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In order to investigate the relationship between the side chain topology of comb-shaped anion exchange membranes (AEMs) and membranes properties, two types of hydrophobic side chains attached AEMs that based on QAPPO are synthesized, namely side chains grafted onto backbones and side chains tethered to cations, resulting in AxSB-QAPPO and AxSC-QAPPO AEMs, respectively. Compared with AxSC-QAPPO, the side chains in AxSB-QAPPO AEMs are more inclined to facilitate the membranes to form broad and interconnected ion channels, promoting ion conduction and providing more free volume for the external water to enter the membranes, which are benefit to improving the ionic conductivity and chemical stability of the AxSB-QAPPO samples. At 80 °C, the OH− conductivity of A8SB-QAPPO is 101.2 mS cm−1, while the values for A8SC-QAPPO and QAPPO are only 56.1 and 48.5 mS cm−1 respectively. After the stability test, the weight and IC retentions of A8SB-QAPPO are 83.0% and 77.0%, respectively, while the values for A8SC-QAPPO are 76.5% and 68.0%, respectively, and the values for QAPPO are 56.0% and 42.0%, respectively. Besides, the influence of side chain length on the membranes properties is studied. The chemical stability for both AxSB-QAPPO and AxSC-QAPPO AEMs is enhanced by increasing the side chain length from 5 to 14. After the stability test, the IEC retentions of A5SB-QAPPO, A8SB-QAPPO, A14SB-QAPPO, A5SC-QAPPO, A8SC-QAPPO and A14SC-QAPPO are 60.0%, 78.0%, 90.0%, 49.0%, 70.0% and 75.0%, respectively. While for ionic conductivity, the AEMs with the side chain length of 8 exhibit the highest OH− conductivity. Hence, we speculate that the comb-shaped AEMs with hydrophobic side chains attached to backbones (AxSB-QAPPO) are superior to the membranes with the side chains linked to cations (AxSC-QAPPO), and the membranes performance can be further optimized by adjusting the side chain length.

Summary Artificial N2 fixation is one of the most important industrial processes for human beings. However, the current Haber-Bosch process based on fossil fuel suffers from unsustainability and a low N2 to NH3 conversion. Here, we report a magnesium chloride cycle for the synthesis of NH3 from N2 and H2O at atmospheric pressure. In this cycle, N2 reacts with Mg to form Mg3N2. Mg and Cl2 are produced by the electrolysis of molten MgCl2. NH4Cl is used to hydrogenolyze Mg3N2 to produce NH3, with anhydrous MgCl2 being regenerated. The cycle is closed via the reverse Deacon reaction to convert Cl2 to HCl, which is captured as NH4Cl with the recyclable NH3. This indirect electrosynthesis produces NH3 at an industry-acceptable rate with zero CO2 emission, a coulombic efficiency >92%, and an energy consumption of ∼14.1 kWh/kg-NH3.

Zinc anode is promising for various aqueous batteries due to its low cost and high theoretical specific capacity. However, poor cycling stability caused by dendritic growth seriously hampered its widespread application. Herein, we demonstrate that by using an anion-exchange membrane, quaternary ammonia poly (N-methyl-piperidine-co-p-terphenyl) (QAPPT), as the separator, the damage from short circuits can be completely prevented. More details reveal that when approaching the QAPPT membrane, Zn dendrites perform a bending growth rather than pierce through it, which helps achieve a superior cycling stability without any short. The bending growth can be ascribed to a variation of electrolyte concentration at the electrode/membrane interface where Zn electrodeposited at a very low rate in the direction perpendicular to the membrane. By using QAPPT membrane, an ultra-stable Ni–Zn full cell is then realized. This finding may pave a facile way to solve the problems associated with dendrites for diverse alkaline Zn-based batteries.

Two coordination polymers (CPs) based on Cu(II) of {[Cu(L)]·(CH3CN)}n (1) and {[Cu2(L)2(H2O)] 3H2O}n (2) (H2L = 5-(benzimidazole-1-yl)isophthalic acid) were prepared through the hydrothermal method and then characterized by elemental analysis and single-crystal X-ray diffraction. In addition, the magnetic performances of the complex 1 and the complex 2 were investigated, which revealed antiferromagnet interactions between the centers of the magnet. The preventative effect of the compounds on periodontitis was assessed, and the detailed mechanism was investigated. First, the inhibition of compound 1 or compound 2 against dental plaque formation was evaluated. Afterward, real-time RT-PCR was implemented to detect the expression of p53 and nf-κb in periodontal mucosal cells.

Core–shell structured catalysts have been widely investigated for fuel cell applications in the recent decade. The skin-substrate interaction has provided a well tunable basis for the design of better catalysts. Herein, we report an implementation of fabricating a Pd skin onto the AuCu intermetallic nanoparticles (denoted as PdSAuCu iNPs), and its exceptionally high activity towards the oxygen reduction reaction (ORR) in alkaline media. The structure of PdSAuCu iNPs was well characterized through combining a variety of techniques, including high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) and energy dispersive X-ray (EDX) line scanning analysis, synchrotron X-ray diffraction patterns (SXRD), X-ray photoelectron spectra (XPS), X-ray fluorescence analysis (XRF), and electrochemical measurements. The AuCu intermetallic core was identified to be fully wrapped by a Pd skin with 2–3 atomic layers. The catalytic activity of PdSAuCu iNPs towards the ORR in alkaline is more than 8-times higher in surface-specific activity (SA), and 20-times higher in mass-specific activity (MA), than that of the commercial Pt/C catalyst, and remains reasonably stable in thousands cycles of potential sweep. Such an outstanding performance is attributed to the reduction in the oxygen affinity of the Pd skin caused by a proper and stable shrink in Pd lattice induced by the AuCu intermetallic substrate.

