The ion levels in the epidermal bulliform cells of epidermis, mesophyll cells and cells of the vascular bundle sheath of four ecotypes of reed (Phragmites australis (Cav.) Trin. ex Steud.) were determined by means of ...The ion levels in the epidermal bulliform cells of epidermis, mesophyll cells and cells of the vascular bundle sheath of four ecotypes of reed (Phragmites australis (Cav.) Trin. ex Steud.) were determined by means of X_ray microanalysis. The results indicated that higher K +, Na +, Ca 2+ , Mg 2+ and Cl - were distributed in the vascular bundle sheath cells than in mesophyll cells and epidermal bulliform cells of the swamp ecotype. Higher Ca 2+ was found in the bulliform cells than in mesophyll cells and vascular bundle sheath cells, higher Mg 2+ in the mesophyll cells and higher K +, Na + and Cl - in the vascular bundle sheath cells of the dune ecotype. Higher Na + and Mg 2+ was determined in the mesophyll cells than in the bulliform cells and vascular bundle sheath cells, and higher K +, Ca 2+ and Cl - in the vascular bundle sheath cells of the light salt meadow ecotype. In the heavy salt meadow ecotype, higher Na + and Mg 2+ were accumulated in the bulliform cells than in mesophyll cells and vascular bundle sheath cells, but higher K +, Ca 2+ and Cl - in the mesophyll cells. Furthermore, the distributional conditions of the above five ions in leaf cells of the four ecotypes and their significance in the physiological adaptation of reed to habitat were discussed in detail.展开更多
The effects of neutral salt and alkali on the ion distribution were investigated in two alfalfa (Medicago sativa L.) cultivars, including Zhongmu 1, a high salt-tolerant cultivar, and Algonquin, a low salt-tolerant ...The effects of neutral salt and alkali on the ion distribution were investigated in two alfalfa (Medicago sativa L.) cultivars, including Zhongmu 1, a high salt-tolerant cultivar, and Algonquin, a low salt-tolerant cultivar. The alkali stress expressed more serious growth inhibition than the neutral salt stress at the same Na+ concentration. Compared with Algonquin, Zhongmu 1 did not exhibit a higher alkali tolerance under the Na2CO3-NaHCO3 treatment with the low Na+ concentration (50 mmol L-l). The alkali increased the accumulation of Na+, Ca2+, and Mg2+ in the root and changed the Ca2+ and Mg2+ balance in the entire alfalfa plant. The salt and alkali stresses decreased the K+ and Fe3+ contents of the roots and leaves, the root Mn2+ content, and the shoot Zn2+ content, but they increased the Fe3+ accumulation of the shoots, the shoot and leaf Cu2+ contents, and the leaf Zn2+ content in both alfalfa cultivars. Based on the results obtained under the conditions of this experiment, we found that the salt and alkali stresses reduced the plant growth in both alfalfa cultivars, while the alkali caused a stronger stress than the neutral salt in alfalfa. Thus, we conclude that under hydroponic conditions, the deleterious effects of the alkali on plants are due to the distribution change of some trophic ion balance in the roots, shoots, and leaves of the plants by causing of Na+, CO3^2-, and/or HCO3- stresses.展开更多
A formula was proposed to calculate the distribution of metal ions quantitatively in chemical reaction system forming hydroxide where precipitation and complex are formed together. The effects of some factors on forma...A formula was proposed to calculate the distribution of metal ions quantitatively in chemical reaction system forming hydroxide where precipitation and complex are formed together. The effects of some factors on formation of precipitation and complex were investigated, and the corresponding precipitation rates of zinc, iron (III), aluminum, copper and magnesium were calculated. As a result, it shows that the proposed formula is reliable. By the proposed formula, the existence state of metal ions in hydroxides reaction system with any metal ions can be well described and the effects of some factors on the distribution of metal ions were determined.展开更多
In order to investigate the effect of an arbitrary dust size distribution for vortex-like ion distributiondusty plasma,we use a reasonable polynomial-expressed function to represent an arbitrary dust size distribution...In order to investigate the effect of an arbitrary dust size distribution for vortex-like ion distributiondusty plasma,we use a reasonable polynomial-expressed function to represent an arbitrary dust size distribution.Thenumerical results of linear dispersion relation,nonlinear solitary wave amplitude,width and velocity for polynomialexpressed dust size distribution dusty plasma with vortex-like ion distribution have been studied.展开更多
An Asparagus officinalis L. cultivar NJ978 was used to study the growing rate, salt ion content and mineral ion uptake and distribution in plants under salt stress. The results showed that salt stress significantly in...An Asparagus officinalis L. cultivar NJ978 was used to study the growing rate, salt ion content and mineral ion uptake and distribution in plants under salt stress. The results showed that salt stress significantly inhibited seedling growth and there was a negative relationship between seedling growth and salt concentration. The seedlings growth showed no significant decrease under low salt stress (NaCl≤50 mmol/L), while high concentrations of NaCl led to detrimental effects on the growth of A. officinalis L.. With the increase of NaCl concentration, the Na + content increased gradually in A. officinalis L. roots, stems and leaves while the K^+ and Ca^2+ contents had slow decreases. Under low salt stress, the seedlings of A. officinalis L. could prevent Na + from transporting to aerial part by withholding Na + in root, which could keep the balance of ions in aerial part, but under high salt stress (NaCl 〉 100 mmol/L), the aerial part of seedlings accumulated superabundance of Na +, which limited the uptake of K^+ and Ca^2+ , so seedlings were damaged heavily, which manifested as the gradual decrease of K^+/Na + and Ca^2+ /Na + in the roots and aerial part of the seedlings. The selective absorption of K^+, Ca^2+ and Na + (AS K,Na and AS Ca,Na ) was significantly increased with increased salinity, while the selective transportation (TS K,Na and TS Ca,Na ) increased at first and then decreased with the increased salinity. Therefore, the strong ability of salt exclusion and the regionalized distribution of ions in roots, stems and leaves could be one of the salt tolerance mechanisms of A. officinalis L.展开更多
