This contribution is focused on the fuel economy improvement of the Miller cycle under part-load characteristics on a supercharged DI (Direct Injection) gasoline engine. Firstly, based on the engine bench test, the effects with the Miller cycle application under 3000 rpm were studied. The results show that the Miller cycle has different extents of improvement on pumping loss, combustion and friction loss. For low, medium and high loads, the brake thermal efficiency of the baseline engine is increased by 2.8%, 2.5% and 2.6%, respectively. Besides, the baseline variable valve timing (VVT) is optimized by the test. Subsequently, the 1D CFD (Computational Fluid Dynamics) model of the Miller cycle engine after the test optimization at the working condition of 3000 rpm and BMEP (Brake Mean Effective Pressure) = 10 bar was established, and the influence of the combined change of intake and exhaust valve timing on Miller cycle was studied by simulation. The results show that as the effect of the Miller cycle deepens, the engine’s knocking tendency decreases, so the ignition timing can be further advanced, and the economy of the engine can be improved. Compared with the brake thermal efficiency of the baseline engine, the final result after simulation optimization is increased from 34.6% to 35.6%, which is an improvement of 2.9%.

A major feature of cancer is the heterogeneity, both intratumoral and intertumoral. Traditional single-cell techniques have given us a comprehensive understanding of the biological characteristics of individual tumor cells, but the lack of spatial context of the transcriptome has limited the study of cell-to-cell interaction patterns and hindered further exploration of tumor heterogeneity. In recent years, the advent of spatially resolved transcriptomics (SRT) technology has made possible the multidimensional analysis of the tumor microenvironment in the context of intact tissues. Different SRT methods are applicable to different working ranges due to different working principles. In this paper, we review the advantages and disadvantages of various current SRT methods and the overall idea of applying these techniques to oncology studies, hoping to help researchers find breakthroughs. Finally, we discussed the future direction of SRT technology, and deeper investigation into the complex mechanisms of tumor development from different perspectives through multi-omics fusion, paving the way for precisely targeted tumor therapy.

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Based on the first successful application of new prefabricated technology in underground metro stations on line 2 of the Changchun Metro in China, a comprehensive analysis and discussion on research strategies for new prefabricated technology for large underground structures is provided. This paper introduces the application status of prefabricated technology in underground engineering worldwide, illustrates the different characteristics of prefabricated technology applied to ground buildings and underground structures, puts forward the key technologies, and compares the major technical, economic, and social benefits achieved. The successful application of prefabricated technology for underground structures in Changchun Metro demonstrates the feasibility and great advantages of the new prefabricated technology for underground engineering. Keywords Metro station Á Prefabricated technology Á Monolithic precast concrete structure Á Superimposed prefabricated integral structure Á Fully prefabricated structure Á Rebar splicing by grout-filled coupling sleeve Á Grouted mortise-tenon joint Á Closed-cavity thin-walled components & Xiuren Yang

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A Portable Emission Measurement System was used in this study to evaluate the exhaust emission characteristics of nitrogen oxides (NOx), ultrafine particulate matter (PM), and ultrafine particulate number (PN) from buses in the Yangtze River Delta, China. Results showed that NOx emission factor (unit: g•km −1) increased from 5.0 to 19.1, and PM emission factor (unit: g•km −1) increased from 0.001 to 0.189. A nonlinear model was established based on scientific statistical method, which showed that NOx and PM emission factors significantly decreased with speed increasing. The model also showed a "long tail effect" of NOx and PM emission factors beyond 30 km•h −1. Furthermore, hybrid bus exhausted less NOx, PM, and PN emissions compared to conventional bus in the acceleration condition. Exhaust rates of NOx, PM and PN emissions (unit: g•s −1) increased with speed increasing under steady state driving condition, while PN emissions commonly showed a unimodal distribution at the speed of 20 km•h −1 .