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Microwave Assisted Ignition (MAI) is a promising technology to optimize the lean combustion characteristics of internal combustion engines. This research investigated the effects of microwave pulse waveform and delay time on energy coupling and ignition enhancement by using a power diagnostic with high time-resolution. The pulse width ranged from 80 to 200 μs and the corresponding peak power was adjusted between 1000 and 400 W to keep the incident energy of microwave pulse constant. Results showed that a high power and short width pulse waveform was conducive to the microwave energy absorption. The coupled energy generally decreased with delay time. There was a significant ignition enhancement with only 6∼7 mJ energy coupled into the flame kernel, which was approximately 1/5 of total spark energy. Moreover, the ignition enhancement was well correlated with the coupled energy, suggesting that ignition enhancement was determined by coupled energy via electron collision reactions. Finally, the main influencing factor of coupled energy was the energy coupling pattern which changed from none-coupling to saturated coupling. A high pulse power and short delay time facilitated this change. This study revealed the saturated coupling pattern independent of waveform and delay time, which is caused by a stable electron number density due to the cut-off effect. [ABSTRACT FROM AUTHOR]

The direct growth of graphene at low temperatures on the desired dielectric substrate by plasma-enhanced chemical vapor deposition (PECVD) is significant for its electronic and optoelectronic applications. However, due to the high nucleation density, low-quality nanographene with small domain size is always grown, leading to a decline in their electrical performance. In this work, by effectively reducing the total nucleation density, high-quality large graphene crystals with hexagonal shape, 0.5 μm size and uniform thickness were grown on the SiO2/Si substrate. The higher intensity ratio of Raman 2D peak to G peak (I2D/IG ∼ 1.58) and the smaller intensity ratio of D peak to G peak (ID/IG ∼ 1.15) for these crystals verify their much better quality than that of nanographene with an I2D/IG value of ∼0.35 and an ID/IG value of ∼1.57. In particular, the initial nucleation density in a given short growth time was first controlled to be low, less than 5 μm−2, and the subsequent multiple nucleation in the following long-time growth was suppressed under the optimized growth condition such as plasma power and growth temperature. This ensures a low total nucleation density all the time during growth, and thus facilitates the successful growth of large graphene crystals. This work will promote the study of low-temperature growth techniques of graphene on dielectric substrates, as well as the large-scale applications of graphene. [ABSTRACT FROM AUTHOR]

To improve prognosis of cancer patients and determine the integrative value for analysis of disease-free survival prediction, a clinic investigation was performed involving with 146 non-small cell lung cancer (NSCLC) patients (83 men and 73 women; mean age: 60.24 years ± 8.637) with a history of surgery. Their computed tomography (CT) radiomics, clinical records, and tumor immune features were firstly obtained and analyzed in this study. Histology and immunohistochemistry were also performed to establish a multimodal nomogram through the fitting model and cross-validation. Finally, Z test and decision curve analysis (DCA) were performed to evaluate and compare the accuracy and difference of each model. In all, seven radiomics features were selected to construct the radiomics score model. The clinicopathological and immunological factors model, including T stage, N stage, microvascular invasion, smoking quantity, family history of cancer, and immunophenotyping. The C-index of the comprehensive nomogram model on the training set and test set was 0.8766 and 0.8426 respectively, which was better than that of the clinicopathological-radiomics model (Z test, P =0.041<0.05), radiomics model and clinicopathological model (Z test, P =0.013<0.05 and P =0.0097<0.05). Integrative nomogram based on computed tomography radiomics, clinical and immunophenotyping can be served as effective imaging biomarker to predict DFS of hepatocellular carcinoma after surgical resection. [ABSTRACT FROM AUTHOR]

Due to high power-transforming capability and excellent fault-tolerant performance, dual three-phase permanent magnet synchronous machines (DT-PMSMs) are widely used in high-reliability applications. Concerning on the remedial strategy for DT-PMSMs under open-phase faults, the conventional method is to reconfigure the controller or the current references in order to obtain optimum postfault performances. Two different control schemes should be separately designed for normal and fault conditions, respectively. Meanwhile, related fault detection measures need to be adopted and the inherent fault detection delay will further result in transient performance deterioration. In order to solve these problems, this article proposes a control strategy, which can achieve natural fault-tolerant capability of DT-PMSMs without additional fault detection algorithm. With the proposed control method adopted, reconfiguration of the control structure and modification of the current command are not required. Thus, the control scheme is simplified. The transition from the healthy to the postfault operation can be improved, meanwhile, the steady-state performances in prefault and postfault situations can be guaranteed. The proposed strategy can be generally applied to single open-phase faults and multiple open-phase faults in DT-PMSMs. Experimental validations are presented on a 1 kW DT-PMSM platform to prove the effectiveness of the proposed strategy. [ABSTRACT FROM AUTHOR]

In the ca. 1.0 Ga paleogeographic reconstruction, the North China Craton (NCC) is placed near Siberia, Laurentia, the Northern Australia Craton (NAUS), Baltica or India. To distinguish among these possibilities, we present inverse Monte Carlo modelling of the Xihe Group from the eastern NCC (ENCC), which is dominated by Grenvillian orogeny‐related detrital zircon age peaks, and of potential provenances (including NAUS, Siberia, Laurentia, India and the North Atlantic region). The result reveals that the ENCC–NAUS connection model yields the best mean cross‐correlation coefficient (R2 = ~0.92), which is also supported by the similarity in median εHf values between the Qiaotou Formation (Xihe Group) and the Jamison sandstones from the NAUS. The NCC–NAUS connection possibly records the breakup of Nuna and the assembly of Rodinia. [ABSTRACT FROM AUTHOR]