Ion sieving in graphene oxide membranes via cationic control of interlayer spacing.

Graphene oxide membranes-partially oxidized, stacked sheets of graphene-can provide ultrathin, high-flux and energy-efficient membranes for precise ionic and molecular sieving in aqueous solution. These materials have shown potential in a variety of applications, including water desalination and purification, gas and ion separation, biosensors, proton conductors, lithium-based batteries and super-capacitors. Unlike the pores of carbon nanotube membranes, which have fixed sizes, the pores of graphene oxide membranes-that is, the interlayer spacing between graphene oxide sheets (a sheet is a single flake inside the membrane)-are of variable size. Furthermore, it is difficult to reduce the interlayer spacing sufficiently to exclude small ions and to maintain this spacing against the tendency of graphene oxide membranes to swell when immersed in aqueous solution. These challenges hinder the potential ion filtration applications of graphene oxide membranes. Here we demonstrate cationic control of the interlayer spacing of graphene oxide membranes with ångström precision using K+, Na+, Ca2+, Li+ or Mg2+ ions. Moreover, membrane spacings controlled by one type of cation can efficiently and selectively exclude other cations that have larger hydrated volumes. First-principles calculations and ultraviolet absorption spectroscopy reveal that the location of the most stable cation adsorption is where oxide groups and aromatic rings coexist. Previous density functional theory computations show that other cations (Fe2+, Co2+, Cu2+, Cd2+, Cr2+ and Pb2+) should have a much stronger cation-π interaction with the graphene sheet than Na+ has, suggesting that other ions could be used to produce a wider range of interlayer spacings.

Development and Internal Validation of a Prediction Model for Difficult Laryngoscopy Using Ultrasound-Derived Factor in Comatose Patients.

OBJECTIVES: The distance from skin to the hyoid bone (DSHB) and skin to the anterior commissure of vocal cords (DSAC) are reliable parameters for pre-operative airway ultrasound assessment in awake patients and can be assessed in comatose patients. This study aimed to inspect its feasibility and accuracy in predicting difficult laryngoscopy for comatose patients. METHODS: A prospective cohort study included patients with a Glasgow Coma Scale (GCS) of ≤8 who underwent emergency tracheal intubation between November 2019 and August 2020. The outcome was difficult laryngoscopy and classified according to the Cormack-Lehane grading. RESULTS: A total of 151 patients were included in the study. Fifty-two (34.4%) patients were categorized as having difficult laryngoscopy. The DSHB add DSAC (hereinafter referred to as the "DSBAC") was superior to either parameter alone in the predictive performance, and the optimal cut-off value was 1.90. To optimize the predictive value, DSBAC (adjusted odds ratio [OR]: 7.76; 95% confidence interval [CI]: 2.88-20.94; P < .001), GCS (adjusted OR: 1.39; 95% CI: 3.93-26.28; P = .039), mandibular retraction (adjusted OR: 8.20; 95% CI: 1.92-35.09; P = .005) and edentulous (adjusted OR: 4.23; 95% CI: 1.40-12.80; P = .011) were included in a multivariable model and constructed a nomogram. Discrimination and calibration statistics were satisfactory, with C-index above 0.80 from both model development and internal validation. CONCLUSIONS: Ultrasound-derived factor, DSBAC, can be easily assessed and help predict difficult laryngoscopy among comatose patients. A simple nomogram including only four clinical items exhibited excellent discrimination performance and was useful when comatose patients underwent emergency tracheal intubation.

COVID-19 and Acute Cardiac Injury: Clinical Manifestations, Biomarkers, Mechanisms, Diagnosis, and Treatment.

