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Anion exchange membrane fuel cells (AEMFCs), which are more economical than proton exchange membrane fuel cells (PEMFCs), stand out in the context of the rapid development of renewable energy. Superacid-catalyzed ether-free aromatic polymers have recently received a lot of attention due to their exceptional performance, but their development has been hampered by the trade-off between the dimensional stability and ionic conductivity of anion exchange membranes (AEMs). Here, we introduced fluoroketones containing different numbers of fluorinated groups (x = 0, 3 and 6) in the main chain of p-terphenyl piperidine because of the favorable hydrophobic properties of fluorinated groups. The results show that fluorinated AEMs can enhance OH - conductivity by building more aggregated hydrophilic channels while ensuring dimensional stability. The PTF6-QAPTP AEM with more fluorinated groups has the most excellent performance at 80 °C with an OH - conductivity of 142.7 mS cm -1 and a swelling ratio (SR) of only 4.55 %. Additionally, it exhibits good alkali durability, with the OH - conductivity and quaternary ammonium (QA) cation retaining at 93.45% and 92.6%, respectively, after immersion in a 2 M NaOH solution at 80 °C for 1200 h. In addition, the power density of the PTF6-QAPTP based single cell reaches 849 mW cm -2 when the current density is 1600 mA cm -2 . The PTF6-QAPTP based cell has a voltage retention of 88% after 80 h of stability testing at a constant current density of 300 mA cm -2 at 80 °C., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Anion exchange membrane fuel cells (AEMFCs) have emerged as a promising alternative to proton exchange membrane fuel cells (PEMFCs) due to their adaptability to low-cost stack components and non-noble-metals catalysts. However, the poor alkaline resistance and low OH - conductivity of anion exchange membranes (AEMs) have impeded the large-scale implementation of AEMFCs. Herein, the preparation of a new type of AEMs with crown ether macrocycles in their main chains via a one-pot superacid catalyzed reaction was reported. The study aimed to examine the influence of crown ether cavity size on the phase separation structure, ionic conductivity and alkali resistance of anion exchange membranes. Attributed to the self-assembly of crown ethers, the poly (crown ether) (PCE) AEMs with dibenzo-18-crown-6-ether (QAPCE-18-6) exhibit an obvious phase separated structure and a maximum OH - conductivity of 122.5 mS cm -1 at 80 °C (ionic exchange capacity is 1.51 meq g -1 ). QAPCE-18-6 shows a good alkali resistance with the OH - conductivity retention of 94.5% albeit being treated in a harsh alkali condition. Moreover, the hydrogen/oxygen single cell equipped with QAPCE-18-6 can achieve a peak power density (PPD) of 574 mW cm -2 at a current density of 1.39 A cm -2 ., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Poly(aryl piperidinium) (PAP) anion exchange membranes (AEMs) furnish an important avenue for the commercialization of anion exchange membrane fuel cells (AEMFCs), but their ionic conductivity and alkali resistance still need to be improved. Here, we report the synthesis of PAP AEMs with a branched structure by the acid-catalyzed reaction and compare them with the main-chain AEMs. The experimental results show that the branched AEMs have higher OH - conductivity and alkaline resistance than the poly(terphenyl piperidine) (PTPQ1) AEM. The alkaline stability and OH - conductivity of the AEMs were further improved by a flexible multi-cation crosslinker. The results show that the branched poly(p-terphenyl triphenylmethane 1-methyl piperidine) membrane crosslinked by multi-cation (PTTPQ4-40) shows an excellent OH - conductivity (155.3 mS cm -1 ) at 80 °C. The OH - conductivity of the PTTPQ4-40 membrane was maintained at 92.1% after soaking in 2 M NaOH for 1080 h at 80 °C. In addition, the peak power density (PPD) of the crosslinked PTTPQ4-40 membrane can reach 656.7 mW cm -2 . Compared to the PTPQ1 AEM, the PPD of the crosslinked PTTPQ4-40 AEM is increased by 38.6% in H 2 -O 2 . All of the results confirm that the PTTPQ4-40 AEM has excellent fuel cell application prospects., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: To study the diagnostic value of immediate color Doppler ultrasonography on traumatic hepatic hemorrhage after tissue sampling with ultrasound-guided liver biopsy and the clinical effect of its-directed local compression hemostasis at puncture-site. Methods: 132 hospitalized patients with various liver diseases underwent ultrasound-guided hepatic puncture-biopsies, including 61 cases with diffuse parenchymal and 71 cases with focal liver lesions. Immediate postoperative color Doppler ultrasonography was performed following liver biopsy. Abnormal blood flow signal was observed at hepatic puncture biopsy site, and if there were hemorrhagic signals, ultrasound-directed local compression hemostasis was performed until the bleeding signal disappeared. F-test and Chi-square test were used for statistical analysis. Results: Immediate color Doppler ultrasonography showed traumatic hemorrhage in 36.1% (22/61) and 40.8% (29/71) cases of diffuse liver disease and focal liver disease group, respectively. All hemorrhagic signals were eventually disappeared after ultrasound-directed local compression hemostasis. The median hemostasis time was 2 min in both groups, and there was no statistically significant difference in bleeding rate and hemostasis time between the two groups ( P >0.05). There were no serious complications and deaths. Conclusion: Traumatic hepatic hemorrhage along the needle puncture tract is a common accompanying condition during liver biopsy. Immediate postoperative color Doppler ultrasonography can trace bleeding signals in timely manner and direct effective compression hemostasis, so it should be used routinely to help avoid occurrence of severe hemorrhagic complications.

