Separate Mesh Research Articles

Facilitating Large-Amplitude Motions of Wave Energy Converters in OpenFOAM by a modified Mesh Morphing Approach

High-fidelity simulations using computational fluid dynamics (CFD) for wave-body interaction are becoming increasingly common and important for wave energy converter (WEC) design. The open source finite volume toolbox OpenFOAM is one of the most frequently used platforms for wave energy. There are currently two ways to account for moving bodies in OpenFOAM: (i) mesh morphing, where the mesh deforms around the body; and (ii) an overset mesh method where a separate body mesh moves on top of a background mesh. Mesh morphing is computationally efficient but may introduce highly deformed cells for combinations of large translational and rotational motions. The overset method allows for arbitrarily large body motions and retains the quality of the mesh. However, it comes with a substantial increase in computational cost and possible loss of energy conservation due to the interpolation. In this paper we present a straightforward extension of the spherical linear interpolation (SLERP) based mesh morphing algorithm that increase the stability range of the method. The mesh deformation is allowed to be interpolated independently for different modes of motion, which facilitates tailored mesh motion simulations. The paper details the implementation of the method and evaluates its performance with computational examples of a cylinder with a moonpool. The examples show that the modified mesh morphing approach handles large motions well and provides a cost effective alternative to overset mesh for survival conditions.

Special wettable Azadirachta indica leaves like microarchitecture mesh filtration membrane produced by galvanic replacement reaction for layered oil/water separation

The oil/water separation has received significant attention due to its critical environmental impact. The special wettable surfaces are highly desired to deal with the oil/water mixtures. This work demonstrates a simple two-step method to develop a superhydrophobic Azadirachta indica leaves like Ag-decorated electrochemically copper-coated stainless-steel mesh (SH-AIL-Ag-EC-Cu-Mesh) for efficient separation of oil/water mixtures. In the first step, the electrodeposition of the copper took place on the mesh surface at a suitable applied potential. In the second step, the galvanic replacement reaction between the Ag+ and electrodeposited Cu produced the fascinating superhydrophobic Ag leaves on the mesh surface. The SH-AIL-Ag-EC-Cu-Mesh was thoroughly characterized by the X-ray photoelectron spectroscopy (XPS), Energy Dispersive X-Ray Spectroscopy (EDX), elemental mapping, surface wettability analysis, and the contact analyzer. The morphological analysis has shown the unique leafy structures of the reduced Ag on the surface of the mesh. The XPS analysis has confirmed that most of the Ag present on the surface is in zerovalent form. The combination of the electrodeposition and the displacement reaction between the copper and the silver turned the surface superhydrophobic, and the water contact angle was significantly improved from 115° to 158°. The designed SH-AIL-Ag-EC-Cu-Mesh has shown excellent selectivity for oil in oil/water mixtures with a separation efficiency of 99.1% with an exceptionally high flux of 8963 L m−2h−1. The SH-AIL-Ag-EC-Cu-Mesh has shown excellent reusability, and after 15 cycles of separation, no significant decrease in the oil/water separation efficiency was observed.

Facile approach to fabricate a high-performance superhydrophobic PS/OTS modified SS mesh for oil-water separation

Special wetting materials have been used for the oil and water separation due to their different interfacial attraction of oil and water. Herein, we successfully fabricated superhydrophobic coatings on stainless steel (SS) mesh by depositing successive layers of polystyrene (PS) and octadecyltrichlorosilane (OTS) through the dip-coating method. The as-prepared coating showed a water contact angle (WCA) of 157.5 ± 2°, a rolling angle of 6 ± 2° and an oil contact angle (OCA) of around 0°. The surface microstructure analysis of the coating revealed a regular pattern of microscale bumps with nanoscale folds on it, both of which improve the overall superhydrophobicity of the surface. The capacity of coatings to separate oil and water was examined by employing a variety of mixtures of oil and water, including petrol, diesel, kerosene, vegetable oil, and coconut oil. In case of low viscosity oil, the coated mesh demonstrated separation effectiveness of more than 97% and on the other hand, high viscosity oil demonstrated just 89% efficiency. Low viscosity oils showed a greater permeation flux through the mesh than extremely viscous oil. The mechanical strength of the coating was examined using bending, twisting, adhesive tape testing, sandpaper abrasion tests, and the findings indicated that coated mesh had exceptional mechanical resilience. In addition, the developed superhydrophobic mesh demonstrated excellent thermal stability and self-cleaning properties. Therefore, this superhydrophobic/superoleophilic mesh has a significant deal of application potential in practical.