Aqueous zinc metal batteries (AZMBs) are hindered by uncontrolled dendrites and side reactions during commercialization,despite their advantages of safety and high capacity density.Herein,we propose the electrical fee...Aqueous zinc metal batteries (AZMBs) are hindered by uncontrolled dendrites and side reactions during commercialization,despite their advantages of safety and high capacity density.Herein,we propose the electrical feedback strategy to restrain the Zn dendrites resulting from the"tip effect"and optimize interfacial Zn^(2+)distribution to accelerate electrodeposition kinetics by using the lithium niobate (LNO) layer.Specifically,at the bumps of the zinc anode,the ferroelectric LNO is polarized by the locally strong electric field,which in turn counteracts the"tip effect".In this way,the dynamic polarization of LNO can repair the uneven tip electric field to achieve uniform and flat zinc deposition.In addition,owing to the interaction between Nb and Zn^(2+),a higher concentration of Zn^(2+)near the zincophilic LNO@Zn surface is obtained for the rapid electrochemical reaction kinetics of plating.Considering the aforementioned advantages,the LNO@Zn anode harvests stable cycling over 1200 h at 10 mA cm^(-2)with a superior cumulative capacity of 5800 mAh cm^(-2).Assembled with the a-MnO_(2) cathode,the full cell using LNO@Zn anode exhibits the slower capacity decay (0.054%per cycle) during 1000 cycles.This strategy provides a perspective for stabilizing zinc metal anodes through dynamic electrical response and interfacial ion redistribution effect.展开更多
Transpiration rate and ion distribution of pagoda tree, walnut, velvet ash and poplar seedlings treated by NaCl solution of 0, 50, 100, 200 mmol·L-1 were studied. The results showed that there were significant di...Transpiration rate and ion distribution of pagoda tree, walnut, velvet ash and poplar seedlings treated by NaCl solution of 0, 50, 100, 200 mmol·L-1 were studied. The results showed that there were significant differences in the response to NaCl among the four tree species. Na+ exclusion capacity of pagoda tree was the largest among the four species. The Na+ exclusion capacity of velvet ash was less than that of pagoda tree. Salt excretion capacity of velvet ash was limited. Its salt-tolerance was bigge...展开更多
The ion density distribution in the reaction chamber was diagnosed by a Langmuir probe. The rules of the ion density distribution were obtained under the pressures of 9 Pa, 13 Pa, 27 Pa and 53 Pa in the reaction chamb...The ion density distribution in the reaction chamber was diagnosed by a Langmuir probe. The rules of the ion density distribution were obtained under the pressures of 9 Pa, 13 Pa, 27 Pa and 53 Pa in the reaction chamber, different radio-frequency powers and different positions. The result indicates that the ion density decreases as the pressure increases, and increases as the power decreases. The ion density of axial position z =0 achieves 5.8×1010 on the center of coil under the power of 200 w and pressure of 9 Pa in the reaction chamber.展开更多
The pitch angle distributions of ions and electrons can be affected by various processes;thus,they can serve as an important indicator of the physical mechanisms driving the dynamics of space plasmas.From observations...The pitch angle distributions of ions and electrons can be affected by various processes;thus,they can serve as an important indicator of the physical mechanisms driving the dynamics of space plasmas.From observations from the Mars Ion and Neutral Particle Analyzer onboard the Tianwen-1 orbiter,we calculated the pitch angle distributions of protons in the Martian induced magnetosphere by using information from the magnetohydrodynamically simulated magnetic field,and we statistically analyzed the spatial occurrence pattern of different types of pitch angle distributions.Even though no symmetrical features were seen in the dataset,we found the dominance of the field-aligned distribution type over the energy range from 188 to 6232 eV.Maps of the occurrence rate showed the preferential presence of a trapped-like distribution at the lower altitudes of the surveyed nightside region.Although our results are more or less restricted by the adopted magnetic field,they indicate the complexity of the near-Mars proton pitch angle distributions and infer the possibility of wave–particle interactions in the Martian induced magnetosphere.展开更多
Propellant ionization in the Hall thruster discharge channel is a significant process and has strong influence on the thruster's efficiency. In this work, the functional relation has been established between the ioni...Propellant ionization in the Hall thruster discharge channel is a significant process and has strong influence on the thruster's efficiency. In this work, the functional relation has been established between the ionization density distribution and the function of the ion energy distribution through the basic equations governing the ion flow in the Hall thruster channel and the method achieved for reconstructing the ionization density distribution inside the channel by ordinary plasma diagnosis of the potential distribution and ion energy spectrum of the plasma jet. The ionization density distributions of single and double charged ions in an ATON-thruster channel have been reconstructed according to the experimental data of the potential distribution along the axis of the channel and the ion energy spectrum of the plasma jet. The agreement between the calculation and experimental results of the percentage of double charged ions proves the validity of our method achieved in this work.展开更多
A retarding field energy analyzer(RFEA) is used to measure the time-averaged ion energy distributions(IEDs) on the substrate in both continuous wave(CW) and synchronous pulse modulated radio-frequency(RF) indu...A retarding field energy analyzer(RFEA) is used to measure the time-averaged ion energy distributions(IEDs) on the substrate in both continuous wave(CW) and synchronous pulse modulated radio-frequency(RF) inductively coupled Ar plasmas(ICPs).The effects of the phase shift θ between the RF bias voltage and the RF source on the IED is investigated under various discharge conditions.It is found that as θ increases from 0 to π,the IED moves towards the low-energy side,and its energy width becomes narrower.In order to figure out the physical mechanism,the voltage waveforms on the substrate are also measured.The results show that as θ increases from 0 to π,the amplitude of the voltage waveform decreases and,meanwhile,the average sheath potential decreases as well.Specifically,the potential drop in the sheath on the substrate exhibits a maximum value at the same phase(i.e.,θ = 0) and a minimum value at the opposite phase(i.e.,θ = π).Therefore,when ions traverse across the sheath region above the substrate,they obtain less energies at lower sheath potential drop,leading to lower ion energy.Besides,as θ increases from π to 2π,the IEDs and their energy widths change reversely.展开更多
