Inversion Technique Research Articles

Performance Improvement Polyvinylidene Fluoride (PVDF) Mordenite Membranes for Oil-in-Water Emulsion Separation

Improving the performance of membranes appropriate for oil-in-water separation is a global challenge. In this study, we prepared a PVDF/Mordenite (PZM) membrane and determined its properties to separate oil-in-water emulsions to address this challenge. The PVDF and PZM membranes were fabricated using the phase inversion technique and applied to separate two types of oil-in-water emulsions 1:99 (wt%), including vegetable oil and used cooking oil emulsion. PVDF polymer with DMAc solvent was added to mordenite with a concentration variation of mordenite. The addition of mordenite did not affect the increase of the β fraction on the hybrid membrane surface but could improve the membrane hydrophilicity. The addition of mordenite in the PVDF membrane has improved the characteristics of the membrane, including water flux, rejection membrane >90%, and FRR up to two times greater than a pristine PVDF membrane. Morphological analysis of the membrane confirmed an asymmetric membrane composed of finger-like and sponge-like. Combining mordenite and PVDF membrane to separate oil-in-water emulsions provides a new approach to oil wastewater treatment.

Type 2 diabetes mellitus has a positive role in osteomyelitis: A Mendelian randomization analysis.

According to clinical evidence, type 2 diabetes mellitus (T2D) and osteomyelitis (OM) are currently the 2 major causes of mortality and morbidity in humans. Despite accounts of their coexistence, there is still no understanding of their fundamental connection. We attempted to assess the causal effect of T2D on OM using the two-sample Mendelian randomization method. The whole gene-wide association study's aggregate data were examined. Single-nucleotide polymorphisms, which have a substantial correlation with T2D, were used as instrumental variables in a two-sample Mendelian randomization (MR) analysis to assess the causal relationship between T2D and OM risk using the inverse variance weighting, MR-egger regression, and weighted median approaches, respectively. A total of 114 single-nucleotide polymorphism were used as instrumental variables in this analysis. The inverse variance-weighted analysis showed a significant causal relationship between T2D and OM, indicating that T2D has a detrimental effect on OM risk. The odds ratio for the causal effect of T2D on OM was 1.317, with a 95% confidence interval of (1.140, 1.522) (P < .001). To assess heterogeneity, Cochran Q test statistics and MR-Egger regression were applied in the inverse variance-weighted technique. The P-value of .737 indicated a considerable level of heterogeneity was not absent in the data. This study used Mendelian randomization analysis to establish a causal relationship between T2D and OM. The findings suggest that T2D may increase the risk of OM.

Modified hepatic left lateral lobe inversion in laparoscopic proximal gastrectomy: An analysis of 13 cases.

In laparoscopic proximal gastrectomy (LPG), the prolapse of the hepatic left lateral lobe near the lesser curvature and esophageal hiatus can obstruct the field of vision and operation. Therefore, it is necessary to retract or obstruct the hepatic left lateral lobe to ensure a clear field of vision. To investigate the safety and clinical efficacy of the modified hepatic left lateral lobe inversion technique for LPG. A retrospective analysis was conducted on the clinical data of 13 consecutive patients with early-stage upper gastric adenocarcinoma or adenocarcinoma of the esophagogastric junction treated with LPG from January to December 2023 at the Department of Gastrointestinal Surgery, Second Affiliated Hospital of Fujian Medical University. The modified hepatic left lateral lobe inversion technique was used to expose the surgical field in all patients, and short-term outcomes were observed. In all 13 patients, the modified hepatic left lateral lobe inversion technique was successful during surgery without the need for re-retraction or alteration of the liver traction method. There were no instances of esophageal hiatus occlusion, eliminating the need for forceps to assist in exposure. There was no occurrence of intraoperative hepatic hemorrhage, hepatic vein injury, or hepatic congestion. No postoperative digestive complications of Clavien-Dindo grade ≥ II occurred within 30 days after surgery, except for a single case of pulmonary infection. Some patients experienced increases in alanine aminotransferase and aspartate aminotransferase levels on the first day after surgery, which significantly decreased by the third day and returned to normal by the seventh day after surgery. The modified hepatic left lateral lobe inversion technique has demonstrated satisfactory results, offering advantages in terms of facilitating surgical procedures, reducing surgical trauma, and protecting the liver.