PURPOSE OF REVIEW: This review aims to comprehensively explore the clinical characteristics of COVID-19-related cardiac injury and examine the potential mechanisms underlying cardiac injury in patients affected by COVID-19. RECENT FINDINGS: The COVID-19 pandemic has primarily been associated with severe respiratory symptoms. However, emerging evidence has indicated that a significant number of COVID-19 patients also experience myocardial injury, leading to conditions such as acute myocarditis, heart failure, acute coronary syndrome, and arrhythmias. The incidence of myocardial injury is notably higher in patients with preexisting cardiovascular diseases. Myocardial injury often manifests with elevated levels of inflammation biomarkers, as well as abnormalities observed on electrocardiograms and echocardiograms. COVID-19 infection has been found to be associated with myocardial injury, which can be attributed to several pathophysiological mechanisms. These mechanisms include injury caused by hypoxia, resulting from respiratory compromise, a systemic inflammatory response triggered by the infection, and direct attack on the myocardium by the virus itself. Furthermore, the angiotensin-converting enzyme 2 (ACE2) receptor plays a crucial role in this process. Early recognition, prompt diagnosis, and a comprehensive understanding of the underlying mechanisms are essential for effectively managing and reducing the mortality associated with myocardial injury in COVID-19 patients.

Urban growth boundaries optimization under low-carbon development: Combining multi-objective programming and patch cellular automata models.

Urban Growth Boundaries (UGBs) are a tool to control urban sprawl. However, the way to optimize future urban land uses and fix their boundaries is not clear. This paper presents a new framework to delimit UGBs while accounting for ecological, economic, and carbon storage benefits. Aggregate land-use constraints are included in a multi-objective optimization algorithm to capture non-inferior solutions on the Pareto Surface (PS) under different objective scenarios. A patch-level cellular automata simulation model is then used to spatially allocate these land uses, followed by a new two-step adjustment method to delineate the UGBs. This modeling is applied to Wuhan, China. The results show that: (1) One district (Caidian) will have a strong economic growth under low-carbon development. (2) The maximization of carbon storage reduces losses in ecological benefits, suggesting that carbon storage be considered in urban growth planning. (3) The combined model framework and two-step boundary adjustment method can help urban planners define different UGB scenarios and make science-based policy decisions.

The predictive effect of direct-indirect bilirubin ratio on clinical events in acute coronary syndrome: results from an observational cohort study in north China.

BACKGROUND: Patients with extremely high-risk ASCVD usually suffered poor prognosis, bilirubin is considered closely related to cardiovascular outcomes. However, there is controversy over the relationship between bilirubin and coronary artery disease. This study aimed to evaluate the predictive value of the DIBIL ratio in patients with extremely high-risk ASCVD. METHODS: 10,260 consecutive patients with extremely high-risk ASCVD were enrolled in this study. All patients were divided into three groups according to their DIBIL ratio. The incidence of MACCEs was recorded, and in a competing risk regression, the incidence of MACCEs and their subgroups were recorded. The direct-indirect bilirubin ratio (DIBIL ratio) was calculated by the direct bilirubin (umol/L)/indirect bilirubin (umol/L) ratio, all laboratory values were obtained from the first fasting blood samples during hospitalization. RESULTS: The area under the ROC curve of the DIBIL ratio to predict the occurrence of all-cause death was 0.668, the cut-off value of which is 0.275. Competing risk regression indicated that DIBIL ratio was positively correlated with all-cause death [1.829 (1.405-2.381), p < 0.001], CV death [1.600 (1.103, 2.321), p = 0.013]. The addition of DIBIL ratio to a baseline risk model had an incremental effect on the predictive value for all-cause death [IDI 0.004(0, 0.010), p < 0.001; C-index 0.805(0.783-0.827), p < 0.001]. CONCLUSION: The DIBIL ratio was an excellent tool to predict poor prognosis, suggesting that this index may be developed as a biomarker for risk stratification and prognosis in extremely ASCVD patients.

Evaluation of Sampson equation for LDL-C in acute coronary syndrome patients: a Chinese population-based cohort study.