Multi-meshing-state and disengaging-proportion analyses of a gear-bearing system considering deterministic-random excitation based on nonlinear dynamics

Backlash induces gear-teeth separation or back-side tooth mesh (BTM), resulting in gear disengagement (GD), which heavily aggravates the dynamic performance and transmission quality of gear drivetrains. This study focuses on the disengaging proportion (DP) characteristics of a gear- bearing systems based on a multi-meshing-state (MMS) model. A new nonlinear dynamic model of gear-bearing system with MMS and deterministic-random external excitation is established considering the synergistic effect of backlash and non-integer contact ratio. A modified time-varying mesh stiffness with temperature stiffness is included in the model. Afterwards, the effect of the gear pair meshing vibration on bearing radial vibration is studied. The bifurcation and evolution of the MMS behavior are investigated changing the system parameters. An algorithm of DP is proposed in the time domain based on the established MMS model. The characteristics of DP are systematically discussed with the effects of dynamic response type, phase trajectory topology, bifurcation and chaos, and correlation between parameters. The results demonstrate that grazing bifurcation reduces the number of GD and chaos is prone to BTM. The disengaging proportion is highly dependent on the phase trajectory topology and generally increases from period-1 to quasi-periodic and then to chaotic responses. Bifurcation changes the variation trend of DP, thus there is a peak near period-doubling bifurcation and a trough near grazing bifurcation. The chaotic response leads to a jump in DP. The correlation between parameters considerably dominates the DP. This study provides a reference for revealing the mechanism of gear system disengagement and improving the dynamic performance.

Underwater superoleophobicity of poly(vinyl alcohol) gel-coated/micro-arc oxidized Al mesh for oil-water separation

In response to the fact that oil removal materials were easily contaminated by viscous oil, materials with easy cleaning ability and long-term efficiency were developed for oil-water separation in this study. The ceramic coating was prepared on the surface of aluminum mesh by the micro-arc oxidation (MAO) method, and poly (vinyl alcohol) gel (PVA) was used to cover the MAO Al mesh. PVA@MAO Al mesh with subsea oil repellent function was prepared. As expected, PVA@MAO Al mesh exhibited good “hydrophilic” properties in the air and “oleophobic” properties underwater. The synthetic PVA@MAO Al mesh exhibited good self-cleaning properties, chemical stability, and abrasion resistance. Compared with the traditional oil-water separation method, this method has a simple preparation process, low cost, and excellent performance. These properties make PVA@MAO Al mesh ideal for oil-water separation. It has wide application prospects in oil spill cleanup, wastewater treatment, and water purification.

Predicting Fatigue Crack Growth Behavior of Coalesced Cracks Using the Global-Local Superimposed Technique

The S-version Finite Element Method (FEM) is known as a global-local superimposed approach that consists of two separate meshes referred to as global and local cracks. The relationship between the energy release rate and the Stress Intensity Factor (SIF) is evaluated to characterize the growth behavior of the fatigue cracks. The SIF is determined using the Virtual Crack Closure Method (VCCM). The cracks propagated in the direction of the loading before coalescing into a single crack. Each crack begins with a length of 10mm and a depth of 3mm. After the crack coalesces, the diameter of the surface crack before it breaks is 28mm, whereas the depth of the crack is 5.3mm. The V-shaped surface crack forms quickly after coalescence occurs and continues to propagate into a massive semi-elliptical surface crack before finally breaking. The result was validated and compared between S-version FEM and the analytical solution. The behavior of the fatigue crack growth shows a good agreement between both methods with small errors. The result indicates that the Root Mean Square Error (RMSE) values before coalescing are 0.1496 with 0.6, and after coalescing is 0.4, the RMSE value is 0.1665. Therefore, it can be stated that the S-version FEM approach can predict the growth of fatigue cracks.

