Localized wave solutions and interactions of the (2+1)-dimensional Hirota-Satsuma-Ito equation

This paper studies the(2+1)-dimensional Hirota-Satsuma-Ito equation.Based on an associated Hirota bilinear form,lump-type solution,two types of interaction solutions,and breather wave solution of the(2+1)-dimensional Hirota-Satsuma-Ito equation are obtained,which are all related to the seed solution of the equation.It is interesting that the rogue wave is aroused by the interaction between one-lump soliton and a pair of resonance stripe solitons,and the fusion and fission phenomena are also found in the interaction between lump solitons and one-stripe soliton.Furthermore,the breather wave solution is also obtained by reducing the two-soliton solutions.The trajectory and period of the one-order breather wave are analyzed.The corresponding dynamical characteristics are demonstrated by the graphs.

Bifurcations, Analytical and Non-Analytical Traveling Wave Solutions of (2 + 1)-Dimensional Nonlinear Dispersive Boussinesq Equation

For the (2 + 1)-dimensional nonlinear dispersive Boussinesq equation, by using the bifurcation theory of planar dynamical systems to study its corresponding traveling wave system, the bifurcations and phase portraits of the regular system are obtained. Under different parametric conditions, various sufficient conditions to guarantee the existence of analytical and non-analytical solutions of the singular system are given by using singular traveling wave theory. For certain special cases, some explicit and exact parametric representations of traveling wave solutions are derived such as analytical periodic waves and non-analytical periodic cusp waves. Further, two-dimensional wave plots of analytical periodic solutions and non-analytical periodic cusp wave solutions are drawn to visualize the dynamics of the equation.

MULTIPLICITY OF NORMALIZED SOLUTIONS FOR THE FRACTIONAL SCHR?DINGER-POISSON SYSTEM WITH DOUBLY CRITICAL GROWTH

In this paper,we are concerned with solutions to the fractional Schrodinger-Poisson system■ with prescribed mass ∫_(R^(3))|u|^(2)dx=a^(2),where a> 0 is a prescribed number,μ> 0 is a paremeter,s ∈(0,1),2 <q <2_(s)^(*),and 2_(s)^(*)=6/(3-2s) is the fractional critical Sobolev exponent.In the L2-subcritical case,we show the existence of multiple normalized solutions by using the genus theory and the truncation technique;in the L^(2)-supercritical case,we obtain a couple of normalized solutions by developing a fiber map.Under both cases,to recover the loss of compactness of the energy functional caused by the doubly critical growth,we need to adopt the concentration-compactness principle.Our results complement and improve upon some existing studies on the fractional Schrodinger-Poisson system with a nonlocal critical term.

Efficient removal of Al(Ⅲ)and P507 from high concentration MgCl_(2)solution based on in-situ reaction strategy

For a highly efficient recycling of a wastewater containing a high concentration of MgCl_(2),Al(Ⅲ)and P507 were scheduled to be removed in advance.In this study,the in-situ removal of Al(Ⅲ)and P507 from a high concentration MgCl_(2)solution at different pH values and Al/P molar ratios was investigated.The results showed that P507 formed organic complexes of Al_(x)(OH)_y^(Z+)-P507 at pH of 2.0-4.0.At pH of 4.0-5.0,Al(Ⅲ)precipitated and transferred into Al(OH)_(3)with a flocculent amorphous morphology.Active sites on the Al(OH)_(3)surface enhanced the removal efficiency of P507.At pH of 6.0-6.5,Al(Ⅲ)and Mg(Ⅱ)formed layered crystalline Al(OH)_(3)and MgAl_(2)(OH)_(8with)small pore channels and fewer active sites,resulting in a reduced removal efficiency of P507.When the Al/P molar ratio exceeded 13 and the pH was between 4.0 and 5.0,the removal rates of both Al(Ⅲ)and P507 were higher than98%,while the concentration loss of Mg(Ⅱ)was only 0.2%-0.9%.

