Sulfuryl fluoride (SOF, SF) is an effective and increasingly popular fumigant for treating buildings and commodities in international trade but has come under scrutiny as a potent greenhouse gas. Passage of vent gases through an alkaline spray has been proposed for scrubbing SF, but base hydrolysis is insufficiently fast and generates equal yields of fluoride and fluorosulfate, the latter of unknown environmental hazard. We report here that alkaline hydrogen peroxide (HO) markedly accelerates SF removal and gives nearly quantitative yield of fluoride, with fluorosulfate produced in less than 3.
View Article and Find Full Text PDFElectrochemical advanced oxidation processes (EAOPs) have shown great promise for treating industrial wastewater contaminated with phenolic compounds. However, the presence of chloride in the wastewater leads to the production of undesirable chlorinated organic and inorganic byproducts, limiting the application of EAOPs. To address this challenge, we investigated the potential of incorporating Fe(II) and Fe(III) into the EAOPs with a boron-doped diamond (BDD) anode under near-neutral conditions.
View Article and Find Full Text PDFHumans can easily perform various types of hugs in human contact and affection experience. With the prevalence of robots in social applications, they would be expected to possess the capability of hugs as humans do. However, it is still not an easy task for robots, considering the complex force and spatial constraints of robot hugs.
View Article and Find Full Text PDFA fluorosulfate ion (FSO) is a hydrolysis product of sulfuryl fluoride (SOF), which is widely used to fumigate buildings, soil, construction materials, and postharvest commodities, and is a potent greenhouse gas. It is a potential marker for biological exposure to SOF and for monitoring the progress of reactions used to scrub SOF from fumigation vent gases. Here, we report a simple and inexpensive potentiometric method for determining FSO using a commercial nitrate-selective electrode and discuss its application.
View Article and Find Full Text PDFThe demand for milk has increased globally, accompanied by an increase in waste milk. Here, we provide an artificial humification technology to recycle waste milk into an agricultural nano-fertilizer. We use KOH-activated persulfate to convert waste milk into fulvic-like acid and humic-like acid.
View Article and Find Full Text PDFDue to the frequent occurrence of piracy incidents, normal trade, and transportation activities have been hindered. This paper uses the Piracy and Armed Robbery dataset in the Global Integrated Shipping Information System to analyze the types and evolutionary characteristics of shipping risk caused by piracy and the piracy behavior patterns in different seas. This study found that there are three regions with high incidence of piracy in the world, and their gathering centers change dynamically over time.
View Article and Find Full Text PDFTo reduce the structural deterioration of mass concrete structures from temperature cracks, and lower energy consumption caused by the traditional mass concrete hydration heat cooling process, this paper reports the preparation of concrete temperature-controlled phase change aggregate (PCA) by a vacuum compaction method using light and high-strength black ceramite and No. 58 fully refined paraffin wax as phase change material (PCM), and the encapsulation technology of the aggregate by using superfine cement and epoxy resin. Further, through laboratory tests, the cylinder compressive strength, thermal stability and mixing breakage rate of the encapsulated PCA were tested, and the differences in mechanical properties such as compressive strength, flexural strength and splitting tensile strength between phase change aggregate concrete (PCAC) and ordinary concrete were studied.
View Article and Find Full Text PDFPeracetic acid (PAA) may be used in drinking water treatment for pre-oxidation and mussel control at the intake. PAA may exert a downstream chlorine demand, but full details of this reaction have not been reported. There are three possible mechanisms of this demand: (1) PAA may react directly with chlorine; (2) PAA exists in equilibrium with hydrogen peroxide, which is known to react with chlorine; and (3) as HO reacts with chlorine, PAA will hydrolyze to form more HO to re-establish PAA/HO equilibrium, thereby serving as an indirect reservoir of chlorine demand.
View Article and Find Full Text PDFInteraction of antibiotics with metal ions in aquatic environments, commonly occurring to form complexes, may affect the migration, transformation and reactivity of residual antibiotics. This study demonstrates the photolysis of Fe(III) by UV irradiation at pH 3.5, as an advanced oxidation process, to produce •OH for the abatement of a common broad-spectrum antibiotic compound, tetracycline (TET).
View Article and Find Full Text PDFUV/Cl and UV/HO are advanced oxidation processes (AOPs) used for drinking water treatment and water reuse. This work explored the hypothesis that UV/Cl becomes more competitive to UV/HO at neutral-to-high pH as the concentration of total organic carbon (TOC) increases. Lab experiments and kinetic modelling were used to compare initial pseudo first-order contaminant decay rate coefficients between the AOPs at various pH and TOC conditions.
View Article and Find Full Text PDFNerve guidance conduits (NGCs) have become a promising alternative for peripheral nerve regeneration; however, the outcome of nerve regeneration and functional recovery is greatly affected by the physical, chemical, and electrical properties of NGCs. In this study, a conductive multiscale filled NGC (MF-NGC) consisting of electrospun poly(lactide-co-caprolactone) (PCL)/collagen nanofibers as the sheath, reduced graphene oxide /PCL microfibers as the backbone, and PCL microfibers as the internal structure for peripheral nerve regeneration is developed. The printed MF-NGCs presented good permeability, mechanical stability, and electrical conductivity, which further promoted the elongation and growth of Schwann cells and neurite outgrowth of PC12 neuronal cells.
View Article and Find Full Text PDFThree-dimensional (3D) bioprinting offers a potentially powerful new approach to reverse engineering human pathophysiology to address the problem of developing more biomimetic experimental systems. Human tissues and organs are multiscale and multi-material structures. The greatest challenge for organ printing is the complexity of the structural elements, from the shape of the macroscopic structure to the details of the nanostructure.