OBJECTIVE: Low-density lipoprotein cholesterol (LDL-C) is an important cardiovascular disease marker that is used to estimate the risk of acute coronary syndrome in patients. The Sampson equation is an accurate LDL-C equation, but its application in Chinese patients is unclear. METHODS: This study enrolled 12,989 consecutive Chinese patients with the acute coronary syndrome (ACS), LDL-C levels were determined by direct standard method and two indirect equations (Friedewald and Sampson). The detection accuracy and consistency of these two equations were compared in patients classified by triglyceride (TG). In addition, the efficiency of the Sampson equation was also evaluated in patients with different comorbidities. RESULTS: Patients were divided into six groups according to TG level, and indicated that the Sampson formula was more accurate than the Friedewald formula in all TG spectrums (P < 0.001). The Friedewald formula may underestimate the risk in patients with TG > 400 mg/dL, especially in TG > 800 mg/dL group (r: 0.931 vs. 0.948, 0.666 vs. 0.898, respectively). Compared with the Friedewald equation, the Sampson equation showed more advantages in female, age ≥ 65, body index mass (BMI) < 25, non-smoker, and non-diabetes (0.954 vs. 0.937, 0.956 vs. 0.934, 0.951 vs. 0.939, 0.951 vs. 0.936, and 0.947 vs. 0.938, respectively) than those in male, age < 65, BMI ≥ 25, smoker, and diabetes. CONCLUSIONS: Compared with the Friedewald equation, the Sampson equation is more accurate for LDL-C evaluation in Chinese patients diagnosed with ACS, especially in patients with hypertriglyceridemia even in those with TG > 800 mg/dL. Additionally, the Sampson equation demonstrates greater accuracy even in subgroups of various baseline characteristics and comorbidities.

Effect of family history of atrial fibrillation on recurrence after atrial fibrillation ablation: A report from the Chinese Atrial Fibrillation Registry Study.

BACKGROUND: To evaluate the impact of family history of atrial fibrillation (FAF) on postablation atrial tachyarrhythmia (AT) recurrence. METHODS: All the 8198 patients undergoing initial AF ablation registered in the Chinese Atrial Fibrillation Registry study were analyzed. FAF was defined as having first-degree relatives diagnosed as AF at age 65 years or younger, and before the time the case in this study was diagnosed. Cox proportional hazards models were used to evaluate the impact of FAF on postablation AT recurrence. Age, sex, body mass index, AF type, history of congestive heart failure, hypertension, diabetes mellitus, prior stroke/transient ischemic attack/systemic embolism, vascular diseases, use of contact force-sensing catheter, and completion of high school were adjusted. The definition of AT recurrence was any documented AF, atrial flutter, or AT lasting more than or equal to 30 s after 3 months blanking period. RESULTS: After a mean follow-up of 26.2 ± 19.6 months, 318 out of the 645 patients (49.3%) with FAF and 3339 out of the 7553 patients (44.2%) without FAF experienced AT recurrence, corresponding to annual recurrence rates of 22.8% and 20.2%, respectively. Patients with FAF had a significant higher risk of AT recurrence (adjusted hazard ratio 1.129, 95% confidence interval 1.005-1.267) in multivariable analysis. Moreover, FAF had a significant higher impact on AT recurrence in the subgroup of patients diagnosed with AF at age 50 years or younger (p for interaction = .036). CONCLUSION: FAF is a risk factor for postablation AT recurrence. This is especially true in those with AF diagnosed at 50 years or younger.

The synthesis of 3D graphene/Au composites via γ-ray irradiation and their use for catalytic reduction of 4-nitrophenol.

Graphene oxide (GO) and gold ions (Au3+) can be simultaneously reduced and self-assembled into a three-dimensional (3D) graphene/Au composite (GA/Au) porous structure at room temperature via one-step γ-ray irradiation. The microstructure of GA/Au composites were observed under different magnifications and the pores were observed to be uniform 3D porous structure. In addition, Au nanoparticles were homogeneously attached to graphene sheets and had a typical diameter of 6 nm. These GA/Au composites were analyzed and characterized by x-ray diffraction analysis, x-ray photoelectron spectroscopy, and thermal gravity analysis. Due to synergistic catalysis between graphene and Au nanoparticles, GA/Au composites catalyzed 4-nitrophenol with excellent catalytic performance, even at concentrations up to 6.48 × 10-3 M. When the concentration of 4-nitrophenol was 2.16 × 10-3 M and 4.22 × 10-3 M, the first-order kinetic constants were 2.00 and 1.43 min-1, respectively.