Background E-cigarettes have grown popular. The most common pattern is dual use with conventional cigarettes. Dual use has raised concerns that it might delay quitting of cigarette smoking. This study examined the relationship between long-term use of e-cigarettes and smoking cessation in a 2-year period. Methods A nationally representative sample of 2028 US smokers were surveyed in 2012 and 2014. Long-term e-cigarette use was defined as using e-cigarettes at baseline and follow-up. Use of e-cigarettes only at baseline or at follow-up was defined as short-term use. Non-users did not use e-cigarettes at either survey. Quit attempt rates and cessation rates (abstinent for 3 months or longer) were compared across the three groups. Results At 2-year follow-up, 43.7% of baseline dual users were still using e-cigarettes. Long-term e-cigarette users had a higher quit attempt rate than short-term or non-users (72.6% vs 53.8% and 45.5%, respectively), and a higher cessation rate (42.4% vs 14.2% and 15.6%, respectively). The difference in cessation rate between long-term users and non-users remained significant after adjusting for baseline variables, OR=4.1 (95% CI 1.5 to 11.4) as did the difference between long-term users and short-term users, OR=4.8 (95% CI 1.6 to 13.9). The difference in cessation rate between short-term users and non-users was not significant, OR=0.9 (95% CI 0.5 to 1.4). Among those making a quit attempt, use of e-cigarettes as a cessation aid surpassed that of FDA-approved pharmacotherapy. Conclusions Short-term e-cigarette use was not associated with a lower rate of smoking cessation. Long-term use of e-cigarettes was associated with a higher rate of quitting smoking.

Introduction Electronic cigarette (e-cigarette) designs may be described as "closed" or "open." Closed systems are disposable or reloadable with prefilled cartridges (cigalikes). Open systems feature a prominent chamber (tank), refillable with e-liquid. This study examined user design preference and its association with smoking cessation. Methods A probability sample of current e-cigarette users ( n =923) among adult ever smokers ( n =6,560) in the U.S. was surveyed online between February 28 and March 31, 2014, and analyzed in September 2014. Photos of e-cigarette devices were presented alongside survey questions to facilitate respondents' understanding of the questions. Results Most e-cigarette users were exclusive users of one design: 51.4% used only closed systems and 41.1% used only open systems, with 7.4% using both. Former smokers were more likely to use open systems than current smokers (53.8% vs 35.2%, p =0.002). Current smokers who attempted to quit in the last 12 months were more likely to use open systems than those who did not (41.4% vs 27.7%, p =0.029). Open system users were more likely than closed system users to use e-cigarettes daily (50.2% vs 22.9%, p p p p =0.001). Conclusions Preference of e-cigarette design is associated with smoking cessation. A device's ability to deliver more nicotine and its flexibility in use might contribute to users' success in quitting smoking.

The photoelectrochemical water splitting is an artificial photosynthetic approach that could provide a sustainable supply of clean energy, however, the sluggish kinetics of the oxygen evolution reaction (OER) has been a bottleneck to the solar-to-chemical conversion. Here we report an implementation of 8% efficient photoanode based on the photoelectrolysis of saturated NaCl solution. Replacing the OER with the chlorine evolution reaction (CER) has transformed both the thermodynamic basis and the kinetic process of the photoelectrolysis, more chemical energy can be produced with much less driving force. The RuO2/TiO2/n-Si photoanode exhibits a high rate of photoelectrochemical conversion (35 mA/cm2 at equilibrium potential), which steadily and exclusively produces Cl2 without detectable O2. Keywords: Photoelectrolysis, Chlorine evolution reaction, Photoanode, Si, RuO2

CaSO4·0.5H2O whiskers were successfully synthesized by hydrothermal process, in which phosphogypsum (PG) was employed as precursors. The effect of the hexadecyltrimethylammonium bromide (CTAB) on the formation of phosphogypsum-based CaSO4·0.5H2O whiskers was investigated in details. Results indicated that the average diameter and length of as-prepared CaSO4·0.5H2O whiskers with rough surface were about 0.15-2.5μm and 10-50 μm, respectively. The added CTAB templates would effectively guided the selective growth of CaSO4·0.5H2O particles which led to formation of whiskers with high aspect ratios.

Purpose Although negative-pressure wound therapy (NPWT) for complicated wounds has been extensively studied, it is rarely used in cases involving a submandibular fistula due to radiation-induced osteoradionecrosis of the mandible. This study aimed to investigate the efficacy of NPWT for submandibular fistulas after reconstruction for osteoradionecrosis. Patients and Methods Nine patients with submandibular fistulas after reconstruction for osteoradionecrosis treated with NPWT between 2011 and 2014 were included in the study. The wound healing was documented. Results The NPWT device was removed postoperatively between days 7 and 12 (mean duration, 9.6 days). The wound bed was filled with healthy granulation tissue, and successful healing by second intention was observed in all patients within 2 weeks. No complications were observed. The follow-up ranged from 4 to 27 months (mean, 18 months); the fistulas exhibited excellent healing, and no recurrence or infection was observed. Conclusions NPWT is a safe, effective technique for managing submandibular fistulas after reconstruction for osteoradionecrosis.

Anion exchange membrane fuel cells (AEMFCs) have been developed as promising energy conversion devices for stationary and mobile applications due to their potentially low cost. To realize high-performance AEMFCs, new polymeric membranes are needed that are highly conductive and chemically stable. Here we report a systematic study of anion exchange membranes (AEMs) with multiple cations per side chain site to demonstrate how this motif can boost both the conductivity and stability of poly(2,6-dimethyl-1,4-phenylene oxide)-based AEMs. The highest conductivity, up to 99 mS/cm at room temperature, was observed for a triple-cation side chain AEM with 5 or 6 methylene groups between cations. This conductivity was considerably higher than AEM samples based on benzyltrimethylammonium or benzyldimethylhexylammonium groups with only one cation per side chain site. In addition to high conductivity, the multication side chain AEMs showed good alkaline and dimensional stabilities. High retention of ion exchange capaci...

