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[Display omitted] • Aminomalononitrile (AMN) was used to enhance Mg2+/Li+ separation of PEI-TMC membrane. • The interaction of AMN with Mg2+/Li+ ions and H 2 O were explored by Density Functional Theory. • Small-molecule embedded mechanism of permeance enhancement for nanofiltration membrane was proposed. In addressing lithium supply shortages driven by increased energy demand, nanofiltration membrane technology is crucial for recovering lithium from salt lake brines. Overcoming the challenge of achieving high selectivity for Li+ and water permeability in polymer nanofiltration membranes, this study proposes a simple approach using Aminomalononitrile (AMN) intercalation to modify polyamide layers. Density functional theory simulations predict AMN's superior selectivity and enhanced hydrophilicity. Stable intercalation of AMN between polyethyleneimine (PEI) molecules is demonstrated, synergistically enhancing water permeability and Li+ selectivity. The resulting PEI/AMN-TMC membrane exhibits exceptional Li+ selectivity and improved water permeability (13.1 L·m−2·h−1·bar−1), 2.9 times higher than traditional PEI-TMC membranes. Stable performance for over seven days, along with anti-scaling and anti-bacterial properties, underscores its practicality. This investigation sheds light on membrane structure regulation through small-molecule intercalation, offering insights into precise adjustments for enhanced water permeability and ion selectivity. [ABSTRACT FROM AUTHOR]

Abstract The effect of Y 2 O 3 on the glass transition kinetics, crystallization kinetics, phase separation and crystallization behavior of 60ZnO–30B 2 O 3 –10SiO 2 glass has been investigated by non-isothermal differential thermal analysis, scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). The glass transition activation energies E g calculated by using both Kissinger and Moynihan model decrease from 668 kJ/mol to 573 kJ/mol for Kissinger model, and 682 kJ/mol to 587 kJ/mol for Moynihan model with the increase of yttrium oxide doping content from 0 to 6 mol%. And the glass crystallization kinetics parameters, crystallization activation energy E c and Avrami exponent n stands for crystal growth, are also obtained on the basis of several well developed equations. Increase of about 58 kJ/mol in Ec values obtained by different theoretical equations is caused by addition of 6 mol% yttrium oxide into 60ZnO–30B 2 O 3 –10SiO 2 glass, and the Avrami exponent (n close to 2) suggests that crystal growth in 60ZnO–30B 2 O 3 –10SiO 2 glass doped with or without yttrium is mainly one-dimensional growth of crystals. The results on the phase separation and crystallization behavior occurred at 893 K and 993 K respectively for base and doped glass, are well consistent with the glass transition and crystallization kinetics results. Hence, addition of yttrium oxide into 60ZnO–30B 2 O 3 –10SiO 2 glass decrease the glass transition activation energy while increase the crystallization activation energy of glass, thereby the stability of glass structure is improved. Phase separation phenomenon and crystallization behavior occurred at glass surface provide some useful information for preparing glass ceramics with micro- or nano-crystals in surface. [ABSTRACT FROM AUTHOR]

Energy recovery device (ERD) is a critical power component in seawater reverse osmosis (SWRO) desalination system. In this study, the energy transfer and flow characteristics for an innovative integrated energy recovery and pressure boost device (IERPBD) are investigated. The IERPBD which consists of a rotary pressure exchanger (RPE) and an axial piston type booster pump (APBP) is introduced in Section 2. To optimize both the structure parameters and working conditions of IERPBD, a series of three-dimensional (3D) CFD simulations are carried out. The CFD simulations for the RPE with port plate silencing grooves are conducted with a set of operating conditions through orthogonal designed theory. It should be noted that the leakage through the lubricating gaps of valveport plate, fluid compressibility effect and cavitation damage are considered in the simulation. And partial numerical results are validated by comparison with the results from other research groups. The mixing process, pressure distribution, components distribution, leakage flow characteristics and related characteristic parameters of RPE are presented in Section 3. And then the optimal parameters of RPE with a duct diameter of 10 mm, duct length of 70 mm, 12 ducts with fresh seawater flow of 10.8 L/ min were used to design the IERPBD. The energy transfer and flow characteristics of IERPBD were also presented with different gap heights of the valve-port plate interface. The simulation results turned out that when the lubricating gap height of valve-port plate changes from 5 μm to 20 μm, the flow ripple rate of RPE could increase from 6.15% to 36.13%, whereas the energy recovery efficiency of RPE could decrease from 97.2% to 49.8%. Therefore, a well-designed lubricating gap of valve-port plate could improve both energy transfer and flow characteristics of IERPBD. This research will lay the foundation for the further development of high efficiency and low fluid noise IERPBD. [ABSTRACT FROM AUTHOR]