Fabrication of superhydrophobic stainless-steel mesh for oil-water separation by jet electrodeposition

A method for fabricating superhydrophobic stainless-steel meshes based on magnetic field-assisted jet electrodeposition is proposed. Ferromagnetic nickel particles (Nip) were added to the electroplating solution to prepare Ni/Nip coatings with mountain-like rough structure on stainless-steel meshes, followed by application of a parallel magnetic field in the cathode region. Magnetic fields play an indispensable role in the preparation of coatings. Exposure to air for 6 days resulted in a spontaneous switch of the coating from superhydrophilicity to superhydrophobicity and exhibited superoleophilicity. X-ray photoelectron spectroscopy revealed that this transition in wettability was related to spontaneous adsorption of hydrocarbons in the air induced by the coating. Based on the superhydrophobicity and superoleophilicity of the as-prepared Ni/Nip-coated meshes, high-efficiency, high-throughput, and high-purity separation of oil-water mixtures was achieved with a 300-mesh mesh. Furthermore, the as-prepared meshes continue to exhibit a separation efficiency greater than 97.0% and stable reusability even after 50 repeated separations.

Facile Construction and Fabrication of a Superhydrophobic and Super Oleophilic Stainless Steel Mesh for Separation of Water and Oil.

The fluoride-free fabrication of superhydrophobic materials for the separation of oil/water mixtures has received widespread attention because of frequent offshore oil exploration and chemical leakage. In recent years, oil/water separation materials, based on metal meshes, have drawn much attention, with significant advantages in terms of their high mechanical strength, easy availability, and long durability. However, it is still challenging to prepare superhydrophobic metal meshes with high-separation capacity, low costs, and high recyclability for dealing with oil–water separation. In this work, a superhydrophobic and super oleophilic stainless steel mesh (SSM) was successfully prepared by anchoring Fe2O3 nanoclusters (Fe2O3-NCs) on SSM via the in-situ flame synthesis method and followed by further modification with octadecyltrimethoxysilane (OTS). The as-prepared SSM with Fe2O3-NCs and OTS (OTS@Fe2O3-NCs@SSM) was confirmed by a field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), energy dispersive spectrometer (EDS), X-ray photoelectron spectrometer (XPS), and X-ray diffractometer (XRD). The oil–water separation capacity of the sample was also measured. The results show that the interlaced and dense Fe2O3-NCs, composed of Fe2O3 nanoparticles, were uniformly coated on the surface of the SSM after the immerging-burning process. Additionally, a compact self-assembled OTS layer with low surface energy is coated on the surface of Fe2O3-NCs@SSM, leading to the formation of OTS@Fe2O3-NCs@SSM. The prepared OTS@Fe2O3-NCs@SSM shows excellent superhydrophobicity, with a water static contact angle of 151.3°. The separation efficiencies of OTS@Fe2O3-NCs@SSM for the mixtures of oil/water are all above 98.5%, except for corn oil/water (97.5%) because of its high viscosity. Moreover, the modified SSM exhibits excellent stability and recyclability. This work provides a facile approach for the preparation of superhydrophobic and super oleophilic metal meshes, which will lead to advancements in their large-scale applications on separating oil/water mixtures.

Immediate changes in intra-abdominal pressure and lung indicators in patients undergoing complex ventral hernia repair with the transversus abdominis muscle release, with and without preoperative botulinum toxin.

The current treatment of complex ventral hernias involves muscle closure with components separation techniques and mesh placement. The purpose of this study is to evaluate the immediate postoperative changes in the intra-abdominal pressure (IAP), and lung indicators after treatment of complex ventral hernias with the transversus abdominis reléase (TAR) technique. All patients with complex ventral hernias treated between November 28th, 2016 and October 6th, 2021 were initially included. We excluded patients with lung and/or heart comorbidities. A total of 43 patients were studied, measuring IAP, lung compliance, pulmonary plateau pressure (PPP), and end-tidal CO2 before and after surgical treatment. Median IAP increased from 5to 9mmHg (p < 0.0001), and PPP from 11to 12mmHg (p = 0.004). Increased body mass index (BMI) was associated to a PPP increase above normal values. Postoperative changes were not different in patients receiving preoperative preparation with botulinum toxin. After complex ventral hernia closure, there is an immediate impact on IAP and PPP, the latter more frequent in patients with the highest BMI, and this maynot be prevented by the preoperative administration of botulinum toxin.

