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In this work, a metal–organic framework MIL-68(In)–NH2 incorporated high internal phase emulsion polymeric monolith (MIL-68(In)–NH2/polyHIPE) was prepared and applied as a solid phase extraction adsorbent for the extraction and detection of trace triazine herbicides in environmental water samples by coupling with HPLC-UV detection. The fabricated material showed good adsorption for simazine, prometryn, and prometon in water samples because of π–π interactions and hydrogen bonding interactions. Under optimal conditions, the maximum adsorption capacity of simazine, prometon and prometryn was 800 μg g−1, 800 μg g−1 and 6.01 mg g−1, respectively. The linearities were 10–800 ng mL−1 for simazine, prometon and prometryn. The limits of detection were 31–97 ng L−1, and the recoveries were 85.6–118.2% at four spiked levels with relative standard deviations lower than 5.0%. The method has a high sensitivity for the determination of three triazine herbicides in environmental water samples.

By sacrificing a porous anodic aluminum oxide (AAO) membrane as a template, hollow tubular TpBD (H-TpBD) covalent organic framework (COF) tubes were synthesized in situ and zeolitic imidazolate framework (ZIF-8) nanoparticles were creatively synthesized in situ in H-TpBD tubes at room temperature. H-TpBD COF tubes and ZIF-8/H-TpBD COF tubes were procured by using a strong base or acid to remove the AAO membrane. Then they were analyzed by X-ray diffraction, Fourier infrared spectroscopy, scanning electron microscope, transmission electron microscope, etc. Surprisingly, the obtained TpBD COF has a very small aperture (1.8 nm), thinner tube thickness (50 nm), high stability, and a smooth and homogeneous surface. And the pod-like ZIF-8/H-TpBD COF with complete tubular structure was also obtained.

Many oil adsorption materials are composed of nonrenewable raw materials, and their disposal can increase resource consumption and cause new environmental pollution. In this paper, the carbonized Eichhornia crassipes (CEC) were immobilized with Fe3O4 magnetic nanoparticles and modified with 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane (PFOS) to prepare an oil adsorption material, referred to here as CEC/Fe3O4/PFOS. The magnetic and mechanical strength of the CEC was enhanced by adding Fe3O4 magnetic particles, which enable it efficient to dispose the oil/water solution. CEC/Fe3O4/PFOS shows high porosity (83.53%), low skeletal density (0.487 g/cm3), excellent magnetism, ultrahigh oil absorption capacity (49.94–140.90 g/g), hydrophobic performances with a water contact angle of 150.1 ± 2.3°, and a sliding angle of 10.5°. It is worth noting that the material can be recycled, and the absorbed oil is obtained by distillation. Therefore, this work may provide a candidate for solving the problem of oil pollution using E. crassipes.

Microalgae are primary producers with multiple nutrients in aquatic environments and mostly have applications in biological feed and fuel industry. There are few studies assessing the angiotensin-I-converting enzyme (ACE) inhibition potential of Isochrysis zhanjiangensis, other than its antioxidant potential. In this study, we evaluated a peptide from I. zhanjiangensis (PIZ, FEIHCC) and its vascular endothelial factors and mechanism in human umbilical vein endothelial cells (HUVEC). The results reveal that PIZ (IC50 = 61.38 μM) acts against ACE in a non-competitive binding mode. In addition, PIZ inhibits angiotensin II (Ang II)-induced vascular factor secretion and expression by blocking inflammation and apoptosis through nuclear factor κB (NF-κB), nuclear erythroid 2-related factor 2 (Nrf2), mitogen-activated protein kinases (MAPKs), and the serine/threonine kinase (Akt) signal pathways. This study reveals that PIZ has potential to be developed as a therapeutic agent for hypertension and provides a new method of high-value utilization of I. zhanjiangensis.