Manufacture and performance assessment of PVDF-La@TiO2 Photocatalyst implanted membrane for efficient produced water treatment via ozonation-adsorption process under visible-light exposure

This research aims to develop a visible light-activated photocatalytic membranes for produced water treatment system by employing the phase inversion technique for implantation of La@TiO2 photocatalytic nanoparticles into PVDF membrane at concentrations varying from 0 % to 2 % wt. The results demonstrated significant amplification of COD and NH3-N removal efficiency. Implantation of the photocatalyst into PVDF membranes via bulk mixing, coupled with elemental doping and combination with La@TiO2 appreciably reduces band gap energy and increases visible light absorption thereby improves membrane's optical properties. SEM-EDX analysis confirms uniform distribution of La@TiO2 nanoparticles on the membrane surface, which leads to amplify membrane's hydrophilicity and water absorption. The modified membrane facilitated concurrent photocatalytic degradation and filtration processes that lead to remarkable reductions in TDS, COD, and NH3-N pollutants, with the highest flux was achieved when 1.5 % wt. La@TiO2 was incorporated into the membrane matrix. Obviously, adsorption and ozonation processes promote synergistic effect and amplify pollutant flux and efficiency to a greater extent. Furthermore, the modified membrane exhibited extraordinary antifouling properties and stability, providing excellent reusability with a 96.22 % fouling reduction rate after five consecutive cycle tests.

Mobility Gaps of Hydrogenated Amorphous Silicon Related to Hydrogen Concentration and Its Influence on Electrical Performance.

This paper presents a comprehensive study of hydrogenated amorphous silicon (a-Si)-based detectors, utilizing electrical characterization, Raman spectroscopy, photoemission, and inverse photoemission techniques. The unique properties of a-Si have sparked interest in its application for radiation detection in both physics and medicine. Although amorphous silicon (a-Si) is inherently a highly defective material, hydrogenation significantly reduces defect density, enabling its use in radiation detector devices. Spectroscopic measurements provide insights into the intricate relationship between the structure and electronic properties of a-Si, enhancing our understanding of how specific configurations, such as the choice of substrate, can markedly influence detector performance. In this study, we compare the performance of a-Si detectors deposited on two different substrates: crystalline silicon (c-Si) and flexible Kapton. Our findings suggest that detectors deposited on Kapton exhibit reduced sensitivity, despite having comparable noise and leakage current levels to those on crystalline silicon. We hypothesize that this discrepancy may be attributed to the substrate material, differences in film morphology, and/or the alignment of energy levels. Further measurements are planned to substantiate these hypotheses.

Hydrogen susceptibility of Al 5083 under ultra-high strain rate ballistic loading

Abstract The effect of hydrogen on the ballistic performance of aluminum (Al) 5083H131 was examined both experimentally and numerically in this study. Ballistics tests were conducted at a 30° obliquity in accordance with the ballistic test standard MIL-DTL-46027 K. The strike velocities of projectiles were ranged from 240 m s−1 to 500 m s−1 level in the room temperature. Electrochemical hydrogen charging method was utilized to introduce hydrogen into material. Chemical composition of material was analyzed using energy dispersive X-ray (EDX) analysis. Instant camera pictures were captured using high-speed camera to compare H-uncharged and H-charged specimen ballistics tests. The volume loss in partially penetrated specimens were assessed using the 3D laser scanning method. Microstructural examinations were conducted utilizing scanning electron microscopy (SEM). It was observed that with the increased deformation rate, the dominance of the HEDE mechanism over HELP became evident. Furthermore, the experimental findings were corroborated through numerical methods employing finite element analysis (FEM) along with the Johnson–Cook plasticity model and failure criteria. Inverse optimization technique was employed to implement and fine-tune the Johnson–Cook parameters for H-charged conditions. Upon comparing the experimental and numerical outcomes, a high degree of consistency was observed, indicating the effective performance of the model.