Multilayered chitosan/kaolin@calcium carbonate composite films with excellent chemical and thermal stabilities for oil/water filtration realized by a facile layer-by-layer assembly

Herein, a novel separation mesh membrane with chitosan/kaolin@calcium carbonate (CS/KL@CaCO3) coating was fabricated via a facile and eco-friendly approach. Owing to the hierarchical micro/nano-structure and high hydrophilicity of the composite coating, the decorated membrane demonstrates outstanding superhydrophilicity in air and underwater anti-oil-fouling capability. The membrane can realize efficient separation to various light oil/water mixtures, and the separation efficiencies are >98.0%. Especially, there is no obvious change in the separation efficiency after the reuse of 80 cycles, suggesting its good recyclability. In addition, the membrane displays satisfactory corrosion resistance and hot water resistance, and is applicable for the removal of corrosive solutions or hot water in oils. The high separation efficiency, excellent oil-repelling capability underwater, and readily scaled-up fabrication procedure of the membrane suggest enormous application potential in dealing with oil spills and separating oily wastewater.

Facile Preparation of Novel Stainless-steel Mesh for Efficient Separation of FOG (Fat, Oil and Grease) and Water

Facile Preparation of Novel Stainless-steel Mesh for Efficient Separation of FOG (Fat, Oil and Grease) and Water

Facile fabrication of multi superlyophobic nano soil coated-mesh surface with excellent corrosion resistance for efficient immiscible liquids separation

A novel strategy for spraying nanosized soil particles on steel mesh to prepare the superlyophobic soil mesh by a facile surface treatment technology, and successfully apply it to various immiscible liquids separation. • A multifunctional, sustainable material for immiscible liquid mixtures separation. • Under nonpolar (polar) liquid superlyophobicity of polar (nonpolar) liquid. • Used chemical properties-structure relationships to give material performance. • Low cost manufacturing, environment friendly, dimplicity of operator. • Good corrosion resistance in acidic, alkaline and high salt environment. Immiscible liquids separation has recently become a worldwide challenge due to the expanding industrial activity. It is still thorny to put forward a universal strategy for constructing multi-superlyophobic surfaces in immiscible liquids systems due to a thermodynamic contradiction. Herein, a low-cost, environmentally friendly pre-wetted nanosized soil coated-mesh (NSCM) was prepared, which shows the property of under-nonpolar-liquid superlyophobic to polar liquid, or under-polar-liquid superlyophobic to nonpolar liquid. The NSCM was fabricated in aqueous solutions by spraying melamine formaldehyde resin modified nanosized soil particles on a stainless-steel mesh for selective immiscible liquid separation. After the NSCM is prewetted with heavy liquid, heavy liquid can be removed from the light immiscible liquid mixtures by gravity. The as-prepared NSCM showed a high separation efficiency of above 99% for a series of immiscible liquids mixtures, even after 60 separation cycles. More importantly, the electrochemical tests indicated that the NSCM exhibited the outstanding durability after being immersed in alkali (pH = 10.0, NaOH), acidic (pH = 4.0, HCl) and high-concentrated salt solutions (3.5 wt% NaCl) for 30 days. The calculated R t values were approximately 1.04 × 10 7 , 2.65 × 10 6 and 7.59 × 10 5 Ω·cm 2 , respectively. And the corresponding corrosion rates were 0.013712, 0.96438, and 2.5818 μm/year, respectively. These excellent performances of the NSCM make it an ideal candidate material for separation, and even in a wider field of sea wastewater treatment.

A Finite Element Mesh Regrouping Strategy-Based Hybrid Light Transport Model for Enhancing the Efficiency and Accuracy of XLCT.