Root zone microbial structure is particularly complex in plants with rhizosheaths, and greater understanding of the rhizosheath may play an important role in the future development of sustainable agricultural practices. However, one important reason to focus study on rhizosheath microbial structure is that there is no definite method for rhizosheath separation. The aim of this study was to explore rhizosheath isolation methods and the diversity characteristics of microorganisms around the rhizosphere. In this study, we isolated the rhizosheath of Stipa grandis, a dominant species in desert steppe, and the microorganisms in the roots, root epidermis, rhizosheath and rhizosphere soil were extracted and sequenced by 16S rRNA and ITS. The alpha diversity index of bacteria in Stipa grandis rhizosphere soil was the greatest, followed by rhizosheath, and the alpha diversity index of endophytic bacteria in root system was the smallest. The alpha diversity index of fungi in the rhizosheath and rhizosphere soil were significantly higher than that in the root epidermis and root system. There were significant differences in bacterial community structure between the root epidermis, endophytic bacteria, rhizosheath and rhizosphere soil. Unlike bacterial community structure, the community structure of fungi in the root epidermis was similar that of endophytic fungi, but significantly different from those in rhizosheath and rhizosphere soil. This study demonstrated a feasible method for separating plant rhizosheath and root epidermis. We suggest that the root epidermis can act as the interface between the host plant root and the external soil environment. We will have to re-examine the biological and ecological significance of rhizosheath and microorganisms in rhizosheath, as well as the mechanism explaining the close relationship of the rhizosheath and the plant root epidermis. This study provides theoretical and technical guidance for the isolation of the plant rhizosheath and the study of microorganisms in plant rhizosheath., (© 2022. The Author(s).)

Anion exchange membranes (AEMs) are a crucial constituent for alkaline fuel cells. As the core component of fuel cells, the low performance AEMs restrict the development and application of the fuel cells. Herein, the trade-off between the OH - conductivity and dimensional stability was solved by constructing AEMs with adequate OH - conductivity and satisfactory alkali resistance using Tröger's base (TB) poly (crown ether)s (PCEs) as the main chain, the embedded quaternary ammonium (QA) and Na + -functionalized crown ether units as the cationic group. Crown ether is an electron donator, and can capture Na + to form Na + -functionalized crown ether units to conveniently transfer OH - and significantly promote the alkaline stability of the AEMs. The influence of the Na + -functionalized crown ether units on the performance of AEMs was studied in detail. The PCEs based AEMs show an obvious hydrophobic-hydrophilic microphase separation. These features make them ideal platforms for the OH - conduction applications. As expected, the as-prepared PCEs-QA-100% (100% is the degree of cross-linking) AEM with an ionic exchange capacity (IEC) of 2.07 meq g -1 has a high OH - conductivity of 159 mS cm -1 at 80 °C. Furthermore, the membrane electrode assemblies fabricated using the PCEs-QA-100% AEM possess a maximum power density of 291 mW cm -2 under the current density of 500 mA cm -2 ., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

