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Abstract  The antioxidant properties of hydroxycinnamic acid derivatives (HCA) were studied by laser flash photolysis. The transient species with maximum absorption at 360 nm were assigned to the phenoxyl radical of HCA. The SO4•− induced oxidation of HCA was also investigated. It was shown that the interaction of SO4•− with HCA resulted in the formation of HCA phenoxyl radicals with rate constants of 2.0–3.9×109 M−1 s−1. The reactions of HCA with triplet state of benzophenone were analyzed and quenching rate constants of 4.3–7.8×109 M−1 s−1 were determined. [ABSTRACT FROM AUTHOR]

The numerical algorithm is presented for solving coupled extended nonlinear Schrödinger equations (NLSEs) including higher-order dispersion, retarded nonlinear response, and self-steepening terms. The numerical results show that the influence of the retarded nonlinear response and self-steepening effect on the coupling dynamics in a nonlinear directional coupler (NLDC) is strongly dependent on the input peak power, input pulse width, and product of the dispersion length and the coupling coefficient (LDκ). In the case of LDκ≫1, the pulse coupling obeys Jensen's equation as long as the input pulse width is broader than 250 fs and the coupler is far from zero dispersion. Both the retarded nonlinear response and the self-steepening effect could be ignored if the normalized amplitude of the input pulse is less than 0.5. It was also found that the retarded nonlinear response improves the energy transfer efficiency between the two coupled waveguides. [ABSTRACT FROM PUBLISHER]

Free radical reactions of Martynoside (MAR), a phenylpropanoid glycoside, with a variety of oxidants were studied in the aqueous solution by laser photolysis and pulse radiolysis techniques. The p K a value of MAR in aqueous solution was measured from the pH dependent changes of the UV absorption at 384 nm with value of p K a =9.2. The phenoxyl radical of MAR which exhibits maximum absorption at 360 nm was generated by one-electron transfer to N 3 • or Br 2 •- . Other important properties of phenoxyl radical such as extinction coefficient, formation and decay rate constants were also determined. The reaction rate constant of O 2 •- with MAR, k =8.5×10 4 dm 3 · mol -1 · s -1 , was measured by the method of competition kinetics. By measuring time-resolved luminescence emission at 1270 nm, the quenching rate constant of singlet oxygen by MAR was obtained to be 3.3×10 6 dm 3 · mol -1 · s -1 . Reduction potential of the MAR couple (MAR • /MAR), determined using rutin as reference compound, gave a value E =0.66 V vs. NHE. The antioxidative properties of MAR were compared with those of some well-known antioxidants. [ABSTRACT FROM AUTHOR]

The free radical scavenging activities of puerarin towards nitrogen dioxide radicals (NO), nitric oxide radicals (NO˙) and hydroxyl radicals (OH˙) were investigated by pulse radiolysis. Puerarin reacted with (NO) or (NO˙) to form puerarin-4-O˙ with the absorption maximum at 340 nm, but reacted with OH˙ to form at least three transient species including puerarin-2-O˙, puerarin-4-O˙ and [puerarin-OH]˙with a broad absorption spectrum band (300-750 nm). In addition, the reaction rate constants of puerarin reacting with NO, and NO˙ were determined as 2.6 × 108, 1.7× 108 and 3.9 × 109 L · mol−1 · s−1, respectively. [ABSTRACT FROM AUTHOR]

One-electron oxidation of N-4-desmethylwyosine (dYt), a derivative of rare tricyclic nucleoside wyosine with several oxidative radicals, has been studied by using pulse radiolysis. The transient spectra of the radicals dYt˙+ and dYt(-H)˙ and the p K a of the radical cation were measured. The rate constants of reactions of dYt with SO and CO radicals have been determined and related reaction mechanisms were discussed. [ABSTRACT FROM AUTHOR]

A series of chiral bis(NHC)−Pd(II) complexes bearing different coordinating counterions have been prepared and successfully applied in Et2Zn-mediated enantioselective umpolung allylation of aldehydes with cyclohexenyl acetate, affording the homoallylic alcohols in moderate to excellent yields (up to 96%), modest enantioselectivities (54%−66% ee), and good to excellent syn diastereoselectivities (up to 99:1 dr). [ABSTRACT FROM AUTHOR]

