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Many important chemical kinetic systems require detailed chemical kinetic models to resolve. These detailed kinetic models can involve thousands of species and hundreds of thousands of chemical reactions, making them difficult to construct by hand. Modern automatic mechanism generation algorithms can mostly be divided into two classes: rule and rate based. Rule‐based generators choose species based on user defined constraints on species and reaction classes. Rate‐based generators generate a much larger set of potentially important species and reactions and then choose which ones to add based on running simulations of species and reactions deemed important and calculating the flux to potentially important species. In principle, the latter is preferable, as it requires the user to make far fewer assumptions about what is important in the system. However, while the effectiveness of the rate‐based approach has been demonstrated in a wide variety of systems, it has also been demonstrated to have difficulty picking up important low‐flux chemistries. Here we present a discussion of the challenges associated with rate‐based mechanism generation and new algorithms that are able to efficiently mitigate these challenges improving species selection during mechanism generation in a set of case studies. [ABSTRACT FROM AUTHOR]

We present ReactionMechanismSimulator.jl (RMS), a modern differentiable software for the simulation and analysis of chemical kinetic mechanisms, including multiphase systems. RMS has already been applied to problems in combustion, pyrolysis, polymers, pharmaceuticals, catalysis, and electrocatalysis. RMS is written in Julia, making it easy to develop and allowing it to take advantage of Julia's extensive numerical computing ecosystem. In addition to its extensive library of optimized analytic Jacobians, RMS can generate and use Jacobians computed using automatic differentiation and symbolically generated analytic Jacobians. RMS is demonstrated to be faster than Cantera and Chemkin in several benchmarks. RMS also implements an extensive set of features for analyzing chemical mechanisms, including a library of easy‐to‐call plotting functions, molecular structure resolved flux diagram generation, crash analysis, traditional sensitivity analysis, transitory sensitivity analysis, and an automatic mechanism analysis toolkit. RMS implements efficient adjoint and parallel forward sensitivity analyses. We also demonstrate the ease of adding new features to RMS. [ABSTRACT FROM AUTHOR]

A titanium oxide-selenide (TiO1.1Se0.9) composite material was successfully obtained on a flexible substrate of carbon cloth (CC); this TiO1.1Se0.9/CC electrode was used as the counter electrode (CE) in a dye-sensitized solar cell (DSSC). Each carbon fiber in the CC was wrapped with a composite layer of TiO1.1Se0.9, and the composite layer contained TiO1.1Se0.9 nanospheres and one-dimensional (1D) nanorods. Thus, each carbon fiber with its TiO1.1Se0.9 layer has a hierarchical core–shell structure, in which the carbon fiber acts as a one-dimensional conductive core for electron transfer and the TiO1.1Se0.9 layer around the fiber functions as an electro-catalytic shell. In iodide-based electrolyte, the DSSC with the TiO1.1Se0.9/CC exhibits a power conversion efficiency (η) of 9.47%, which is higher than cells with CEs of Pt/CC (7.75%) and pristine TiO2/CC (4.90%). Under dim light conditions, the best TiO1.1Se0.9/CC electrode rendered its cell an η of 10.00% at 0.5 sun and the best η of 10.39% at 0.1 sun. In cobalt-based electrolytes, a DSSC with the TiO1.1Se0.9/CC shows an attractive η of 10.32% at 1.0 sun, the best η of 10.47% at 0.5 sun, and an impressive η of 10.20% at 0.1 sun. The earth abundant and low-cost TiO1.1Se0.9 is a promising alternative to Pt for the CE of a DSSC in both iodide and cobalt electrolytes. [ABSTRACT FROM AUTHOR]

Aim: To compare the staging systems for stratifying and predicting the prognosis of patients with hepatocellular carcinoma (HCC) after partial hepatectomy (PH)., Methods: Clinical data about 438 HCC patients who underwent PH from January 1991 to December 2004 at our hospital were retrospectively analyzed. Tumor stage was evaluated following the Chinese tumor node metastasis (TNM) and barcelona clinic liver cancer (BCLC) staging systems, respectively. Survival curves for the HCC patients were plotted using the Kaplan-Meier method and differences were compared by the log-rank test. The accuracy of each system for predicting death of HCC patients was evaluated by calculating the area under the receiver operating characteristic curve., Results: The HCC patients were classified into stages I-III, stages I-IV and stages A-C, according to the 3 staging systems, respectively. Log-rank test showed that the cumulative survival rate was significantly different for the HCC patients at 3 Chinese system stages, TNM stages I and II, TNM stages III and IV, and 3 BCLC stages (P < 0.05). However, no significant difference was found in the HCC patients at TNM stages II and III. The accuracy of the Chinese and BCLC staging systems was higher than that of the TNM staging system for predicting the survival rate of HCC patients., Conclusion: The Chinese and BCLC staging systems are better for stratifying and predicting the prognosis of HCC patients after PH than the TNM staging system.