A novel two-dimensional (2D) zeolitic imidazolate framework-graphene oxide hybrid nanocomposite (ZIF-L@GO) is designed as an inorganic filler in sulfonated poly(ether ether ketone) (SPEEK). ZIF-L with unique leaf-like morphology is grown in-situ on the GO sheet in aqueous media at room temperature. The terminal imidazole linker in ZIF-L@GO and the -SO 3 H in SPEEK can form acid-base pairs in the membrane interface to produce low energy proton conduction highway. Benefiting from the unique structural advantage, the hybrid SP-ZIF-L@GO membranes displayed promoted physicochemical and electrochemical performances over the pure SPEEK. The SP-ZIF-L@GO-5 achieved a proton conductivity of 0.265 and 0.0364 S cm -1 at 70 °C-100% RH and 90 °C-40% RH, 1.76- and 6.24-fold higher than pure SPEEK, respectively. Meanwhile, a single cell based on SP-ZIF-L@GO-5 had an output power up to 652.82 mW cm -2 at 60 °C, 1.45 times higher than the pure SPEEK. In addition, the durability test was performed by holding open circuit voltage (OCV) for 24 h. The SP-ZIF-L@GO-5 provided better long-term stability than the pure SPEEK. These superior performance suggests a promising application in PEMFC., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interest s or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Plasmonic Au-Ag/TiO 2 bimetallic nanocatalyst is regarded as a promising visible-light (VL) photocatalyst due to its wide light absorption and potentially enhanced activity. For its preparation, Au precursors usually contain Cl and co-impregnation/co-deposition suffers from AgCl precipitation, and consequently Au and Ag have to be sequentially supported. However, Au and Ag species of the sequential preparation are individually isolated and difficult to be homogeneously mixed. Here we report an Au-Ag plasmonic nanocatalyst achieved by plasma restructuring and activation from the sequential preparation. The isolated cationic Au and Ag species on the sequentially-prepared Au-Ag/TiO 2 sample are restructured to be homogeneously mixed and highly activated by O 2 plasma, which can be partially auto-reduced to Au-Ag bimetallic nanoparticles within the induction period of a few minutes in VL photocatalytic oxidation of CO. The Au-Ag plasmonic nanocatalyst exhibits a strongly enhanced activity in the VL photocatalytic reaction. The contribution of O 2 plasma treatment and the enhancement mechanism for the Au-Ag plasmonic nanocatalyst are disclosed., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Objective: Enhanced Recovery After Surgery (ERAS) protocols have rapidly gained popularity in multiple surgical specialties and are recognized for their potential to improve patient outcomes and decrease hospitalization costs. However, they have only recently been applied to spinal surgery. The goal in the present work was to describe the development, implementation, and impact of an Enhanced Recovery After Spine Surgery (ERASS) protocol for patients undergoing elective spine procedures at an academic community hospital., Methods: A multidisciplinary team, drawing on prior publications and spine surgery best practices, collaborated to develop an ERASS protocol. Patients undergoing elective cervical or lumbar procedures were prospectively enrolled at a single tertiary care center; interventions were standardized across the cohort for pre-, intra-, and postoperative care using standardized order sets in the electronic medical record. Protocol efficacy was evaluated by comparing enrolled patients to a historic cohort of age- and procedure-matched controls. The primary study outcomes were quantity of opiate use in morphine milligram equivalents (MMEs) on postoperative day (POD) 1 and length of stay. Secondary outcomes included frequency and duration of indwelling urinary catheter use, discharge disposition, 30-day readmission and reoperation rates, and complication rates. Multivariable linear regression was used to determine whether ERASS protocol use was independently predictive of opiate use on POD 1., Results: In total, 97 patients were included in the study cohort and were compared with a historic cohort of 146 patients. The patients in the ERASS group had lower POD 1 opiate use than the control group (26 ± 33 vs 42 ± 40 MMEs, p < 0.001), driven largely by differences in opiate-naive patients (16 ± 21 vs 38 ± 36 MMEs, p < 0.001). Additionally, patients in the ERASS group had shorter hospitalizations than patients in the control group (51 ± 30 vs 62 ± 49 hours, p = 0.047). On multivariable regression, implementation of the ERASS protocol was independently predictive of lower POD 1 opiate consumption (β = -7.32, p < 0.001). There were no significant differences in any of the secondary outcomes., Conclusions: The authors found that the development and implementation of a comprehensive ERASS protocol led to a modest reduction in postoperative opiate consumption and hospital length of stay in patients undergoing elective cervical or lumbar procedures. As suggested by these results and those of other groups, the implementation of ERASS protocols may reduce care costs and improve patient outcomes after spine surgery.

The development of anion exchange membranes (AEMs) is hindered by the trade-off of ionic conductivity, alkaline stability, and mechanical properties. Tröger's base polymers (Tb-polymers) are recognized as promising membrane materials to overcome these obstacles. Herein, the AEMs made from Tb-poly(crown ether)s (Tb-PCEs) show good comprehensive performance. The influence of crown ether on the conductivity and alkaline stability of AEMs has been investigated in detail. The formation of hydronium ion-crown ether complexes and an obvious microphase-separated structure formed by the existence of crown ether can enhance the conductivity of the AEMs. The maximum OH - conductivity of 141.5 mS cm -1 is achieved from the Tb-PCEs based AEM (Tb-PCE-1) at 80 °C in ultrapure water. The ion-dipole interaction of the Na + with crown ether can protect the quaternary ammonium from the attack of OH - to improve the alkaline stability of AEMs. After 675 h of alkaline treatment, the OH - conductivity of Tb-PCE-1 decreases by only 6%. The Tb-PCE-1-based single cell shows a peak power density of 0.202 W cm -2 at 80 °C. The prominent physicochemical properties are attributed to the well-developed microstructure of the Tb-PCEs, as revealed by TEM, AFM, and SAXS observations.

Robotic systems in surgery have developed rapidly. Installations of the da Vinci Surgical System® (Intuitive Surgical, Sunnyvale, CA, USA), widely used in urological and gynecological procedures, have nearly doubled in the United States from 2010 to 2017. Robotics systems in spine surgery have been adopted more slowly; however, users are enthusiastic about their applications in this subspecialty. Spinal surgery often requires fine manipulation of vital structures that must be accessed via limited surgical corridors and can require repetitive tasks over lengthy periods of time - issues for which robotic assistance is well-positioned to complement human ability. To date, the United States Food and Drug Administration (FDA) has approved 7 robotic systems across 4 companies for use in spinal surgery. The available clinical data evaluating their efficacy have generally demonstrated these systems to be accurate and safe. A critical next step in the broader adoption of surgical robotics in spine surgery is the design and implementation of rigorous comparative studies to interrogate the utility of robotic assistance. Here we discuss current applications of robotics in spine surgery, review robotic systems FDA-approved for use in spine surgery, summarize randomized controlled trials involving robotics in spine surgery, and comment on prospects of robotic-assisted spine surgery.