A set of N-dimension linear-coupled first-order differential equations were solved by a new method, which leads to a very simple iterative scheme. Based on the split-step Fourier technique, a simple and efficient algorithm was developed for analyzing pulse propagation in an N-core linear-coupled nonlinear coupler with the linear mismatch, loss, gain, higher order dispersion, and intermodal dispersion effect. It inherits the advantages of simplicity, flexibility, good accuracy, and relatively modest computing cost of the split-step Fourier method in single fiber. [ABSTRACT FROM PUBLISHER]

1 × 1 μm2 via hole structure ZnO-based resistive random access memory cells are fabricated and the resistive switching behavior is investigated. It can be found that with 5.7% hafnium-doped ZnO film, the memory cell shows remarkable 108 pulse endurance. An ON/OFF resistance ratio of at least two orders of magnitude is achieved and the resistive states can remain stable up to 104 s. In contrast, a Pt/ZnO/TiN control device presents an unstable resistive switching characteristic and endurance degradation. Compared with pure ZnO film, Hf-doped ZnO film has a relatively smoother surface and larger band gap. X-ray photoelectron spectroscopy analysis indicates that the Hf-doped element induces more non-lattice oxygen ions in the ZnO switching layer. We deduce that the conductive filament forms/ruptures in a fixed path along the Hf atoms. Based on I–V curve fitting and temperature-dependent current measurements, the Pt/Hf:ZnO/TiN device is demonstrated as a Schottky conduction mechanism, which shows reasonable agreement with the possible resistive switching mechanism in the hafnium-doped ZnO memristive device. [ABSTRACT FROM AUTHOR]

The magnetic properties of CoZr magnetic thin films with stripe domains are investigated. The nanocrystalline grain size of 21.2 nm of CoZr thin film was obtained by x-ray diffraction spectra. The rotatable stripe-domain structure of the samples can be clearly observed from the magnetic force microscopy images. From the results of the M–H loop, the typical loops with domain structure of the samples can also be seen. The saturation magnetic fields of the thin films increase as a function of stripe half period in static magnetic properties. In dynamic magnetic properties, we find two precession modes, which include one traditional uniform precession mode with the resonance peak position in the low-frequency band and the other as the non-uniform precession mode with the resonance peak position in the high-frequency band. The ferromagnetic resonance frequencies of the non-uniform procession mode, which are driven by the exchange coupling between adjacent domains, show a decrease in behavior from 5.11to 3.52 GHz in the zero-field dynamic permeability spectra with the stripe domain’s half period increasing, while the ferromagnetic resonance frequencies of the uniform procession mode nearly remain constant. Similar behavior of exchange coupling can be found by analyzing the field-dependent dynamic permeability spectra of CoZr films, which indicates that the main contribution of the thickness-dependent resonance frequency is the exchange coupling between neighboring stripe domains. [ABSTRACT FROM AUTHOR]

We investigate the thickness dependent magnetic properties of an exchange coupled bilayer consisting of Co/FeNi. Inside these bilayers, both acoustic and optical modes of ferromagnetic resonance exist, which are produced by the in-phase and out-of-phase precession of the spins in the different layers. The optical mode ferromagnetic resonance, with a much higher resonance frequency, can be tuned significantly by changing the thickness of the FeNi layer. We show that the thickness dependent optical ferromagnetic resonance frequency is due to the variations of the interlayer exchange coupling with the changes in thickness. [ABSTRACT FROM AUTHOR]

Extension of the GSMW Formula in Weaker Assumptions In this note, the generalized Sherman-Morrison-Woodbury (for short GSMW) formula (A + YGZ*) Aʘ A AʘY(Gʘ + Z* Aʘy) ʘZ* Aʘ is extended under some assumptions weaker than those used by Duan, 2013. [ABSTRACT FROM AUTHOR]

A mine intrinsically safe audio and video recorder is designed. The device is based on 5G SOC processor, and adopts the photosensitive sensor + white light/infrared laser fill light + intrinsically safe circuit scheme. Under the environment of low illumination, full black or confined space, it can collect, compress, store and display 4K high-definition video images, and transmit the collected audio and video data in real time. The recorder has the characteristics of high imaging quality, long shooting distance and low power consumption in low illumination environment; it supports TCP/IP, UDP, RTP, ONVIF, GB28181 and other protocols. In addition to serving as an underground information record, it can also assist the emergency headquarters in carrying out rescue operations in time. The test results show that the picture resolution of the recorder is 10 688×6 012, the video resolution is 2 560×1 440, the visual distance is 20 m, the data packet loss rate is about 0.068%, the delay is about 15.85 ms, and it can achieve continuous video recording for 9 hours or continuous video playback for 4 hours.