Improved properties arise in transition metal dichalcogenide (TMDC) materials when they are stacked onto insulating hexagonal boron nitride (h-BN). Therefore, the scalable fabrication of TMDCs/h-BN heterostructures by direct chemical vapor deposition (CVD) growth is highly desirable. Unfortunately, to achieve this experimentally is challenging. Ideal substrates for h-BN growth, such as Ni, become sulfides during the synthesis process. This leads to the decomposition of the pregrown h-BN film, and thus no TMDCs/h-BN heterostructure forms. Here, we report a thoroughly direct CVD approach to obtain TMDCs/h-BN vertical heterostructures without any intermediate transfer steps. This is attributed to the use of a nickel-based alloy with excellent sulfide-resistant properties and a high catalytic activity for h-BN growth. The strategy enables the direct growth of single-crystal MoS2 grains of up to 200 μm2 on h-BN, which is approximately 1 order of magnitude larger than that in previous reports. The direct band g...

Self-assembly of Pt-based truncated octahedral crystals into frameworks has been demonstrated in this paper by suitably adjusting the reactant concentrations and temperature. This approach allows for control of Pt or Pt-based nano-crystals with subnanometer-size as building blocks for metal-frameworks (MFs): sub-micron porous tubes (SMPBs) and mesh (M). Both the Pt-based MFs exhibit enhanced activity and better stability for the oxygen reduction reaction (ORR) and methanol-oxidation reaction (MOR) than PtMFs. The mass activity (MA) of the Pt4Cu-SMPBs (0.619 A mg−1@0.9 V) exhibited 5.12 times enhancement over the commercial Pt/C (0.121 A mg−1@0.9 V) catalyst towards the ORR and the value is well beyond the U.S. Department of Energy's 2017 target (0.44 A mgPt−1 @0.9 V). After 8000 cycles of accelerated durability test, the MA of the Pt4Cu-SMPBs (0.411 A mg−1@0.9 V) was still greater than the values of the Pt/C. These metal-framework materials provide a new direction to obtain highly open nanostructures which would readily improve their catalytic properties in both activity and durability while reducing their loading.

Liquid metal, such as Ga, has been demonstrated to be a good catalyst to grow uniform graphene at about 1000 °C. However, at reduced temperature, the high surface tension of Ga causes the limited spreading-ability over the supporting substrate, which prevents the formation of large-area graphene. Here we present that the addition of Cu could efficiently decrease the surface tension of Ga, thus achieving a larger coverage. We succeeded in growing large-area, uniform and single-layer graphene at 800 °C by atmospheric chemical vapour deposition using CH4 as the carbon source.

Alkaline polymer electrolyte fuel cells (APEFCs) are a class of promising energy conversion devices that are attracting ever-growing attention from the academic and industrial energy technology communities. Considerable efforts have been made towards the development of advanced alkaline polymer electrolytes (APEs), and manipulating the balance between high ionic conductivity and low swelling degree is consistently one of the most important trade-offs in APE design. Constructing hydrophilic/hydrophobic microphase-separated morphologies in APEs has long been accepted as an effective way to optimize the ionic conductivity of these materials. However, not all patterns of phase separation lead to high APE ion conductive efficiency. Here we compare two kinds of polysulfone-based APE materials (i.e. self-aggregated quaternary ammonium polysulfone (aQAPSF) and pendant quaternary ammonium polysulfone (pQAPSF)). Experimental and simulation observations unambiguously reveal the existence of distinctly different patterns of microphase separation in aQAPSF and pQAPSF. In aQAPSF, the hydrophobic side chains residing apart from the quaternary ammonium (QA) group help to build broad and percolated pathways, which contribute to boosting the ion conductive efficiency of the material. The aQAPSF membrane with IEC equal to 0.98 mmol g−1 shows ionic conductivity as high as 108.3 mS cm−1 at 80 °C. While in pQAPSF, the introduction of a side chain between the backbone and the cation locates the QA group away from the backbone and helps to build strong hydrophobic networks, which results in limited development of efficient ionic channels. However, when doubling the IEC of pQAPSF to 2.04 mmol g−1, the conductivity can be increased to 75.1 mS cm−1 at 80 °C, and the hydrophobic network restrains the swelling of pQAPSF effectively (swelling degree is 25.0% at 80 °C). These materials with obvious phase separation showed good chemical stabilities, and can be considered competitive candidates for application in fuel cells.

Anion-exchange membranes (AEM) containing saturated-heterocyclic benzyl-quaternary ammonium (QA) groups synthesised by radiation-grafting onto poly(ethylene-co-tetrafluoroethylene) (ETFE) films are reported. The relative properties of these AEMs are compared with the benchmark radiation-grafted ETFE-g-poly(vinylbenzyltrimethylammonium) AEM. Two AEMs containing heterocyclic-QA head groups were down-selected with higher relative stabilities in aqueous KOH (1 mol dm−3) at 80 °C (compared to the benchmark): these 100 μm thick (fully hydrated) ETFE-g-poly(vinylbenzyl-N-methylpiperidinium)- and ETFE-g-poly(vinylbenzyl-N-methylpyrrolidinium)-based AEMs had as-synthesised ion-exchange capacities (IEC) of 1.64 and 1.66 mmol g−1, respectively, which reduced to 1.36 mmol dm−3 (ca. 17–18% loss of IEC) after alkali ageing (the benchmark AEM showed 30% loss of IEC under the same conditions). These down-selected AEMs exhibited as-synthesised Cl− ion conductivities of 49 and 52 mS cm−1, respectively, at 90 °C in a 95% relative humidity atmosphere, while the OH− forms exhibited conductivities of 138 and 159 mS cm−1, respectively, at 80 °C in a 95% relative humidity atmosphere. The ETFE-g-poly(vinylbenzyl-N-methylpyrrolidinium)-based AEM produced the highest performances when tested as catalyst coated membranes in H2/O2 alkaline polymer electrolyte fuel cells at 60 °C with PtRu/C anodes, Pt/C cathodes, and a polysulfone ionomer: the 100 μm thick variant (synthesised from 50 μm thick ETFE) yielded peak power densities of 800 and 630 mW cm−2 (with and without 0.1 MPa back pressurisation, respectively), while a 52 μm thick variant (synthesised from 25 μm thick ETFE) yielded 980 and 800 mW cm−2 under the same conditions. From these results, we make the recommendation that developers of AEMs, especially pendent benzyl-QA types, should consider the benzyl-N-methylpyrrolidinium head-group as an improvement to the current de facto benchmark benzyltrimethylammonium head-group.