Robotics in spinal surgery has significant potential benefits for both surgeons and patients, including reduced surgeon fatigue, improved screw accuracy, decreased radiation exposure, greater options for minimally invasive surgery, and less time required to train residents on techniques that can have steep learning curves. However, previous robotic systems have several drawbacks, which are addressed by the innovative ExcelsiusGPS TM robotic system. The robot is secured to the operating room floor, not the patient. It has a rigid external arm that facilitates direct transpedicular drilling and screw placement, without requiring K-wires. In addition, the ExcelsisuGPS TM has integrated neuronavigation, not present in other systems. It also has surveillance marker that immediately alerts the surgeon in the event of loss of registration, and a lateral force meter to alert the surgeon in the event of skiving. Here, we present the first spinal surgery performed with the assistance of this newly approved robot. The surgery was performed with excellent screw placement, minimal radiation exposure to the patient and surgeon, and the patient had a favorable outcome. We report the first operative case with the ExcelsisuGPS TM , and the first spine surgery utilizing real-time image-guided robotic assistance.

Odontoid fractures are the most common cervical spine fracture in the elderly. There is considerable controversy regarding the optimal management of type II odontoid fractures in this population. We present the case of an 89-year-old woman presented with neck pain after a mechanical fall. She was neurologically intact. Computed tomography (CT) of the cervical spine revealed a Type II odontoid fracture with 4.4 mm of posterior displacement. Given the patient's extensive medical comorbidities, non-operative management with a rigid cervical orthosis was elected. The patient underwent serial imaging and routine clinical follow up. CT scan at one-year follow-up demonstrated complete osseous union. The patient's neck pain resolved and her cervical collar was discontinued. The risk benefit profile for surgical intervention in elderly patients with Type II odontoid fractures must be weighed against the morbidity associated with prolonged cervical immobilization. This case highlights the importance of serial surveillance imaging and demonstrates that complete arthrodesis can be achieved even in the elderly with prolonged cervical immobilization alone., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: The ExcelsiusGPS® (Globus Medical, Inc., Audubon, PA) is a next-generation spine surgery robotic system recently approved for use in the United States. The objective of the current study is to assess pedicle screw accuracy and clinical outcomes among two of the first operative cases utilizing the ExcelsiusGPS® robotic system and describe a novel metric to quantify screw deviation., Methods: Two patients who underwent lumbar fusion at a single institution with the ExcelsiusGPS® surgical robot were included. Pre-operative trajectory planning was performed from an intra-operative CT scan using the O-arm (Medtronic, Inc., Minneapolis, MN). After robotic-assisted screw implantation, a post-operative CT scan was obtained to confirm ideal screw placement and accuracy with the planned trajectory. A novel pedicle screw accuracy algorithm was devised to measure screw tip/tail deviation distance and angular offset on axial and sagittal planes. Screw accuracy was concurrently determined by a blinded neuroradiologist using the traditional Gertzbein-Robbins method. Clinical variables such as symptomatology, operative data, and post-operative follow-up were also collected., Results: Eight pedicle screws were placed in two L4-L5 fusion cases. Mean screw tip deviation was 2.1 mm (range 0.8-5.2 mm), mean tail deviation was 3.2 mm (range 0.9-5.4 mm), and mean angular offset was 2.4 degrees (range 0.7-3.8 degrees). All eight screws were accurately placed based on the Gertzbein-Robbins scale (88% Grade A and 12% Grade B). There were no cases of screw revision or new post-operative deficit. Both patients experienced improvement in Frankel grade and Karnofsky Performance Status (KPS) score by 6 weeks post-op., Conclusion: The ExcelsiusGPS® robot allows for precise execution of an intended pre-planned trajectory and accurate screw placement in the first patients to undergo robotic-assisted fusion with this technology., Competing Interests: Competing interestsBJ: Consultant for Longeviti Neuro Solutions. AKA: None. CCZ: received travel grant to attend resident education course from Globus and Nuvasive. She is supported by an AO Spine fellowship grant. SK: None. AZ: None. CM: Consultant for Augmedics. JG: None. AMB: None. AB: None. NC: employee, owns stock, and receives royalties from Globus Medical; patent holder, Globus Medical. NT: is an inventor of a device manufactured by Globus Medical, Inc., which was used in the study discussed in this publication. He is entitled to royalty payments on future sales of the device and he is a paid consultant to Globus Medical, Inc. This arrangement has been reviewed and approved by the Johns Hopkins University in accordance with its conflict of interest policies., (© The Author(s) 2018.)