Resonance lines are extensively used to diagnose electronic temperature Te and ions distribution. However, the analysis of the x-ray spectroscopy emitted from plasmas produced by a ns laser Jsually needs the help of a...Resonance lines are extensively used to diagnose electronic temperature Te and ions distribution. However, the analysis of the x-ray spectroscopy emitted from plasmas produced by a ns laser Jsually needs the help of a code or some assumptions. In this paper, a diagnostic idea of using line-pairs emitted from a doubly-excited state is proposed. By using the method presented in this paper, Te and the fractional population ratio of bare nuclei and H-like ions are directly obtained from the emission intensity ratios.展开更多
This study delves into ion behavior at the substrate position within RF magnetron discharges utilizing an indium tin oxide(ITO)target.The positive ion energies exhibit an upward trajectory with increasing RF power,att...This study delves into ion behavior at the substrate position within RF magnetron discharges utilizing an indium tin oxide(ITO)target.The positive ion energies exhibit an upward trajectory with increasing RF power,attributed to heightened plasma potential and initial emergent energy.Simultaneously,the positive ion flux escalates owing to amplified sputtering rates and electron density.Conversely,negative ions exhibit broad ion energy distribution functions(IEDFs)characterized by multiple peaks.These patterns are clarified by a combination of radiofrequency oscillation of cathode voltage and plasma potential,alongside ion transport time.This elucidation finds validation in a one-dimensional model encompassing the initial ion energy.At higher RF power,negative ions surpassing 100 e V escalate in both flux and energy,posing a potential risk of sputtering damages to ITO layers.展开更多
In the context of unified hydrodynamics, we discuss the pseudorapidity distributions of the charged particles produced in Au-Au and Cu-Cu collisions at the low RHIC energies of √SNN = 19.6 and 22.4 GeV, respectively....In the context of unified hydrodynamics, we discuss the pseudorapidity distributions of the charged particles produced in Au-Au and Cu-Cu collisions at the low RHIC energies of √SNN = 19.6 and 22.4 GeV, respectively. It is found that the unified hydrodynamics alone can give a good description to the experimental measurements. This is different from the collisions at the maximum RHIC energy of √SNN = 200 GeV or at LHC energy of √SNN= 2.76 TeV, in which the leading particles must be taken into account so that we can properly explain the experimental observations.展开更多
To investigate the effect of the rib structure on the discharge characteristics of the plasma display panel, the potential distribution, particles density distribution and ions incident angle distribution were examine...To investigate the effect of the rib structure on the discharge characteristics of the plasma display panel, the potential distribution, particles density distribution and ions incident angle distribution were examined by simulation of a two-dimensional particle-in-cell/Monte Carlo collision, with two kinds of rib structure: the stripe rib structure and the Waffle rib structure. The results showed that the distribution of electric potential at the corner of the discharge cell was almost the same for these two rib structures while in the centre there was a difference between these two rib structures. The striation phenomenon could be observed in both cases. The distribution of density also indicated that the striation phenomenon was accompanied by the firing of discharge, and the Waffle rib structure might reduce the density humps. In the cell with a stripe rib structure, the profiles of the surface charge density along the sustained dielectric layer presented a better fluctuating distribution than that in the cell with a Waffle rib structure. The spatial potential and particle density in the discharge bulk showed that the Waffle ribs could weaken the striation phenomenon, which could be explained by the decrease in the particle numbers in the discharge cell. The simulation results of the ion incident angle showed that most ions impacted the sustained dielectric layer in the normal stripe rib cell with an incident angle in the range of 6° to 19° while with the Waffle rib structure the incident angle of most ions was in the range of 4° to 19°. The Waffle rib structure did not affect the angle distribution of incident ions significantly.展开更多
Several of new chelating resins containing sulfoxide and heterocyclic functional groups (3-aminopyridine and 2-mercaptobenzothiazole) based on macroporous chloromethylated polystyrene were synthesized and characteri...Several of new chelating resins containing sulfoxide and heterocyclic functional groups (3-aminopyridine and 2-mercaptobenzothiazole) based on macroporous chloromethylated polystyrene were synthesized and characterized by elemental analysis and infrared spectra. Their adsorption capacities towards Zn^2+, Cu^2+, Pb^2+, Hg^2+ and Ag^+ at pH 3.0 and 6.0 were investigated in detail. It was found that the adsorption capacities of the resins containing bis[(3-pyridylaminoethyl)sulfoxide or (2-benzothiazolylthioethyl)sulfoxide for the above ions were higher than that on ones containing single above-mentioned groups.展开更多
Lithium ion battery has typical character of distributed parameter system, and can be described precisely by partial differential equations and multi-physics theory because lithium ion battery is a complicated electro...Lithium ion battery has typical character of distributed parameter system, and can be described precisely by partial differential equations and multi-physics theory because lithium ion battery is a complicated electrochemical energy storage system. A novel failure prediction modeling method of lithium ion battery based on distributed parameter estimation and single particle model is proposed in this work. Lithium ion concentration in the anode of lithium ion battery is an unmeasurable distributed variable. Failure prediction system can estimate lithium ion concentration online, track the failure residual which is the difference between the estimated value and the ideal value. The precaution signal will be triggered when the failure residual is beyond the predefined failure precaution threshold, and the failure countdown prediction module will be activated. The remaining time of the severe failure threshold can be estimated by the failure countdown prediction module according to the changing rate of the failure residual. A simulation example verifies that lithium ion concentration in the anode of lithium ion battery can be estimated exactly and effectively by the failure prediction model. The precaution signal can be triggered reliably, and the remaining time of the severe failure can be forecasted accurately by the failure countdown prediction module.展开更多