A Pn-wave spectral inversion technique based on trust region reflective algorithm

This paper suggests utilizing the trust region reflective (TRR) algorithm to address the inverse problem related to seismic spectrum analysis of Pn waves. By applying this approach, it becomes feasible to simultaneously deduce the seismic moment, corner frequency, tomographic model of Pn-wave attenuation, and site responses while incorporating appropriate constraints based on prior knowledge to ensure solution accuracy. The efficacy of this method has been validated using synthetic data. Specifically, the recorded Pn waves from four underground explosions in North Korea were employed to evaluate the performance of the proposed technique. The derived seismic moment and corner frequency for these events were found to align with the characteristics of the seismic data, earthquake magnitude calculations, and empirical data. The resulting tomographic model of Pn-wave attenuation revealed a spatial distribution of high and low attenuation, indicating significant lithospheric heterogeneity in northeastern China. Areas with low Q0 and low η, such as the Xialiaohe Basin and southwestern Changbai Mountain, suggest a high-temperature environment in the upper mantle cap layer or the presence of molten substances. Conversely, regions with high Q0 and high η, like the northern Changbai Mountain and the vicinity of the eastern Tanlu Fault Zone, characterized by high Pn-wave velocity and thick crust, indicate minimal modification or destruction in the lithosphere. Furthermore, site responses were determined for 75 seismic stations in northeastern China, with their characteristics preliminarily analyzed and interpreted in conjunction with geological context. The iterative process based on the TRR algorithm for Pn-wave spectral inversion proposed in this study demonstrates robust convergence and enhances the fitting accuracy of the observed spectrum. The inversion outcomes from this spectral technique yielded synthetic Pn-wave spectra that closely matched the observed spectra of the four underground explosions in North Korea across various frequency bands for over 90 % of the stations.

Feasibility of an antegrade-retrograde single-sheath inverse technique via vertical puncture in dysfunctional hemodialysis arteriovenous fistula angioplasty

BackgroundStenosis resulting in dysfunctional dialysis access may occur simultaneously on the anastomotic and central venous side. The purpose of this study was to retrospectively evaluate the feasibility of a single sheath inverse technique using the vertical puncture approach to perform bidirectional transvenous percutaneous transluminal angioplasty (PTA) from a single sheath for such dialysis access stenoses.Materials and MethodsTwenty patients (26 cases; 13 males; median age, 74 [range: 50–89] years) who underwent PTA using the sheath inverse technique for dysfunctional arteriovenous fistula stenoses between April 2019 and June 2023 were included. All procedures were performed in an outpatient setting. A 4-cm sheath (4Fr, four cases; 5Fr, 19 cases; 6Fr, three cases) was inserted by vertical puncture through a cutaneous vein in the forearm (20 cases) or upper arm (six cases). After treating one side of the lesion, the sheath was reversed to treat the lesion on the opposite side. The vessel diameter at the sheath insertion site, the success rate of sheath inversion, the number of PTA balloon catheters used, the PTA success rate, adverse events, and primary and secondary patency rates up to one year after PTA were evaluated.ResultsThe median diameter at the sheath indwelling site was 5.2 (range: 3.6–9.5) mm, and sheath inversion was successful in all cases, eliminating the need to place an additional sheath at another site for contralateral stricture treatment. The number of balloon catheters used was one and two in 17 (65%) and eight cases (31%), respectively, and three in one case wherein a drug-coated balloon was used. PTA was successful in all cases and major complications were not observed. However, in one case wherein a sheath had to be placed at the arterial needle puncture site, the skin was hard, leading to difficulty in inversion, and transient venous spasm occurred post-inversion. The primary patency rates at 3, 6 and 12 months after the PTA were 87.5%, 41.7%, and 20.8%, respectively. The secondary patency rates at 6 and 12 months were 100% and 75%, respectively.ConclusionThe single-sheath inverse technique for arteriovenous fistulas was feasible without sheath withdrawal.Graphical

A method for velocity modeling in a volcanic rock zone that integrates the amplitude envelope attribute and grid tomography: application to data from the North Jiangsu Basin

Abstract The complexity of volcanic rocks presents challenges in seismic data quality and fine characterization of structural morphology, making velocity modeling difficult. In this study, we propose a velocity modeling method for volcanic rock areas that combines the use of amplitude envelope attribute and grid tomography inversion. By exploiting the strong reflection characteristics of volcanic rocks, the amplitude envelope attribute is employed to identify volcanic rock structures, eliminating the need for labor-intensive manual interpretation. The grid tomography inversion technique is then used to derive background velocity fields for all strata. These are further refined by incorporating the residual velocity fields of volcanic rocks through fusion and superposition. This integrated approach significantly improves the efficiency and accuracy of velocity modeling in complex volcanic rock areas, overcoming the limitations associated with conventional volcanic rock structural models and resulting in more accurate velocity inversion. The effectiveness and feasibility of the proposed method for velocity modeling in volcanic rock zone are demonstrated through the application of seismic data from an oilfield in eastern China. The results highlight the method's strong industrial application value.