Left-sided accessory pathways successfully ablated from the aortomitral continuity region: distinctive atrial activation patterns and anatomic concerns.

AIMS: Accessory pathways (APs) successfully ablated at the aortomitral continuity (AMC) were sporadically reported but relevant data are very limited. We aimed to describe the electrophysiological characteristics of AMC-AP and the related anatomy. METHODS AND RESULTS: This study involved eight (male/female = 3/5, mean age 42.6 ± 10.5 years) patients with left-sided AP successfully ablated in the AMC region. The retrograde atrial activation sequence was analysed and compared via recordings at the His-bundle (HB), coronary sinus (CS), and roving catheter during tachycardia, and the peak of QRS from the same cardiac circle used as time reference. Of the eight patients, two received prior ablations. During tachycardia, the activation time at the proximal CS (CSp), lateral CS (CSl), and HB region averaged 120 ± 26 ms, 124 ± 29 ms, and 117 ± 21 ms following the reference, respectively (P = 0.86). The latest atrial activation was recorded in the posterior CS which averaged 135 ± 25 ms following the reference. Placing the ablation catheter to AMC via retrograde approach was attempted in all cases but stable positioning achieved in none. Via transseptal approach, the ablation catheter could be easily placed at the AMC and recorded the earliest retrograde atrial activations with 60 ± 27 ms earlier than the relatively 'earliest' CS/HB recordings, and ablation at this site successfully eliminated AP conduction. No patients had recovered AP conduction after at least 12-month follow-up. CONCLUSION: AMC-AP is featured by recording comparable retrograde atrial activation times at CSp, CSl, and HB with the latest recordings at the posterior CS. Stable placement and successful ablation in the AMC via retrograde aortic approach was difficult but can be achieved via transseptal approach.

Physical activity and atrial tachyarrhythmia recurrence in atrial fibrillation patients after catheter ablation.

BACKGROUND: The association between physical activity (PA) and atrial tachyarrhythmia (AT) recurrence after ablation for atrial fibrillation (AF) remains unclear. METHODS: We consecutively enrolled 496 patients treated with AF ablation therapy in Beijing Anzhen Hospital. After excluding six patients with valvular heart disease, seven patients with congenital heart disease, 33 patients lost to follow-up, and 14 patients who did not provide PA level during follow-ups, 436 patients had their PA level assessed by the International Physical Activity Questionnaire-Short Form before ablation and each time of follow-up. The association between PA level (measured at the time closest to AT recurrence, or the end of 12-month follow-up if no AT recurrence), as well as active PA during follow-up, and postablation AT recurrence was tested by multivariate logistic regression. RESULTS: Of the enrolled patients, 134 (30.7%) patients experienced AT recurrence in the first 12 months postablation. Compared to patients with low PA, patients with moderate or high PA had a lower risk of AT recurrence (odds ratio [OR] = .44; 95% confidence interval [CI], .25-.80; P = .01 for patients with moderate PA; and OR = .43 [95% CI, .21-.85], P = .02 for patients with high PA). Compared to patients without active PA, patients with active PA had a lower risk of AT recurrence (OR = .44 [95% CI, .27-.70], P < .01). CONCLUSIONS: Moderate and high PA are associated with a lower risk of AT recurrence after AF ablation. Active PA during follow-up is also associated with a significantly lower risk of AT recurrence in the postablation AF population.

Effectiveness and safety of atrial fibrillation ablation in females.