ZnO nanoparticles (ZnONPs) are synthesized and incorporated into soybean protein isolate (SPI) to obtain SPI/ZnONPs (SZ) films, and the morphology, size distribution, and stability are determined. The effects of different contents of ZnONPs in the SZ films on the oxygen barrier, antibacterial activity, and thermal and mechanical properties are evaluated. A ZnONPs content of 0.2% in the SZ films improves the tensile strength and microbial inhibition by 231% and 16%, respectively. The thermal stability and oxygen barrier properties of the SZ films are also enhanced with addition of ZnONPs. The ZnONPs dispersed uniformly in the SPI film enhance the interactions between SPI molecules via hydrogen bonding, and the results suggest potential application of ZnONPs in food packaging.

The enrichment of various pollutants in mangrove has attracted widespread attention. Especially, microplastics accumulation in mangrove may provide a more challenging ecological colonization site by enriching pollutants, thus affecting the change of microplastics antibiotic resistance and increasing the risk of antibiotic failure. Herein, the antibiotic-resistant of microplastics and sediment from mangrove were investigated. The results show that isolates are mainly colonized by Vibrio parahemolyticus (V. parahemolyticus), Vibrio alginolyticus (V. alginolyticus), and Shewanella. 100% mangrove microplastics isolates are resistant to chloramphenicol, cefazolin, and tetracycline, especially amoxicillin clavulanate and ampicillin. Meanwhile, the multiple antibiotics resistance (MAR) indexes of V. parahaemolyticus, Shewanella, and V. alginolyticus in mangrove microplastics are 0.72, 0.77, and 0.77, respectively, which are far higher than the MAR index standard (0.2) and that of mangrove sediment isolates. Furthermore, compared with V. parahaemolyticus isolated from the same mangrove microplastics, Shewanella and V. alginolyticus show stronger drug resistance. It should be noted that there is a closely related relationship between the type of microplastics and the antibiotics resistance of isolated bacteria. For the antibiotics sensitivity test of norfloxacin, streptomycin, amoxicillin, and chloramphenicol, V. parahaemolyticus have the lower antibiotics resistance than that of V. alginolyticus isolated from the same mangrove microplastics. However, Vibrio isolated from PE has stronger antibiotics resistance. Results reveal that mangrove may be one of the potential risks for emergence and spread of bacterial antibiotics-resistant and multidrug-resistant, and microplastic biofilms may act as promoters of bacterial antibiotic resistance.

In this paper, based on the principle of superposition of acting forces, we propose a mathematical model for injected fluid-induced stress and calculate the stress distribution and SRV width vs. the stress difference in the formation. The results show that the nature of the propagation of the fracture network in multi-staged hydraulic fracturing depends on the stress in the initial cycle. The larger the horizontal stress difference, the larger the width of the fracture network in the rock. If the stress difference is greater than 5 MPa, the width of the fracture network decreases dramatically. When the net pressure is greater than 8 MPa, the width slowly increases. The calculation results are in good agreement with microseismic monitoring data for conditions in the Southwest shale field (China), suggesting that the proposed model is sufficiently reliable and accurate.

A mussel-inspired new interfacial ionic rectification device is fabricated using porous anodic alumina nanochannels and graphene oxide via dopamine polymerization. In addition, the rectification mechanism is elucidated based on the principles of physics and thermodynamics via finite element simulation and the results show that the interface distance and surface charge play a vital role in ion transport.

A sensitive and intuitive freshness intelligent label was fabricated for indicating the freshness of fish based on porous anodic aluminum (PAA) membrane and bromocresol green. This label is fabricated by the bromocresol green (BCG) immobilized on PAA membrane, which responds through visible color change to the total volatile basic nitrogen (TVBN) released during fish spoilage period. The result showed that the fish is inedible when it was stored at 25 °C for 6 h (TVBN > 20 mg/100 g). Under this condition, the color of BCG/PAA label changed from yellow to green obviously. In addition, BCG/PAA membrane label and the electrospinning nanofiber label were used to evaluate the fish freshness. As a result, the color of BCG/PAA membrane label is more obvious and sensitive. Thus, BCG/PAA membrane label can be considered as a new promising method for the assessment of fish freshness.