The Excelsius GPS (Globus Medical, Inc.) was approved by the FDA in 2017. This novel robot allows for real-time intraoperative imaging, registration, and direct screw insertion through a rigid external arm-without the need for interspinous clamps or K-wires. The authors present one of the first operative cases utilizing the Excelsius GPS robotic system in spinal surgery. A 75-year-old man presented with severe lower back pain and left leg radiculopathy. He had previously undergone 3 decompressive surgeries from L3 to L5, with evidence of instability and loss of sagittal balance. Robotic assistance was utilized to perform a revision decompression with instrumented fusion from L3 to S1. The usage of robotic assistance in spinal surgery may be an invaluable resource in minimally invasive cases, minimizing the need for fluoroscopy, or in those with abnormal anatomical landmarks. The video can be found here: https://youtu.be/yVI-sJWf9Iw .

To achieve highly conductive and stable anion exchange membranes (AEMs) for fuel cells, novel triblock copolymer AEMs bearing flexible side chain were synthesized. The triblock structure and flexible side chain are responsible for the developed hydrophilic/hydrophobic phase separated morphology and well-connected ion conducting channels, as confirmed by transmission electron microscopy. As a result, the triblock copolymer AEMs with flexible side chain (ABA-TQA- x) demonstrated considerably higher conductivities, up to 130.5 mS cm -1 at 80 °C, than the AEMs with monocation side chain (ABA-MQA). Furthermore, the long alkyl spacer between the backbone and quaternary ammonium groups, as well as long intercation spacer limits the water swelling of the membranes to some degree, resulting in good alkaline stability. The ABA-TQA-44 membrane retained 84.7% and 83.1% of its original conductivity and ionic exchange capacity, respectively, after immersed in a 1 M aqueous KOH solution at 80 °C for 480 h. Furthermore, the peak power density of a H 2 /O 2 single cell using ABA-TQA-44 is 204.6 mW cm -2 at a current density of 500 mA cm -2 at 80 °C.

Two-dimensional nanosheets of late show great promise as novel materials for size-selective separation membranes of high efficiency. Herein, we demonstrate a novel laminated nanofiltration membrane for fast water purification and organic solvent nanofiltration using the 1 nm-thick and 50 nm-wide nickel hydroxide nanosheets that are facilely prepared by a green chemistry method. The resulting membranes exhibit uniform and flectional two-dimensional laminated structure. With about 1 nm high laminated channels, they allow super-fast transport of water and organic solvents. The water and organic fluxes are three orders of magnitude higher than commercially available polymeric nanofiltration membranes. In addition, the membranes have high retention for organic dyes in aqueous and organic solutions. Typically, the 3.18 μm-thick membrane with the molecular weight cut-off of 328 g mol -1 has an outstanding pure water flux of 99 L m -2 h -1 bar -1 and up to 97% rejection for direct yellow dye molecules. The newly developed nickel hydroxide nanosheets and the subsequent membranes have great potential application in water purification, organic solvent filtration and electronic devices.

With the intention of optimizing the performance of anion-exchange membranes (AEMs), a set of imidazolium-functionalized poly(arylene ether sulfone)s with densely distributed long flexible aliphatic side chains were synthesized. The membranes made from the as-synthesized polymers are robust, transparent, and endowed with microphase segregation capability. The ionic exchange capacity (IEC), hydroxide conductivity, water uptake, thermal stability, and alkaline resistance of the AEMs were evaluated in detail for fuel cell applications. Morphological observation with the use of atomic force microscopy and small-angle X-ray scattering reveals that the combination of high-local-density-type and side-chain-type architectures induces distinguished nanophase separation in the AEMs. The as-prepared membranes have advantages in effective water management and ionic conductivity over traditional main-chain polymers. Typically, the conductivity and IEC were in the ranges of 57.3-112.5 mS cm(-1) and 1.35-1.84 mequiv g(-1) at 80 °C, respectively. Furthermore, the membranes exhibit good thermal and alkaline stability and achieve a peak power density of 114.5 mW cm(-2) at a current density of 250.1 mA cm(-2). Therefore, the present polymers containing clustered flexible pendent aliphatic imidazolium promise to be attractive AEM materials for fuel cells.

Stimuli-responsive nanoporous membranes have attracted increasing interest in various fields due to their abrupt changes of permeation/separation in response to the external environment. Here we report ultrathin pH-sensitive nanoporous membranes that are easily fabricated by the self-assembly of poly(acrylic acid) (PAA) in a metal hydroxide nanostrand solution. PAA-adsorbed nanostrands (2.5-5.0 nm) and PAA-Cu(II) nanogels (2.0-2.5 nm) grow competitively during self-assembly. The PAA-adsorbed nanostrands are deposited on a porous support to fabricate ultrathin PAA membranes. The membranes display ultrafast water permeation and good rejection as well as significant pH-sensitivity. The 28 nm-thick membrane has a water flux decrease from 3740 to 1350 L m(-1)  h(-1)  bar(-1) (pH 2.0 to 7.0) with a sharp decrease at pH 5.0. This newly developed pH-sensitive nanoporous membranes may find a wide range of applications such as controlled release and size- and charge-selective separation., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A series of phenolphthalein-based poly(arylene ether sulfone nitrile)s (PESN) multiblock copolymers containing 1-methylimidazole groups (ImPESN) were synthesized to prepare anion exchange membranes (AEMs) for alkaline fuel cells. The ion groups were introduced selectively and densely on the unit of phenolphthalein as the hydrophilic segments, allowing for the formation of ion clusters. Strong polar nitrile groups were introduced into the hydrophobic segments with the intention of improving the dimensional stability of the AEMs. A well-controlled multiblock structure was responsible for the well-defined hydrophobic/hydrophilic phase separation and interconnected ion-transport channels, as confirmed by atomic force microscopy and small angle X-ray scattering. The ImPESN membranes with low swelling showed a relatively high water uptake, high hydroxide ion conductivity together with good mechanical, thermal and alkaline stability. The ionic conductivity of the membranes was in the range of 3.85-14.67×10(-2) S·cm(-1) from 30 to 80 °C. Moreover, a single H2/O2 fuel cell with the ImPESN membrane showed an open circuit voltage of 0.92 V and a maximum power density of 66.4 mW cm(-2) at 60 °C.