Extending the solid solution range of sodium ferric pyrophosphate:Off‐stoichiometric Na_(3)Fe(2.5)(P_(2)O_(7))_(2)as a novel cathode for sodium‐ion batteries

Iron‐based pyrophosphates are attractive cathodes for sodium‐ion batteries due to their large framework,cost‐effectiveness,and high energy density.However,the understanding of the crystal structure is scarce and only a limited candidates have been reported so far.In this work,we found for the first time that a continuous solid solution,Na_(4−α)Fe_(2+α)_(2)(P_(2)O_(7))_(2)(0≤α≤1,could be obtained by mutual substitution of cations at center‐symmetric Na3 and Na4 sites while keeping the crystal building blocks of anionic P_(2)O_(7) unchanged.In particular,a novel off‐stoichiometric Na_(3)Fe(2.5)(P_(2)O_(7))_(2)is thus proposed,and its structure,energy storage mechanism,and electrochemical performance are extensively investigated to unveil the structure–function relationship.The as‐prepared off‐stoichiometric electrode delivers appealing performance with a reversible discharge capacity of 83 mAh g^(−1),a working voltage of 2.9 V(vs.Na^(+)/Na),the retention of 89.2%of the initial capacity after 500 cycles,and enhanced rate capability of 51 mAh g^(−1)at a current density of 1600 mA g^(−1).This research shows that sodium ferric pyrophosphate could form extended solid solution composition and promising phase is concealed in the range of Na_(4−α)Fe_(2+α)_(2)(P_(2)O_(7))_(2),offering more chances for exploration of new cathode materials for the construction of high‐performance SIBs.

CO2 Transformation at Controlled Temperature with Lithium Hydroxide Solution and Metallic Lithium

This paper presents a study on CO2 atmospheric transformation which was reacted directly with lithium hydroxide solution and metallic lithium. This solution was obtained through the reaction between metallic lithium and deionized water where hydrogen is produced and by exposing the metal at ambient conditions. In the transformation process, atmospheric CO2 gas reacts directly with LiOH solution, in both cases, the CO2 transformation kinetics was different. For this purpose, reactions between CO2 and LiOH solution were carried out under controlled temperature and the second process only with metallic lithium, which was exposed at room temperature, however, in these two processes lithium carbonate oxide was formed and identified. According to the results, the efficiency in CO2 transformation is a function of temperature value which was variable until completely obtaining the by-product, its XRD characterization indicated the formation only of Li2CO3 in both procedures. Under laboratory conditions lithium compounds selectively reacted with CO2. In the same way, there is an alternative procedure to obtain LiOH and Li2CO3 for different applications in various areas.

Interaction solutions and localized waves to the(2+1)-dimensional Hirota-Satsuma-Ito equation with variable coefficient

This article investigates the Hirota-Satsuma-Ito equation with variable coefficient using the Hirota bilinear method and the long wave limit method.The equation is proved to be Painlevé integrable by Painlevé analysis.On the basis of the bilinear form,the forms of two-soliton solutions,three-soliton solutions,and four-soliton solutions are studied specifically.The appropriate parameter values are chosen and the corresponding figures are presented.The breather waves solutions,lump solutions,periodic solutions and the interaction of breather waves solutions and soliton solutions,etc.are given.In addition,we also analyze the different effects of the parameters on the figures.The figures of the same set of parameters in different planes are presented to describe the dynamical behavior of solutions.These are important for describing water waves in nature.

Exact Traveling Wave Solutions to Phi-4 Equation and Joseph-Egri (TRLW) Equation and Calogro-Degasperis (CD) Equation by Modified (G'/G2)-Expansion Method

In this study, we will introduce the modified (G'/G2)-expansion method to explore some of the exact traveling wave solutions of some nonlinear partial differential equations namely, Phi-4 equation, Joseph-Egri (TRLW) equation, and Calogro-Degasperis (CD) equation. As a result, we have obtained solutions for the equations expressed in terms of trigonometric, hyperbolic and rational functions. Moreover, some selected solutions are plotted using some specific values for the parameters.

2T-PERIODIC SOLUTION FOR m ORDER NEUTRAL TYPEDIFFERENTIAL EQUATIONS WITH TIME DELAYS

Periodic solution of m order linear neutral equations with constant coefficient and time delays was studied. Existence and uniqueness of 2 T-periodic solutions for the equation were discussed by using the method of Fourier series. Some new necessary and sufficient conditions of existence and uniqueness of 2 T-periodic solutions for the equation are obtained. The main result is used widely. It contains results in some correlation paper for its special case, improves and extends the main results in them. Existence of periodic solution for the equation in larger number of particular case can be checked by using the result, but cannot be checked in another paper. In other words, the main result in this paper is most generalized for (1) the better result cannot be found by using the same method.