Novel viscoelastic self-diverting acid (VDA) systems with and without cosurfactant (sodium dodecylbenzenesulfonate, SDBS) added to enhance reaction retardation and to improve the conventional VDA system are studied. The novel system viscosifies at a pH of ~0.6 and attains a viscosity of ~500 mPa·s. The system without added SDBS viscosifies at a pH of ~2.2 and reaches a final viscosity of 403 mPa·s. Studies of the limestone—acid reaction kinetics showed that the reaction rate fell from 1.37·10–4 mol/(cm2·s) for 20 wt. % HCl solution to 13.2·10–6 and 6.5·10–6 mol/(cm2·s) for VDA solutions without and with added SDBS, respectively. The reaction rate constants (k) for the negative sample control and VDA systems I and II were 1.0740·10–1 (mol/cm3)(–0.3092)·(cm/s), 5.5221·10–4 (mol/cm3)(0.2822)·(cm/s), and 6.3154·10–5 (mol/cm)(0.5554)·(cm/s), respectively. A dual-core flow test showed that wormholes were produced in both cores for the VDA systems rather than a large single channel in a high-permeability core when 20 wt.% HCl solution is used. Thus, a smaller volume of SDBS is needed for flow formation when VDA solution is added. The studies revealed that the novel VDA system retards reaction considerably, improves acid diversion, and has tremendous potential for field applications.

A novel low temperature chitosan hydrogel (

Abalone (Haliotis discus hannai) is a precious seafood in the market. It has been reported that biological active substances derived from abalone have anti-oxidative, anti-inflammatory, anti-bacterial, and anti-thrombosis potential. However, there were few studies to assess whether they have anti-cancer potential. In this study, we evaluated the anti-metastasis and anti-pro-angiogenic factors and mechanism of action of boiled abalone byproduct peptide (BABP, EMDEAQDPSEW) in human fibrosarcoma (HT1080) cells and human umbilical vein endothelial cells (HUVECs). The results demonstrated that BABP treatment significantly lowers migration and the invasion of HT1080 cells and HUVECs. BABP inhibits phorbol 12-myristate 13-acetate (PMA)-induced matrix metalloproteinase (MMP) expression and activity by blocking mitogen-activated protein kinases (MAPKs) and NF-κB signaling and hypoxia-induced vascular endothelial growth factor (VEGF) secretion and hypoxia inducible factor (HIF)-1α accumulation through suppressing the AKT/mTOR signal pathway. BABP treatment inhibits VEGF-induced VEGFR-2 expression and tube formation in HUVECs. The effect of BABP on anti-metastatic and anti-vascular activity in HT1080 cells and HUVECs revealed that BABP may be a potential pharmacophore for tumor therapy in the future.

We propose a mathematical model describing gas flow from a fractured shale reservoir into a horizontal well. Based on Langmuir adsorption theory and Darcy’s law, we have obtained a basic solution using a combination of a point source function, an integral of a Bessel’s function, and the Poisson summation formula. We plotted typical curves for the dimensionless pressure and its derivative on a log-log scale. We analyze the stages of gas flow from the shale formation to the horizontal well and the factors influencing it.

Prodrug, in which the inactive parent drug with good bioavailability is metabolized into an active drug in the body, is one of the main strategies to target the disease site to improve the drug efficiency and reduce the adverse effects of chemotherapy. Because of the good capability of chemical modification, zein, a plant derived protein, and drugs can be conjugated through environmentally sensitive links to form prodrugs capable of triggered drug release. In this study, a novel prodrug was synthesized using paclitaxel (PTX), zein, and a disulfide linker, and nanoparticles were formed by self-assembly of the prodrug. An effective in vitro triggered release, 80-90% in 5 min, of the prodrug based nanoparticles (zein-S-S-PTX_NP) was successfully approached. The cytotoxicity of zein-S-S-PTX_NP as well as the zein encapsulation of PTX (zein_PTX_NP) and pure PTX on HeLa cells and NIH/3T3 fibroblast cells was tested using MTS assay. It showed that, after the treatment of zein-S-S-PTX_NP at the equivalent PTX concentrations of 0.1, 0.5, 1, and 5 μg/mL, respectively, zein-S-S-PTX_NP had zero damage to normal cells but a similar cytotoxicity to cancer cells as pure PTX. In the animal study, the tumor was 50% of the original size after the treatment of zein-S-S-PTX_NP for 9 days with 3 doses. This study suggested that the novel prodrug based nanoparticle zein-S-S-PTX_NP could be a promising approach in chemotherapy with targeted delivery, improved efficacy, and reduced side effects.