Polymer‐Sorbent Direct Air Capture Contactors with Complex Geometries 3D‐Printed via Templated Phase Inversion

AbstractLow‐cost direct air capture (DAC) systems require efficient gas–solid contactors. These contactors provide rapid rates of heat and mass transport with minimal pressure drops. Triply periodic minimal surfaces (TPMS) are a class of geometries that are shown to have heat transfer properties that exceed those of other geometries, and these benefits are expected to manifest in mass transfer as well due to the analogies between heat and mass transfer. However, creating TPMS contactors is difficult using conventional manufacturing techniques such as injection molding. Non‐solvent‐induced phase separation (NIPS) of a polymeric ink containing the adsorbent is one way to construct adsorption contactors with excellent mass transport rates, but contactors have to date only been fabricated in simple geometries (e.g., films, fibers). This study demonstrates that NIPS of polymeric inks occurs within a simultaneously‐dissolving, water‐soluble, 3D‐printed template. This templated phase inversion (TPI) technique can create seemingly unlimited macroscopic architectures, including TPMS contactors, using a variety of potential DAC adsorbents, including zeolite, silica, activated carbon, and metal–organic frameworks. SEM, micro‐computed tomography, and nitrogen adsorption experiments reveal the microscopic pore structures and macroscopic geometries of the resulting sorbent contactors. TPMS DAC contactors with poly(ethyleneimine)/silica adsorbents are shown to have CO2 capture performances that rival or exceed other contactor geometries.

A Generalized Method for Deriving Steady-State Behavior of Consistent Fuzzy Priority for Interdependent Criteria

Interdependent criteria play a crucial role in complex decision-making across various domains. Traditional methods often struggle to evaluate and prioritize criteria with intricate dependencies. This paper introduces a generalized method integrating the analytic network process (ANP), the decision-making trial and evaluation laboratory (DEMATEL), and the consistent fuzzy analytic hierarchy process (CFAHP) in a fuzzy environment. The Drazin inverse technique is applied to derive a fuzzy total priority matrix, and we normalize the row sum to achieve the steady-state fuzzy priorities. A numerical example in the information systems (IS) industry demonstrates the approach’s real-world applications. The proposed method derives narrower fuzzy spreads compared to the past fuzzy analytic network process (FANP) approaches, minimizing objective uncertainty. Total priority interdependent maps provide insights into complex technical and usability criteria relationships. Comparative analysis highlights innovations, including non-iterative convergence of the total priority matrix and the ability to understand interdependencies between criteria. The integration of the FANP’s network structure with the fuzzy DEMATEL’s influence analysis transcends the capabilities of either method in isolation, marking a significant methodological advancement. By addressing challenges such as parameter selection and mathematical complexity, this research offers new perspectives for future research and application in multi-attribute decision-making (MADM).

Semantic-Electromagnetic Inversion With Pretrained Multimodal Generative Model.

Across diverse domains of science and technology, electromagnetic (EM) inversion problems benefit from the ability to account for multimodal prior information to regularize their inherent ill-posedness. Indeed, besides priors that are formulated mathematically or learned from quantitative data, valuable prior information may be available in the form of text or images. Besides handling semantic multimodality, it is furthermore important to minimize the cost of adapting to a new physical measurement operator and to limit the requirements for costly labeled data. Here, these challenges are tackled with a frugal and multimodal semantic-EM inversion technique. The key ingredient is a multimodal generator of reconstruction results that can be pretrained, being agnostic to the physical measurement operator. The generator is fed by a multimodal foundation model encoding the multimodal semantic prior and a physical adapter encoding the measured data. For a new physical setting, only the lightweight physical adapter is retrained. The authors' architecture also enables a flexible iterative step-by-step solution to the inverse problem where each step can be semantically controlled. The feasibility and benefits of this methodology are demonstrated for three EM inverse problems: a canonical two-dimensional inverse-scattering problem in numerics, as well as three-dimensional and four-dimensional compressive microwave meta-imaging experiments.