Objective To analyze the safety of perioperative prophylactic anticoagulant therapy in patients undergoing laparoscopic nephron-sparing surgery. Methods Clinical data of 84 cases underwent laparoscopic nephron-sparing surgery were retrospectively analyzed. The baseline data, intraoperative blood loss, intraoperative blood transfusion rate, postoperative rebleeding rate, postoperative hemoglobin reduction value, and postoperative length of hospital stay were recorded. These parameters were statistically compared between patients treated with perioperative prophylactic anticoagulant therapy （medicine group, n = 50） and without perioperative prophylactic anticoagulant therapy （non-medicine group, n = 34）. Results There was no significant difference in intraoperative blood loss （50.0 （30.0,100.0）mL vs.50.0 （45.0,100.0）mL）, intraoperative blood transfusion rate （0 vs.2.9%）, postoperative rebleeding rate （4.0% vs.2.9%）, postoperative hemoglobin reduction value （14.0（8.0,23.0） g/L vs.17.7（9.3,28.5） g/L）, and postoperative length of hospital stay （6.0（5.0,7.0）d vs.7.0（4.0,9.3）d）between the medicine and non-medicine groups （all P > 0.05）. Conclusion Perioperative prophylactic anticoagulation is safe and feasible for patients undergoing laparoscopic nephron-sparing surgery.

Patterns of movement through time are important components of animal behavior and key to understanding animal ecology. Due to methodological challenges, including tracing and analyzing movements and their changes, they are seldom studied to identify both seasonal patterns and their driving forces. Using seven GPS-collared red-crowned cranes (Grus japonensis, RCCs), we recorded their moving distances and concurrent climatic data to analyze the relative importance of these factors in RCC movements. Temperature was identified as the most important of these climatic variables in RCC movements. Based on temperature dependence and researcher expertise, we determined RCC temporal movement patterns as mating, brooding, wading, and growing with specific temporal periods partitioning. With the distance quantile of movement, we also identified the preferred temperature ranges in each temporal pattern. The four specific temporal partitionings of breeding movement and their preferred temperature ranges can effectively help wildlife managers devise conservation budgets and allocate resources. Our study provides a robust methodology in the partitioning of avian temporal movement patterns and further the understanding of animal behavior ecology, which is applicable to the study and conservation of other species, as well as for RCCs. [ABSTRACT FROM AUTHOR]

The aim of this study was to isolate protoplasts from different metal resistant endophytic fungi and to carry out interspecific fusion of protoplasts to enhance bioremediation of contaminated soils. Three stable fusants (F1, F2, and F3) with resistance to Cd and Zn were constructed by interspecific fusion between inactivated protoplasts from Cd-resistant endophytic Mucor sp. CBRF59 and Zn-resistant endophytic Fusarium sp. CBRF14. The fusants increased concentrations of water soluble Cd, Pb, and Zn in soils, promoted rape growth, increased metal concentrations in the rape, elevated the extractable metal amount, and increased metal translocation from roots to shoots in soils containing single metals or multi-metals. Especially, the fusants showed much higher extraction efficacy than the parents in soils contaminated by multi-metals. The results indicated that protoplast fusion should be a feasible and efficient fungal method, which could be utilized to construct stable fusants by combining the genetic traits of parents for bioremediation of contaminated soils by multi-metals. [ABSTRACT FROM AUTHOR]

In this article the authors discuss the challenges of reusing mining and mineral-processing wastes. They argue that mining and mineral-processing wastes are one of the world's largest waste concerns, adding that their reuse needs to be included in sustainable development plans. They note that the environmental impact of these wastes processes varies and thorough assessment is needed to determination the most appropriate and economically feasible ways for their reuse. A discussion on how a proper evaluation of the chemical composition and geotechnical properties of the source rock can be used to determine appropriate and feasible uses of mine and mineral wastes is presented.