking technology. Hydroxyl-terminated polybutadiene (HTPB) was used as the coupling agent to form a cross-linked network skeleton. Polymethylhydrosiloxane (PMHS) and HTPB were hydrosilylated to form a compact cross-linked structure. In addition, the D2EHPA (carrier) was fixed on polymer cross-linked structure. The prepared stability-enhanced EGM was characterized by SEM, EDS, ATR-IR, XPS. The influence of preparation parameters was studied and compared systematically. The optimum preparation conditions obtained from the data indicate that the total polymer concentration is 8 wt%, the mass ratio of HTPB/PMHS is 1:2, and the mass ratio of TEOS/VTES is 1:1. After 72 h of stability experiments, the mass transfer flux decreased from 2065.46 mg m−2 h−1–1718.82 mg m−2 h−1, the overall flux attenuation rate is only 16.8 %, which is 50.8 % lower than that of EGM without surface enhancing layer. In comparison, the flux attenuation rate of the traditional supported liquid membrane (SLM) even reached 100 % after 66 h. Therefore, the stability-enhanced EGM prepared in this study presents obviously higher operating stability compared with the EGMs operated at same conditions. The results suggest a potential approach for metal ions removal from water with high efficiency and stability. [Display omitted] • A novel method to improve the extraction gel membrane is proposed. • The mass transfer stability of the composite membrane is improved by locking the extractant through two cross-linking reactions. • The stability-enhanced extraction gel membrane improves the stability by one time on the premise of losing less flux. [ABSTRACT FROM AUTHOR]

Molecular dynamics (MD) simulations are carried out to comprehensively investigate the Hugoniot curve, isotherms, isentropes, and internal energy, as well as the Mie-Grüneisen equation of state (EOS) for single-crystal Al and Pb via multi-scale shock technology (MSST) in the open source software Large-scale Atomic/Molecular Massively Parallel Simulator, or LAMMPS. The temperatures (T H and T S) along the Hugoniot curve and isentrope, the entropy increment (ΔS H) along the Hugoniot curve, and the Grüneisen coefficient γ are calculated and discussed based on the linear relation of shock wave velocity and particle velocity. Meanwhile, based on the assumptions that γ is only a function of the specific volume V and the specific heat c V = constant, the typical incomplete Mie-Grüneisen EOS is thermodynamically extended to the complete equations of state (EOSs) utilizing the Hugoniot relation as the reference curve at pressures up to 300 GPa. The incomplete and complete Mie-Grüneisen EOSs show a concave surface in the pressure-specific volume-internal energy (P – V - E), pressure-specific volume-shock Hugoniot temperature (P – V - T H), and pressure-specific volume-entropy increment (P – V - ΔS H) spaces. • The linear relation of u s and u p provides a reliable basis for T H , T S , ΔS H , and γ. • The Born-Meyer potential predicts the Pc more exactly than the Morse potential. • The positive Δ S H of Al is greater than that of Pb, which is related to C 0 and V 0. • The incomplete Mie-Grüneisen EOS is extended to the thermodynamic complete EOSs. • Mie-Grüneisen EOSs show a concave surface in P – V - E , P – V - T H , and P – V - ΔS H spaces. [ABSTRACT FROM AUTHOR]

Highlights • The arc-dpa model is more accurate in comparison with NRT model when predicting N s. • Compared with T , E PKA is more likely to cause damages in Zr. • T has a significant influence on A , while has little effect on B in the power law. • PKA incident direction has little effect on N peak , t peak and N s except for t s. Abstract Atom-scale numerical calculations were performed to investigate the damage behavior in close-packed hexagonal zirconium (HCP-Zr) by primary irradiation through a molecular dynamics (MD) study. The influences of Primary Knock-on Atom (PKA) energy (E PKA), the PKA incident direction and the ambient temperature (T) on the cascade collision were studied comprehensively. The results show that the athermal recombination corrected displacements per atom (arc-dpa) model is more accurate in comparison with the Norgett-Robinson-Torrens (NRT) model when predicting the steady vacancy (N s). It was found that the vacancy peak (N peak), the peak time (t peak), and the steady time (t s) increase as E PKA and T increase. The steady vacancy also increases with the increase of E PKA. It was also found that N s increases and subsequently decreases by increasing T , suggesting that there is a suitable temperature to maximize N s when E PKA is constant. In addition, it was discovered that the PKA incident direction has little effect on vacancy dynamic history. It was proved that E PKA can worsen the irradiation damage in crystal Zr, but T can relieve such damage. In addition, the incident direction was found to have an insignificant effect on the damage. This study highlights that the steady vacancy concentration (C) can characterize the material irradiation damage. [ABSTRACT FROM AUTHOR]