SO 2 and NO from coal combustion are the main precursors of acid rain, regional haze, and photochemical smog. Advanced oxidation strategies can be used to simultaneously remove SO 2 and NO from flue gas under a low temperature. Two metal-organic frameworks (MOFs), FeBDC and CuFeBDC, were synthesized and used to activate peroxymonosulfate (PMS) for the oxidation and absorption of flue pollutants. The characterization results revealed that MOFs contained the redox pairs Fe(II)/Cu(I) and Fe(III)/Cu(II). Fe(II)/Cu(I) initiated firstly the PMS activation. Then, the Fe(II-III-II) and Cu(I-II-I) redox cycles continuously activated PMS and generated reactive species. MOFs-PMS removed 76.6 % and 86.5 % of NO in the presence of FeBDC and CuFeBDC catalysts, respectively. 100 % of SO 2 was removed. CuFeBDC exhibited the efficient catalytic properties for the removal of NO and SO 2 in PMS solution, and could be recycled and regenerated. After five cycles, the removal efficiencies of NO and SO 2 were 71.2 % and 100 %, respectively, and NO and SO 2 emissions in the outlet were lower than the emission limit when using CuFeBDC-PMS. During the oxidation and absorption process, NO and SO 2 were first oxidized to NO 2 - and SO 3 2- as intermediates, then formed the final products of NO 3 - and SO 4 2-. Radical scavenging experiments and electron paramagnetic resonance measurements revealed that both radical (SO 4 -•, •OH) and non-radical pathways (1O 2) contributed to the efficient oxidation of NO/ SO 2. 1O 2 was the predominant reactive oxygen species for the removal of NO, while SO 4 -• and •OH were responsible for the removal of SO 2. [Display omitted] • Two MOFs, FeBDC and CuFeBDC, were synthesized through a facile hydrothermal route. • MOFs contained the redox pairs Fe(II)/Cu(I) and Fe(III)/Cu(II). • 86.5 % of NO and 100 % of SO 2 are removed in the presence of CuFeBDC catalysts. • The intermediates were NO 2 - and SO 3 2- and the final products were NO 3 - and SO 4 2-. • 1O 2 dominated NO removal, while SO 4 -• and •OH played a dominant role in SO 2 removal. [ABSTRACT FROM AUTHOR]

A series of reactive pour point depressants (PPD) with anhydride group were prepared, and their action mechanism had been investigated by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC) and cross-polarized light microscope. The results showed that the prepared pour point depressants had obvious pour point depressing effect on crude oil. Its action mechanism was concluded that PPD could react with the resin and asphaltene in the crude oil to generate a new macromolecule when crude oil was treated with PPD-3 at 90 °C. The new macromolecule further formed a new agglomerate structure by association with the asphaltene and resin in crude oil, which worked as a new nucleator to provide nucleation sites for wax crystal instead of the original asphaltene–resin agglomerate structure, and then improved the flowability of crude oil. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes experimental investigations of an adaptive control for suppressing thermo-acoustic instabilities in Rijke tube. Strong coupling between pressure oscillations and unsteady heat release excites a self-sustained acoustic wave which results in a loud, annoyed sound and may also lead to a structural damage to the combustion chamber. Adaptive controller based on dynamic compensation is adopted to suppress the instabilities in Rijke tube. The controller provides proper control action in response to pressure changes in combustors. Unknown noise and disturbance will be estimated and compensated actively by adaptive controller, which makes the feedback control less dependent on the precise model of the complex thermo-acoustic processes in Rijke tube. Experiment results confirm the controller employed is effective in breaking up the oscillations in Rijke tube. [Copyright &y& Elsevier]

Abstract: The cotton fabric was chemically modified with the acrylamide through Michael addition reaction and Hoffman degradation reaction. And the optimum chemical modification conditions were determined. The molecular structure of the modified cotton fabric was identified by Fourier transform infrared spectroscopy (FTIR). The structures of both the raw and modified cotton fabrics were investigated by X-ray diffraction and scanning electronic microscopy. The raw and modified cotton fabrics were dyed using commercial reactive dyes with vinyl-sulfone groups. The results showed that the total dye utilization of modified cotton fabrics in the salt-free dyeing was higher than that of raw cotton fabrics in the conventional dyeing. And the color fastness properties and tear strength of modified fabrics were both satisfactory. [Copyright &y& Elsevier]