3-D parallel anisotropic inversion of controlled-source electromagnetic data using nested tetrahedral grids

SUMMARY Geophysicists today face the challenge of quickly and reliably interpreting extensive controlled-source electromagnetic (CSEM) data sets to map subsurface conductivity structures within realistic geological environments. An ideal 3-D CSEM inversion algorithm using tetrahedral grids should be capable of distinguishing different resolution requirements between forward modelling and inversion grids, have an optimal parallel strategy that fully exploits the inherent independence of CSEM data sets while also possessing the capability to handle large-scale geo-electrical models, and incorporate conductivity anisotropy which should be a common characteristic in realistic subsurface environments. However, existing tools in the geo-electromagnetic community often fall short of these three demands. Addressing this gap, our study introduces a scalable and parallel anisotropic inversion technique for CSEM data, capitalizing on the potential of unstructured tetrahedral grids. We first apply the tetrahedral longest-edge bisection method to create a refined dense, heterogeneous forward modelling grid from a coarse inversion grid. This refinement, focused on areas around transmitters and receivers, is seamlessly integrated within the coarser inversion grid’s topology, enabling precise conductivity mapping and preserving electromagnetic response accuracy during model updates. We further innovate with a source-mesh double-level parallel strategy, utilizing the message passing interface technique for parallel handling of independent CSEM data sets and large-scale geo-electrical models. Externally, we dedicate a processor for inversion model updates employing the Limited-memory Broyden–Fletcher–Goldfarb–Shanno optimization algorithm and divide other processors into groups, each associated with specific transmitting sources and frequencies. Internally, in each group, we employ a domain-decomposition-based scalable and robust iterative solvers using the Auxiliary-Space Maxwell pre-conditioner to parallel quickly calculate the electromagnetic responses from its assigned source-frequency set. Additionally, recognizing the potential for electrical conductivity anisotropy in field data, we incorporate the case of vertical transverse isotropy. We validate the effectiveness of our method through examples, including an isotropic land model with undulating topography, an anisotropic marine model and a real-field data case. Results from both synthetic and field data inversions underscore our method’s significant advancements in efficiency and practicality, particularly in addressing large-scale 3-D CSEM data sets inversion challenges in realistic geological environments.

Anti-Oxidant and Anti-Bacterial Behavior of Sodium Alginate Patches Fortified with Polyurethane and Ag-MOF as Potential Future Wound Healing Material

ABSTRACT Sodium Alginate (SA) is a natural polysaccharide with a high degree of biocompatibility, biodegradability, water absorption properties and stiffness. The inherent brittleness of SA limits its applications in the field of wound healing. The blending of highly flexible polyurethane (PU) with SA could alter the nature of film. In addition, the incorporation of Ag-Metal Organic Framework (Ag-MOF) synthesized via the solvothermal method can help in the enhancement of stability and biological characteristics. The SA and its composite films were obtained through a feasible phase inversion technique. In addition, the Ag-MOF@SA/PU film demonstrates the strongest bacteriostatic impact on E. faecalis and P. aeruginosa, with percentages of approximately 96.9% and 96.41%, respectively. Furthermore, the film demonstrates a radical scavenging efficiency of 83.96%. Moreover, the Ag-MOF@SA/PU film exhibited a significant increase in the production of oxidative stress, attaining a value of 84.89%. Owing to the results, Ag-MOF@SA/PU was taken for in-vitro degradability analysis and visible surface erosion was observed over time. Thus, the Ag-MOF@SA/PU film could be considered for future wound healing therapy.

PNN Enhanced Seismic Inversion for Porosity Modeling and Delineating the Potential Heterogeneous Gas Sands via Comparative Inversion Analysis in the Lower Indus Basin

