A Pullulan polysaccharide-based flame-retardant polyelectrolyte hydrogel for high-safety flexible zinc ion capacitors.

Potential safety hazards such as leakage, flammability and thermal runaway of liquid electrolytes in conventional energy storage devices have seriously hindered their further development. In this work, a flame-retardant polyacrylamide/pullulan/phytic acid (PAM/PUL/PA) hydrogel electrolyte is prepared by using PA as flame-retardant additive, PAM as main polymer chain by one-step radical polymerization method. The PAM/PUL/PA hydrogel shows good flame-retardant properties with limiting oxygen index of up to 58 %, high mechanical performance with stretch up to 1535 % and 92 kPa tensile stress.

Fine nanostructure design of metal chalcogenide conversion-based cathode materials for rechargeable magnesium batteries.

Magnesium-ion batteries (MIBs) a strong candidate to set off the second-generation energy storage boom due to their double charge transfer and dendrite-free advantages. However, the strong coulombic force and the huge diffusion energy barrier between Mg and the electrode material have led to need for a cathode material that can enable the rapid and reversible de-insertion of Mg. So far, researchers have found that the sulfur-converted cathode materials have a greater application prospect due to the advantages of low price and high specific capacity, etc.

Multifunctional Zincophilic Hydrogel Electrolyte with Abundant Hydrogen Bonds for Zinc-Ion Capacitors and Supercapacitors.

The new-generation flexible Zn-ion capacitors (ZICs) require multifunctionality and environmental adaptability for practical applications. This essentially means that hydrogel electrolytes are expected to possess superior mechanical properties, temperature resistance, and tunable interface properties to resist flexibility loss and performance degradation over a wide operating temperatures range. Herein, a multifunctional polyzwitterionic hydrogel electrolyte (PAM/LA/PSBMA) with wide operating temperatures, excellent tensile ability, high water retention, and self-adhesion is designed.

Covalent Organic Frameworks as Electrode Materials for Alkali Metal-ion Batteries.

Covalent organic frameworks (COFs) are a class of porous crystalline polymeric materials constructed by linking organic small molecules through covalent bonds. COFs have the advantages of strong covalent bond network, adjustable pore structure, large specific surface area and excellent thermal stability, and have broad application prospects in various fields. Based on these advantages, rational COFs design strategies such as the introduction of active sites, construction of conjugated structures, and carbon material composite, etc.

Title High Solar-Thermal Conversion Aerogel for Efficient Atmospheric Water Harvesting.

The shortage of freshwater is a global problem, however, the gel that can be used for atmospheric water harvesting (AWH) in recent years studying, suffer from salt leakage, agglomeration, and slow water evaporation efficiency. Herein, a solar-driven atmospheric water harvesting (SAWH) aerogel is prepared by UV polymerization and freeze-drying technique, using poly(N-isopropylacrylamide) (PNIPAm), hydroxypropyl cellulose (HPC), ethanolamine-decorate LiCl (E-LiCl) and polyaniline (PANI) as raw materials. The PNIPAm and HPC formed aerogel networks makes the E-LiCl stably and efficiently loaded, improving the water adsorption-desorption kinetics, and PANI achieves rapid water vapor evaporation.

Generation of 978 nm dispersion-managed solitons from a polarization-maintaining Yb-doped figure-of-9 fiber laser.

Restricted by the narrow gain bandwidth of Yb near 980 nm, it is challenging to generate dispersion-managed (DM) solitons at this wavelength. In this work, we demonstrate the generation of DM solitons at 978 nm in a polarization-maintaining (PM) figure-of-9 fiber laser. Highly coherent pulses with 14.

Generation of 1.3 µm femtosecond pulses by cascaded nonlinear optical gain modulation in phosphosilicate fiber.

Nonlinear optical gain modulation (NOGM) is a simple and effective approach to generate highly coherent ultrafast pulses with a flexible wavelength. In this work, we demonstrate 34 nJ, 170 fs pulse generation at 1319 nm through a piece of phosphorus-doped fiber by two-stage cascaded NOGM with a 1064 nm pulsed pump. Beyond the experiment, numerical results show that 668 nJ, 391 fs pulses at 1.