Oily wastewater is generated in diverse industrial processes, and its treatment has become crucial due to increasing environmental concerns. Herein, novel ultrathin nanoporous membranes of cellulose nanosheets have been fabricated for separation of oil-in-water nanoemulsions. The fabrication approach is facile and environmentally friendly, in which cellulose nanosheets are prepared by freeze-extraction of a very dilute cellulose solution. The as-prepared membranes have a cellulose nanosheet layer with a cut-off of 10-12 nm and a controllable thickness of 80-220 nm. They allow ultrafast water permeation and exhibit excellent size-selective separation properties. A 112 nm-thick membrane has a water flux of 1620 l m(-2) h(-1) bar(-1) and a ferritin rejection of 92.5%. These membranes have been applied to remove oil from its aqueous nanoemulsions successfully, and they show an ultrafast and effective separation of oil-in-water nanoemulsions. The newly developed ultrathin cellulose membranes have a wide application in oily wastewater treatment, separation and purification of nanomaterials.

Two kinds of novel multiblock poly(arylene ether sulfone)s were synthesized via block copolycondensation of telechelic oligomers as a starting material for the preparation of anion-exchange membranes (AEMs). The as-synthesized copolymers have extremely similar main chains. The difference is that the benzylmethyl groups for one are located on the fluorene-sulfone segments and they are located on the isopropylidene-sulfone segments for the other. The benzylmethyl moieties served as precursors to cationic sites and were brominated using N-bromosuccinimide (NBS) and then quaternized with N,N,N',N'-tetramethyl-1,6-diaminohexane (TMHDA). Controlled bromination and quaternization at specific positions of the benzylmethy-containing fluorene-sulfone segments and isopropylidene-sulfone segments can be achieved. 1H NMR spectroscopy, Fourier transform infrared spectroscopy, and gel permeation chromatography were used to characterize the as-synthesized copolymers. Distinct microphase separation in the as-prepared AEMs was observed using small-angle X-ray scattering and transmission electron microscopy. The AEM containing fluorene-sulfone segments (IEC=1.89 meq·g(-1)) showed higher ionic conductivity and methanol permeability than that containing isopropylidene-sulfone segments (IEC=2.03 meq·g(-1)). Moreover, the former showed better alkaline stability than the latter.

Nanoporous membranes with superior separation performance have become more crucial with increasing concerns in functional nanomaterials. Here novel ultrahigh permeable nanoporous membranes have been fabricated on macroporous supports by self-assembly of anionic polymer on copper hydroxide nanostrand templates in organic solution. This facile approach has a great potential for the fabrication of ultrathin anionic polymer membranes as a general method. The as-fabricated self-assembled membranes have a mean pore size of 5-12 nm and an adjustable thickness as low as 85 nm. They allow superfast permeation of water, and exhibit excellent size-selective separation properties and good fouling resistance for negatively-charged solutes during filtration. The 85 nm thick membrane has an ultrahigh water flux (3306 l m(-2) h(-1) bar(-1)) that is an order of magnitude larger than commercial membranes, and can highly efficiently separate 5 and 15 nm gold nanoparticles from their mixtures. The newly developed nanoporous membranes have a wide application in separation and purification of biomacromolecules and nanoparticles.

Cell encapsulation by locking the interfacial microgels in a water-in-oil Pickering emulsion has currently been attracting intensive attention because of the biofriendly reaction condition. Various kinds of functional microgels can only stabilize an oil-in-water Pickering emulsion, and it is thus difficult to encapsulate cells in the emulsion where the cells are usually dispersed in the continuous phase. Herein, we introduce a facile method for preparing cell-embedded colloidosomes in an oil-in-water emulsion via polyelectrolyte complexation. Escherichia coli (E. coli) was chosen as a model cell and embedded in the thin shell of chitosan/poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAM-co-AAc)) microcapsules. This is beneficial for expressing cell function because of the little resistance of mass exchange between the embedded cells and the external environment. Cells can be used in biocatalysis or biomedicine and our product will hold great promises to improve the performance in those fields. The synthesis route presents a platform to prepare cell-embedded microcapsules in an oil-in-water Pickering emulsion in a facile and biocompatible way. First, an emulsion stabilized by P(NIPAM-co-AAc) microgels was prepared. Then, the interfacial microgels in the emulsion were locked by chitosan to form colloidosomes. The mechanism of cell encapsulation in this system was studied via fluorescent labeling. The viability of E. coli after encapsulation is ca. 90%. Encapsulated E. coli is able to metabolize glucose from solution, and exhibits a slower rate than free E. coli. This demonstrates a diffusion constraint through the colloidosome shell.