Removal of S^(2-) ion from sodium aluminate solutions with sodium ferrite

The synthesis of sodium ferrite and its desulfurization performance in S2 -bearing sodium aluminate solutions were investigated. The thermodynamic analysis shows that the lowest temperature is about 810 K for synthesizing sodium ferrite by roasting the mixture of ferric oxide and sodium carbonate. The results indicate that the formation process of sodium ferrite can be completed at 1173 K for 60 min, meanwhile raising temperature and reducing NazCO3 particle size are beneficial to accelerating the formation of sodium ferrite. Sodium ferrite is an efficient desulfurizer to remove the S2- in aluminate solution, and the desulfurization rate can reach approximately 70% at 373 K for 60 min with the molar ratio of iron to sulfur of 1：1-1.5：1. Furthermore, the desulfurization is achieved by NaFeS2·2H2O precipitation through the reaction of Fe（OH）4 and S^2- in aluminate solution, and the desulfurization efficiency relies on the Fe（OH）4^- generated by dissolving sodium ferrite.

CeO_(2)-Ps-LaCoO_(3)/Al_(2)O_(3)的制备及其对高浓度有机废水的臭氧催化降解研究

为有效降解高浓度造纸废水有机物,通过电化学沉积法分别在磷酸盐中性缓冲溶液和纯水中制得CeO_(2)-Ps-LaCoO_(3)/Al_(2)O_(3)和CeO_(2)-LaCoO_(3)/Al_(2)O_(3)。通过对CeO_(2)-Ps-LaCoO_(3)/Al_(2)O_(3)、CeO_(2)-LaCoO_(3)/Al_(2)O_(3)以及LaCoO_(3)/Al_(2)O_(3)进行XRD、SEM、析氧过电位和电阻抗等物性表征发现,CeO_(2)-Ps-LaCoO_(3)/Al_(2)O_(3)具有更强催化氧化性及稳定性。对高浓度造纸废水臭氧催化氧化降解3 h后,CeO_(2)-Ps-LaCoO_(3)/Al_(2)O_(3)对废水COD的降解率为76.5%,而相同条件下CeO_(2)-LaCoO_(3)/Al_(2)O_(3)和LaCoO_(3)/Al2O_(3)的化学需氧量(COD)降解率分别为68.5%和63.5%。

CaCl_(2)和MgCl_(2)及其复合溶液制备α-半水石膏

为提高磷石膏的利用率和附加值,采用常压水热合成法以磷石膏为主要原材料制备α-半水石膏材料,主要研究不同质量分数的CaCl_(2)、MgCl_(2)及其复合溶液对磷石膏常压水热制备α-半水石膏脱水速率、物相组成和微晶形貌的影响。研究发现,磷石膏在95℃的CaCl_(2)溶液、MgCl_(2)溶液及CaCl_(2)-MgCl_(2)复合溶液中均可脱水转晶生成α-半水石膏。在CaCl_(2)溶液和MgCl_(2)溶液中,随着盐溶液浓度的增加,α-半水石膏的生成速率加快,其中经质量分数为35%的CaCl_(2)溶液反应4 h后或质量分数为25%的MgCl_(2)溶液反应1 h后,磷石膏可完全反应成α-半水石膏。在CaCl_(2)-MgCl_(2)复合溶液中,随着MgCl_(2)溶液浓度的增加,磷石膏的脱水转化速率逐渐加快,当CaCl_(2)质量分数≤19%和MgCl_(2)质量分数≥11%时,磷石膏水热反应1 h即可形成颗粒分布较为完整的α-半水石膏。