Seismic inversion has been in use for the last two decades to measure inverted impedances using an integrated data set approach. This research focuses on the application of multi-attribute seismic inversion and the geostatistical probabilistic neural network (PNN) approach for determining rock properties and litho-fluid classification in the Mehar-Mazarani Field of the Lower Indus Basin (LIB), Pakistan. The study compares five different inversion techniques, including model-based inversion (MBI), colored inversion (CI), linear sparse spike inversion (LSSI), band-limited inversion (BLI), and maximum likelihood sparse spike inversion (MLSSI). The inverted outputs, such as acoustic P-impedance (Zp), density (ρ), porosity (φ), and shale volume (Vsh), were analyzed in Paleocene and Cretaceous geological complex reservoirs to identify gas-bearing zones. The results indicated the existence of gas between 1630 and 1700 ms (ms) and corresponding depth ranges from approximately 3200 m up to 4200 m with varying thickness. Amongst the inversion techniques, MBI demonstrated greater accuracy, with inverted density volumes showing a strong correlation coefficient of 0.98 and the lowest root mean square error (RMSE) and relative error of 0.10 m/s * g/cc. A geostatistical PNN approach was employed to estimate variations in Vsh and φ within the sand reservoir. MBI again yielded more reliable results, with a strong correlation between the measured and inverted attributes. High φ and low Vsh were observed in predetermined low-impedance zones. Overall, MBI is proven to be the most accurate and reliable technique, providing clear identification of the gas occurrence. This research highlights the effectiveness of seismic inversion, particularly the application of MBI, in determining rock properties and identifying gas-bearing zones within the Mehar-Mazarani gas field.

Characterizing dispersion in bovine liver using ARFI-based shear wave rheometry

Background: Dispersion presents both a challenge and a diagnostic opportunity in shear wave elastography (SWE). Shear Wave Rheometry (SWR) is an inversion technique for processing SWE data acquired using an acoustic radiation force impulse (ARFI) excitation. The main advantage of SWR is that it can characterize the shear properties of homogeneous soft media over a wide frequency range. Assumptions associated with SWR include tissue homogeneity, tissue isotropy, and axisymmetry of the ARFI excitation). Objective: Evaluate the validity of the SWR assumptions in ex vivo bovine liver. Approach: SWR was used to measure the shear properties of bovine liver tissue as function of frequency over a large frequency range. Assumptions associated with SWR (tissue homogeneity, tissue isotropy, and axisymmetry of the ARFI excitation) were evaluated through measurements performed at multiple locations and probe orientations. Measurements focused on quantities that would reveal violations of the assumptions. Main results: Measurements of shear properties were obtained over the 25–250 Hz range, and showed a 4-fold increase in shear storage modulus (from 1 to 4 kPa) and over a 10-fold increase in the loss modulus (from 0.2 to 3 kPa) over that decade-wide frequency range. Measurements under different conditions were highly repeatable, and model error was low in all cases. Significance and Conclusion: SWR depends on modeling the ARFI-induced shear wave as a full vector viscoelastic shear wave resulting from an axisymmetric source; it is agnostic to any specific rheological model. Despite this generality, the model makes three main simplifying assumptions. These results show that the modeling assumptions used in SWR are valid in bovine liver over a wide frequency band.

Nonlinear dynamic inversion based full envelope robust flight control for coaxial compound helicopter

The flight control system of coaxial compound helicopters (CCHs) is a complex multi-variable system characterized by redundant control effectors, strong nonlinear characteristics, and multiple flight modes. This paper presents a unified robust control framework tailored for CCH full-envelope flight, utilizing nonlinear dynamic inversion and extended state observer techniques. The framework is specifically designed to tackle issues arising from a multi-mode nature, parametric uncertainties, and external disturbances. Within the unified framework, the study addresses inherent complexities such as nonlinearities and cross-coupling effects in CCH by leveraging nonlinear dynamic inversion to formulate flight control laws for both inner and outer-loops. To mitigate model uncertainties and external disturbances, the extended state observer is employed to estimate lumped disturbance effectively. Control allocation for both inner and outer-loops is devised to adapt to changes in control effector authorities and flight modes. Furthermore, an exponential control allocation strategy is proposed for the outer-loop to ensure a smooth pitch angle during transition flight. The effectiveness of the proposed control laws and control allocation strategies in achieving precise attitude tracking, transition flight and mission task elements (MTEs), even in the presence of notable model uncertainties and external disturbances, is demonstrated through numerical simulations.