In order to understand the improvement effect of potassium (K) on the catalytic activity of iron-loaded calcined scallop shell (CS) for the steam reforming tar derived from biomass, various K precursors were applied for the catalyst preparation. It is found that pompom-like iron-based particles with a mesoporous structure were easily formed on the surface of calcined scallop shell (CS) when K2CO3 was used as K precursor while no such kind of microsphere was formed when other kinds of K precursors such as KOH and KNO3 were applied. The optimum K-loading amount for the preparation of this catalyst was investigated. Based on the experimental results obtained, a mechanism for the formation of these microspheres was proposed. This pompom-like potassium-promoted iron-based catalyst showed a better catalytic activity and reusability for the steam reforming of tar derived from lignin., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

At room temperature, the enhanced effect of water vapor on ozone catalytic oxidation (OZCO) of formaldehyde to CO2 over MnOx catalysts and the reaction stability was reported. In a dry air stream, only below 20% of formaldehyde could be oxidized into CO2 by O3. In humid air streams (RH≥55%), ∼100% of formaldehyde were oxidized into CO2 by O3 and the reaction stability was significantly enhanced. Meanwhile, in situ Diffuse Reflectance Infrared Fourier Transform (DRIFT) spectra of OZCO of HCHO demonstrate that the amount of both monodentate and bidentate carbonate species on MnOx, in the dry stream, increased gradually with time on stream (TOS). However, in the humid stream, almost no accumulation of carbonate species on the catalysts was observed. To clarify the enhanced mechanism, formaldehyde surface reactions and CO2 adsorption/desorption on the fresh, O3 and O3+H2O treated MnOx catalysts were examined comparatively., (Copyright © 2012 Elsevier B.V. All rights reserved.)

This work presents a new approach for the synthesis of multiresponsive composite microspheres of PNIPAM/chitosan. The resulting microspheres in a sandwich structure with PNIPAM nanoparticles embedded in the crosslinked chitosan matrix were characterized. Compared to other preparation methods, this proposed technique not only is a facile route but also endows the microspheres a desirable structure. The products undergo a temperature induced volume phase transition and exhibit an appreciable pH response. They are further tested as drug carriers to investigate potential application. The encapsulation efficiency in acidic environment (pH=4.0) is 73.5% and much higher than that in neutral (20.3%, pH=6.9) and alkaline (15.1%, pH=9.2) environments. The release of the drug from the microspheres can be controlled by pH and temperature., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background: We used recombinant adeno-associated virus vector of adiponectin (AAV2/1-Acrp30) to study the effects of increased levels of adioponectin (by the administration of rAAV2/1-Acrp30) on arteriosclerosis, glucose and lipid metabolism in Goto-Kakizaki (GK) rats with arteriosclerosis., Methods: Thirty GK rats with arteriosclerosis were divided into 3 equal groups: control group 1, control group 2 and the rAAV2/1-Acrp30-administered group. Saline, virus vector or rAAV2/1-Acrp30 (10 12 ng/ml) vector genomes administered to the rats in the corresponding group by intramuscular injection to the posterior limb by single administration, respectively. After 8 weeks, fasting blood glucose, 2-hour postprandial blood glucose, glycosylated haemoglobin, serum insulin, serum total cholesterol, triglycerides, high-density lipoprotein and low-density lipoprotein were measured in each group, and the ultrastructure of the aorta was seen by light and electron microscopy., Results: Compared with control groups 1 and 2, in the rAAV2/1-Acrp30 group, there was a decrease in urine volume, fasting blood glucose, 2-hour postprandial blood glucose, glycosylated haemoglobin, serum total cholesterol, triglycerides and low-density lipoprotein, and an increase in body weight and high-density lipoprotein (p< 0.05), while the level of serum insulin was not changed (p>0.05). Ultrastructure studies of the aorta showed that aortosclerosis in the rAAV2/1-Acrp30-administered group was less, and fewer lipid droplet vacuoles were seen in the vascular endothelial cytoplasm. Also various cell organelles and internal elastic lamina were seen, and there was no formation of lipid droplet and foam cells in the cytoplasm of the media of the smooth muscle., Conclusion: Adiponectin could improve blood glucose and lipid parameters and decrease atherosclerosis in the aorta of GK rats., (Copyright 2012, NMJI.)