Abstract: Influence of lanthanum stearate (LaSt3) as a co-stabilizer on stabilization efficiency of calcium stearate (Ca)/zinc glutarate (Zn) stabilizers to polyvinyl chloride (PVC) at 180 °C in air was investigated. The results showed that combination of LaSt3 with Ca/Zn stabilizers presented an obvious improvement of stabilization efficiency to PVC compared with the Ca/Zn stabilizers. Moreover, addition of LaSt3 to the Ca/Zn stabilizers could significantly enhance static stability time of PVC. Incorporation of 2 phr LaSt3 co-stabilizer to PVC containing 3 phr Ca/Zn stabilizers resulted in marked increase of onset degradation temperature and reductions in average degradation rate as well as the dynamic storage modulus (G′) and loss modulus (G″) at 180 °C. Influence of Ca/Zn ratio on tensile strength of PVC in the absence or in the presence of LaSt3 was discussed in detail. At low Ca/Zn ratios LaSt3 had an obvious improvement in the tensile strength, while at high Ca/Zn ratios this effect became inconspicuous. [Copyright &y& Elsevier]

Abstract: When female mice are mated, they form a memory to the pheromonal signal of their male partner. Several lines of evidence indicate that the neural changes underlying this memory occur in the accessory olfactory bulb (AOB) at the first stage of the vomeronasal system. The formation of this memory depends on the mating-induced release of noradrenaline in the AOB. In addition to noradrenaline, the neuropeptide oxytocin (OT) is also released within the central nervous system during mating. Because OT has been implicated in social memory and its receptors are expressed in the AOB, we hypothesized that OT might promote the strength of synaptic transmission from mitral to granule cells in the AOB. To test this hypothesis, we analyzed the lateral olfactory tract-evoked field potential that represents the granule cell response to mitral cell activation and its plasticity in parasagittal slices of the AOB. Of the 10-, 20-, 50-, and 100-Hz stimulations tested, the 100-Hz stimulation was optimal for inducing long-term potentiation (LTP). OT paired with 100-Hz stimulation that only produced short-term potentiation enhanced LTP induction in a dose-dependent manner. OT-paired LTP was blocked by both the selective OT antagonist desGly-NH2,d(CH2)5[Tyr(Me)2,Thr4]-ornithine vasotocin and the N-methyl-d-aspartate (NMDA) receptor antagonist dl-2-amino-5-phosphonovaleric acid. These results indicate that OT can function as a gate to modulate the establishment of NMDA receptor-dependent LTP at the mitral-to-granule cell synapse in the AOB. [Copyright &y& Elsevier]

Abstract: Corrosion is one of the most damaging mechanisms in many engineering materials and structures. A computational model that simulates the multi-pit corrosion damage initiation and growth in aircraft aluminum is developed. The computational model based on cellular automata approach uses the local rules governing the electrochemical reactions, and simulates them as a discrete dynamical system. The results of corrosion damage initiation and growth obtained from simulation are compared qualitatively as well as quantitatively to the experimental data obtained on engineered corrosion specimens from Raytheon Systems Company, Texas. The effect of various electrochemical parameters on the multi-pit corrosion initiation and growth obtained from the simulation are presented and discussed. The results presented illustrate the feasibility of the new cellular automata approach to model multi-pit corrosion damage initiation and growth in aircraft aluminum materials. [Copyright &y& Elsevier]

Objective To isolate the bioflocculant-producing bacteria from activated sludge and investigate the flocculating characteristics of the newly isolated bioflocculant. Methods Bacteria were screened from activated sludge samples to isolate bioflocculant-producing bacteria. Flocculating activity was used as a measure of the flocculating capability of the bioflocculant. Results A novel bioflocculant-producing bacterium was isolated, which was identified to belong to genus Aeromonas and named as Aeromonas sp. N11. Flocculating activity increased in the presence of K+, Na+, or Ca2+. The highest flocculating activities for kaolin suspension were obtained in acidic pH ranges, and optimum pHs for it were 3.0, 4.0, and 5.0 with 1 mmol/L K+, Ca+, and Na+ present, respectively. The highest flocculating activities for soil suspension were observed at pH 8.0. The bioflocculant had a good flocculating activity and could achieve a flocculating activity of 92.4% for kaolin suspension at a dosage of only 1 mg·L-1, and its activity in kaolin suspension was decreased by only 9.2% after heating at 100°C for 60 min. Conclusion The bioflocculant produced by Aeromonas sp. N11 has strong flocculating activity and high stability, which affords high possibility of its practical use. [ABSTRACT FROM AUTHOR]