a sustainable iron (fe), nitrogen (n) co-doped high performance fe-n-x/c electrocatalyst for oxygen reduction reaction (orr) is synthesized simply based on nitric acid oxidation of cheap carbon black. the obtained optimal nonprecious metal electrocatalyst shows high orr performance in both alkaline and acidic conditions and possesses appreciable performance/price ratio due to its low cost. furthermore, the structure-activity relationship of different active sites on fe-n-x/c is revealed systematically: fe-n-4/2-c > fe-4-n-c > n-c >> fe-4-c

Alkaline polymer electrolyte fuel cells (APEFCs) have a distinct merit of using nonprecious catalysts and thus attract tremendous research interest in the past decade. Current R&Ds of APEFCs have been focusing on the material stability and cell management. A particularly challenging problem is the water flooding in the anode, where large amounts of water are produced and cause a huge mass transport resistance to H2. Here we report a new strategy to address this problem. By applying a fluorine-containing ionomer (QAPAF), the hydrophobicity of the anode can be natively enhanced, and water flooding is no longer observed, which leads to a big gain in cell voltage up to 140 mV, in comparison to the cell with traditionally hydrophilic anode. With such improvements, the H2 gas can even be fed without humidification (0% RH), and the emission of the anode can also be completely sealed (dead-ended anode). In-situ electrochemical impedance spectroscopy (EIS) finds that even using dry H2, hydrophobic ionomer is beneficial to the water management and the cell performance. This work is a step towards the practical and economic APEFC technology.

Amorphous photonic structures (APSs) with non-iridescent, non-fading, vivid structural colors have attracted great attention in several fields. Tremendous efforts have been dedicated to developing the effective and low-cost approaches for APSs with full-color displays. Resulting from the isotropic photonic pseudogap, APSs have non-iridescent structural colors. We demonstrate that incorporating F e 3 O 4 @ Si O 2 black nanoparticles into the interspace of the periodically arranged Si O 2 white nanospheres can synthesize APSs with different colors. The addition of F e 3 O 4 @ Si O 2 black nanoparticles can enhance the saturation of the non-iridescent structural colors of the APSs by reducing the incoherent scattering in the visible spectrum. In this case, different non-iridescent colors originate from the different diameters of the Si O 2 white nanospheres, and we obtained red, orange, yellow, green, and purple APSs with high reflective index successfully. The APSs with different colors may have potential applications in coatings, cosmetics, textiles, and displays. Moreover, as we use F e 3 O 4 @ Si O 2 as the additive, APSs can be recycled through its magnetic property.

Supporting materials have a significant impact on heterogeneous molecular catalysts. Herein, we have studied the electrochemical CO2 reduction on cobalt phthalocyanine (CoPc) with Vulcan XC-72 and carbon nanotubes (CNTs) supports, respectively. Compared with pure CoPc, the resulting CoPc/XC-72 and CoPc/CNTs exhibits a notable improvement in catalytic activity. The CoPc/XC-72 maintains a stable polarization just for 15 h with a turnover number (TON) of 48,600, whereas the CoPc/CNTs lasts over 45 h with a high TON of 180,000 and CO Faraday efficiency of 88%. The excellent catalytic stability of CoPc/CNTs is attributed to a strong π-π interaction between CoPc and CNTs.

Floquet Majorana edge modes capture the topological features of periodically driven p-wave superconductors. We present a Kitaev chain with multiple time periodic driving terms. Our results demonstrate how multiple driving will affect Floquet bands in frequency space, leading to more robust Floquet Majorana edge modes against driving frequency ω in comparison with the single driving scenario. Meanwhile, we have proposed how to predict Majorana edge modes via the Zak phase of Floquet bands. Besides, in contrast to the cases with single driving term, where the constant phase can be gauged out by properly choosing the initial time, we have shown the relative phase between multiple driving can not be gauged out and will play a dominant role in deciding topological phase transitions. For the sake of completeness, we also investigate the high frequency limit. Analytical results on effective Hamiltonian can be obtained via Magnus expansion and relative phase induced topological transitions can be shown explicitly.

Hydrogen oxidation reaction (HOR), as the anode reaction in alkaline polymer electrolyte fuel cells (APEFCs), is kinetically much more sluggish than that in the proton exchange membrane fuel cell (PEMFC). Therefore, developing efficient non-platinum or even non-noble metal HOR electro-catalysts is of great significance. Herein, the carbon support (Meso C) with mesoporous ravine-like channel and corresponding Ru-loaded catalyst (Ru/Meso C) is deliberately designed to explore the effect of porous microstructure on the HOR electro-catalysis. Both the electrochemical and fuel cell tests manifests that the Ru/Meso C achieves a superior electro-catalytic performance toward the HOR with a peak power density of 1.02 W cm−2. The Cu-UPD and CO-stripping methods are creatively coupled to probe the underlying mechanism of Ru/Meso C. It is proposed that the holey microstructure is relatively hydrophobic to favor H2 access, and the mesoporous channel can provide a confined environment to protect the Ru NPs from oxidation, both facilitating the adsorption and dissociation of H2 and synergistically boosting the HOR. Therefore, to engineer porous microstructure is proved to be a feasible pathway to design efficient HOR electro-catalysts. Meanwhile, the electrochemical techniques (Cu-UPD & CO-stripping) may act as a potential tool to probe the hydrophilic-hydrophobic properties.

