Organization and energy properties of metastable states for the random-field Ising model

Random-field Ising model (RFIM) systems are characterized by a large number of metastable states corresponding to local minima of the system energy with respect to single spin flip. We classified the minima in a hierarchical way based on the possibility of a given state to escape from a basin of mutually reachable states. We investigate the energy properties of the metastable states in relation to the basin they belong to: states of particularly high energy, obtained by fast-quenching randomly initial spin configurations, tend to have access to a complex structure of correlated basins, opposite to what is found for low-energy states. The purpose of this paper is to investigate the connection between the properties of the basin oriented graph and the energy of the corresponding states.     

Large-strain numerical solution for coupled self-weight consolidation and contaminant transport considering nonlinear compressibility and permeability

Based on the one-dimensional (1D) consolidation equation and advection-dispersion transport equation, this paper presents a large-strain numerical solution for coupled self-weight consolidation and contaminant transport in saturated deforming porous media considering nonlinear compressibility and permeability relationships. The finite difference method is used to solve the governing equations for consolidation and transport. The proposed numerical solution for consolidation accounts for vertical strain, soil self-weight, and nonlinearly changing compressibility and hydraulic conductivity during consolidation. The solution for solute transport accounts for advection, diffusion, mechanical dispersion, linear and nonlinear equilibrium sorption, and porosity-dependent effective diffusion coefficient. The proposed numerical solution is verified against a self-weight consolidation field tank test, an analytical solution in the literature, and the CST1 numerical model. Using the verified solution, a series of parametric study is conducted to investigate the effect of several important parameters on the contaminant transport process for confined disposal of dredged contaminated sediments. The results indicate that the consolidation process and contaminant transport process induced by soil self-weight- can be very different from those induced by the more traditional external surcharge loading. Treating the self-weight loading as traditional external surcharge loading can underestimate the rate of contaminant outflow, especially in the early times. The compressibility and permeability relationships of sediment and the type of loading (i.e., self-weight loading versus external surcharge loading) can all significantly affect the contaminant transport process for confined disposal of dredged contaminated sediment.     

高温水热合成具有高稳定性的有序介孔材料

高温水热合成路线作为合成具有超高稳定性的介孔材料越来越受到人们的重视.本文对高温水热合成有序介孔材料的发展过程作一个简单的综述,合成路线包括使用碳氟表面活性剂和碳氢表面活性剂作为复合模板,有机季铵盐与碳氢表面活性剂作为复合模板以及最近报道的采用碳氢表面活性剂作为单一模板来合成系列的有序介孔材料,其组成为二氧化硅、氧化钛硅以及聚合物等.     

局域空间噪声主动控制技术的进展

低频噪声主动控制技术实现实用化，需要同时了解其在声学和电子控制方法上的可实现性，本文在系统的文献检索的基础上，综述了局域空间自适应噪声主动控制技术的发展，内容包括用次级声源控制室外局域噪声，围护结构内的局域空间和室外向室内传播的小范围区域空间噪声主动控制在声学上的限制（原理），以及各种控制策略和算法的应用，本文列出的文献包括了已有的重要研究成果，可为读者进一步了解该领域的研究提供详细的背景材料。     

气相色谱法分离和测定环境空气中的丙烯酸乙酯和甲基丙烯酸甲酯

用活性炭吸附环境空气中的丙烯酸乙酯和甲基丙烯酸甲酯,经二硫化碳妥吸后用气相色谱法测定在填充２．５％ＤＮＰ＋２．５％Ｂｅｎｔｏｎｅ３４／ＣｈｒｏｍｏｓｏｒｂＷ ＨＰ ＤＭＣＳ的玻璃色谱柱上,丙烯酸乙酯与甲基丙烯酸甲酯及干扰物之间能较好地分离。方法的回收率：丙烯酸乙酯为８６．４％－１０３．０％,甲基丙烯酸甲酯为８６．３％－１０１．２％,变异系数：丙烯酸乙酯为４．１％－４．４％,甲基丙烯酸甲酯为４．４％     

A spectroscopic study on the interaction between the anticancer drug erlotinib and human serum albumin