In this paper, a partition method is proposed to study the high voltage devices with the step doping profile for the first time. It has been proposed that its breakdown voltage can be approached to that of the linearly graded devices with similar forward voltage drop (Vce). In addition, by this method, the breakdown voltage can be deduced and its corresponding issue location is also fingered out in the step drift region. Furthermore, in order to reduce the undesirable additional masks, the degraded factor (D) is developed to obtain better performance with the least number of frames. Eventually, a 660 V step analytical results are compared with a 606.6 V MEDICI simulation and this shows that the partition method is very effective. [Copyright &y& Elsevier]

Inhalable particle pollutants from industrial processes have a typical size of less than 2.5μm and have recently gained much attention because they are considered as a serious public health concern. These particles can penetrate deeply into the lungs and are difficult to remove by conventional separation devices. A turbulent gas jet was introduced into the acoustic agglomeration chamber to form the coupling external field. This work studied the effect of operation parameters on the agglomeration behavior of inhalable particles, such as frequency (280–3500Hz), sound pressure level (100–130dB), jet velocity (14–28m/s) and injection angles (40–140°). Scanning electron micrographs of aerosols, with and without external fields, demonstrated that the inhalable particles were removed by the formation of large aggregates. The mass median diameter of the particles increased from 2.47μm to 6.48μm after exposure to the coupling external fields, i.e. sound frequency 1416Hz, sound pressure level 128dB, jet velocity 25.5m/s and injection angle 90°. The inhalable particles had maximum agglomeration efficiency at 1416Hz at an SPL of 128dB. Increasing the sound pressure level from 100dB to 128dB improved the removal efficiency. High gas velocity of 28.3m/s favors the collision of inhalable particles in a turbulent flow. However, increasing gas velocity initially enhanced and subsequently decreased the removal efficiency in the coupling external field. The maximum efficiency occurred at 22.5m/s jet velocity. Vertically injected turbulent gas jet was the best method to improve removal efficiency. The application of an external field resulted in higher removal efficiency for particles smaller than 1μm and larger than 5μm, but relative lower removal value for mid-sized particles (1–5μm). [ABSTRACT FROM AUTHOR]

Abstract Aims WHO grade I meningiomas include several subtypes that differ in terms of surgical planning and prognosis. We aim to analyze the relationship between magnetic resonance imaging (MRI) features and pathological parameters for each WHO grade I meningioma subtype to improve diagnostic value. Materials and methods Patients with WHO grade I meningiomas underwent pathology pathological examination and surgery at our hospital. MRI findings included signal intensity on T1WI and T2WI and, the enhancement degree in contrast-enhanced, and the degree of peritumoral edema in patients were reviewed. 1H-MRS was performed for the different meningioma subtypes. The correlation between MRI features and pathology was determined using a Kruskal-Wallis H test (P < 0.05). Key findings Angiomatous meningiomas mainly showed a low T1WI signal, a high T2WI signal, a high occurrence rate of peritumoral edema, mainly with moderate or severe peritumoral edema, and homogeneous enhancement. Meningothelial meningiomas mainly showed T1WI and T2WI iso-intense signals, mainly moderate or severe peritumoral edema, and moderate enhancement. Mixed, fibroblastic, and psammomatous meningiomas showed mixed signals, much overlap of the T1WI and T2WI signals, mainly mild or moderate peritumoral edema, and mild or moderate enhancement that could be inhomogeneous. A significant difference was noted in apparent diffusion coefficient (ADC) values and in some 1H-MRS indicators among different meningioma subtypes. Significance Angiomatous meningiomas were the most easily identified subtype, followed by meningothelial meningiomas. No obvious difference was observed among the mixed, fibroblastic, and psammomatous meningiomas, but differences were observed between angiomatous and meningothelial meningiomas. [ABSTRACT FROM AUTHOR]

Jasmonates (JAs) play important roles in gummosis in peach. Mechanical damage, methyl jasmonate (MeJa), and ethylene can induce gummosis on peach shoots in the field. In this study, we used MeJa (2%, w/w) to induce gummosis on current-year shoots in peach on high temperature (35 °C). Based on the experimental model, we studied the influence of factors on the development of peach gummosis. Our experimental results showed that high temperature could promote gummosis development induced by MeJa. Exogenous CaCl 2 treatment reduced the degree of gummosis by increasing the calcium content in shoots, which is conducive to the synthesis and maintenance of the cell wall. Using digital gene expression (DGE), 3831 differentially expressed genes were identified in the MeJa treatment versus the control. By analyzing changes in gene expression associated with cell wall degradation, genes encoding pectin methylesterase (PME) and endo-polygalacturonase (PG) were found to be significantly induced, suggesting that they are key enzymes in cell wall degradation that occurs during MeJa-induced gummosis. Genes for glycosyltransferase (GT) and cellulose synthase (CS) were also significantly upregulated by MeJa. This result suggests that MeJa treatment not only promotes the degradation of polysaccharides to destroy the cell wall, but also promotes the synthesis of new polysaccharides. We also analyzed changes in gene expression associated with sugar metabolism, senescence, and defense. MeJa treatment affected the expression of genes related to sugar metabolism and promoted plant senescence. Among the defense genes, the expression pattern of phenylalanine ammonium lyase (PAL) suggested that PAL may play an important role in protecting against the effects of MeJa treatment. Our experimental results showed that MeJa treatment can promote the biosynthesis and signal transduction of ethylene in peach shoots; they can induce gummosis on peach shoots respectively, and there are overlaps between the molecular mechanisms of gummosis induced by them, the intersection point between them remains unclear. [ABSTRACT FROM AUTHOR]