X-ray luminescence computed tomography (XLCT) is an emerging hybrid imaging modality in optical molecular imaging, which has attracted more attention and has been widely studied. In XLCT, the accuracy and operational efficiency of an optical transmission model play a decisive role in the rapid and accurate reconstruction of light sources. For simulation of optical transmission characteristics in XLCT, considering the limitations of the diffusion equation (DE) and the time and memory costs of simplified spherical harmonic approximation equation (SPN ), a hybrid light transport model needs to be built. DE and SPN models are first-order and higher-order approximations of RTE, respectively. Due to the discontinuity of the regions using the DE and SPN models and the inconsistencies of the system matrix dimensions constructed by the two models in the solving process, the system matrix construction of a hybrid light transmission model is a problem to be solved. We provided a new finite element mesh regrouping strategy-based hybrid light transport model for XLCT. Firstly, based on the finite element mesh regrouping strategy, two separate meshes can be obtained. Thus, for DE and SP N models, the system matrixes and source weight matrixes can be calculated separately in two respective mesh systems. Meanwhile, some parallel computation strategy can be combined with finite element mesh regrouping strategy to further save the system matrix calculation time. Then, the two system matrixes with different dimensions were coupled though repeated nodes were processed according to the hybrid boundary conditions, the two meshes were combined into a regrouping mesh, and the hybrid optical transmission model was established. In addition, the proposed method can reduce the computational memory consumption than the previously proposed hybrid light transport model achieving good balance between computational accuracy and efficiency. The forward numerical simulation results showed that the proposed method had better transmission accuracy and achieved a balance between efficiency and accuracy. The reverse simulation results showed that the proposed method had superior location accuracy, morphological recovery capability, and image contrast capability in source reconstruction. In-vivo experiments verified the practicability and effectiveness of the proposed method.

ZnO/WO3.H2O micro-nanostructures coated mesh for efficient separation of oil-water mixture

In this work, we report the fabrication of superhydrophilic-underwater superoleophobic ZnO/WO3.H2O coated stainless steel mesh for the effective oil-water separation. X-ray diffraction studies confirm the occurrence of hexagonal wurtzite and orthorhombic phase of ZnO and WO3.H2O respectively in the ZnO/WO3.H2O coated mesh. The superhydrophilic-underwater superoleophobic nature of ZnO/WO3.H2O covered mesh is attributed to the innate hydrophilicity and surface roughness of WO3.H2O, which is again enhanced by the inclusion of ZnO. The oil-water separation efficiency of ZnO/WO3.H2O covered stainless steel mesh was over 98% for various oil-water mixtures. The coated mesh maintains high efficiency of separation even after 10 cycles of operation. Moreover, the as-deposited meshes demonstrated good separation ability for the emulsified oil droplets larger than its pore size. The excellent abrasion-resistant ability of ZnO/WO3.H2O coated mesh indicate its excellent mechanical stability. In addition, the high intrusion pressure of ZnO/WO3.H2O coated mesh favors the separation of oil-water mixture in large volumes. Furthermore, the photocatalytic activity of the coated mesh could degrade the organic pollutants present in the oil-water mixture. The proposed novel strategy in designing a multifunctional surface paves the way for the treatment of oleaginous water for environmental remediation.

Synergistic effect of nano-silica and eco-friendly hydrogel for the cost-effective and highly efficient oil-water separation

Reported herein is a novel eco-friendly and low-cost oil-water separation mesh that can achieve a high separation efficiency up to 99%, while the prepared mesh maintained excellent performance even after immersion in salty water for 5 days, or cycle use for 20 times. The superhydrophilic and underwater superoleophobic mesh was modified with a layer of rough nano silica by soot template method firstly, and then the mesh was covered with the calcium alginate hydrogel coating via a simple dip-coating method. The synergistic effect of the low-cost nano-silica and environmentally friendly calcium alginate hydrogel not only endowed the mesh with outstanding oil-water separation performance but also overcame the shortcoming of high-cost and pollutive in the fabrication of oil-water separation materials. The prepared mesh maintained excellent oil-water separation efficiency and water permeation flux, even after treatment in various harsh environments. The cost-effective and eco-friendly oil-water separation mesh holds great potential in the treatment of industrial and domestic waste oil.