In order to achieve a better trade-off among ionic conductivity, mechanical strength and chemical stability, a series of novel aggregated and ionic cross-linked anion exchange membranes (AEMs) are recommended, namely, acS6QAPSF, acS8QAPSF and acS10QAPSF. Cross-linked network shoulders the responsibility to toughen the acSxQAPSF. Appropriate micro-morphology is responsible for facilitating the conduction of OH− and improving the alkaline stability of the acSxQAPSF. Compared with the original QAPSF, acSxQAPSF membranes exhibit much better properties. Specifically, for acS8QAPSF, a high OH− conductivity of 90.5 mS cm−1 is achieved at 80 °C, with the swelling degree of 10.0%. The tensile strength and elongation at break of wet acS8QAPSF at 25 °C are 23.9 Mpa and 21.1%, respectively. After testing in 1 M NaOH at 80 °C for 30 days, the weight loss of acS8QAPSF is 8.0%, with the losses of tensile strength and elongation at break of 13.8% and 13.3%, respectively. Its IEC and IC retentions are 92.0% and 90.5%, respectively. For acS8QAPSF, a fuel cell peak power density of 0.612 W cm−2 is obtained at 60 °C. While for QAPSF, its fuel cell peak power density is only 0.101 W cm−2, and the film is cracked after the 30 days stability test.

A novel magnetic drug-loaded osteoinductive Fe3O4/CaCO3 hybrid microspheres system (MDHMs) with excellent drug delivery property has been fabricated by a modified coprecipitation method. The MDHMs are uniform vaterite microspheres with well-defined mesoporous nanostructures. The formation of vaterite is based on the templating effect of casein micelles, which is promising in bone tissue engineering. Cyclodextrins (CDs) increase the porosity of the microspheres with a pore size of about 7.3 nm and a surface area of about 50.73 m2 g−1. The mesoporous structure gives the MDHMs great drug loading efficiency of about 80.75–88.74% and the minocycline-loaded MDHMs display a sustained drug release property (about 95% in 5 d). Moreover, the MDHMs also possess stable magnetic property with a saturation magnetization of about 4.41 emu g−1 and a remarkable magnetism-responsive behavior. These results demonstrate that with superior drug delivery property, osteoinductive potential and magnetic property, the MDHMs have a great potential in the treatment of peri-implantitis.

The hybrid optical pumping spin exchange relaxation free (HOPSERF) atomic co-magnetometers make ultrahigh sensitivity measurement of inertia achievable. The wall relaxation rate has a big effect on the polarization and fundamental sensitivity for the co-magnetometer, but it is often neglected in the experiments. However, there is almost no work about the systematic analysis of the influence factors on the polarization and the fundamental sensitivity of the HOPSERF co-magnetometers. Here we systematically study the polarization and the fundamental sensitivity of 39K–85Rb–21Ne and 133Cs–85Rb–21Ne HOPSERF co-magnetometers with low polarization limit and the wall relaxation rate. The 21Ne number density, the power density and wavelength of pump beam will affect the polarization greatly by affecting the pumping rate of the pump beam. We obtain a general formula on the fundamental sensitivity of the HOPSERF co-magnetometers due to shot-noise and the fundamental sensitivity changes with multiple systemic parameters, where the suitable number density of buffer gas and quench gas make the fundamental sensitivity highest. The fundamental sensitivity 7.5355×10–11 rad·s–1·Hz–1/2 of 133Cs–85Rb–21Ne co-magnetometer is higher than the ultimate theoretical sensitivity 2×10–10 rad·s–1·Hz–1/2 of K–21Ne co-magnetometer.

Recent discoveries of dynamic ice VII and superionic ice highlight the importance of ionic diffusions in discriminating high-pressure (P) water phases. The rare event nature and the chemical bond breaking associated with these diffusions, however, make extensive simulations of these processes unpractical to ab initio and inappropriate for force field based methods. Using a first-principles neural network potential, we performed a theoretical study of water at 5–70 GPa and 300–3000 K. Long-time dynamics of protons and oxygens were found indispensable in discriminating several subtle states of water, characterized by proton’s and oxygen ion’s diffusion coefficients and the distribution of proton’s displacements. Within dynamic ice VII, two types of proton transfer mechanisms, i.e., translational and rotational transfers, were identified to discriminate this region further into dynamic ice VII T and dynamic ice VII R. The triple point between ice VII, superionic ice (SI), and liquid exists because the loosening of the bcc oxygen skeleton is prevented by the decrease of interatomic distances at high P’s. The melting of ice VII above ∼40 GPa can be understood as a process of two individual steps: the melting of protons and the retarded melting of oxygens, responsible for the forming of SI. The boundary of the dynamic ice VII and SI lies on the continuation line ice VII’s melting curve at low P’s. Based on these, a detailed phase diagram is given, which may shed light on studies of water under P’s in a wide range of interdisciplinary sciences.

We investigate topological supersolidity of dipolar Fermi gases in a spin-dependent 2D optical lattice. Numerical results show that the topological supersolid states can be synthesized via the combination of topological superfluid states with the stripe order, where the topological superfluid states generated with dipolar interaction possess the $\Delta_{x}+i\Delta_{y}$ order, and it is of D class topological classification. By adjusting the ratio between hopping amplitude $t_{x}/t_{y}$ and interaction strength $U$ with dipole orientation $\phi \approx \frac{\pi}{4}$, the system will undergo phase transitions among the $p_{x}+ip_{y}$-wave topological superfluid state, the p-wave superfluid state, and the topological supersolid state. The topological supersolid state is proved to be stable by the positive sign of the inverse compressibility. We design an experimental protocol to realize the staggered next-next-nearest-neighbour hopping via the laser assisted tunneling technique, which is the key to synthesize topological supersolid states., Comment: 5 pages with 6 figures

ispartof: Acs Sustainable Chemistry & Engineering vol:8 issue:1 pages:1-1 status: published

In this work, we explore the possibility of using MnCO3 as active material for alkaline rechargeable batteries. K2CO3 solution is chosen as electrolyte because the solubility of MnCO3 in K2CO3 electrolyte keeps lower than that in KOH electrolyte of the same pH values, which may promote the cyclability of MnCO3. XRD and XPS measurements reveal a two-electron transfer reaction during cycling, corresponding to the conversion of MnCO3/MnO2. Further investigations demonstrate the MnCO3 electrode can be cycled 50 cycles without obvious capacity decay and the coulombic efficiency keeps over 95.0% after the 8th cycle. The present study provides a new perspective in searching new electrode materials and electrolyte systems for alkaline rechargeable batteries.