A new high-efficiency adsorbent (PDA-CaCO3) is fabricated via simple thermal calcination of ostracean shells and chemical modification with dopamine. The adsorption capacity for Pb(II) and Cd(II) was 336.32 and 175.48 mg g−1, respectively. Importantly, it can be easily regenerated by low-cost reagents, and exhibited a high adsorption capacity after multiple adsorption–desorption cycles.

Two carbonyl groups modified XAD-4 resins (XAD-4-I and XAD-4-II) were synthesized by chemically modifying Amberlite XAD-4 with carbon tetrachloride and benzoyl chloride according to the Friedel–Crafts reaction. After the chemical modification, the Brunauer–Emmet–Teller (BET) surface area and pore volume of the resins increased about 50% while their median pore size remained constant. More importantly, the modified resins adsorbed about 20% more phenol from aqueous solutions than the original XAD-4 at 298, 308 and 318 K, respectively; and the modified resins could be used directly in water without pre-wetting. The Freundlich and Sips models fitted the isotherm data better than the Langmuir model. Analysis of isosteric adsorption enthalpy indicated that XAD-4 has a more heterogeneous surface than the modified resins. Adsorption kinetics data suggested that the three resins could reach equilibrium within 1 h, and the pseudo-first-order and pseudo-second-order rate models could describe the kinetic data effectively. At a phenol feed concentration of 574.0 mg/L, the dynamic adsorption capacities of XAD-4, XAD-4-I and XAD-4-II were measured to be 80.6, 94.8 and 93.6 mg/g, respectively. Desorption experiments showed that the used resins could be regenerated completely by a 50% (v/v) ethanol aqueous solution.

Novel chiral dimeric salen Mn(III) complexes bridged with N,N-dialkylimidazolium ionic liquids (ILs) at the C-5 position of the salicylaldehyde moieties were designed and synthesized. The ILs-bridged complexes presented excellent enantioselectivity and catalytic activity in the oxidative kinetic resolution of α-methyl benzyl alcohol, using diacetoxyiodobenzene as oxidant. The complexes combined the high catalytic efficiency of the active centers and the special solubility of the ILs, thus exhibiting notable efficacy of oxidative kinetic resolution and facile recovery from the reaction system by changing the solvent.

Chiral oxovanadium (IV) Schiff base complex covalently grafted with ionic liquid (IL: 1-(3-aminopropyl)-3-methylimidazolium tetrafluoroborate) has been reported first time. The IL-functionalized complex was found to be an efficient catalyst in the enantioselective oxidation of methyl aryl sulfides to sulfoxides with hydrogen peroxide as an oxidant. Especially, the IL-functionalized complex could be recovered conveniently by simple precipitation with addition of hexane and reused at least six cycles without loss of activity and enantioselectivity.

Cu/Cu2O nanowires were synthesized using anodic aluminum oxide templates in an aqueous acidic electrolyte using alternating current electrochemical deposition. The features of the final product were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (SEM). The results indicated that the diameter of the nanowires is about 50 nm, which is in accord with the size of the pores in the anodic aluminum oxide templates. The crystalline structure of the Cu and Cu2O nanowires exhibit preferred orientations of Cu (111) and Cu2O (200), respectively. The experimental results showed that contents of Cu and Cu2O in the final product are controlled by changing the pH value of the electrolyte. Pure Cu nanowires were obtained at lower pH values of 1–3, while pure Cu2O nanowires formed at a higher pH value of 5. When the pH = 4, the nanowires produced were a composite of Cu and Cu2O. The growth of Cu2O nanowires in acidic electrolyte is ascribed to a local increase in pH at the base of the pores in the template and a phenomenological model for this process is proposed and discussed.