Environmentally benign and durable superhydrophobic coatings based on short fluorocarbon chain siloxane modified halloysite nanotubes for oil/water separation

Fluorinated siloxane (F-Si(OCH 3 ) 3 ) was synthesized from perfluoro (2-methyl-3-oxyhexyl) fluorine and N- (β-aminoethyl) -γ-aminopropyltrimethoxy silane, and then was used for hydrophobic modification of halloysite nanotubes (F-HNTs). A mixture of epoxy resin and F-HNTs was sprayed onto the surface of the stainless steel mesh. F-HNTs enhanced the surface roughness and reduced the surface energy, giving the mesh superhydrophobic/superlipophilic properties. The static water contact angle of coated mesh can reach 155.4 ± 0.3°. A series of oil and water mixtures can be separated, and the separation efficiency was higher than 97.8 ± 0.3%. After 50 cycles, the separation efficiency was still higher than 96.2 ± 0.5%. The coating mesh also had high separation efficiency for oil-water mixtures with different volume ratios and pH values. More importantly, the coated mesh still showed good stability in the harsh test conditions, such as strong acid, strong alkali, sand-paper wear and so on. Since the preparation of the coated mesh has the advantages of simplicity, scalability, and economy, it is expected to be applied on a large scale in the field of oil-water separation in the future. • Fluorosiloxane modified HNTs was used for fabricating superhydrophobic coatings. • Modified HNTs/epoxy was sprayed on the stainless steel mesh for oil-water separation. • This coated mesh has excellent separation efficiency and separation flux. • The coated mesh exhibited excellent stability under harsh external conditions.

Structured Copper Mesh for Efficient Oil-Water Separation Processed by Picosecond Laser Combined With Chemical Treatment or Thermal Oxidation

Oil-water separation has great practical significance, and can be used to help cope with growing oily industrial sewage discharge or marine oil spills, avoiding water pollution. Smart artificial super-wettable materials used for oil-water separation have aroused enormous interest because of their advantages of energy efficiency and applicability across a wide range of industrial processes. Herein, we report a highly efficient, simple method for oil-water separation using copper mesh fabricated by picosecond laser processing combined with chemical treatment or thermal oxidation. After laser processing, the surfaces of copper mesh show superhydrophilicity (hydrophilicity) and underwater superoleophobicity, which can be used to separate water from oil. While, for the samples after laser and chemical treatment or laser treatment combined with thermal oxidation, the surfaces become superhydrophobic (hydrophobic) and underwater superoleophilic, which can separate oil from water. Moreover, these three kinds of super-wettability meshes show high separation efficiency, achieving more than 99% seperation. Furthermore, the as-prepared mesh can be used for various oil-water mixture separation, such as edible oil, kerosene, diesel, and so on. Thus, this work will provide insights for controllable oil-water separation, and will also be beneficial to the study of microfluidic devices, and smart filters.

Fabrication of superhydrophobic nano-soil coated surfaces for oil/water separation and metal corrosion protection

Low-cost and scalable fabrication processes are needed to prepare efficient superhydrophobic materials, particularly for oil/water separation and metal protection against severe oil spills and metal corrosion. Here, an effective oil/water separation mesh with long-lasting acid/base durability and corrosive resistance is reported. In this work, the mesh was fabricated by simply spraying nano soil particles cross-linked with melamine resin and impregnating them with polyethylene (PE) solution. The multi-layered morphology obtained from the spraying and impregnating process which provides the unique wetting properties for the stainless steel (SS) mesh, such as superhydrophobicity and low water adhesion. Also the low chemical activity of alkyl sp3 carbon-hydrogen bonds provides acid/base resistance for the manufactured material. By utilizing these unique properties, not only can gravity-driven efficient oil/corrosive fluid separation be achieved, but the fabricated superhydrophobic stainless steel (SSS) mesh retains high separation efficiency (> 99%) and superhydrophobicity (water contact angle, WCA > 150°) in reuse process of wastewater in treated oil. More importantly, this excellent protection can effectively reduce the corrosion rate of the mesh by more than two orders of magnitude (SS mesh icorr 1.82 × 10−8 A·cm−2; SSS mesh icorr 9.84 × 10−11 A·cm−2) which providing a long-lasting protection even after 16 days of immersion in 3.5 wt% NaCl solution. All in all, the easy operation, acid/base resistance, high separation efficiency, and corrosion inhibition efficiency of the SSS mesh give them great potential for oil/water separation and metal protection applications.