Based on irreversible thermodynamic theory, a new constitutive model incorporating two internal variables was proposed to investigate the phase transformation and plasticity behavior in nickel-titanium (NiTi) shape memory alloys (SMAs), by taking into account four deformation stages, namely austenite elastic phase, phase transition, martensitic elastic phase, and plastic phase. The model using the material point method (MPM) was implemented by the FORTRAN code to investigate the stress wave and its propagation in a NiTi rod. The results showed that its wave propagation exhibited martensitic and austenitic elastic wave, phase transition wave, and plastic wave. However, a double-wave structure including the martensitic and austenitic elastic wave and plastic wave occurred when the martensitic elastic wave reached the phase transformation wave. Thus, the reflection wave at a fixed boundary exhibited a different behavior compared with the elastic one, which was attributed to the phase transition during the process of reflection. It was found that the stress increment was proportional to the velocity of phase transition wave after the stress wave reflection. In addition, the influences of loading direction and strain rate on the wave propagation were examined as well. It was found that the phase transition wave velocity increased as the strain rate increased. The elastic wave velocity of martensite under compressive conditions was larger than that under tensile loading. In contrast, the plastic wave velocity under compression was less than that subjected to the tensile load. [ABSTRACT FROM AUTHOR]

In this study, molecular dynamics (MD) simulations coupled with multi-scale shock technique (MSST) are used to predict the Hugoniot curve PH, Grüneisen coefficient γ and melting temperature Tm of single crystal (SC) and nanocrystalline (NC) aluminum (Al) with grain sizes of 6 and 60 nm at dynamic high pressure. The linear relation between the shock wave velocity and particle velocity is reproduced, and the results indicate that there is nearly no difference for the Hugoniot of SC and NC Al, which could be explained by the fact that the grain size effect on PH can be negligible at high pressure. Some empirical models are used to predict γ and Tm, which exhibit an opposite behavior. In addition, it is found that the melting pressure and temperature are 107.5 GPa, 3063 K for SC Al, while they are 109.5 GPa, 3082 K for NC Al, which have a reasonable agreement with the published work. [ABSTRACT FROM AUTHOR]

In this study, a simple approach to prepare quaternizated poly(vinyl chloride) (QPVC) ultrafiltration (UF) membrane was developed through soaking commercial PVC hollow fiber UF membrane in trimethylamine (TMA) solution. Infrared spectrum, 1 H nuclear magnetic spectrum and Thermogravimetric analysis showed that quaternary ammonium group was successfully grafted on the PVC membrane, X-ray photoelectron spectroscopy and zeta potential testing results pointed out that the amount of grafted quaternary ammonium group varied with reaction conditions. By the modification, the membranes changed gradually from negatively charged to positively charged, the hydrophilicity of PVC membrane was enhanced and the membrane pore shrinked, which resulted in the improvement of permeability and rejection simultaneously. Moreover, antibacterial research testified the PVC membrane was endowed antibacterial properties after modified of quaternization. [ABSTRACT FROM AUTHOR]

