Sexual spores in edible mushroom: bioactive components, discharge mechanisms and effects on fruiting bodies quality

Edible mushroom sexual spores have been gaining more interest due to their bioactive components and functions.Spore discharge(SD)is an important factor affecting the quality of edible mushrooms.In this review,the bioactive nutrients of sexual spores of edible mushrooms were summarized,the SD mechanism was described,and the relationship between postharvest SD and the quality of edible mushrooms was analyzed.Spores contain various bioactive nutrients that are benefi cial to the human body.Mature mushrooms can actively discharge spores in a process affected by light,relative humidity,and temperature.During storage,the physiological metabolism of spore-bearing gill tissue is vigorous,promoting the release of postharvest spores and changing the nutritional value of fruiting bodies.The flavor of the fruiting bodies also varied signifi cantly during SD.Edible mushroom sexual spores have the potential to become new raw materials for functional food and medical resources.Research on the effect of the mechanism of SD on the quality of edible mushrooms and the development of SD regulation technology may be a new trend in the quality control of edible mushrooms,which will promote the development of the edible mushroom industry.

Effect of antenna helicity on discharge characteristics of helicon plasma under a divergent magnetic field

The characteristics of the blue core phenomenon observed in a divergent magnetic field helicon plasma are investigated using two different helical antennas, namely right-handed and lefthanded helical antennas. The mode transition, discharge image, spatial profiles of plasma density and electron temperature are diagnosed using a Langmuir probe, a Nikon D90 camera,an intensified charge-coupled device camera and an optical emission spectrometer, respectively.The results demonstrated that the blue core phenomenon appeared in the upstream region of the discharge tube at a fixed magnetic field under both helical antennas. However, it is more likely to appear in a right-handed helical antenna, in which the plasma density and ionization rate of the helicon plasma are higher. The spatial profiles of the plasma density and electron temperature are also different in both axial and radial directions for these two kinds of helical antenna. The wavelength calculated based on the dispersion relation of the bounded whistler wave is consistent with the order of magnitude of plasma length. It is proved that the helicon plasma is part of the wave mode discharge mechanism.

A quantum-chemical study on the discharge reaction mechanism of lithium-sulfur batteries

Lithium-sulfur batteries have attracted a great interest in electrochemical energy conversion and storage, but their discharge mechanism remains not well understood up to now. Here, we report density functional theory （DFr） calculation study of the discharge mechanism for lithium-sulfur batteries which are based on the structure of $8 and Li2Sx （l_〈x〈_8） clusters. The results show that for LizSz （1 〈x_8） clusters, the most stable geometry is chainlike when x = 1 and 6, while the minimal-energy structure is found to be cyclic when x = 2-5, 7, 8. The stability of LizSx （l_〈x_〈 8） clusters increases with the decreasing x value, indicating a favorable thermodynamic tendency of transition from $8 to Li2S. A three-step reaction route has been proposed during the discharge process, that is, $8---~Li2S4 at about 2.30 V, Li2S4---~Li2S2 at around 2.22 V, and Li2S2 ~ Li2S at 2.18 V. Furthermore, the effect of the electrolyte on the potential platform has been also investigated. The discharge potential is found to increase with the decrease of dielectric constant of the electrolyte. The computational results could provide insights into further understanding the discharge mechanism of lithium-sulfur batteries.

Analysis of Dissociation Mechanism of CO_2 in a Micro-Hollow Cathode Discharge

Considering the feature of distributions of parameters within the micro-hollow cathode discharge, we use a simple method to separate the sheath region characterized by drastic changes of plasma parameters and the bulk plasma region characterized by smooth changes of plasma parameters. A zero-dimensional chemical kinetic model is used to analyze the dissociation mechanism of CO2 in the bulk plasma region of a micro-hollow cathode discharge and is validated by comparisons with previous modeling and experimental results. The analysis of the chemical kinetic processes has shown that the electron impact dissociation and heavy species impact dissociation are dominant in different stages of the rnicro-hollow cathode discharge process for a given applied voltage. The analysis of energy consumption distributions under different applied voltages reveals that the main reason of the conversion improvement with the increase of the applied voltage is that more input energy is distributed to the heavy species impact dissociation.