Non-intrusive characterization of the singly ionized xenon velocity in Hall thruster plume using laser induced fluorescence(LIF)is critical for constructing a complete picture of plume plasma,deeply understanding the ...Non-intrusive characterization of the singly ionized xenon velocity in Hall thruster plume using laser induced fluorescence(LIF)is critical for constructing a complete picture of plume plasma,deeply understanding the ion dynamics in the plume,and providing validation data for numerical simulation.This work presents LIF measurements of singly ionized xenon axial velocity on a grid ranging from 100 to 300 mm in axial direction and from 0 to 50 mm in radial direction for a600 W Hall thruster operating at the nominal condition of discharge voltage 300 V and discharge current 2 A,the influence of discharge voltage is investigated as well.The ion velocity distribution function(IVDF)results in the far-field plume demonstrate a profile of bimodal IVDFs,especially prominent at radial distances greater than channel inner radius of 22 mm at axial position of 100 mm,which is quite different from that of the near-field plume where bimodal IVDFs occur in the central core region for the same power Hall thruster when compared to previous LIF measurements of BHT-600 by Hargus(2010 J.Propulsion Power 26135).Beyond 100 mm,only single-peak IVDFs are measured.The two-dimensional ion velocity vector field indicates the bimodal axial IVDF is merely a geometry effect for the annular discharge channel in the far-field plume.Results about the IVDF,the most probable velocity and the accelerating potential profile along the centerline all indicate that ions are still accelerating at axial distances greater than 100 mm,and the maximum most probable velocity measured at300 mm downstream of the exit plane is about 19 km s-1.In addition,the most probable velocity of ions along radial direction changes a little except the lower velocity ion populations in the bimodal IVDF cases.The ion temperature at axial distances of 10 and 300 mm oscillates along the radial direction,while the ion temperature first increases,and then decreases for the 200 mm case.Finally,the axial position for the ion peak axial velocity on the thruster centerline is shifted upstream for higher discharge voltages,and the velocity curve is becoming steeper with the discharge voltage before reaching the maximum.This observation can be used as a criterion to optimize the thruster performance.展开更多
Recently,the quantitative rescattering model(QRS)for nonsequential double ionization(NSDI)is modified by taking into account the potential change(PC)due to the presence of electric field at the time of recollision.Usi...Recently,the quantitative rescattering model(QRS)for nonsequential double ionization(NSDI)is modified by taking into account the potential change(PC)due to the presence of electric field at the time of recollision.Using the improved QRS model,we simulate the longitudinal momentum distributions of doubly charged ions He2+by projecting the correlated two-electron momentum distributions for NSDI of He onto the main diagonal.The obtained results are compared directly with the experimental data at different intensities.It is found that when the PC is considered,the width of momentum distributions reduces and the agreement between theory and experiment is improved.展开更多
A hydroponic experiment with six treatments, i.e., 0% seawater (control), 10% seawater, 25% seawater, 0% seawater + N (7.5 mmol L-1 NaNO3), 10% seawater + N (7.5 mmol L-1 NaO3), and 25% seawater + N (7.5 mmo...A hydroponic experiment with six treatments, i.e., 0% seawater (control), 10% seawater, 25% seawater, 0% seawater + N (7.5 mmol L-1 NaNO3), 10% seawater + N (7.5 mmol L-1 NaO3), and 25% seawater + N (7.5 mmol L-1 NaNO3), was carried out to study the effect of nitrogen addition on the growth and physiological and biochemical characteristics of Jerusalem artichoke (Helianthus tuberosus) seedlings under seawater stress. The 10% seawater stress treatment had the least effect on plant growth while at 25% seawater growth was significantly inhibited. The malondialdehyde content and electrolyte leakage in leaves under 10% seawater were similar to those of the control, but significantly higher under the 25% seawater stress. The activities of superoxide dismutase, peroxidase and catalase in the leaves increased concomitantly with increasing seawater concentration and time. Proline and soluble-sugars in the leaves and Na^+, K^+, and Cl- contents in shoots and roots increased significantly with the concentration of seawater increasing. Nitrogen addition resulted in increasing fresh and dry weights of shoots and roots compared with seawater treatment without N. Nitrogen supplementation also significantly enhanced the activities of antioxidant enzymes in leaves. Addition of N to seawater enhanced the contents of proline and soluble-sugars in the leaves and K^+ and total-N in the aerial parts and roots of H. tuberosus, but it resulted in declined concentrations of Na^+ and Cl- in the aerial parts and roots. Nitrogen addition ameliorated the toxicity of seawater by improving the antioxidative enzymes, accumulating of proiine and soluble-sugars, and altering the distribution of inorganic ions in H. tuberosus.展开更多
文摘The ion levels in the epidermal bulliform cells of epidermis, mesophyll cells and cells of the vascular bundle sheath of four ecotypes of reed (Phragmites australis (Cav.) Trin. ex Steud.) were determined by means of X_ray microanalysis. The results indicated that higher K +, Na +, Ca 2+ , Mg 2+ and Cl - were distributed in the vascular bundle sheath cells than in mesophyll cells and epidermal bulliform cells of the swamp ecotype. Higher Ca 2+ was found in the bulliform cells than in mesophyll cells and vascular bundle sheath cells, higher Mg 2+ in the mesophyll cells and higher K +, Na + and Cl - in the vascular bundle sheath cells of the dune ecotype. Higher Na + and Mg 2+ was determined in the mesophyll cells than in the bulliform cells and vascular bundle sheath cells, and higher K +, Ca 2+ and Cl - in the vascular bundle sheath cells of the light salt meadow ecotype. In the heavy salt meadow ecotype, higher Na + and Mg 2+ were accumulated in the bulliform cells than in mesophyll cells and vascular bundle sheath cells, but higher K +, Ca 2+ and Cl - in the mesophyll cells. Furthermore, the distributional conditions of the above five ions in leaf cells of the four ecotypes and their significance in the physiological adaptation of reed to habitat were discussed in detail.