A novel and efficiently anchored 3-dimensional network extracting membrane (3D-NEM) with a thin functional surface layer comprising extraction carrier Bis(2-ethylhexyl) phosphate (D2EHPA) for nickel extraction was designed and studied in this paper. The active sites on the supporting Polytetrafluoroethylene (PTFE) hydrophilic ultrafiltration membrane were introduced by treating PTFE surface with potassium permanganate. Polydimethylsiloxane (PDMS) and Polymethylhydrosiloxane (PMHS) were applied to prepare a 3D network layer which is tightly anchored to the PTFE surface by introducing a crosslinking agent vinyltriethoxysilane (VTES). The prepared 3D-NEM was characterized by SEM, EDS, ATR-IR, XPS and etc. The influence of preparation parameters of 3D-NEM was studied and compared systematically. The optimum preparation conditions of 3D-NEM were based on a PDMS/PMHS/VTES ratio of 2:1:0.1 and a total polysiloxane concentration of 8 wt%. The operation stability test confirmed the average flux of the 3D-NEM in 72h reached 1871.16 mg·m-2·h-1, and only 14.42% flux declined at the end of operation. The proposed designed 3D network structure produced a 5.5 μm-functional extracting layer which has benefits in both effective fixing of D2EHPA and tight anchor to the supporting surface. This work has dual advantages in improving flux and reducing extractant loss compared to supported liquid membrane (SLM) and polymer inclusion membrane (PIM) processes. [Display omitted] • A 3-dimensional network extraction coating was synthesized, which can maintain transfer flux and stability. • The composition of 3D-NEM with optimal performance was determined by adjusting the amount of each component. • The mass transfer mechanism of nickel ions three-dimensional network composite membrane is fully analyzed. [ABSTRACT FROM AUTHOR]

• A matrix enhanced polymer inclusion membrane (ME-PIM) containing OHA and D2EHPA is prepared. • OHA was fixed in a polymer matrix and its synergistic effect with D2EHPA was used for the separation and recovery of Zn (Ⅱ). • The ME-PIM exhibits a high initial mass transfer flux of Zn (Ⅱ) of up to 4.73 μmol/(m2·s). Recovery of heavy metal ions from waste water has benefits both in terms of resources reuse and environmental protection. Polymer inclusion membrane (PIM) has received increasing attention as a gentle and simple method compared to other separation techniques for the removal and recovery of heavy metal ions. The extractant and matrix are the most important components of the PIM. In this paper, a novel matrix enhanced polymer inclusion membrane (ME-PIM) system containing both octyl hydroxamic acid (OHA) and di (2-ethylhexyl) phosphoric acid (D2EHPA) as the carriers as well as poly(vinyl) chloride (PVC) and poly (vinylidene fluoride- co -chlorotrifluoroethylene) (PVDF-CTFE) as the matrix was reported. The SEM results indicate that the PVC has excellent compatibility with OHA and D2EHPA, resulting in dense ME-PIM compared to PVDF-CTFE. The effects of OHA and D2EHPA with different carrier ratios on the transport and the stability of the membrane were examined using Zn (Ⅱ) as a representative of heavy metal ions. The optimal results of this work showed that the initial mass transfer flux value of Zn (Ⅱ) was as high as 4.73 μmol/(m2·s), corresponding to a permeability of 2.21 × 10−2 m/h, using the ME-PIM composed of 61 wt.% PVC and 22 wt.% OHA + 17 wt.% D2EHPA. All these results suggest that the ME-PIM has a much higher initial mass transfer flux than those of PIMs in literatures. The addition of OHA to PIM introduced extractive functional groups into the polymer chain, forming an efficient and progressive mass transfer path with the extractant D2EHPA. Utilizing two extractants with synergistic effects, this novel ME-PIM system provides a potential advantage in promoting the mass transfer of metal ions in a PIM. [ABSTRACT FROM AUTHOR]

Dopamine is a neurotransmitter, whose concentration change causes various nervous system disorders such as Parkinson’s disease. In this study, hydroxyethyl methacrylate-functionalized graphene oxide was prepared and used as the substrate for matrix-assisted laser desorption/ionization (MALDI) for the mass spectrometric determination of dopamine. The results show that hydroxyethyl methacrylate-functionalized graphene oxide materials may be used as a matrix for MALDI. This approach combines enrichment and detection in a single step. The new method greatly shortens the analysis time and significantly reduces the amount of sample required for the analysis. The detection limit of the method was 20 ng/mL. These features not only ensure that the method is suitable for trace analysis, but also extend the range of application of MALDI analysis to biochemical science. [ABSTRACT FROM AUTHOR]

