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基于非凸变分方法在图像边界结构保持和对比度保持上的优势，针对泊松噪声的移除问题提出一种新的非凸非光滑正则化模型及快速求解算法。模型由非凸Lipschitz势函数复合图像梯度信息的正则化项和非线性Kullback-Leibler数据保真项两部分构成。通过使用临近点线性化策略，将求解非凸变分模型转化为求解一系列凸变分模型，进而使用交替方向乘子法求解。同时证明了算法的目标函数值序列具有单调下降性。实验结果表明，该方法能有效消除图像中的泊松噪声，且信噪比较经典算法有明显提升。

In view of the lack of skid resistance of asphalt pavement of some highways, the representative section of a road were selected, combined with the analysis results of basic data and road condition data, field tests and laboratory tests were carried out to analyze the reasons for the decline of skid resistance. The attenuation law of asphalt pavement performance with traffic load was simulated by using the detection method at different positions of the road. According to the attenuation characteristics of different indexes, the evaluation methods of asphalt pavement skid resistance performance are refined. Based on the conclusions of special testing and analysis, the skid resistance performance evaluation model, road condition decay model and maintenance decision model were developed to carry out long-term maintenance planning for the road, keep the annual maintenance mileage stable during the planning period, and avoid the maintenance pressure concentrating on a few years. Combined with the current situation of road condition and attenuation law, the road condition in the planning period is predicted to prove the results of long-term maintenance planning under the decision model, which ensures the stability of the road condition level in the planning period.

Supersulfated cements (SSCs), as potential green alternatives to Portland cements, are in demand for developing new kinds of precursors instead of blast-furnace slag. A mixture of kaolin, quartz and sodium hydroxide was calcined to prepare SSC by grinding clinkers with lime and gypsum. Preparation factors were investigated and multiple characterisation methods were adopted to explore the calcination and hydration mechanisms. The sodium hydroxide additive was found to reduce the activation temperature of the kaolin and a moderate addition of sodium hydroxide improved the compressive strength of SSC made from calcined kaolin. Quartz added into the kaolin calcined with a moderate amount of sodium hydroxide also promoted the compressive strength. Comprehensive characterisations indicated that the alkali-added calcination of the kaolin generated pozzolanic zeolite and sodium aluminosilicates along with inert nepheline at a calcination temperature ≤950°C. The hydration of SSC pastes tended to produce C(N)–A–S–H/N(C)–A–S–H gels and crystalline ettringite. During sodium hydroxide-added calcination, quartz added into the kaolin hindered the generation of inert nepheline and produced cementitious N–S gels. The research facilitates the utilisation of the massive discharged coal gangues rich in kaolinite and quartz by synthesising SSCs economically. [ABSTRACT FROM AUTHOR]

Lewisite is a representative chemical warfare agent that contains arsenic. Thermal decomposition is an essential method for Lewisite destruction, and appropriate destruction conditions can enhance the environmental friendliness of this method by minimizing the hazards of destruction products. In this study, the variation of Lewisite during pyrolysis and incineration was calculated, with particular emphasis on the evolution behaviors of arsenic and chloride with temperature, pressure, and molar ratio. The main products identified during pyrolysis were HCl(g), C, As, and AsCl3(g). Under anoxic conditions, AsCl3(g) and As were the dominant species. In oxygen‐enriched conditions, arsenic existed primarily as AsCl3(g), As2O5, As2O4, and AsOCl. Below 600 °C, arsenic predominantly existed in high valence forms such as As2O5. Above 600 °C, the binding capacity of chlorine and arsenic was stronger than that of oxygen, resulting in an AsCl3(g) molar fraction exceeding 75 % at 1200 °C. The primary chlorides in oxygen‐enriched conditions were Cl2(g), HCl(g), AsCl3(g), and Cl(g). Lower incineration temperatures (around 500 °C), sufficient oxygen conditions (molar ratio above 4 : 1), and positive pressures were conducive to reducing the toxicity of destruction products. The results are in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

This study considers critical data reduction steps and data analysis approaches required to determine explicitly the atomic arrangements in nanoparticles from time‐of‐flight neutron total scattering. A practical procedure is described for removing parasitic backgrounds caused by the incoherent scattering of hydrogen inevitably present in most nanoparticle samples and normalizing the recovered coherent scattering intensities onto an absolute scale. A model‐free analysis is presented of a pair‐distribution function derived from total scattering that can be used to determine thermal expansion coefficients and particle sizes directly from experimental data without knowledge of the material's structure. Finally, atomistic whole‐nanoparticle refinements of yttrium‐doped ceria nanoparticles from neutron total‐scattering data are demonstrated using the reverse Monte Carlo method implemented in the RMCProfile software. These results reveal a strong dependence of the cation–oxygen and oxygen–oxygen distances on the coordination numbers, which leads to gradients of these distances near the particle surface. The details are dependent on the surface coverage by ligands and adsorbates and on the structure of grain boundaries in nanocrystalline agglomerates. The refined models confirm the expectations of more substantial disorder at particle surfaces, with a distorted surface layer extending over several coordination shells. The results highlight the feasibility of whole‐nanoparticle refinements from neutron data, calling for further development of data reduction and analysis procedures. [ABSTRACT FROM AUTHOR]

This work introduces a completely rewritten version of the program RMCProfile (version 7), big‐box, reverse Monte Carlo modelling software for analysis of total scattering data. The major new feature of RMCProfile7 is the ability to refine multiple phases simultaneously, which is relevant for many current research areas such as energy materials, catalysis and engineering. Other new features include improved support for molecular potentials and rigid‐body refinements, as well as multiple different data sets. An empirical resolution correction and calculation of the pair distribution function as a back‐Fourier transform are now also available. RMCProfile7 is freely available for download at https://rmcprofile.ornl.gov/. [ABSTRACT FROM AUTHOR]