Alumina nanostructures, nanowires, and semicolumn nanotubes with high aspect ratios were synthesized by the chemical etching of porous alumina membranes (PAMs) in phosphoric acid solution. The morphology and structure of alumina nanostructures were analyzed by scanning electron microscopy (SEM), energy dispersive spectrum (EDS), and X-ray diffraction (XRD), respectively. The results showed that the typical features of highly flexible nanostructures were around 20-40 nm in diameter and around 100 microm in length. EDS analysis indicated that the nanostructures were constructed by aluminum oxide. The crystalline structure of the alumina nanostructures was amorphous, which was in accordance with that of the PAMs. Furthermore, the morphology of the PAMs was characterized in detail by atomic force microscope (AFM) and SEM. On the basis of AFM and SEM observations, a possible formation mechanism of alumina nanostructures was discussed, and the inhomogeneous dissolution between the triple points and the side walls was considered to be the essential factor deciding the formation of nanostructures.

The bottom-hole pressure response which can reflect the gas flow characteristics is important to study. A mathematical model for description of gas from porous coalbed methane (CBM) reservoirs with complex boundary conditions flowing into horizontal wells has been developed. Meanwhile, basic solution of boundary elements has been acquired by combination of Lord Kelvin point source solution, the integral of Bessel function, and Poisson superimpose formula for CBM horizontal wells with complex boundary conditions. Using this model, type curves of dimensionless pressure and pressure derivative are obtained, and flow characteristics of horizontal wells in complex boundary reservoirs and relevant factors are accordingly analyzed.

Triple-porosity model is usually adopted to describe reservoirs with multiscaled pore spaces, including matrix pores, natural fractures, and vugs. Multiple fractures created by hydraulic fracturing can effectively improve the connectivity between existing natural fractures and thus increase well deliverability. However, little work has been done on pressure transient behavior of multistage fractured horizontal wells in triple-porosity reservoirs. Based on source/sink function method, this paper presents a triple-porosity model to investigate the transient pressure dynamics and flux distribution for multistage fractured horizontal wells in fractured-vuggy reservoirs with consideration of stress-dependent natural fracture permeability. The model is semianalytically solved by discretizing hydraulic fractures and Pedrosa’s transformation, perturbation theory, and integration transformation method. Type curves of transient pressure dynamics are generated, and flux distribution among hydraulic fractures for a fractured horizontal well with constant production rate is also discussed. Parametric study shows that major influential parameters on transient pressure responses are parameters pertinent to reservoir properties, interporosity mass transfer, and hydraulic fractures. Analysis of flux distribution indicates that flux density gradually increases from the horizontal wellbore to fracture tips, and the flux contribution of outermost fractures is higher than that of inner fractures. The model can also be extended to optimize hydraulic fracture parameters.

Mesoporous Si-C-O fibers were fabricated by air activation of a kind of carbon-rich SiC-C fibers at 600 degrees C. The SiC-C fibers were prepared from the hybrid precursor of polycarbosilane and pitch through melt-spinning, air curing and pyrolysis in nitrogen. The carbon content of the SiC-C fibers was 54.4 wt%, and decreased to lower than 25 wt% after activation for more than 5 hours. Meanwhile, the surface area increased up to 260 m2/g, with a narrow mesopore size distribution mainly in the range of 2-5 nm. The SiC-phase derived from the polycarbosilane and the C-phase derived from the pitch form a bicontinuous interpenetrating network, which plays an important role for the narrow pore size distribution.

CNx/C nanotube arrays were fabricated via a simple chemical modification porous alumina membrane in situ method. The nanotubes consist of two sections featuring straight and hollow cylinder structure, one section made of N-doped carbon and the other one made of pure carbon. The metal–semiconductor junction was formed in the middle as a result of being doped or undoped with nitrogen. The on–off current ratio at ±5 V is 25. The applicability of chemical modification in situ technique provides us with a good opportunity for practical use of the multiwall nanotube for future nano-devices.

Ordered Ni/Al2O3 core–shell nanowire arrays were prepared in porous alumina membrane via alternating current electrodeposition and chemical etching methods. The shape of the inner Ni core is column...