时效处理对Cu-Y_(2)O_(3)-Ti复合材料组织及性能的影响

以Cu、Y、Ti和CuO粉末为原料,采用机械合金化(MA)和热还原的方法制备了Cu-Y_(2)O_(3)-Ti复合粉末。然后经放电等离子烧结(SPS)技术制备了Cu-Y_(2)O_(3)-Ti复合材料,并对材料进行了900℃固溶1 h和不同温度时效2 h的处理。采用光学显微镜(OM)、扫描电镜(SEM)、X射线衍射仪(XRD)、能谱仪(EDS)、拉伸试验和导电率测量仪等研究了不同温度时效处理对Cu-Y_(2)O_(3)-Ti复合材料组织及性能的影响。结果表明:随着时效温度的升高,Cu-Y_(2)O_(3)-Ti复合材料的晶粒和第二相尺寸增大,导电率降低,最大应变和抗拉强度先增大后减小。Cu-Y_(2)O_(3)-Ti复合材料经900℃固溶1 h+400℃时效2 h后,综合性能最优,其具有良好塑性的同时,抗拉强度和导电率分别达到326.4 MPa和73.0%IACS。

新标09CrCuSb耐酸钢的耐50%H_(2)SO_(4)腐蚀性能

通过电化学测试和全浸腐蚀试验,研究了不同温度(25,50,60,70℃)条件下新标09CrCuSb耐酸钢在50%H_(2)SO_(4)溶液中的腐蚀行为。结果表明:随着温度从25℃升至70℃,新标09CrCuSb钢的腐蚀速率整体呈现增大趋势,在70℃时,腐蚀速率达到最高,为2.70 g/(m^(2)·h),这与随温度升高,腐蚀产物中具有保护性作用的Fe_(3)O_(4)含量减少,无保护作用的FeSO_(4)·H_(2)O含量增加以及锈层中微孔变化有关。另外,由于新标调整了09CrCuSb钢中Cu、Mo、Sn、Sb、W等元素的含量,与旧标09CrCuSb钢相比,阳极维钝电流密度J维钝降低,同等温度条件下,新标09CrCuSb钢的耐蚀性得到较大改善。

SLC3A2在慢性阻塞性肺病中的表达及其与炎症的关系

目的:探讨溶质转运载体家族3成员2(SLC3A2)在慢性阻塞性肺病(COPD)发生机制中的作用。方法:收集72例COPD稳定期患者纳入COPD组,另选取67例同期健康体检者为对照组。采集2组外周静脉血,通过密度梯度离心和红细胞裂解的方法分离出中性粒细胞,采用蛋白免疫印迹法检测外周血中性粒细胞SLC3A2水平,酶联免疫吸附(ELISA)法检测血浆中白介素(IL)-8水平,同时收集2组的肺功能指标,包括第1秒用力呼气容积(FEV_(1))、用力肺活量(FVC)。分析SLC3A2与IL-8、FEV_(1)/FVC、FEV_(1)%预计值的相关性。结果:COPD组外周血中性粒细胞的SLC3A2及IL-8水平高于对照组(P均<0.01),SLC3A2与IL-8呈正相关(r=0.45,P<0.01),与FEV_(1)/FVC、FEV_(1)%预计值呈负相关(r=-0.42,-0.45,P均<0.01)。结论:SLC3A2可能通过炎症反应参与COPD的发生,SLC3A2有可能成为COPD临床的炎症标志物和治疗的靶点。

弱碱性吸收剂碳捕集及CO_(2)富液生物再生性能

碳捕集转化一体化工艺能利用CO_(2)转化过程同步实现CO_(2)富液再生,有望降低碳捕集转化整体成本。为评价生物甲烷化与碳捕集耦合的可行性,首先,在填料塔中考察了以4.2 g/L NaHCO_(3)、6 g/L Na_(2)CO_(3)、微生物营养液配制的弱碱性吸收剂(pH=10)对模拟烟气中CO_(2)的吸收性能;其次,在厌氧瓶内利用生物甲烷化过程对CO_(2)富液开展5个周期的循环再生试验。结果表明,填料塔气体流量≤1.0 L/min时,随液体流量增加,所有试验组CO_(2)去除率逐渐上升并能稳定在80%以上,该填料塔液体流量宜≤0.9 L/min;不同气体流量(0.4~1.2 L/min)下填料塔体积总传质系数基本稳定在17~19 mol/(h·kPa·m^(3));CO_(2)吸收导致吸收液中NaHCO_(3)增加、Na_(2)CO_(3)减少,二者变量比值在1.2~1.9。气体流量为0.6 L/min、液体流量为0.7 L/min时,在维持80%以上CO_(2)去除率的前提下,该弱碱性吸收剂可循环使用6次,此时活性组分CO_(3)^(2-)利用率达89.5%,形成的CO_(2)富液中总无机碳量为0.127 mol/L,pH为8.82,能为生物甲烷化微生物提供适宜的生长环境。CO_(2)富液循环生物再生试验表明,每次再生后的吸收剂CO_(2)吸收量基本稳定在69.6~78.6 mmol/L,且再生期间CH 4产生过程具有良好的重复性;再生试验后,Firmicutes、Actinobacteriota等耐碱性门水平细菌得到一定富集;氢营养型产甲烷菌在再生前后古菌属中占比均接近99%,但再生试验期间弱碱性环境导致Methanobrevibacter相对丰度降低了19.5%,unclassified_f_Methanobacteriaceae增加了18.7%。初步证实了碳捕集耦合生物甲烷化工艺的可行性。