To meet the requirements of potential applications, it is of great importance to explore new catalysts for formic acid oxidation that have both ultra-high mass activity and CO resistance. Here, we successfully synthesize atomically dispersed Rh on N-doped carbon (SA-Rh/CN) and discover that SA-Rh/CN exhibits promising electrocatalytic properties for formic acid oxidation. The mass activity shows 28- and 67-fold enhancements compared with state-of-the-art Pd/C and Pt/C, respectively, despite the low activity of Rh/C. Interestingly, SA-Rh/CN exhibits greatly enhanced tolerance to CO poisoning, and Rh atoms in SA-Rh/CN resist sintering after long-term testing, resulting in excellent catalytic stability. Density functional theory calculations suggest that the formate route is more favourable on SA-Rh/CN. According to calculations, the high barrier to produce CO, together with the relatively unfavourable binding with CO, contribute to its CO tolerance.

The Pt-catalyzed hydrogen oxidation reaction (HOR) for alkaline polymer electrolyte fuel cells (APEFCs) has been one of the focus subjects in current fuel-cell research. The Pt catalyst is inferior for HOR in alkaline solutions, and alloying with Ru is an effective promotion strategy. APEFCs with Pt-Ru anodes have provided a performance benchmark over 1 W cm-2 at 60 °C. The Pt anode is now found to be in fact as good as the Pt-Ru anode for APEFCs operated at elevated conditions. At 80 °C with appropriate gas back-pressure, the cell with a Pt anode exhibits a peak power density of about 1.9 W cm-2 , which is very close to that with a Pt-Ru anode. Even by decreasing the anode Pt loading to 0.1 mg cm-2 , over 1.5 W cm-2 can still be achieved at 80 °C. This finding alters the previous understanding about the Pt catalyzed HOR in alkaline media and casts a new light on the development of practical and high-power APFEC technology.

Aim To evaluate the diagnostic value of B-scan ultrasound and explore the cytological characteristics of patients with vitreoretinal lymphoma (VRL) and primary central nervous system lymphoma (PCNSL). Methods The clinical data and pathologic specimens from patients with VRL diagnosed at the North Huashan Hospital from 2016 to 2017 were retrospectively reviewed. The patients were diagnosed by slit lamp ophthalmoscopy, B-scan ultrasound, cytology of the vitreous, which was obtained by vitrectomy, and cytokine measurements of interleukin (IL)-10 and IL-6. Results Twenty-six eyes (19.4%) out of 134 eyes of 67 patients (47 men and 20 women) with PCNSL were diagnosed with VRL by B-scan ultrasound, and 14 eyes (10.4%) were diagnosed by slit lamp ophthalmoscopy. Twenty-four eyes (17.9%) of 17 patients were confirmed as having VRL with cytology. No difference in the association between intracranial lesion location and ocular involvement was found. VRL patients had higher levels of vitreous IL-10 and IL-10/IL-6 when compared with macular hole cases, but the difference was not statistically significant. Conclusion A total of 25.4% of the PCNSL patients had VRL, B-scan ultrasound examination had characteristic features and is recommended over slit lamp ophthalmoscopy for the screening diagnosis of PCNSL with intraocular involvement. Moreover, the cytological and immunohistochemical analyses performed after 25-gauge diagnostic vitrectomy were accurate diagnostic techniques.

The aim of the present study was to prospectively evaluate the recurrence and survival outcome of primary central nervous system lymphoma (PCNSL) with intraocular involvement. For this purpose, a prospective cohort of 103 pathologically confirmed patients with PCNSL was enrolled in this study. Ophthalmologic examinations were performed both at diagnosis and during follow‑up. The patients with PCNSL with suspected intraocular involvement underwent vitrectomy for confirmation. Patients who presented with intraocular involvement either at diagnosis or during disease progression were allocated to the intraocular lymphoma (IOL) group. All patients with PCNSL received systemic methotrexate (MTX)‑based chemotherapy with or without radiotherapy. MTX intravitreal injection combined with systemic MTX‑based chemotherapy was recommended once ocular lesions were confirmed. Recurrent intraocular and central nervous system (CNS) events, progression‑free survival (PFS) and overall survival (OS) outcomes were analyzed. The findings of this study revealed that 21 patients with PCNSL exhibited intraocular involvement. One patient with IOL presented with isolated ocular lymphoma at the initial diagnosis, and the others presented with ocular involvement along with CNS invasion during the course of the disease. A total of 14 patients received systemic MTX‑based chemotherapy prior to the diagnosis of IOL. The recurrence rates in patients with or without intraocular involvement were 71.4 and 46.3%, respectively (P=0.04) and the relapse sites in the patients with IOL included the brain (3 patients), eyes (6 patients), and both brain and eyes (6 cases). The median PFS was 13 months in the IOL group and 19 months in the patients without intraocular involvement (non‑IOL) (P=0.019). The median OS was 51 months vs. 56 months, respectively (P=0.312). There was no significant difference in the 2‑year PFS and OS rates between the 2 groups (23.8% vs. 23.2%, P=0.951; and 61.9% vs. 41.4%, P=0.093, respectively). On the whole, the findings of this study suggest that patients with IOL have a high risk of relapse and a poor PFS compared to patients without IOL, but a similar OS.