BACKGROUND: Existing data on the effectiveness and safety of atrial fibrillation (AF) ablation in females are limited to studies of small sample size, lacking longer term follow-up or adjustment for potential confounders. METHODS: A total of 6421 patients (2072 females) undergoing a first AF ablation procedure after enrollment in the Chinese Atrial Fibrillation Registry (China-AF) study between August 2011 and December 2017 were analyzed. We evaluated the effectiveness (recurrence of documented [symptomatic or not] atrial tachyarrhythmia (AT)) and the safety (incidence of procedure-related complications) of AF ablation in female patients compared to male patients. Sensitivity analyses based on routine data were also utilized to avoid potential sex differences in reporting of AF symptoms. RESULTS: Females were about 5 years older than males at the time of ablation (mean age 63.4 ± 9.5 vs 58.3 ± 10.8, P < .0001). A higher proportion of female patients had paroxysmal AF (74.3% vs 56.7%, P < .0001), hypertension (69.7% vs 61.3%, P < .0001), and hyperlipidemia (57.2% vs 52.9%, P = .001). Female sex was found to be an independent risk factor of AT recurrence in multivariate analyses (HR = 1.26, 95% CI 1.15-1.38, P < .0001). These findings were confirmed in sensitivity analyses using only Holter data. Female sex was also associated with a higher risk of periprocedural complications after adjustment for baseline variables (OR = 1.41, 95% CI 1.03-1.94, P = .03). CONCLUSIONS: Female sex is an independent risk factor of AT recurrence and periprocedural complications after AF ablation.

Reusable fibrous adsorbent prepared via Co-radiation induced graft polymerization for iodine adsorption.

Volatile iodine released from nuclear power plant reactors is radiological hazard to environment and human's health because of their high fission yield and environmental mobility. The complexity of nuclear waste management motivated the development of solid-phase adsorbents. Herein, co-radiation induced graft polymerization (CRIGP) was employed in the graft polymerization of N-vinyl-2-pyrrolidone (NVP) onto polyethylene-coated polypropylene skin-core (PE/PP) fibers using electron beam (EB) irradiation. This work provides a one-step green synthetic approach to prepare iodine fibrous adsorbents without any chemical initiators or large amount of organic solvent. The original and modified PE/PP fibers were characterized by fourier transform infrared spectrometry (FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric (TG) and scanning electron microscopy (SEM) to demonstrate the grafting of NVP onto the PE/PP fibers. The capacity of iodine absorbed by the PE/PP-g-PNVP fibers was 1237.8 mg/g after 180 min. Meanwhile, absorbents can be regenerated efficiently by two different means of ethanol elution and heating at 120 °C, respectively. Within 10 min, 94.17% and 90.12% of the iodine can be released from the PE/PP-g-PNVP fibers with these two methods, respectively. The adsorbent exhibited a long service life of at least ten adsorption-desorption cycles, suggesting that PE/PP-g-PNVP fibers might be a promising adsorbent for volatile iodine adsorption from fission products in nuclear power plant reactors.

Zwitterionic Nanofibrous Membranes with a Superior Antifouling Property for Gravity-Driven Crude Oil-in-Water Emulsion Separation.

The development of membranes with a superior antifouling property and high-permeation flux is extensively considered but still a challenge for handling emulsified oil foulants in wastewater. Herein, a zwitterionic nanohydrogel-grafted  PVDF (ZNG- g-PVDF) nanofibrous membrane was fabricated via a simple surface activation and amide reaction. By tailoring the parameters for electrospinning, PAA-g-PVDF nanofibrous membranes with interpenetrated nanofibers and microsphere structure were formed, and the membrane surface was endowed with high roughness on the micrometer scale. Combined with the strong hydration ability of the grafted zwitterionic nanohydrogels, the obtained ZNG- g-PVDF nanofibrous membrane exhibited a superhydrophilic property and nearly zero adhesion to crude oil under water. It thus showed an extremely high removal efficiency (∼98.7%) for gravity-driven separation of the crude oil-in-water emulsion. Both the water-permeating flux and oil content in the collected filtrate (lower than 13 ppm) showed little change during 10 cycles of the filtration experiment, indicating superior crude oil foulant repellency performance of the ZNG- g-PVDF nanofibrous membrane. Considering the high energy saving of the gravity-driven separation process, this novel ZNG- g-PVDF nanofibrous membrane possesses broad applications in the field of emulsified crude oil foulant cleanup in an aquatic environment.

The SNP Rs915014 in MTHFR Regulated by MiRNA Associates with Atherosclerosis.