Simultaneous Early Surgical Repair of Post-Cholecystectomy Major Bile Duct Injury and Complex Abdominal Evisceration: A Case Report

Background: Major bile duct injuries (BDIs) are hazardous complications after laparoscopic cholecystectomy (0.4%-0.6% of all laparoscopic cholecystectomies) [1, 2-4]. Major BDIs usually require surgery, ideally either within one week or after 3 three months after index surgery [1]. We describe the case of iatrogenic transection of the common bile duct (CBD) complicated by a complex full midline abdominal evisceration presented on day 12 after emergency laparotomy for biliary peritonitis. Case Presentation: A 65-year-old male underwent laparoscopic cholecystectomy in a district general hospital and was discharged on the same day, following apparently uneventful surgery. He, however, re-presented two days later with biliary peritonitis when emergency ERCP showed full CBD transection. The local surgical team performed midline exploratory laparotomy, washout, and external drainage aside the leaking CBD and referred the case to our tertiary HPB service. While awaiting transfer (due to bed shortage), full wound dehiscence occurred. On transfer arrival at our HPB service on postoperative day 11, the patient presented extensive evisceration with loss of domain and persisting high-volume biliary spillage aside bowels. Following assessment and fast literature review, we considered operation undeferrable and planned multi-stage surgeries, including primary Roux-en-Y hepaticojejunostomy (HJ) and progressive abdominal wall closure in multiple sessions under general anaesthesia, aided by vacuum-assisted wound closure and intraperitoneally mesh-mediated fascial traction-approximation (VAWCM) with permeable mesh. An expected late incisional hernia was eventually repaired through component separation and biological mesh. Discussion and Conclusion: The complexity of our case lies in the coexistence of 2-weeks biliary peritonitis following early BDI with massive midline evisceration, in combination, both representing over 40% mortality risk, requiring immediate, simultaneous repair. Roux-en-Y HJ and VAWCM have proven safe and effective.

Template Preparation and Experimental Study on Superhydrophilic-Superoleophobic Nano-structures Surfaces Based on Titanium Mesh Membrane

With the development of industrial process, the crude oil leakage of industrial oil wastewater is increasingly serious. The development of efficient and environmentally friendly separation mesh membrane technology is the best way to solve the water pollution problem. With the rapid development of micro-nanotechnology, the wetting change caused by surface structure (micro-nano scale) that can solve the problem of fabrication for oil-water separation mesh. If the liquid contact angle at the surface is less than 10°, the surfaces are called superhydrophilic surfaces. Meanwhile, the liquid contact angle is greater than 150°, the surfaces are called superhydrophobic surface. Surface with superhydrophilic/superhydrophobic is also known as special wetting surfaces. The special wetting surface is fabricated by coating / spraying. The process is simple and easy to operate. By constructing the multi-stage surface roughness and reducing the surface energy, the titanium mesh with different orders are used as the base. the mesh membrane with special superhydrophilic-superoleophobic properties is constructed. Comparing the influence of titanium mesh with different molybdenum numbers (mesh size) on hydrophilic/ hydrophobicity, the mechanism of the macroscopic size of the pore spacing substrate on the special surface wetting is analyzed. The preparation of ultra-hydrophobic multi-stage surface roughness titanium mesh is realized. The experimental analysis of oil and water separation effect is carried out. For the preparation of high-efficiency oil-water separation mesh film that can be used in industrial production. The oil and water separation mesh membrane was prepared by the titanium mesh substrate to achieve effective oil and water separation.