Monodisperse colloidal particles have promising applications in electrophoretic displays with vivid colors, reversibility and low switching times. In this study, a facile, effective and large-scale strategy for preparing size-controlled Fe

Background Certified nursing assistants (CNAs) in palliative care units often encounter the death of patients and undergo emotional burdens because of their altruistic practices. However, the influences of altruism and perceptions of death on the work morale of CNAs remain unclear. The fact that morale can be improved by modifying related factors justifies the necessity of a theoretical model of morale for CNAs. However, such a model is currently absent. Based on relevant literature, factors including altruism, social support, perceptions of death, and job satisfaction are related to morale through the mediation of job stress. Aim This study was aimed toward determining the influencing factors and developing a structural model of morale with regard to CNAs working in palliative care units. Design The hypothesized model was tested in a cross-sectional design with structural equation modeling using AMOS 23. Setting/participants A total of 413 CNAs from five hospice units in Taiwan participated in the survey. Results Goodness-of-fit indexes, including χ2/DF = 2.187, PGFI = 0.461, and PNFI = 0.462, among others, confirmed the modified model fit the data well. Altruism, social support, perceptions of death, and job satisfaction were negatively related to job stress (-0.238, -0.196, -0.204, and -0.131, respectively). Altruism and social support positively affected job satisfaction (0.635 and 0.553). Factors directly affecting morale included altruism, social support, job stress, and job satisfaction (0.837, 0.711, -0.244, and 0.540, respectively). The relationship between altruism and morale was the strongest among all the direct paths toward morale. Job stress was the major mediator in these relationships. Conclusion Altruism is imperative for morale. The confirmed model is called the Five Constructs to Morale (5CM) model. These findings indicate the need to assess the levels of altruism and perceptions of death during the recruitment of CNAs. From the perspective of human resource management and organizational behavior, CNAs with a high level of altruism and a positive attitude toward death assure the well-being of end of life patients because of work involvement and commitment to the challenging work of hospice care. The cultivation of a supportive environment and coping strategies are suggested for the management of CNAs facing patient death. Hospice care decision makers should carefully assess morale levels among health professionals by applying the 5CM model. Identifying modifiable factors that can improve morale among nursing staff in hospice care to ensure work fulfillment and quality care merits emphasis in clinical practice. The establishment of effective strategies to facilitate the work morale of nursing staff is suggested for palliative care units. Morale improvement related task should be a global public health priority.

The mechanism of hydrogen oxidation reaction (HOR) in alkaline media is still under debate. In this work, we have systemically examined the HOR performance on planar Pt electrodes modified with ten different kinds of metal hydroxides/oxides (metal = Mg, Cr, Mn, Fe, Co, Ni, Cu, Ru, La and Ce). The HOR exchange current density (i0) increases monotonically with higher electrode’s oxophilicity, which is determined by the current densities of CO stripping at 0.4 V vs. RHE (iCO@0.4 V). However, the Ru modification exhibits a clear deviation from the monotonic relation and it demonstrates a superior catalytic activity towards HOR, relative to other metal modifications. This unexpected result is ascribed to the reduction in hydrogen binding energy (HBE) owing to the modification of metallic Ru rather than its corresponding hydroxide or oxide. The present study indicates that the electronic effect and the oxophilic effect co-exist in the HOR on Pt-based catalysts in alkaline media, but the former one is of more significance.

The properties of high temperature polymer electrolyte membranes (HT-PEMs) are determined directly by the polymer matrix with phosphoric acid (PA) doping. Here, new polymer materials based on poly (arylene piperidine)s (PAPs) are prepared by one-step polymerization as PA absorbing matrix for HT-PEM fuel cells (HT-PEMFCs) application. The PAPs show excellent thermal stability and high glass transition temperature. Among PAPs, PA doped poly (N-methyl-piperidine-co-p-terphenyl) (PPT/PA) shows a high proton conductivity of 96.0 mS cm−1 at 180 °C without humidification and an excellent tensile strength of 12 MPa, which is much better than that of PA doped commercial poly [2,2’-(p-oxydiphenylene)-5,5′-benzimidazole] (OPBI/PA). The enhancement on conductivity of PPT/PA is attributed to the formation of micro-phase separation. A single cell based on PPT/PA membrane presents outstanding performance with a maximum power density of 1220.2 mW cm−2 with H2/O2 feeding under 0.15 MPa backpressure in cathode at 180 °C, which is 1.85 times of that with OPBI/PA membrane (660.8 mW cm−2). Furthermore, a H2/air single cell with PPT/PA shows excellent stability at a constant current density of 120 mAcm−2 and 150 °C for 1600 h. This work indicates PAPs (especially, PPT) are a promising PA doping polymer matrix for high temperature polymer electrolyte membrane fuel cells application.

Transition metal dichalcogenides (TMDs) are promising for spintronic devices owing to their spin-orbit coupling and loss of inversion symmetry. However, further development was obstructed by their intrinsic nonmagnetic property. Doping TMDs with non-metal light atoms has been predicted to be a good option to induce unexpected magnetic properties which remain rarely explored. Here, we utilize nitrogen doping to introduce magnetic domains into anisotropic ReS2, giving rise to a transition from nonmagnetic to tunable magnetic ordering. Both of the experimental and computational results confirmed that the N-doping in ReS2 prefers to take place at the edge site than in-plane site. With controlled doping concentration, it exhibits a unique ferromagnetic-antiferromagnetic (FM-AFM) coupling. Assisted by theoretical calculations, we demonstrated that FM-AFM coupling presents a strong link to doping contents and doping sites. Wherein, the FM ordering mostly comes from N atoms and the AFM ordering originate from Re atoms. At the N-doping content of 4.24%, the saturated magnetization of N-doped ReS2 reached the largest value of 2.1 emu g−1 at 2 K. Further altering the content to 6.64%, the saturated magnetization of N-doped ReS2 decreases, but exhibits a distinct exchange bias (EB) phenomenon of around 200 Oe. With controlled N-doping concentrations, the intrinsic spin in ReS2 could be well altered and resulted in distinct magnetism, presenting tremendous potential for spintronic devices in information storage. A transition from non-magnetic to magnetic ordering can be induced in ReS2 by means of non-metal doping. At team led by Lei Fu at Wuhan University performed a combined experimental and computational investigation aimed at shedding light to the interplay between N doping and the onset of magnetic ordering in anisotropic ReS2. N doping was found to preferentially occur at the edge sites rather than within the plane, and a controlled doping concentration gave rise to a ferromagnetic-antiferromagnetic coupling. Notably, increasing the N content to 4.24 % resulted in a large value of saturated magnetization up to 2.1 emu g−1 at 2 K, and while a further increase to 6.64% led to the suppression of saturated magnetization, it resulted in the onset of an exchange bias of 200 Oe.