Efficient single-frequency 972 nm Yb-doped fiber amplifier with core pumping and elevated temperature.

In this work, we present a monolithic single-frequency, single-mode and polarization maintaining Yb-doped fiber (YDF) amplifier delivering up to 6.9 W at 972 nm with a high efficiency of 53.6%.

Alleviating Zn Dendrites by Growth of Ultrafine ZnO Nanowire Arrays through Horizontal Anodizing for High-Capacity, Long-Life Zn Ion Capacitors.

Zn ion capacitors (ZICs) composed of a carbon-based cathode and a Zn anode are one of the most promising energy storage devices due to their inherent safety and high-power output. However, their poor cycling stability originating from the Zn dendrites' formation and low energy density limited by insufficient activated carbon properties remain major challenges for development of high-performance ZICs. Hence, we constructed a facile and effective strategy to alleviate "edge effects" and suppress Zn dendrites by growing ZnO nanowire arrays on Zn foil (ZnO@Zn) using a horizontally potentiostatic anodizing technique.

Three-dimensional nanoporous activated carbon electrode derived from acacia wood for high-performance supercapacitor.

Herein, the novel acacia wood based hierarchical porous activated carbons (AWCs) are easily prepared, low cost and have excellent characterization, such as special biomass nanopores structural stability and large specific surface areas. Activating agents such as KOH, ZnCl, and HPO have been used to convert acacia wood carbon into active carbons such as AWC-K, AWC-Z, and AWC-P, respectively, which are named after the activating agent. As a supercapacitor electrode, the AWC-K sample has a high yield was 69.

Numerical simulation of nonlinear optical gain modulation in a Raman fiber amplifier.

Nonlinear optical gain modulation (NOGM) in a Raman fiber amplifier is numerically simulated with the generalized nonlinear Schrödinger equation. In the NOGM setup, a single frequency continuous wave seed laser is gain modulated into femtosecond pulses by an ultrafast pump, which can induce strong stimulated Raman scattering in a piece of single mode optical fiber. Different parameters regarding seed, pump and nonlinear gain medium (Raman fiber) are investigated in detail to find the best condition for higher Raman conversion efficiency.

An asymmetric supercapacitor based on controllable WO nanorod bundle and alfalfa-derived porous carbon.

A novel asymmetric supercapacitor (ASC) is assembled on the basis of an inerratic hexagonal-like WO nanorod bundle as a negative electrode and graphene-like alfalfa-derived porous activated carbon (APAC) as the positive electrode in 1 M HSO aqueous electrolyte. The WO nanostructures prepared at pH of 1.6, 1.

Robust single-frequency 589 nm fiber laser based on phase modulation and passive demodulation.

A robust 20-W continuous-wave single frequency 589 nm laser is developed to aim for sodium guide star in astronomy. The source is based on applying π-depth binary phase modulation to a single frequency seed laser along with 3 steps of strain in the gain fiber to suppress the stimulated Brillouin scattering in the high power 1178 nm amplifier and realizing the recovery of single frequency after frequency doubling in a periodically poled LiTaO crystal. The efficiency of frequency doubling reaches up to 41.

Cascaded nonlinear optical gain modulation for coherent femtosecond pulse generation.

Nonlinear optical gain modulation (NOGM) is a method to generate high performance ultrafast pulses with wavelength versatility. Here we demonstrate coherent femtosecond Raman pulse generation through cascaded NOGM process experimentally. Two single-frequency seed lasers (1121 and 1178 nm) are gain-modulated by 117 nJ 1064 nm picosecond pulses in a Raman fiber amplifier.

Spectral compression by phase doubling in second harmonic generation.

In second harmonic generation, the phase of the optical field is doubled, which has important implications. Here, the phase-doubling effect is utilized to solve a long-standing challenge in the power scaling of single-frequency laser. (-π/2, π/2) binary phase modulation is applied to a single-frequency seed laser to broaden the spectrum and suppress the stimulated Brillouin scattering in a high-power fiber amplifier.