View Article and Find Full Text PDFAs a major extracellular matrix component within the skin, collagen has been widely used to engineer human skin tissues. However, most collagen is extracted from animals. Here, we introduced recombinant human type III collagen (rhCol3) as a bioactive component to formulate bioinks for the bioprinting of a full-thickness human skin equivalent.
View Article and Find Full Text PDFPurpose: The purpose of this study was to use the neural network to distinguish optic edema (ODE), and optic atrophy from normal fundus images and try to use visualization to explain the artificial intelligence methods.
Methods: Three hundred and sixty-seven images of ODE, 206 images of optic atrophy, and 231 images of normal fundus were used, which were provided by two hospitals. A set of image preprocessing and data enhancement methods were created and a variety of different neural network models, such as VGG16, VGG19, Inception V3, and 50-layer Deep Residual Learning (ResNet50) were used.
Intimal hyperplasia and restenosis caused by excessive proliferation of smooth muscle cells (SMC) are the main factors for the failure of stent implantation. Drug-eluting stents carried with antiproliferative drugs have emerged as a successful approach to alleviate early neointimal development. However, these agents have been reported to have an undesirable effect on re-endothelialization.
View Article and Find Full Text PDFThe binding between dissolved organic matter (DOM) and micro-pollutants (MPs) results in significant impacts on their migration, transformation and degradation. However, the role of the DOM/MP binding on their oxidative transformation remains poorly studied. The binding of MPs by DOM, in combination with DOM's roles as a photosensitizer and/or a competitor for free radicals, needs to be considered in the context of understanding the DOM's impacts on the oxidative degradation of MPs.
View Article and Find Full Text PDFThe study presented a Monte Carlo simulation of light transport in eight commonly used filtered facepiece respirators (FFRs) to assess the efficacy of UV at 254 nm for the inactivation of SARS-CoV-2. The results showed different fluence rates across the thickness of the eight different FFRs, implying that some FFR models may be more treatable than others, with the following order being (from most to least treatable): models 1512, 9105s, 1805, 9210, 1870+, 8210, 8110s and 1860, for single side illumination. The model predictions did not coincide well with some previously reported experimental data on virus inactivation when applied to FFR surfaces.
View Article and Find Full Text PDFCell alignment plays an essential role in cytoskeleton reorganization, extracellular matrix remodeling, and biomechanical properties regulation of tissues such as vascular tissues, cardiac muscles, and tendons. Based on the natural-oriented features of cells in native tissues, various biomimetic scaffolds have been reported with the introduction of well-arranged ultrafine fibers to induce cell alignment. However, it is still a challenge to fabricate scaffolds with suitable mechanical properties, biomimetic microenvironment, and ability to promote cell alignment.
View Article and Find Full Text PDFExtrusion bioprinting has been widely used to extrude continuous filaments of bioink (or the mixture of biomaterial and living cells), layer-by-layer, to build three-dimensional constructs for biomedical applications. In extrusion bioprinting, printability is an important parameter used to measure the difference between the designed construct and the one actually printed. This difference could be caused by the extrudability of printed bioink and/or the structural formability and stability of printed constructs.
View Article and Find Full Text PDFReindeer () have lengthy seasonal migrations on land and their feet possess excellent locomotor characteristics that can adapt to complex terrains. In this study, the kinematics and vertical ground reaction force (GRF) of reindeer forelimb joints (interphalangeal joint , metacarpophalangeal joint , and wrist joint ) under walk, trot 1, and trot 2 were measured using a motion tracking system and Footscan pressure plates. Significant differences among different locomotor activities were observed in the joint angles, but not in changes of the joint angles ( , , ) during the stance phase.
View Article and Find Full Text PDFThere is an urgent clinical for small diameter vascular grafts (SDVGs) for use in the treatment of coronary artery disease. Moreover, biodegradable SDVGs are drawing increasing attention because they have the potential to restore vascular function with the degradation of vascular graft and tissue regeneration. In this study, we designed triple-layered SDVGs to mimic the native arterial structure, with each layer contributing its unique porosity to the porous structure.
View Article and Find Full Text PDFThis study presents numerical simulations of UVC light propagation through seven different filtered face respirators (FFR) to determine their suitability for Ultraviolet germicidal inactivation (UVGI). UV propagation was modeled using the FullMonte program for two external light illuminations. The optical properties of the dominant three layers were determined using the inverse adding doubling method.
View Article and Find Full Text PDFDespite progress in engineering both vascularized tissues and oriented tissues, the fabrication of 3D vascularized oriented tissues remains a challenge due to an inability to successfully integrate vascular and anisotropic structures that can support mass transfer and guide cell alignment, respectively. More importantly, there is a lack of an effective approach to guiding the scaffold design bearing both structural features. Here, an approach is presented to optimize the bifurcated channels within an anisotropic scaffold based on oxygen transport simulation and biological experiments.
View Article and Find Full Text PDFDegradation kinetics, by-products identification and pathways of a model naphthenic acid, cyclohexanecarboxylic acid (CHA), by the UV/Chlorine process were investigated in this study. Mathematical modeling indicated that the initial CHA decay rate increased rapidly with the chlorine dose when the chlorine dose was lower than 45 mg/L and decreased with further chlorine dose increases. Increasing the chlorine dose from 400 to 800 mg/L resulted in a steady increase in the total removal of CHA after 60 min of UV photolysis.
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