基金supported financially by the Open Project of the National Key Laboratory for Grassland Agro-ecosytems hosted at Lanzhou University,Chinathe construction project of Key Discipline of Jiangsu Province for grass science,China
文摘The effects of neutral salt and alkali on the ion distribution were investigated in two alfalfa (Medicago sativa L.) cultivars, including Zhongmu 1, a high salt-tolerant cultivar, and Algonquin, a low salt-tolerant cultivar. The alkali stress expressed more serious growth inhibition than the neutral salt stress at the same Na+ concentration. Compared with Algonquin, Zhongmu 1 did not exhibit a higher alkali tolerance under the Na2CO3-NaHCO3 treatment with the low Na+ concentration (50 mmol L-l). The alkali increased the accumulation of Na+, Ca2+, and Mg2+ in the root and changed the Ca2+ and Mg2+ balance in the entire alfalfa plant. The salt and alkali stresses decreased the K+ and Fe3+ contents of the roots and leaves, the root Mn2+ content, and the shoot Zn2+ content, but they increased the Fe3+ accumulation of the shoots, the shoot and leaf Cu2+ contents, and the leaf Zn2+ content in both alfalfa cultivars. Based on the results obtained under the conditions of this experiment, we found that the salt and alkali stresses reduced the plant growth in both alfalfa cultivars, while the alkali caused a stronger stress than the neutral salt in alfalfa. Thus, we conclude that under hydroponic conditions, the deleterious effects of the alkali on plants are due to the distribution change of some trophic ion balance in the roots, shoots, and leaves of the plants by causing of Na+, CO3^2-, and/or HCO3- stresses.
基金Project (51304047) supported by the National Natural Science Foundation of ChinaProject (20131037) supported by Science and Technology Foundation of Liaoning Province,China
文摘A formula was proposed to calculate the distribution of metal ions quantitatively in chemical reaction system forming hydroxide where precipitation and complex are formed together. The effects of some factors on formation of precipitation and complex were investigated, and the corresponding precipitation rates of zinc, iron (III), aluminum, copper and magnesium were calculated. As a result, it shows that the proposed formula is reliable. By the proposed formula, the existence state of metal ions in hydroxides reaction system with any metal ions can be well described and the effects of some factors on the distribution of metal ions were determined.
基金Supported by National Natural Science Foundation of China under Grant Nos.10575082,10875098the Natural Science Foundation of Gansu Province under Grant No.3ZS061-A25-013the Natural Science Foundation of Northwest Normal University under Grant Nos.NWNU-KJCXGC-03-48 and NWNU-KJCXGC-03-17
文摘In order to investigate the effect of an arbitrary dust size distribution for vortex-like ion distributiondusty plasma,we use a reasonable polynomial-expressed function to represent an arbitrary dust size distribution.Thenumerical results of linear dispersion relation,nonlinear solitary wave amplitude,width and velocity for polynomialexpressed dust size distribution dusty plasma with vortex-like ion distribution have been studied.
基金Supported by the Science and Technology Support Program of Hebei Province(17226913D)the Project for Innovation of Hebei Province(F17R07)
文摘An Asparagus officinalis L. cultivar NJ978 was used to study the growing rate, salt ion content and mineral ion uptake and distribution in plants under salt stress. The results showed that salt stress significantly inhibited seedling growth and there was a negative relationship between seedling growth and salt concentration. The seedlings growth showed no significant decrease under low salt stress (NaCl≤50 mmol/L), while high concentrations of NaCl led to detrimental effects on the growth of A. officinalis L.. With the increase of NaCl concentration, the Na + content increased gradually in A. officinalis L. roots, stems and leaves while the K^+ and Ca^2+ contents had slow decreases. Under low salt stress, the seedlings of A. officinalis L. could prevent Na + from transporting to aerial part by withholding Na + in root, which could keep the balance of ions in aerial part, but under high salt stress (NaCl 〉 100 mmol/L), the aerial part of seedlings accumulated superabundance of Na +, which limited the uptake of K^+ and Ca^2+ , so seedlings were damaged heavily, which manifested as the gradual decrease of K^+/Na + and Ca^2+ /Na + in the roots and aerial part of the seedlings. The selective absorption of K^+, Ca^2+ and Na + (AS K,Na and AS Ca,Na ) was significantly increased with increased salinity, while the selective transportation (TS K,Na and TS Ca,Na ) increased at first and then decreased with the increased salinity. Therefore, the strong ability of salt exclusion and the regionalized distribution of ions in roots, stems and leaves could be one of the salt tolerance mechanisms of A. officinalis L.