Given the depletion of shallow water wind energy resources and maturity of Floating Offshore Wind Turbine (FOWT), offshore wind technology is shifting from bottom fixed to floating. As a consequence, the research has concentrated on the points such as energy production and cost, which affect the commercialization of the wind farm. Researchers have studied the individual factors affecting these points, and used over-simplified methods. In order to provide a systematic and high quality analysis, we conducted a comprehensive study of wind farm based on unsteady Reynolds Average Navier–Stokes simulations two FOWTs and detailed decomposition of cost components. Specifically, under different scenarios, we compare the two FOWT performances, such as the power output, torque and six degrees of freedom motion response. The influences of the relative rotating direction and relative positions are analyzed. More importantly, we extensively discuss the impact of the interaction on the FOWT levelized cost of energy under various scenarios. It is found that tandem layout with a distance of 9. 25 D is the practical optimal parameter choice. This study is expected to provide guidances and insights for offshore wind researchers and governmental decision makers in future wind farm plannings. • Develop an integrated approach to estimate the floating wind LCOE. • Give a systematic analysis of two floating wind turbines. • Provide the optimal distance between turbines in the wind farm. • Show the effects of wave induced motion. [ABSTRACT FROM AUTHOR]

In this paper, a highly selective sample clean-up procedure combining magnetic dummy molecular imprinting with solid-phase extraction was developed for rapid separation and determination of 4-nonylphenol (NP) in the environmental water samples. The magnetic dummy molecularly imprinted polymers (mag-DMIPs) based on multi-walled carbon nanotubes were successfully synthesized with a surface molecular imprinting technique using 4-tert-octylphenol as the dummy template and tetraethylorthosilicate as the cross-linker. The maximum adsorption capacity of the mag-DMIPs for NP was 52.4 mg g-1 and it took about 20 min to achieve the adsorption equilibrium. The mag-DMIPs exhibited the specific selective adsorption toward NP. Coupled with high performance liquid chromatography analysis, the mag-DMIPs were used to extract solid-phase and detect NP in real water samples successfully with the recoveries of 88.6-98.1%. [ABSTRACT FROM AUTHOR]

Coal combustion often produces mercury emissions. Coal gasification fine slag (FS) was used to remove Hg0 from flue gas. To increase the removal efficiency, two ionic liquids (IL-T and IL-B) were immobilized on the surface of FS. The mercury removal performance was evaluated in a fixed-bed reactor in the presence of SO 2 + O 2. The experimental results showed that the mercury removal efficiency increased when the adsorbents were supported by ionic liquids (FS-T and FS-B). The effect of 0.6% SO 2 on the capture of Hg0 was negligible for all three adsorbents. The total mercury removal efficiencies exceeded 90% for FS-T and FS-B in the atmosphere of 0.6% SO 2 + 6% O 2. When the initial mercury concentration was 60 μg/m3, the effective adsorption time was about 80 min for FS and longer than 120 min for FS-T and FS-B. In the presence of 0.6% SO 2 + 6% O 2 , Hg0 and Hg2+ were detected in exhaust gas using FS and FS-B and in solid phase using the three adsorbents. According to XPS analysis, an oxidation reaction occurred on the surface of FS and FS-T. For FS-B, the Br− anion of IL-B was the active site and oxidized Hg0 to Hg2+ on the surface as well as in the gas phase. • 0.6% SO 2 was not affected the capture of Hg0. • The mercury removal exceeded 90% for FS-T and FS-B in 0.6% SO 2 + 6% O 2. • A low concentration of SO 2 promoted the oxidation of Hg0 to Hg2+. • Oxidation reaction occurred on the surface of the adsorbents of FS and FS-T. • Oxidation process happened both the surface and gas phase. [ABSTRACT FROM AUTHOR]