Regulating the nucleation of Li_(2)CO_(3) and C by anchoring Li-containing carbonaceous species towards high performance Li-CO_(2) batteries

Li-CO_(2) batteries provide an attractive and potential strategy for CO_(2) utilization as well as energy conversion and storage with high specific energy densities.However,the poor reversibility caused by the decomposition obstacles of Li_(2)CO_(3) and C products is still a challenge for Li-CO_(2) batteries,which seriously influences its electrochemical performances.Herein,a free-standing MnOOH arrays cathode has been prepared and employed in Li-CO_(2) battery,which realizes a great improvement of electrochemical performances by adjusting the discharge products distribution.Experiments coupled with theoretical calculations verifies that the formation of Li-containing carbonaceous species(LiCO_(2),LiCO and Li_(2) CO_(3))bonded with MnOOH through Li ion regulates the nucleation behavior of Li_(2)CO_(3) and C,making them grown on MnOOH uniformly.The fine Li_(2) CO_(3) grains(with a size about 5 nm)embedded into carbon matrix greatly enlarges the contact interface between them,facilitating the transmission of electrons through the discharge products and finally improves CO_(2) evolution activity.This ingenious design strategy of regulating discharge products distribution to improve electrochemical performances provides a promising way to develop advanced Li-CO_(2) batteries.

OH and O radicals production in atmospheric pressure air/Ar/H_2O gliding arc discharge plasma jet

Atmospheric pressure air/Ar/H_2O gliding arc discharge plasma is produced by a pulsed dc power supply. An optical emission spectroscopic（OES） diagnostic technique is used for the characterization of plasmas and for identifications of OH and O radicals along with other species in the plasmas. The OES diagnostic technique reveals the excitation Tx？≈？5550–9000 K, rotational Tr？≈？1350–2700 K and gas Tg？≈？850–1600 K temperatures, and electron density n？（1.1-1.9） ′101 4 cm^（-3） e under different experimental conditions. The production and destruction of OH and O radicals are investigated as functions of applied voltage and air flow rate. Relative intensities of OH and O radicals indicate that their production rates are increased with increasing Ar content in the gas mixture and applied voltage. nereveals that the higher densities of OH and O radicals are produced in the discharge due to more effective electron impact dissociation of H_2O and O_2 molecules caused by higher kinetic energies as gained by electrons from the enhanced electric field as well as by enhanced n e.The productions of OH and O are decreasing with increasing air flow rate due to removal of Joule heat from the discharge region but enhanced air flow rate significantly modifies discharge maintenance properties. Besides, Tgsignificantly reduces with the enhanced air flow rate. This investigation reveals that Ar plays a significant role in the production of OH and O radicals.

Systematic evaluation of advance in application and discharge mechanism of solution electrode glow discharge

As a kind of microplasma sustained in air,solution electrode glow discharge(SEGD)ignited between the liquid electrode and metal electrode is attractive to the fields of optical emission spectrometry and mass spectrometry due to its unique advantages,such as low power consumption and low carrier gas consumption.Moreover,the complex and efficient reactions in the liquid phase and plasma phase of SEGD make it considerable research potential in the fields of biology and medicine,material synthesis,electrochemistry.Considering the close relationship between the various fields on SEGD,here we are devoted to provide an overview of the development of SEGD in various fields.More importantly,a systematic discussion on the discharge mechanism is conducted based on the research process in various fields for getting deeper insight into the SEGD.

NUMERICAL SIMULATION OF FLOW THROUGH ORIFICE ENERGY-DISSIPATORS IN XIAOLANGDI FLOOD-DISCHAR-GE TUNNEL

Cavitation of orifices is one of the main problems of the Xiaolangdi flood discharge tunnels. Along with the decompression experiment, the flow field was calculated by using an axis-symmetrical κ-Ε turbulence model. The calculated pressure distribution was compared with the measured data and in agreement with each other. The calculated results show that few of the cavitation bubbles generating at the orifice edge can reach the wall under the calculation condition, the force applied on the orifice surface and the flow pattern before the orifice may be improved obviously by adding the vortex elimination ring at the upper side of the orifice.

DISCHARGE DISTRIBUTION IN STRAIGHT COMPOUND CHANNELS

The existing methods of computing the flow distribution in compound channels with flood plains have been summarized. A new method called the momentum-exchange method was presented and verified with experimental and field data. The results show that the new method is more effective than previous ones.