基金supported by the National Natural Science Foundation of China (52172159)the Postdoctoral Fellowship Program of CPSF (GZB20230631)。
文摘Aqueous zinc metal batteries (AZMBs) are hindered by uncontrolled dendrites and side reactions during commercialization,despite their advantages of safety and high capacity density.Herein,we propose the electrical feedback strategy to restrain the Zn dendrites resulting from the"tip effect"and optimize interfacial Zn^(2+)distribution to accelerate electrodeposition kinetics by using the lithium niobate (LNO) layer.Specifically,at the bumps of the zinc anode,the ferroelectric LNO is polarized by the locally strong electric field,which in turn counteracts the"tip effect".In this way,the dynamic polarization of LNO can repair the uneven tip electric field to achieve uniform and flat zinc deposition.In addition,owing to the interaction between Nb and Zn^(2+),a higher concentration of Zn^(2+)near the zincophilic LNO@Zn surface is obtained for the rapid electrochemical reaction kinetics of plating.Considering the aforementioned advantages,the LNO@Zn anode harvests stable cycling over 1200 h at 10 mA cm^(-2)with a superior cumulative capacity of 5800 mAh cm^(-2).Assembled with the a-MnO_(2) cathode,the full cell using LNO@Zn anode exhibits the slower capacity decay (0.054%per cycle) during 1000 cycles.This strategy provides a perspective for stabilizing zinc metal anodes through dynamic electrical response and interfacial ion redistribution effect.
基金Ninth-five" National priority project (96-007-01-05): Studies on techniques of selection and breeding of resistant plants in "Sanbei" area of China.
文摘Transpiration rate and ion distribution of pagoda tree, walnut, velvet ash and poplar seedlings treated by NaCl solution of 0, 50, 100, 200 mmol·L-1 were studied. The results showed that there were significant differences in the response to NaCl among the four tree species. Na+ exclusion capacity of pagoda tree was the largest among the four species. The Na+ exclusion capacity of velvet ash was less than that of pagoda tree. Salt excretion capacity of velvet ash was limited. Its salt-tolerance was bigge...
基金The project supported by the Natural Science Foundation of Guangdong province (No. 000675) the Key project tackled of Guangdong province (ZKM01401G)
文摘The ion density distribution in the reaction chamber was diagnosed by a Langmuir probe. The rules of the ion density distribution were obtained under the pressures of 9 Pa, 13 Pa, 27 Pa and 53 Pa in the reaction chamber, different radio-frequency powers and different positions. The result indicates that the ion density decreases as the pressure increases, and increases as the power decreases. The ion density of axial position z =0 achieves 5.8×1010 on the center of coil under the power of 200 w and pressure of 9 Pa in the reaction chamber.
基金supported by the National Natural Science Foundation of China(Grant No.42241143)the pre-research projects on Civil Aerospace Technologies(No.D020104)funded by the China National Space Administration.
文摘The pitch angle distributions of ions and electrons can be affected by various processes;thus,they can serve as an important indicator of the physical mechanisms driving the dynamics of space plasmas.From observations from the Mars Ion and Neutral Particle Analyzer onboard the Tianwen-1 orbiter,we calculated the pitch angle distributions of protons in the Martian induced magnetosphere by using information from the magnetohydrodynamically simulated magnetic field,and we statistically analyzed the spatial occurrence pattern of different types of pitch angle distributions.Even though no symmetrical features were seen in the dataset,we found the dominance of the field-aligned distribution type over the energy range from 188 to 6232 eV.Maps of the occurrence rate showed the preferential presence of a trapped-like distribution at the lower altitudes of the surveyed nightside region.Although our results are more or less restricted by the adopted magnetic field,they indicate the complexity of the near-Mars proton pitch angle distributions and infer the possibility of wave–particle interactions in the Martian induced magnetosphere.
文摘Propellant ionization in the Hall thruster discharge channel is a significant process and has strong influence on the thruster's efficiency. In this work, the functional relation has been established between the ionization density distribution and the function of the ion energy distribution through the basic equations governing the ion flow in the Hall thruster channel and the method achieved for reconstructing the ionization density distribution inside the channel by ordinary plasma diagnosis of the potential distribution and ion energy spectrum of the plasma jet. The ionization density distributions of single and double charged ions in an ATON-thruster channel have been reconstructed according to the experimental data of the potential distribution along the axis of the channel and the ion energy spectrum of the plasma jet. The agreement between the calculation and experimental results of the percentage of double charged ions proves the validity of our method achieved in this work.