The interaction between erlotinib and human serum albumin (HSA) in simulated physiological conditions was investigated by spectroscopic methods. The results revealed that erlotinib caused the fluorescence quenching of HSA through a static quenching procedure. The binding constants at 293, 298, 303 and 308 K were obtained as 2.53 × 10⁵, 8.13 × 10⁴, 3.59 × 10⁴ and 1.93 × 10⁴ M^?1, respectively. There may be one binding site of erlotinib on HSA at 298 K. The thermodynamic parameters indicated that the interaction between erlotinib and HSA was driven mainly by hydrogen bonding or van der Waals forces. Synchronous fluorescence spectra, UV–Vis spectra, circular dichroism and Fourier Transform infrared spectroscopy results showed erlotinib binding slightly changed the conformation of HSA with secondary structural content changes. Förster resonance energy transfer study revealed high possibility of energy transfer with erlotinib-Trp-214 distance of 3.48 nm. The results of the present study may provide valuable information for studying the distribution, toxicological and pharmacological mechanisms of erlotinib in vivo.     

原子荧光法测定植物样品中的硒

研究建立了氢化物发生-原子荧光光谱法测定植物样品中硒的方法,对样品处理、干扰及消除进行了探讨。结果表明,该法的检出限为0.56ng/g,回收率为93.6%~99.2%,RSD为2.8%~5.2%。     

Synergistic effect of Fe2O3/Ho2O3 Co-modified 2D-titanate heterojunctions on enhanced photocatalytic degradation

TiO₂-based nanosheets (TNSs) co-modified by Fe₂O₃ and Ho₂O₃ were synthesized by one-pot hydrothermal method using Fe(NO₃)₃ and Ho(NO₃)₃ as precursors compositing with TiO₂. The Fe₂O₃/Ho₂O₃-TNSs heterojunctions possessed a thickness of approximately 3–4 nm, large specific surface area of 210–310 cm²/g, with Fe₂O₃ and Ho₂O₃ nanoparticles highly dispersed over the surface of the nanosheets. The crystallization of the samples gradually increased with the amount of Fe₂O₃ nanoparticles, which was confirmed by the XRD, BET and Raman spectra, indicating that Ho₂O₃ and Fe₂O₃ influenced the crystallinity and structure evolution of the TNSs, besides, led to an improved the visible-light absorption. Surface photocurrent and fluorescence spectral studies revealed that the photo-generated charge carrier separation efficiency could be efficiently improved by an appropriate amount of modification. The Fe₂O₃/Ho₂O₃-TNSs exhibited synergistic effect on photocatalytic degradation of RhB as well as MO under visible light. The highest efficiency was obtained by 0.05%-Fe₂O₃/Ho₂O₃-TNSs (Fe:Ho:Ti = 0.05:1:100), which was 8.86 and 6.72 times than that of individual 1.0%-Ho₂O₃-TNSs (Ho:Ti = 1:100) and 0.05%-Fe₂O₃-TNSs (Fe:Ti = 0.05:100), respectively. The possible mechanism for enhanced visible-light-induced photocatalytic activity was proposed. Ho₂O₃ introduced in the photocatalysts may act as the hole capture while Fe₂O₃ may share the same Fermi levels with TNSs and serve as the electron capture center in the n-n-p system, which reduced the recombination rate of photo-induced electron-hole pairs.     

Unveiling the secondary pollution in the catalytic elimination of chlorinated organics: The formation of dioxins

Since the discovery of polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs) in the process of municipal solid waste incineration(MSWI),a large number of researches have been conducted to reveal their formation mechanisms and emission characteristics.As one of national priority control pollutants,chlorinated organics are inclined to transfer into PCDD/Fs in the heterogeneously catalyzed process,which has been considered to be one of great challenges in environmental catalysis.However,so far direct evidences to support such a conversion process are insufficient,and the reaction mechanisms are lack of exploration.This study investigated the catalytic elimination of chlorobenzene(CBz) over a range of industrially applied active species including Pt,Ru,V,Ce and Mn oxides,and explored their reaction byproducts,chlorine adsorption/desorption behaviors and PCDD/F formations.We found that all of these species could generate the PCDD/Fs,amongst which,Mn species were the most active for PCDD/F formation.Approximately 140 ng I-TEQg-1 PCDD/Fs were detected on the Mn-CNT surface after ageing at250℃ for 30 h.Even using the dichloromethane(DCM) as a precursor,significant PCDD/Fs were still detected.The Ru and V species were shown to generate much less polychlorinated byproducts and PCDD/Fs,owning to their sufficiently high abilities in Cl desorption,which were through the semi-Deacon and Br(?)nsted H reactions,respectively.