Two enantiomeric pairs of new 3d-4f heterometallic clusters have been built from two enantiomer Schiff base derivatives, labeled as R-/ S-H

Background Macrophages in the tumor microenvironment play a critical role in tumorigenesis and anti-cancer drug resistance. Burkitt’s lymphoma (BL) is a B-cell non-Hodgkin’s lymphoma with dense macrophage infiltration. However, the role for macrophages in BL remains largely unknown. Methods B7-H1, a transmembrane glycoprotein in the B7 family, suppresses T cell activation and proliferation and induces the apoptosis of activated T cells. The expression of B7-H1 in BL clinical tissues was determined by streptavidin-peroxidase immunohistochemistry. The mutual regulation between macrophages and BL Raji cells was investigated in a co-culture system. The cell proliferation and cell cycle distribution of Raji cells were determined using BrdU staining coupled with flow cytometry. CD163, CD204 and B7-H1 expression was assessed by flow cytometry and Western blot. Cell invasion was analyzed by Transwell assay. The expression of cytokines was detected by quantitative RT-PCR. Immunofluorescence and allogeneic T-cell proliferation assays were used to compare the expression of B7-H1, p-STAT6, or p-STAT3 and CD3+ T cell proliferation treated with or without amphotericin B. Results B7-H1 was highly expressed in tumor infiltration macrophages in most clinical BL tissues. In vitro, Raji cells synthesized IL-4, IL-6, IL-10 and IL-13 to induce CD163, CD204 and B7-H1 expression in co-cultured macrophages, which in turn promoted Raji cell proliferation and invasion. Interestingly, antifungal agent amphotericin B not only inhibited STAT6 phosphorylation to suppress the M2 polarization of macrophages, but also promoted CD3+ T cell proliferation by regulating B7-H1 protein expression in macrophages. Conclusion Amphotericin B might represent a novel immunotherapeutic approach to treat patients with BL. Electronic supplementary material The online version of this article (10.1186/s12885-018-4266-0) contains supplementary material, which is available to authorized users.

We report topological nonlinear optics with spin-orbit coupled Bose-Einstein condensate in a cavity. The cavity is driven by a pump laser and weak probe laser which excite Bose-Einstein condensate to an intermediate storage level, where the standard Raman process engineers spin-orbit coupling. We show that the nonlinear photonic interactions at the transitional pathways of dressed states result in new type of optical transparencies, which get completely inverted with atom induced gain. These nonlinear interactions also implant topological sort of features in probe transmission modes by inducing gapless Dirac-like cones, which become gaped in presence of Raman detuning. The topological features get interestingly enhanced in gain regime where the gapless topological edge-like states emerge among the probe modes, which can cause non-trivial phase transition. We show that spin-orbit coupling and Zeeman field effects also impressively revamp fast and slow probe light. The manipulation of dressed states for quantum nonlinear optics with topological characteristics in our findings could be a crucial step towards topological quantum computation., 10 pages, 9 figures

Background The VicRK two-component signalling system regulates virulence and cariogenicity in Streptococcus mutans (S. mutans). The purpose of this study was to explore the genetic polymorphisms of the vicR and vicK genes, which are associated with dental caries in children with S. mutans. Methods In this study, 121 (from each group) clinical S. mutans strains were isolated from caries-free children and children with high-severity caries to sequence the vicR and vicK genes. Genomic DNA was extracted from S. mutans strains and amplified using PCR. The PCR products were purified and sequenced. A chi-squared test and ABI Variant Reporter software were used to analyse the sequencing results. Results The 242 clinically isolated S. mutans strains contained the full-length vicR and vicK genes. No nucleotide sequence insertions or deletions were observed in the two genes. Four silent point mutations were identified in the vicR genes, and no missense mutations could be detected. Forty-one mutations were identified in the vicK genes. In addition to 32 silent mutations, 9 missense mutations at the 173, 337, 470, 1051, 1132, 1258, 1260, 1277, and 1348 bp positions were found. The distribution frequencies of the missense mutations were not significantly different between the groups, except for the C470T mutation. The frequency of the C470T missense mutation was higher in the high-severity caries group than in the caries-free group. Conclusions vicR sequences are highly conserved in S. mutans clinical isolates. The locus 470 missense mutation of the vicK gene may be related to caries in children with S. mutans.

Magnetic cooling is a highly efficient refrigeration technique with the potential of replacing expensive and rare helium-3 in the field of ultra-low temperature cooling. However, the visualization of a cryogen at an extremely low temperature and in a strong magnetic field is challenging, but it is crucial for the precise positioning and in situ thermal probe measurements in potential practical applications. Here, the activation of a red-emissive Mn(ii) ion using 3d/4f chemistry produces a luminescent molecule cooler, [Gd5Mn2(LOMe)2(OH)4(Ac)6(MeOH)10Cl2]Cl3·2MeOH (1), with the core of an Mn(ii)-anchored heptanuclear [GdIII5MnII2] pyramid. The photoluminescence (PL) of the Mn2+ emission, with a large Stokes shift (λem ∼ 690 nm) from 4T1(4G) → 6A1(6S), shows not only a sensitive temperature sensing property but also reversible mechanoluminescence (ML). More attractively, these findings reveal a considerable magnetocaloric effect (MCE) coupled with a tunable emission window, opening up new opportunities in the multifunctional applications of PL, ML, and the MCE involving red-light sources, thermometers, and stress imaging. In particular, this provides a novel resolution to design visualized PL coolers.