基金Project supported by the Important National Science and Technology Specific Project,China(Grant No.2011ZX02403-001)the National Natural Science Foundation of China(Grand No.11675039)the Fundamental Research Funds for the Central Universities,China(Grand No.DUT16LK06)
文摘A retarding field energy analyzer(RFEA) is used to measure the time-averaged ion energy distributions(IEDs) on the substrate in both continuous wave(CW) and synchronous pulse modulated radio-frequency(RF) inductively coupled Ar plasmas(ICPs).The effects of the phase shift θ between the RF bias voltage and the RF source on the IED is investigated under various discharge conditions.It is found that as θ increases from 0 to π,the IED moves towards the low-energy side,and its energy width becomes narrower.In order to figure out the physical mechanism,the voltage waveforms on the substrate are also measured.The results show that as θ increases from 0 to π,the amplitude of the voltage waveform decreases and,meanwhile,the average sheath potential decreases as well.Specifically,the potential drop in the sheath on the substrate exhibits a maximum value at the same phase(i.e.,θ = 0) and a minimum value at the opposite phase(i.e.,θ = π).Therefore,when ions traverse across the sheath region above the substrate,they obtain less energies at lower sheath potential drop,leading to lower ion energy.Besides,as θ increases from π to 2π,the IEDs and their energy widths change reversely.
文摘Resonance lines are extensively used to diagnose electronic temperature Te and ions distribution. However, the analysis of the x-ray spectroscopy emitted from plasmas produced by a ns laser Jsually needs the help of a code or some assumptions. In this paper, a diagnostic idea of using line-pairs emitted from a doubly-excited state is proposed. By using the method presented in this paper, Te and the fractional population ratio of bare nuclei and H-like ions are directly obtained from the emission intensity ratios.
基金financial supports by National Natural Science Foundation of China(Nos.11975163 and 12175160)Nantong Basic Science Research-General Program(No.JC22022034)Natural Science Research Fund of Jiangsu College of Engineering and Technology(No.GYKY/2023/2)。
文摘This study delves into ion behavior at the substrate position within RF magnetron discharges utilizing an indium tin oxide(ITO)target.The positive ion energies exhibit an upward trajectory with increasing RF power,attributed to heightened plasma potential and initial emergent energy.Simultaneously,the positive ion flux escalates owing to amplified sputtering rates and electron density.Conversely,negative ions exhibit broad ion energy distribution functions(IEDFs)characterized by multiple peaks.These patterns are clarified by a combination of radiofrequency oscillation of cathode voltage and plasma potential,alongside ion transport time.This elucidation finds validation in a one-dimensional model encompassing the initial ion energy.At higher RF power,negative ions surpassing 100 e V escalate in both flux and energy,posing a potential risk of sputtering damages to ITO layers.
基金Supported by the Shanghai Key Lab of Modern Optical System
文摘In the context of unified hydrodynamics, we discuss the pseudorapidity distributions of the charged particles produced in Au-Au and Cu-Cu collisions at the low RHIC energies of √SNN = 19.6 and 22.4 GeV, respectively. It is found that the unified hydrodynamics alone can give a good description to the experimental measurements. This is different from the collisions at the maximum RHIC energy of √SNN = 200 GeV or at LHC energy of √SNN= 2.76 TeV, in which the leading particles must be taken into account so that we can properly explain the experimental observations.
文摘To investigate the effect of the rib structure on the discharge characteristics of the plasma display panel, the potential distribution, particles density distribution and ions incident angle distribution were examined by simulation of a two-dimensional particle-in-cell/Monte Carlo collision, with two kinds of rib structure: the stripe rib structure and the Waffle rib structure. The results showed that the distribution of electric potential at the corner of the discharge cell was almost the same for these two rib structures while in the centre there was a difference between these two rib structures. The striation phenomenon could be observed in both cases. The distribution of density also indicated that the striation phenomenon was accompanied by the firing of discharge, and the Waffle rib structure might reduce the density humps. In the cell with a stripe rib structure, the profiles of the surface charge density along the sustained dielectric layer presented a better fluctuating distribution than that in the cell with a Waffle rib structure. The spatial potential and particle density in the discharge bulk showed that the Waffle ribs could weaken the striation phenomenon, which could be explained by the decrease in the particle numbers in the discharge cell. The simulation results of the ion incident angle showed that most ions impacted the sustained dielectric layer in the normal stripe rib cell with an incident angle in the range of 6° to 19° while with the Waffle rib structure the incident angle of most ions was in the range of 4° to 19°. The Waffle rib structure did not affect the angle distribution of incident ions significantly.
基金The authors are grateful for the financial support by the Postdoctoral Science Foundation of China (No. 2003034330)the Science Foundation for mld-youth elite of Shandong Province+3 种基金the Nature Science Foundation of Shandong Province (No. Y2005F11 and No. 2005BS11010)the Nature Science Foundation of Yantai Normal University (No. 032912, 20052901, 042920) Educational Project for Postgraduate of Yantai Normal University (No. YD05001)Applied Project of Educational Bureau of Shandong Province (No. J05D03, J04B02).
文摘Several of new chelating resins containing sulfoxide and heterocyclic functional groups (3-aminopyridine and 2-mercaptobenzothiazole) based on macroporous chloromethylated polystyrene were synthesized and characterized by elemental analysis and infrared spectra. Their adsorption capacities towards Zn^2+, Cu^2+, Pb^2+, Hg^2+ and Ag^+ at pH 3.0 and 6.0 were investigated in detail. It was found that the adsorption capacities of the resins containing bis[(3-pyridylaminoethyl)sulfoxide or (2-benzothiazolylthioethyl)sulfoxide for the above ions were higher than that on ones containing single above-mentioned groups.
基金This work was supported by the Fundamental Research Funds for the Central Universities (No.2017JBM003), the National Natural Science Foundation of China (No.61575053, No.61504008), and the Specialized Research Fund for the Doctoral Program of Higher Education of China (No.20130009120042).