BACKGROUND/AIMS: The association between the genetic polymorphisms located in either the exon or untranslated region of MTHFR and the risk of human atherosclerosis has been well-documented. This study analyzed MTHFR polymorphisms at the 3'-untranslated region for association with risk and outcome of atherosclerosis in a Chinese Han population. METHODS: The hospital based case-control study was conducted with 500 patients and 600 healthy volunteers as control enrolled. The genotyping was conducted by using Taqman probe. The potential interaction was predicted by multiple bioinformatics analysis. The relative expression of MTHFR was detected by qRT-PCR. Further confirmation was determined by dual-luciferase assay. The plasma homocysteine levels were assayed by ELISA. RESULTS: Cigarette smoking, alcohol consumption, diabetes, hypertension and low levels of serum high-density lipoprotein-C were associated with an increased risk of developing ischemic stroke. MTHFR rs915014 AG and GG genotypes were significantly associated with increased risk of rs915014 compared with the GG genotype. The qRT-PCR confirmed that MTHFR rs915014 AG or GG genotypes could facilitate miR-2861 binding leading to decreased MTHFR levels in cells. In addition, patients carrying the MTHFR rs915014 AG or GG genotypes were associated with accumulation of circulating tHcy volume and a poor atherosclerosis consequence. CONCLUSIONS: This study demonstrates that the MTHFR rs915014 is associated with increased risk of atherosclerosis and might be a shot term outcome biomarker for atherosclerosis patients.

Tris-amidoximate uranyl complexes via η2 binding mode coordinated in aqueous solution shown by X-ray absorption spectroscopy and density functional theory methods.

The present study sheds some light on the long-standing debate concerning the coordination properties between uranyl ions and the amidoxime ligand, which is a key ingredient for achieving efficient extraction of uranium. Using X-ray absorption fine structure combined with theoretical simulation methods, the binding mode and bonding nature of a uranyl-amidoxime complex in aqueous solution were determined for the first time. The results show that in a highly concentrated amidoxime solution the preferred binding mode between UO22+ and the amidoxime ligand is η2 coordination with tris-amidoximate species. In such a uranyl-amidoximate complex with η2 binding motif, strong covalent interaction and orbital hybridization between U 5f/6d and (N, O) 2p should be responsible for the excellent binding ability of the amidoximate ligand to uranyl. The study was performed directly in aqueous solution to avoid the possible binding mode differences caused by crystallization of a single-crystal sample. This work also is an example of the simultaneous study of local structure and electronic structure in solution systems using combined diagnostic tools.

Durable Anti-Superbug Polymers: Covalent Bonding of Ionic Liquid onto the Polymer Chains.

Here, we fabricated the ionic liquid (IL) grafted poly(vinylidene fluoride) (PVDF) (PVDF-g-IL) via electron-beam irradiation to fight common bacteria and multidrug-resistant "superbugs". Two types of ILs, 1-vinyl-3-butylimmidazolium chloride (IL (Cl)) and 1-vinyl-3-ethylimidazolium tetrafluoroborate (IL (BF4)), were used. It was found that the PVDF-g-IL exhibited superior antibacterial performance, with almost the same mechanical and thermal performance as unmodified PVDF. Nonwovens and films made from PVDF-g-IL materials exhibited broad-spectrum antimicrobial activity against common bacteria and "superbugs" with the strong electrostatic interactions between ILs and microbial cell membranes. With extremely low IL loading (0.05 wt %), the cell reduction of PVDF-g-IL (Cl) nonwovens improved from 0.2 to 4.4 against S. aureus. Moreover, the antibacterial activity of PVDF-g-IL nonwovens was permanent for the covalent bonds between ILs and polymer chains. The work provides a simple strategy to immobilize ionic antibacterial agents onto polymer substrates, which may have great potential applications in healthcare and household applications.

Local Grafting of Ionic Liquid in Poly(vinylidene fluoride) Amorphous Region and the Subsequent Microphase Separation Behavior in Melt.