Modified (2+1)-dimensional displacement shallow water wave system and its approximate similarity solutions

Recently, a new （2＋1）-dimensional shallow water wave system, the （2＋1）-dlmenslonal displacement shallow water wave system （2DDSWWS）, was constructed by applying the variational principle of the analytic mechanics in the Lagrange coordinates. The disadvantage is that fluid viscidity is not considered in the 2DDSWWS, which is the same as the famous Kadomtsev-Petviashvili equation and Korteweg-de Vries equation. Applying dimensional analysis, we modify the 2DDSWWS and add the term related to the fluid viscidity to the 2DDSWWS. The approximate similarity solutions of the modified 2DDSWWS （M2DDSWWS） is studied and four similarity solutions are obtained. For the perfect fluids, the coefficient of kinematic viscosity is zero, then the M2DDSWWS will degenerate to the 2DDSWWS.

The Travelling Wave Solutions for （2＋1）-dimensional AKNS Equation

Based on the travelling wave method, a(2 + 1)-dimensional AKNS equation is considered. Elliptic solution and soliton solution are presented and it is shown that the soliton solution can be reduced from the elliptic solution. It also proves that the result is consistent with the soliton solution of simplify Hirota bilinear method by Wazwaz and illustrate the solution are right travelling wave solution.

SnO_2-based solid solutions for CH_4 deep oxidation: Quantifying the lattice capacity of SnO_2 using an X-ray diffraction extrapolation method

A series of SnO2‐based catalysts modified by Mn, Zr, Ti and Pb oxides with a Sn/M （M=Mn, Zr, Ti and Pb） molar ratio of 9/1 were prepared by a co‐precipitation method and used for CH4 and CO oxidation. The Mn3＋, Zr4＋, Ti4＋and Pb4＋cations are incorporated into the lattice of tetragonal rutile SnO2 to form a solid solution structure. As a consequence, the surface area and thermal stability of the catalysts are improved. Moreover, the oxygen species of the modified catalysts become easier to be reduced. Therefore, the oxidation activity over the catalysts was improved, except for the one modified by Pb oxide. Manganese oxide demonstrates the best promotional effects for SnO2. Using an X‐ray diffraction extrapolation method, the lattice capacity of SnO2 for Mn2O3 was 0.135 g Mn2O3/g SnO2, which indicates that to form stable solid solution, only 21%Sn4＋cations in the lattice can be maximally replaced by Mn3＋. If the amount of Mn3＋cations is over the capacity, Mn2O3 will be formed, which is not favorable for the activity of the catalysts. The Sn rich samples with only Sn‐Mn solid solution phase show higher activity than the ones with excess Mn2O3 species.

Separation of ionic liquids from dilute aqueous solutions using the method based on CO_2 hydrates

Ionic liquids （ILs） have been regarded as the potential novel solvents for improved analytical- and process-scale separation methods.The development of methods for the recovery of ILs from aqueous solutions to escape contamination and recycle samples will ultimately govern the viability of ILs in the future industrial applications. Therefore, in this paper a new method for separation of ILs from their dilute aqueous solutions and simultaneously purification of water was proposed on the basis of the CO2 hydrate formation. For illustration, the dilute aqueous solutions with concentrations of ILs ranging from 2× 10^-3 mol% to 2×10^-1 mol% were concentrated. The results show that the separation efficiency is very impressive and that the new method is applicable to aqueous solutions of both hydrophobic and hydrophilic ILs. Compared to the literature separation method based on the supercritical CO2, the new method is applicable to lower concentrations, and more importantly, its operation condition is mild.