Investigation of disused artificial zeolite on the properties of metakaolin-based geopolymer

Artificial zeolite deactivated after repeated utilization and the properties compromised formed disused zeolite. In the past, disused artificial zeolite landfilled after incineration and results in environmental pollution and resource waste. This work synthesized a new type of a new metakaolin-based geopolymer prepared by using disused artificial zeolite and metakaolin. The influence of disused artificial zeolite on the performance and pore structure of the final products was investigated. The bulk density and compressive strength of the samples were approximate 457 kg/m³ and 1.3 MPa, respectively. Moreover, disused artificial zeolite has good mesoporosity and strong foaming performance. The incorporation of disused artificial zeolite generated more pores with smaller diameters and pronounced pore grading, adjust the pore structure of the samples, forming multiscale pore structured structures. This study described one application method of disused artificial zeolite in geopolymers, synthesized a new metakaolin-based geopolymer, which is significant for exploring the potential utilization value of disused artificial zeolite.     

THERMODYNAMICS ADSORPTION OF MANGANESE ION ON 1-（2-PYRIDYLAZO）-2-NAPHTHOL-6-SULPHONIC ACID IMPREGNATED RESIN

An ion-exchange resin of type 201×7 was impregnated with the reagent 1-（2-Pyridylazo）-2-naphthol-6-sulphonic Acid （PAN-S）. The adsorption characteristics of PAN-S resin for manganese ion were studied on the static equilibrium adsorption. Within temperature range of 288K-313K and the concentration range investigated, equilibrium data for the adsorption of manganese ions from aqueous solutions by PAN-S resin were obtained and correlated with Freundlich and Langmuir equation. The results showed that the process of the adsorption of manganese ions from aqueous solution by PAN-S was an exothermic process. Estimations of the isothermic enthalpy change of adsorption, free energy change and entropy of adsorption are reported, and the adsorption behaviors are reasonably interpreted.     

固相萃取-超高效液相色谱-三重四级杆串联质谱法测定水中4种杀菌剂

建立了固相萃取-超高效液相色谱-三重四级杆串联质谱方法检测水中4种杀菌剂(嘧菌酯、戊唑醇、吡唑醚菌酯、肟菌酯). 水样中的杀菌剂经HLB固相萃取柱富集后,使用C18色谱柱分离,以高效液相色谱-串联质谱(HPLC-MS/MS)外标法定量分析. 同时考察pH值、洗脱溶剂、洗脱量等对杀菌剂萃取效果的影响. 试验结果表明,4种化合物在0.10~50.0 μg/L浓度范围内具有较好的线性关系,检出限在0.004~0.095 μg/L之间,回收率为68.7%~95.4%,相对标准偏差(n=5)低于10%. 方法操作简单、快速、准确、灵敏度高,适用于水中4种杀菌剂的定量分析.     

Phase synchronization between nonlinearly coupled Rössler systems

Phase synchronization between nonlinearly coupled systems with 1：1 and 1：2 resonances is investigated. By introducing a concept of phase for a chaotic motion, it is demonstrated that for different internal resonances, with relatively small parameter epsilon, the difference between the mean frequencies of the two sub-oscillators approaches zero. This implies that phase synchronization can be achieved for weak interaction between the two oscillators. With the increase in coupling strength, fluctuations of the frequency difference can be observed, and for the primary resonance, the amplitudes of the fluctuations of the difference seem much smaller compared to the case with frequency ratio 1：2, even with the weak coupling strength. Unlike the enhanced effect on synchronization for linear coupling, the increase in nonlinear coupling strength results in the transition from phase synchronization to a non-synchronized state. Further investigation reveals that the states from phase synchronization to non-synchronization are related to the critical changes of the Lyapunov exponents, which can also be explained with the diffuse clouds.     

Inhibition of radiation degradation of polyolefins by hydroaromatics

Heavy hydroaromatics from petroleum (HHAP) which has evident inhibiting ability toward deterioration of hydrocarbon oils was added to high density polyethylene (PE) and isotactic polypropylene (PP), and the additive effects were examined. After the confirmation of the prominent effects to thermal oxidation of PE and PP, the additive effects to radiation degradation were tested by γ-ray and electron beam irradiations in air. The addition of HHAP was obviously effective in radiation degradation, and the crosslinking of PE was distinctly suppressed by HHAP.     

Oblique indentation of creeping solids

Oblique indentation of power law creeping solids at plane strain conditions is examined with rigid-perfectly plastic material behaviour emerging as an asymptotic case. Indenter profiles are dealt with in general circumstances and represented by homogeneous functions. The core of the method developed draws on self-similarity and is based on an intermediate flat die solution. By this approach the problem of a moving contact boundary may be suppressed and the ensuing procedure becomes independent of loading, geometry, history and time. A computational method, based on the reduced procedure, is developed to obtain high accuracy solutions based on finite elements and applicable to non-linear elasticity. The originally stated problem is then solved subsequently by simple cumulative superposition and results given as a function of impression depth. The relation between contact depth and area is found to be invariant and only dependent on the power law exponent, the amount of friction, the profile and the angle of inclination of the indenter. Detailed results are given for local states of stress and deformation for flat and cylindrical dies at variation of the remaining three stated parameters. The presence of local stick and slip is given due attention and global relations between loading and indentation depth and contact area discussed for practical applications. The fundamental framework laid down may be applied to structural assemblies, joints and seals and diverse applications as flattening of rough surfaces, compaction of powder aggregates and ice-offshore structure interaction.     

奇偶q相干态的高阶反聚束效应

本文研究了奇偶q相干态的高阶反聚束效应,结果表明,当参数q和r²在一定范围内取值时,奇偶q相干态都能呈现出高阶反聚束效应(N≥2),而且2n+1阶的反聚束效应和2n阶的反聚束效应相同。     

关于边数给定图按无符号拉普拉斯谱半径排序的注记

设$k$是正整数, $G$是一个边数给定的简单无向图, 其边数$m\ge 2k$, 最大度$\Delta(G)\le m-k$, 本文给出了图$G$的无符号拉普拉斯谱半径$q(G)$的一个上界. 对边数为$m\ge 8$的两个连通图$G_1$和$G_2$, 利用这个上界我们证明了一个排序定理: 如果$\Delta(G_1)>\Delta(G_2)+1$ 且 $\Delta(G_1)\ge \frac{m}{2}+2$, 那么$q(G_1)>q(G_2)$. 对于不含三角形的图, 我们得到两个更强的结果. 作为上述排序定理的一个应用, 我们完全刻画了无符号拉普拉斯谱半径最大的围长为$c$的$m$边图, 其中$m\ge \max\{ 2c, c+9\}$, 部分解决了陈雯雯等人在[Linear Algebra Appl. 645(2022)123-136]上提出的一个公开问题.