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1.
The discharge of diverse pollutants has led to a complex water environment and posed a huge health threat to humans and animals. Self-propelled micromotors have recently attracted considerable attention for efficient water remediation due to their strong localized mass transfer effect. However, a single functionalized component is difficult to tackle with multiple contaminants and requires to combine different decontamination effects together. Here, we introduced a multifunctional micromotor to implement the adsorption and degradation roles simultaneously by integrating the poly(aspartic acid) (PASP) adsorbent with a MnO2-based catalyst. The as-prepared micromotors are well propelled in contaminated waters by MnO2 catalyzing hydrogen peroxide. In addition, the catalytic ramsdellite MnO2(R-MnO2) inner layer is decorated with Fe2O3 nanoparticles to improve their catalytic performance, contributing to an excellent degradation ability with 90% tetracycline (TC) removal in 50 minutes by enhanced Fenton-like reactions. Combining the attractive adsorption capability of poly (aspartic acid) (PASP), the composite micromotors offer an efficient removal of heavy metal ions in short time. Moreover, the designed micromotors are able to simultaneously remove antibiotic and heavy metals in mixed contaminants circumstance just in single treatment. This multifunctional micromotor with distinctive decontamination ability exhibits a promising prospective in treating multiple pollutants in the future.  相似文献   
2.
It is explicitly shown that if phase transition occurs at the core of a newborn neutron star with moderately strong magnetic field strength, which populates only the electron’s Landau levels, then in the β -equilibrium condition, the quark core is energetically much more unstable than the neutron matter of identical physical condition.  相似文献   
3.
For more than 25 years production has helped to sharpen our understanding of QCD. In proton induced reaction some observations are rather well understood while others are still unclear. The current status of the theory of production will be sketched, paying special attention to the issues of formation time and re-interaction in a nuclear medium.  相似文献   
4.
Based on Dyson Schwinger Equations (DSEs) in the “rainbow” approximation, the dependence of quark effective mass on gluon propagator is investigated by use of three different phenomenological gluon propagators with two parameters, the strength parameter x and range parameter △. Our theoretical calculations for the quark effective mass Mf(p^2), defined by the self-energy functions Af(p^2) and Bi(p%2) of the DSEs, show that the dynamically running quark effective mass is strongly dependent on gluon propagator. Therefore, because gluon propagator is completely unknown, the quark effective mass cannot be exactly determined theoretically.  相似文献   
5.
The characteristic exponent α of a Lévy-stable law S α (σ, β, μ) was thoroughly studied as the extreme value index of a heavy tailed distribution. For 1 < α < 2, Peng (Statist. Probab. Lett. 52: 255–264, 2001) has proposed, via the extreme value approach, an asymptotically normal estimator for the location parameter μ. In this paper, we derive by the same approach, an estimator for the scale parameter σ and we discuss its limiting behavior.   相似文献   
6.
Calculations of helicity amplitudes for the low-lying nucleon resonances are displayed based on a non-relativistic constituent quark model with a harmonic oscillator confinement. The explicit effect of quark confinement isshown. Our results show that the effect plays sizable role on some transition amplitudes of S11(1535) and D13(1520)resonances. The effect on the △(1232) transition amplitudes islessthan 10%. However, the effect on the Roper resonanceis remarkable but is inconclusive.  相似文献   
7.
We present some of our results for the electromagnetic properties of excited Σ hyperons, computed within the framework of the Bonn constituent-quark model, which is based on the Bethe-Salpeter approach. The seven parameters entering the model are fitted against the best-known baryon masses. Accordingly, the results for the form factors and helicity amplitudes are genuine predictions. We compare with the scarce experimental data available and discuss the processes in which Σ *'s may play an important role.  相似文献   
8.
Four NiMo catalyst supported on Al2O3 with different textural properties have been studied in the hydrodesulfurization (HDS), hydrodenitrogenation (HDN) and hydrodearomatization (HDA) of a Mexican straight run gasoil (SRGO). All reactions were carried out at three different temperatures 613, 633, and 653 K. Alumina supports were analysed by pyridine FTIR-TPD and nitrogen physisorption in order to determine their surface acidity and textural properties, respectively. TPR studies of the NiMo catalysts were analysed to correlate their hydrogenating properties. Metallic particles were characterized (after sulfidation) using transmission electron microscopy (TEM). Catalytic activities are discussed in relation to the physicochemical properties of NiMo catalysts. The importance of textural properties on coke deposition has been emphasized. The results of catalytic activity of these materials varied depending on dispersed MoS particles and pore distribution in final catalysts. The optimum pore diameter was found around 80 Å for HDS and HDN.  相似文献   
9.
合成了重稀土高氯酸盐甲基苯甲酰甲基亚砜配合物RE(ClO4)3·L5·C2H5OH(RE=Gd,Tb,Dy,Tm,Yb;L=C6H5COCH2SOCH3).经元素分析、稀土络合滴定、摩尔电导及热重分析确定了配合物的组成,测定了配体及配合物的IR谱、1H NMR及铽配合物的磷光光谱、荧光激发和发射光谱,根据荧光发射光谱数据计算了铽配合物的各能级值.  相似文献   
10.
利用一个描述强子质量谱成功的夸克模型确定出得到的强子多重数普适质量关系〈n〉=aexp(–bm)中的参数b,发现对于介子、重子是一个普适的常数.利用这个质量公式给出计算各种粒子多重数的表达式,进而以高能e+e湮没为例计算出各种粒子多重数与实验以及其他模型做了比较,表明这个没有任何假定的质量关系同样能够解释实验.  相似文献   
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