文摘Lithium ion battery has typical character of distributed parameter system, and can be described precisely by partial differential equations and multi-physics theory because lithium ion battery is a complicated electrochemical energy storage system. A novel failure prediction modeling method of lithium ion battery based on distributed parameter estimation and single particle model is proposed in this work. Lithium ion concentration in the anode of lithium ion battery is an unmeasurable distributed variable. Failure prediction system can estimate lithium ion concentration online, track the failure residual which is the difference between the estimated value and the ideal value. The precaution signal will be triggered when the failure residual is beyond the predefined failure precaution threshold, and the failure countdown prediction module will be activated. The remaining time of the severe failure threshold can be estimated by the failure countdown prediction module according to the changing rate of the failure residual. A simulation example verifies that lithium ion concentration in the anode of lithium ion battery can be estimated exactly and effectively by the failure prediction model. The precaution signal can be triggered reliably, and the remaining time of the severe failure can be forecasted accurately by the failure countdown prediction module.
基金supported by National Natural Science Foundation of China(No.11805275)Hunan Provincial Natural Science Foundation of China(No.2018JJ3592)。
文摘Non-intrusive characterization of the singly ionized xenon velocity in Hall thruster plume using laser induced fluorescence(LIF)is critical for constructing a complete picture of plume plasma,deeply understanding the ion dynamics in the plume,and providing validation data for numerical simulation.This work presents LIF measurements of singly ionized xenon axial velocity on a grid ranging from 100 to 300 mm in axial direction and from 0 to 50 mm in radial direction for a600 W Hall thruster operating at the nominal condition of discharge voltage 300 V and discharge current 2 A,the influence of discharge voltage is investigated as well.The ion velocity distribution function(IVDF)results in the far-field plume demonstrate a profile of bimodal IVDFs,especially prominent at radial distances greater than channel inner radius of 22 mm at axial position of 100 mm,which is quite different from that of the near-field plume where bimodal IVDFs occur in the central core region for the same power Hall thruster when compared to previous LIF measurements of BHT-600 by Hargus(2010 J.Propulsion Power 26135).Beyond 100 mm,only single-peak IVDFs are measured.The two-dimensional ion velocity vector field indicates the bimodal axial IVDF is merely a geometry effect for the annular discharge channel in the far-field plume.Results about the IVDF,the most probable velocity and the accelerating potential profile along the centerline all indicate that ions are still accelerating at axial distances greater than 100 mm,and the maximum most probable velocity measured at300 mm downstream of the exit plane is about 19 km s-1.In addition,the most probable velocity of ions along radial direction changes a little except the lower velocity ion populations in the bimodal IVDF cases.The ion temperature at axial distances of 10 and 300 mm oscillates along the radial direction,while the ion temperature first increases,and then decreases for the 200 mm case.Finally,the axial position for the ion peak axial velocity on the thruster centerline is shifted upstream for higher discharge voltages,and the velocity curve is becoming steeper with the discharge voltage before reaching the maximum.This observation can be used as a criterion to optimize the thruster performance.
基金Project supported by the National Natural Science Foundation of China(Grant No.11274219)the Science and Technology Planning Project of Guangdong Province of China(Grant No.180917124960522)the Program for Promotion of Science at Universities in Guangdong Province of China(Grant No.2018KTSCX062)。
文摘Recently,the quantitative rescattering model(QRS)for nonsequential double ionization(NSDI)is modified by taking into account the potential change(PC)due to the presence of electric field at the time of recollision.Using the improved QRS model,we simulate the longitudinal momentum distributions of doubly charged ions He2+by projecting the correlated two-electron momentum distributions for NSDI of He onto the main diagonal.The obtained results are compared directly with the experimental data at different intensities.It is found that when the PC is considered,the width of momentum distributions reduces and the agreement between theory and experiment is improved.
基金Project supported by the National Science and Technology Ministry (Nos.2006BAD09A08-03-01 and 2006BAD09A04-05)the National High Technology Research and Development Program (863 Program) of China (No.2007AA091702)the Opening Program of Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresource and Environmental Protection (JLCBE) (No.JLCBE07001).
文摘A hydroponic experiment with six treatments, i.e., 0% seawater (control), 10% seawater, 25% seawater, 0% seawater + N (7.5 mmol L-1 NaNO3), 10% seawater + N (7.5 mmol L-1 NaO3), and 25% seawater + N (7.5 mmol L-1 NaNO3), was carried out to study the effect of nitrogen addition on the growth and physiological and biochemical characteristics of Jerusalem artichoke (Helianthus tuberosus) seedlings under seawater stress. The 10% seawater stress treatment had the least effect on plant growth while at 25% seawater growth was significantly inhibited. The malondialdehyde content and electrolyte leakage in leaves under 10% seawater were similar to those of the control, but significantly higher under the 25% seawater stress. The activities of superoxide dismutase, peroxidase and catalase in the leaves increased concomitantly with increasing seawater concentration and time. Proline and soluble-sugars in the leaves and Na^+, K^+, and Cl- contents in shoots and roots increased significantly with the concentration of seawater increasing. Nitrogen addition resulted in increasing fresh and dry weights of shoots and roots compared with seawater treatment without N. Nitrogen supplementation also significantly enhanced the activities of antioxidant enzymes in leaves. Addition of N to seawater enhanced the contents of proline and soluble-sugars in the leaves and K^+ and total-N in the aerial parts and roots of H. tuberosus, but it resulted in declined concentrations of Na^+ and Cl- in the aerial parts and roots. Nitrogen addition ameliorated the toxicity of seawater by improving the antioxidative enzymes, accumulating of proiine and soluble-sugars, and altering the distribution of inorganic ions in H. tuberosus.