The COMPASS (condensed-phase optimized molecular potentials for atomistic simulation studies) force field with two sets of partial atomic charges of water was used to simulate adsorption and diffusion behavior of water/methanol and water/ethanol mixtures in zeolite 4A at 298 K. The adsorption of alcohol first increased and then decreased with increasing pressure, whereas the adsorption of water increased progressively until an adsorption equilibrium was reached. Both the adsorbed molecules and the zeolite framework were treated as a fully flexible model in MD simulations. The simulation results show that the effects of the size and steric hindrance of the diffusing molecules on diffusivity are significant. The diffusivity of water, methanol, and ethanol molecules decreases by 1 order of magnitude in the order of water > methanol > ethanol. The diffusivity of water molecules depends on the mass fraction and the partial charges of water in zeolite 4A. The ethanol and methanol molecules have restricted motion through the alpha-cages, whereas the water molecules can easily pass through the alpha-cages window at low feed alcohol concentrations. And the extent of hydrogen bonding increased with increasing water concentration.

Bis(trialkylsilyl) precursor was used to modify polymer membranes for the first time. Novel organic-inorganic hybrid membranes of poly(vinyl alcohol) (PVA)/1,2-bis(triethoxysilyl)ethane (BTEE) were prepared through a sol-gel method for pervaporation dehydration of ethanol. The permeability and selectivity of the membranes were improved simultaneously. The physicochemical properties of the hybrid membranes were investigated. With increasing BTEE content, the amorphous region in the hybrid membranes increased and became more compact. Phase separation took place in the hybrid membranes containing abundant BTEE, and silica particles distributed in the PVA matrix homogeneously. Compared to PVA membranes, the hybrid membranes exhibit high thermal stability and improved separation performances. Silica-hybrids reduced significantly the swelling of PVA membranes in an aqueous solution. The Flory-Huggins interaction parameter of water with membranes chi13 increased with increasing BTEE content, whereas that of ethanol with membranes chi23 decreased. Diffusion behavior of water and ethanol through the membranes were analyzed using the Maxwell-Stefan equation. When BTEE content was below 6 wt%, diffusion coefficient of water D13 increased remarkably and that of ethanol D23 decreased slightly.

Chitosan-silica hybrid membranes (CSHMs) were prepared by cross-linking chitosan (CS) with 3-aminopropyl-triethoxysilane (APTEOS). The dynamic behaviors of the CS membrane and the CSHM were investigated in pervaporation (PV) of methanol/dimethyl carbonate (MeOH/DMC) mixtures. The membranes were characterized by X-ray diffraction (XRD), contact angle meter, scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The transition state of PV processes were studied. During the PV processes, the amorphous region of the membranes increases and the contact angle between MeOH and the membrane decreases within a range of operating time and then remains almost constant implying a reconstruction occurred on the membrane surface. The silica is well distributed in the CSHM matrix and the thermal stability of the CSHM is enhanced. The time for a PV process to reach a steady state decreases with increasing MeOH concentration or feed temperature, and it is longer for the CSHM than the CS membrane under the same operating condition. Swelling experiments show that the degree of swelling (DS) is greatly depressed by cross-linking CS with APTEOS. Sorption data indicate that the selectivity of solubility and diffusion of the CSHM are greatly improved over the CS membrane. The CSHM presents superior separation behaviors over other membranes with a flux of 1265 g/(hm(2)) and separation factor of 30.1 in PV separation of 70 wt% MeOH in feed at 50 degrees C.

Atomic hydrogen plays important roles in chemical vapor deposition of functional materials, plasma etching, and surface cleaning. The present work introduces the fundamental principle to determine atomic hydrogen density via optical emission spectroscopy using Ar as an actinometer, and also reports the experimental results of atomic hydrogen density in the DBD discharge hydrogen plasmas. The variations of atomic hydrogen density and the hydrogen dissociation fraction as a function of pressure were calculated based on some of the available electron-impact excitation cross section and quenching cross sections in the literatures. In this work, as the pressure increases from 0.32 to 5.1 kPa, the hydrogen dissociation fraction decreases from 5.2% to 0.089%, and the atomic hydrogen density decreases from 4.9 x 10(15) cm(-3) to 1.3 x 10(15) cm(-3). The variations of H atom Balmer lines and Ar (750.4 nm) emission intensity as functions of gas pressure, discharge voltage, and frequency were also investigated.

Atomic hydrogen plays important roles in chemical vapor deposition of functional materials, plasma etching and new approaches to chemical synthesis of hydrogen-containing compounds. The present work reports experimental determinations of atomic hydrogen near the grounded electrode in medium-pressure dielectric barrier discharge hydrogen plasmas by means of molecular beam threshold ionization mass spectrometry (MB-TIMS). At certain discharge conditions (a.c. frequency of 24 kHz, 28 kV of peak-to-peak voltage), the measured hydrogen dissociation fraction is decreased from approximately 0.83% to approximately 0.14% as the hydrogen pressure increases from 2.0 to 14.0 Torr. A simulation method for extraction of the approximate electron beam energy distribution function in the mass spectrometer ionizer and a semi-quantitative approach to calibrate the mass discrimination effect caused by the supersonic beam formation and the mass spectrometer measurement are reported., (Copyright 2005 John Wiley & Sons, Ltd.)