Kinematic Source Properties of the 2023 Mw 7.7 Türkiye Earthquake Inferred from Near-Fault Strong Ground Motions

Abstract The 2023 Mw 7.7 Türkiye earthquake provided densely observed near-fault ground-motion data, which enabled us to investigate their characteristics and generations. This study aimed to obtain an intuitive understanding of the characteristics of near-fault strong ground motions and their relationship with kinematic source properties using a simple source model. Synthetic ground motions were calculated using the discrete wave number method and compared with observed ground motions. The observed strong motions were used after a time correction based on the first P-wave arrival. Results showed that near-fault pulse-like velocities (0.02–0.6 Hz) were generally explained by the simple kinematic source model that assumed a continuous rupture propagation along the faults. Comparisons at individual sites indicate the various rupture properties of the fault segments. Near-fault ground motions along the Narli segment were explained by the fault plane along the surface trace and not by aftershock distribution. A supershear rupture propagation speed is necessary for a part of the Amanos segment. Rupture stops and restarts were implied near the stepover along the Amanos segment. Empirical site factors estimated by generalized inversion techniques did not show peaks around the frequency of observed large velocity pulses, indicating that the velocity pulses were mainly generated by the source. The model bias and uncertainties were also examined to supplement the simplified subsurface structure used in the simulation. Our results will help to associate the qualitative and quantitative aspects of the kinematic source process with near-fault strong ground motions.

Desalination Performance Evaluation of hBN@UiO‐66 MOF Incorporated Hollow Fiber Membrane using Membrane Distillation

AbstractIn the present study, the polyvinylidene fluoride (PVDF) modified hollow fiber (HF) membranes have been synthesized by dry‐jet wet phase inversion technique for desalination via direct contact membrane distillation (DCMD). UiO‐66 metal‐Organic framework (MOF) and surface‐modified UiO‐66 with h‐BN nanomaterial have been incorporated with PVDF‐HF membrane. The various analytical methods like FE‐SEM, FTIR, PXRD, TGA, tensile strength, were used to characterize prepared MOF and HF membranes. It was observed from DCMD results that the h‐BN@UiO‐66/PVDF (M3) HF membrane gives higher flux than UiO‐66/PVDF (M2) and pure PVDF (M1) membrane. In the present investigation, response surface methodology (RSM) by box‐behnken design (BBD) was used to optimize the DCMD system and evaluate the behavior of operating parameters such as feed temperature, feed concentration, and feed flow rate. The optimum operating values of feed temperature, feed flow rate, and feed concentration were found as 65 °C, 1 LPM, and 1.5 wt.%, respectively. Under optimum conditions, the M3 HF membrane gives the highest flux of 26.78 L/m2 ⋅ h compared to M2 and M1 membranes. During DCMD, salt rejection is almost greater than 99.8 % for all prepared membranes. Other salts like potassium chloride (KCl), Magnisium Sulphate (MgSO4), and calcium sulphate (CaSO4) are also used to check salt rejection of all membranes at optimum operating conditions. Moreover, the M3 membrane exhibits stable permeate flux and high salt rejection (&gt;99.9 %) at optimized process parameters over 80 h running. Overall, the present study provides the positive effects of h‐BN nanoparticles and UiO‐66 MOF on HF membrane to improve performance in DCMD.

Crucial time of emergency monitoring for reliable numerical pollution source identification

The Pollution source identification (PSI) is an important issue on river water quality management especially for urban receiving water. Numerical inversion method is theoretically an effective PSI technique, which employs monitored downstream pollutant breakthrough curves to identify the pollution source. In practice, it is important to know how much monitoring data should be accumulated to provide PSI results with acceptable accuracy and uncertainty. However, no literature reports on this key point and it seriously handers the numerical PSI technology to mature practical applications. To seek a monitoring guideline for PSI, we conducted extensively numerical experiments for single-point source instantaneous release taking Bayesian-MCMC method as the baseline inversion technique. The crucial time (Tc) phenomenon was found during the data accumulation process for Bayesian source inversion. After Tc, estimated source parameters subsequent sustained low error levels and uncertainty convergence. Results shown the presence of Tc impacted by the number and location of monitoring sections, while monitoring frequency and data error do not. Under different river hydrodynamic conditions, relative crucial time (Λ) is determined by the river's Peclet number, and minimum effective Λ was controlled by dispersion coefficient (Dx). Analytic spatial structure of Λ(U, Dx) was uncovered and this relationship successfully explained by the information entropy theory. Based on these findings, a novel design method of PSI emergency monitoring network for preparedness plan and a practical framework of PSI for emergency response were established. These findings fill the important knowledge gap in PSI applications and the guidelines provide valuable references for river water quality management.