THREE-DIMENSIONAL NUMERICAL SIMULATION OF MUL-TIPLE JETS IN SHALLOW FLOWING RECEIVING WATERS

Simulation of the mixing mechanism of submerged multiport diffusers used to discharge heated water from thermal-electric power plants and households into shallow receiving waters was described. The three-dimensional turbulence model and hybrid finite analytic method were used to predict the behavior of near field for multiport buoyant jets in rivers. The predicted temperature dilution and velocity prove good by comparison with available laboratory measurements. An empirical formula for temperature dilution and velocity in near field for this kind of flow was given. The effect of parameters on the dilution behavior of multiple jets were also discussed.

Local neuronal circuits that may shape the discharge patterns of inferior collicular neurons

The discharge patterns of neurons in auditory centers encode information about sounds.However,few studies have focused on the synaptic mechanisms underlying the shaping of discharge patterns using intracellular recording techniques.Here,we investigated the discharge patterns of inferior collicular（IC）neurons using intracellular recordings to further elucidate the mechanisms underlying the shaping of discharge patterns.Under in vivo intracellular recording conditions,recordings were obtained from 66 IC neurons in 18 healthy adult mice（Mus musculus,Km）under free field-stimulation.Fiftyeight of these neurons fired bursts of action potentials（APs）to auditory stimuli and the remaining eight just generated local responses such as excitatory（n=4）or inhibitory（n=4）postsynaptic potentials.Based on the APs and subthreshold responses,the discharge patterns were classified into seven types：phasic（24/58,41.4%）,phasic burst（8/58,13.8%）,pauser（4/58,6.9%）,phasic-pauser（1/58,1.7%）,chopper（2/58,3.4%）,primary-like tonic（14/58,24.1%）and sound-induced inhibitory（5/58,8.6%）.We concluded that（1）IC neurons exhibit at least seven distinct discharge patterns;（2）inhibition participates in shaping the discharge pattern of most IC neurons and plays a role in sculpting the pattern,except for the primary-like tonic pattern which was not shapedby inhibition;and（3）local neural circuits are the likely structural basis that shapes the discharge patterns of IC neurons and can be formed either in the IC or in lower-level auditory structures.

STUDY ON THE CHARACTERISTICS OF LONG TERM DISCHARGE OF A CATCHMENT

The characteristics of the catchment discharge vary with land use. The characteristics of the long-term discharge of a terraced paddy field catchment were studied. Two kind of tank models for land use were proposed and used to simulate the discharge of the catchment: one is a forest type model used as the upper part of the catchment; the other is a paddy field type model used as the lower part of the catchment. The results of the model simulation were analyzed and compared with that of a forest catchment.

Electrical Discharge Machining of Al2024-65 vol%SiC Composites

In the present work, the wire electrical discharge machining（WEDM） process of the 65 vol% SiCp/2024 Al composite prepared by pressure infiltration methods has been investigated. The microstructure of the machined composite was characterized by scanning electron microscope, the average surface roughness（Ra）, X-ray diffraction, X-ray photoelectron spectroscopy and transmission electron microscopy（TEM） techniques. Three zones from the surface to the interior（melting zone, heat affected zone and un-affected zone） were found in the machined composites, while the face of SiC particles on the surface toward the outside was ‘‘cut＇＇ to be flat. Increase in Al and Si but decrease in C and O were observed in the core areas of the removed particles. Si phase, which was generated due to the decomposition of SiC, was detected after the WEDM process. The irregular and spherical particles were further observed by TEM. Based on the microstructure observation, it is suggested that the machining mechanism of 65 vol% SiCp/2024 Al composite was the combination of the melting of Al matrix and the decomposition of SiC particles.

RELATION OF DEBRIS FLOW DEPTH AND CURVATURE RADIUS OF DISCHARGE GUIDE DITCH

Theoretical approach to the relation of different type of debris flow and curvature radius of discharge guide ditch and expression for estimating water surface freeboard, with the consideration of debris flow characteristics with rational structure, were described. The relevant formulae were simplified and verified by measurement data. The results show good coincidence of the estimated values with measured data.

STUDY ON JETS IMPACT IN AIR FOR ENERGY DISSIPATION

This paper is concerned with the applications of water jet impact in air to energy dissipation. The scattered jet flow impinges into the downstream water plunge pool, which greatly improves the inflow condition of the submerged jet in the pool and make it diffuse very quickly. The model experiments were conducted, which showed that a large jet flow could be scattered by a small one through impacting. The minimum discharge ratio for flow dispersion was studied. The unequal jet impact in air for energy dissipation was brought forward firstly in this paper as a new type of energy dissipator.