[Display omitted] • Phase-field model was implemented in Abaqus via UEL and UMAT subroutines. • The geometric dependence of the burst hoop stress was studied. • Revealed competition induced by damage field merging and interference effects. • Critical distance between double cracks leaded to the minimal burst hoop stress. • The crack merging leaded to reduced burst hoop stress. The phase-field model was implemented in Abaqus via user-defined element (UEL) and user-defined material model (UMAT) subroutines for the brittle fracture analysis of a cladding tube. With this method, a scalar damage phase field was utilized to represent the diffuse crack topology, rather than numerical tracking of discontinuities in the cracking area. It was found that the burst hoop stress of the cladding was dependent on the competition of the interference effect and the damage field merging effect of double cracks. Moreover, there was a critical distance between the two cracks at which the burst hoop stress of the cladding reached a minimum. When the distance between two cracks was greater than the critical distance, the damage field merging effect was dominant, whereas when the distance was less than the critical distance, the interference effect was dominant. Furthermore, it was also observed that the burst hoop stress of the cladding was reduced due to the simultaneous initiation of two cracks. [ABSTRACT FROM AUTHOR]

Simple Summary: The brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), native to Asia, has been accidentally introduced to Europe and North America, where it has become a key pest by feeding on numerous important crops. Although H. halys has not yet established in Australia, there is a general consensus that this is only a matter of time, and thus, it is prudent to investigate management options. Previous studies have modelled the potential distribution of H. halys and one of its principal natural enemies, Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae). Here, we developed a similar model of the potential distribution of Trissolcus mitsukurii (Ashmead), which is a primary parasitoid of H. halys in Japan, and which was introduced to Australia in the 1960s to control another introduced pest. We used the three models to examine the overlap in the projected distributions of both T. mitsukurii and T. japonicus with H. halys, and to assess the potential for the two Trissolcus species to help mitigate the impacts of H. halys in its global adventive range. The brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is native to northeast Asia. It was accidentally introduced to Europe and North America, where it has become a key pest, feeding on many important crops. Previous eco-climatic niche modelling indicates that H. halys could expand its distribution vastly, and numerous border interceptions of this pest in many countries, including Australia and New Zealand, indicate that it would be prudent to prepare for its eventual arrival. Similar niche modelling was used to assess the potential distribution of Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae), the key parasitoid of H. halys in China. Trissolcus mitsukurii (Ashmead) is one of the main parasitoids of H. halys in Japan. It is known to have existed in Australia since the early 20th century and was also specifically introduced to Australia in the 1960s, and it has now also invaded Italy. We used CLIMEX to model the climatic niche of T. mitsukurii to estimate its global potential distribution. We found that T. mitsukurii should be able to significantly expand its range globally, and that there is a significant degree of overlap in the projected ranges of T. mitsukurii, T. japonicus and H. halys. From a biological control perspective, this implies that the two Trissolcus species may be able to help mitigate the potential impacts of H. halys. [ABSTRACT FROM AUTHOR]

• Building a new numerical model to simulate the subsonic tritium leakage and diffusion. • Developing interface codes of quantitative relations between mass flow rate and time. • The differences of tritium diffusion behavior in open and closed space are revealed. • Effects of leak apertures and ambient wind on tritium diffusion are investigated. Based on the knowledge that the surroundings of tritium leakage and diffusion in hydrogen storage vessels can be either open space or closed space, the subsonic jet flow of a slow tritium leak from a hydrogen storage bed under open and closed spatial conditions is simulated by Fluent finite element software. Furthermore, the quantitative relationship between mass flow rate and time is established by using the user defined function (UDF) to compile interface codes. The subsonic tritium jet, velocity profiles, tritium diffusion distance, and the tritium concentration along the jet trajectory are obtained in two different scenarios (open space and closed space). The results show that the closed space inhibits the vertical convection diffusion of tritium and has a favorable improving effect on the horizontal convection diffusion of tritium, whereas the open space has the opposite influence on the convection diffusion of tritium. In addition, an eddy current whirlpool develops under the closed space condition. The concentration distribution along the jet center line can be significantly influenced by the spatial boundary condition and leak aperture. An increase of leak aperture facilitates vertical diffusion of tritium and the velocity near the leakage hole. The oblique downward wind and horizontal wind lead to an enhancement of tritium cloud horizontal drifting. The oblique upward wind can be considered as a method to effectively dilute leaked tritium concentration. [ABSTRACT FROM AUTHOR]