Spectral and RIN properties of a single-frequency Raman fiber amplifier co-pumped by ASE source.

Spectral and relative intensity noise (RIN) characteristics of a single-frequency Raman fiber amplifier co-pumped by amplified spontaneous emission (ASE) sources are investigated experimentally. Due to the relatively lower intensity noise of ASE sources compared to usual fiber laser pumps, the full width at half maximum (FWHM) linewidth of the signal laser increases negligibly. But there is significant increase in RIN and spectral wings due to the noise transfer at high frequency from the ASE source during the Raman amplification.

Synthesis of porous carbon material based on biomass derived from hibiscus sabdariffa fruits as active electrodes for high-performance symmetric supercapacitors.

Carbon-based materials are manufactured as high-performance electrodes using biomass waste in the renewable energy storage field. Herein, four types of hierarchical porous activated carbon using hibiscus sabdariffa fruits (HBFs) as a low-cost biomass precursor are synthesized through carbonization and activation. NHCl is used as a chemical blowing agent to form carbon nanosheets, which are the first types of hibiscus sabdariffa fruit-based carbon (HBFC-1) sample, and KOH also forms a significant bond in the activation process.

Resonant frequency doubling of phase-modulation-generated few-frequency fiber laser.

Resonant frequency doubling of periodically phase-modulated single-frequency fiber laser is investigated as a method for power scaling of visible fiber lasers. Sinusoidal phase modulation is applied to generate few-frequency lasers at 1064 nm in the proof of principle experiments. By adjusting the modulation frequency to match the free spectral range of a doubling cavity, a resonant enhancement condition can be achieved and a near 30 W 532 nm laser is generated with a maximum conversion efficiency above 80%.

Effects of inverse ratio ventilation combined with lung protective ventilation on pulmonary function in patients with severe burns for surgery.

To investigate the effects of inverse ratio ventilation combined with lung-protective ventilation on pulmonary function and inflammatory factors in severe burn patients undergoing surgery. : Eighty patients with severe burns undergoing elective surgery were divided randomly into two groups: control (CG, = 40) and experiment (EG, = 40). The CG had conventional ventilation, whereas the EG were ventilated with tidal volume (TV) of 6-8 ml/kg, I (inspiration): E (expiration) of 2:1, and positive end-expiratory pressure (PEEP) 5 cm H2O.

More than 20 W fiber-based continuous-wave single frequency laser at 780 nm.

We demonstrate a 21.2 W continuous-wave single frequency 780 nm laser by utilizing single-pass frequency doubling of a 49.8 W 1560 nm fiber amplifier in a periodically-poled magnesium-oxide-doped lithium niobate (MgO: PPLN) crystal.

2 W single-frequency, low-noise 509 nm laser via single-pass frequency doubling of an ECDL-seeded Yb fiber amplifier.

A single-frequency low-noise green laser at 509 nm is developed for the study of cesium Rydberg atoms. The laser is generated by single-pass second-harmonic generation of a Yb fiber amplifier seeded with an external cavity diode laser (ECDL) at 1018 nm in a periodically poled MgO-doped lithium-niobate crystal. An up to 2.

High order cascaded Raman random fiber laser with high spectral purity.

An up to 8th order cascaded Raman random fiber laser with high spectral purity is achieved with the pumping of a narrow linewidth amplified spontaneous emission source. The spectral purity is over 90% for all the 8 Stokes orders. The highest output power is 6.

Magnetometry using fluorescence of sodium vapor.

Magnetic resonance of sodium fluorescence is studied with varying laser intensity, duty cycle, and field strength. A magnetometer based on a sodium vapor cell filled with He buffer gas is demonstrated, using a single amplitude-modulated laser beam. With a 589 nm laser tuned at the D or D line, the magnetic field is inferred from the variation of fluorescence.

Sodium guide star laser pulsed at Larmor frequency: erratum.

We correct an improper statement on the geomagnetic field of an astronomical telescope site in our original paper [Opt. Lett.42, 4351 (2017)OPLEDP0146-959210.