Polymer-based nanostructures can be generally created by self-assembly of block copolymers that are commonly synthesized by living radical polymerization. In this study, a new strategy is proposed to fabricate block-like copolymers by using the template of binary phase structure of semicrystalline polymers. Poly(vinylidene fluoride) (PVDF) is thermodynamically miscible with an unsaturated ionic liquid (IL) (1-vinyl-3-ethylimidazolium tetrafluoroborate) in the melt and IL molecules are expelled out from the crystalline parts during the crystallization of PVDF. Therefore, the IL molecules are only located at the amorphous region of PVDF crystals. The electron beam irradiation of the IL incorporated PVDF leads to the local grafting of IL molecules onto the PVDF molecular chains in the amorphous region, so block-like grafting polymer chains of crystalline PVDF-b-(amorphous PVDF-g-IL)-b-crystalline PVDF can be achieved. The subsequent heating of the irradiated sample induces the microphase separation of PVDF-g-IL from the ungrafted PVDF chains.

Novel multifunctional nanofibers based on thermoplastic polyurethane and ionic liquid: towards antibacterial, anti-electrostatic and hydrophilic nonwovens by electrospinning.

Novel antibacterial, anti-electrostatic, and hydrophilic nanofibers based on a blend containing thermoplastic polyurethane (TPU) and a room-temperature ionic liquid (IL), 1-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF6], were fabricated by electrospinning. We investigated the effect of the IL on the morphology and the physical properties of the TPU nanofibers. Nanofibers with a 'bead-on-string' morphology were obtained by electrospinning from a neat TPU solution. The incorporation of the IL, at levels as low as 1 wt%, largely suppressed the formation of beads during electrospinning, and homogeneous nanofibers were obtained. The as-spun TPU/IL composite nanofibers showed significant activity against both Escherichia coli (E coli) and Staphylococcus aureus (S. aureus), with antibacterial activities of more than four and three, respectively. This means that the antibacterial efficiencies of TPU/IL composite nanofibers toward E coli and S. aureus are 99.99% and 99.9%, respectively. Moreover, nonwoven fabrics derived from the electrospun TPU/IL composite nanofibers exhibit better stretchability, elasticity, and higher electrical conductivity compared to those made using neat TPU without an IL. Additionally, the incorporation of the IL leads to a hydrophilic surface for the TPU/IL composite nanofibers compared to hydrophobic neat TPU nanofibers. These multifunctional nanofibers with excellent antibacterial, anti-electrostatic, and mechanical properties and improved hydrophilicity are promising candidates for biomedical and wastewater treatment applications.

Salt-induced fabrication of superhydrophilic and underwater superoleophobic PAA-g-PVDF membranes for effective separation of oil-in-water emulsions.

Conventional polymer membranes suffer from low flux and serious fouling when used for treating emulsified oil/water mixtures. Reported herein is the fabrication of a novel superhydrophilic and underwater superoleophobic poly(acrylic acid)-grafted PVDF filtration membrane using a salt-induced phase-inversion approach. A hierarchical micro/nanoscale structure is constructed on the membrane surface and endows it with a superhydrophilic/underwater superoleophobic property. The membrane separates both surfactant-free and surfactant-stabilized oil-in-water emulsions under either a small applied pressure (<0.3 bar) or gravity, with high separation efficiency and high flux, which is one to two orders of magnitude higher than those of commercial filtration membranes having a similar permeation property. The membrane exhibits an excellent antifouling property and is easily recycled for long-term use. The outstanding performance of the membrane and the efficient, energy and cost-effective preparation process highlight its potential for practical applications.

Building up graphene-based conductive polymer composite thin films using reduced graphene oxide prepared by γ-ray irradiation.

In this paper, reduced graphene oxide (RGO) was prepared by means of γ -ray irradiation of graphene oxide (GO) in a water/ethanol mix solution, and we investigated the influence of reaction parameters, including ethanol concentration, absorbed dose, and dose rate during the irradiation. Due to the good dispersibility of the RGO in the mix solution, we built up flexible and conductive composite films based on the RGO and polymeric matrix through facile vacuum filtration and polymer coating. The electrical and optical properties of the obtained composite films were tested, showing good electrical conductivity with visible transmittance but strong ultraviolet absorbance.