70 research outputs found
Synthesis of ultra-narrow PbTe nanorods with extremely strong quantum confinement
Monodisperse, high-quality, ultra-narrow PbTe nanorods were synthesized for the first time in a one-pot, hot-injection reaction using trans-2-decenoic acid as the agents for lead precursors and tris(diethylamino)phosphine telluride together with free tris(diethylamino)phosphine as the telluride precursors. High monomer reactivity, rapid nucleation and fast growth rate derived from the new precursors led to the anisotropic growth of PbTe nanocrystals at low reaction temperatures
High expression of nucleophosmin is closely related to the grade and invasion of colorectal cancer
420-426This study explores the differential protein expression in the colorectal cancer (CRC) patients to validate a new biomarker for tumor progression. CRC tissues and their adjacent non-cancerous tissues were analyzed by two-dimensional LC/MS/MS. Nucleophosmin 1 (NPM1) was selected and confirmed its differential expression by Western blot. Immunohistological staining of NPM1 in tissues was performed to validate its correlation with clinicopathologic parameters of CRC patients. There were 39 candidates with significant difference between cancerous tissues and their adjacent
non-cancerous tissues, which included 19 increased proteins and 20 decreased proteins in CRC samples. Especially, NPM1 was correlated with poor differentiation, and lymph node metastasis according to the analysis of patients’ clinicopathologic parameters. Increased expression of NPM1 can be as a critical biomarker for clinical diagnosis of tumor progression of CRC patients
High expression of nucleophosmin is closely related to the grade and invasion of colorectal cancer
To explore the differential protein expression in the colorectal cancer (CRC) patients to validate a new biomarker for tumor progression. CRC tissues and their adjacent non-cancerous tissues were analyzed by two-dimensional LC/MS/MS. Nucleophosmin 1 (NPM1) was selected and confirmed its differential expression by Western blot. Immunohistological staining of NPM1 in tissues was performed to validate its correlation with clinicopathologic parameters of CRC patients. There were 39 candidates with significant difference between cancerous tissues and their adjacent non-cancerous tissues, which included 19 increased proteins and 20 decreased proteins in CRC samples. Especially, NPM1 was correlated with poor differentiation, and lymph node metastasis according to the analysis of patients’ clinicopathologic parameters. Increased expression of NPM1 can be as a critical biomarker for clinical diagnosis of tumor progression of CRC patients
The Temporal Evolution of Coastlines in the Bohai Sea and Its Impact on Hydrodynamics
Over the past 40 years, increasing coastal reclamation and natural sedimentation has changed coastline positions and resulted in variation in the hydrodynamic environment in the Bohai Sea (BHS), China. Based on the Landsat series images, an interpretative identifier for identifying the coastline was proposed to assess the hydrodynamic changes caused by the coastline change and was applied to a typical case of the Bohai Sea (BHS), China. We combined a grid-based coastline position with an adjoint data assimilation method to seamlessly map the distribution of the amplitude, phase lag, and tidal current of the M2 tidal constituent along the BHS’s coast from 1985 to 2018. Our findings reveal that the coastline change at long time scales dominated reclamation, and around 72.9% of the coastline of the BHS mapped in 2018 had seaward movement compared with its position in 1985. From 1985 to 2018, the BHS volume decreased by 0.17%, the sea surface area decreased by 4.54%, and the kinetic energy increased by 2.53%. The change in the coastline increased the amplitude of the M2 tidal constituent in the Bohai Bay by 6–14 cm and increased the residual current in the eastern coast of the Liaodong Bay by up to 0.07 (0.01) m/s
Multi-Physics Multi-Objective Optimal Design of Bearingless Switched Reluctance Motor Based on Finite-Element Method
The bearingless switched reluctance motor (BSRM) integrates the switched reluctance motor (SRM) with the magnetic bearings, which avoids mechanical bearings-loss and makes it promising in high-speed applications. In this paper, a comprehensive framework for the multi-physics multi-objective optimal design of BSRMs based on finite-element method (FEM) is proposed. At first, the 2-D electromagnetic model of a fabricated initial design prototype is built and solved by the open-source FEM software, Elmer. The iron loss model in Elmer based on the Fourier series is modified by a transient iron loss model with less computation time. Besides, a simplified lumped-parameter (LP) thermal model of the BSRM is applied to estimate the temperature rise of BSRM in the steady state. Then, the comprehensive framework for the multi-physics multi-objective optimal design of BSRMs based on FEM is proposed. The objectives, constraints, and decision variables for optimization are determined. The multi-objective genetic particle swarm optimizer is utilized to obtain the Pareto front of optimization. The electromagnetic performance of the final optimal design is compared with the initial design. Comparison results show that the average electromagnetic torque and the efficiency are significantly enhanced
The Temporal Evolution of Coastlines in the Bohai Sea and Its Impact on Hydrodynamics
Over the past 40 years, increasing coastal reclamation and natural sedimentation has changed coastline positions and resulted in variation in the hydrodynamic environment in the Bohai Sea (BHS), China. Based on the Landsat series images, an interpretative identifier for identifying the coastline was proposed to assess the hydrodynamic changes caused by the coastline change and was applied to a typical case of the Bohai Sea (BHS), China. We combined a grid-based coastline position with an adjoint data assimilation method to seamlessly map the distribution of the amplitude, phase lag, and tidal current of the M2 tidal constituent along the BHS’s coast from 1985 to 2018. Our findings reveal that the coastline change at long time scales dominated reclamation, and around 72.9% of the coastline of the BHS mapped in 2018 had seaward movement compared with its position in 1985. From 1985 to 2018, the BHS volume decreased by 0.17%, the sea surface area decreased by 4.54%, and the kinetic energy increased by 2.53%. The change in the coastline increased the amplitude of the M2 tidal constituent in the Bohai Bay by 6–14 cm and increased the residual current in the eastern coast of the Liaodong Bay by up to 0.07 (0.01) m/s
Reactive Power Output Modeling of Synchronous Condenser in UHVDC Converter Station Based on Interlaced Superposition CNN-BiLSTM
Abstract To guarantee stable power system operation, a synchronous condenser (SC) is configured in an ultra-high voltage direct current (UHVDC) converter station to provide dynamic reactive power support to the power system. The research on the reactive power output modelling of a SC in an UHVDC converter station has important theoretical significance and practical value for the reactive power control of a SC in an UHVDC converter station. Focusing on the reactive power regulation system of the SC with strong coupling, multivariable, and nonlinear features, it is difficult for the universal analytic method to build the SC reactive power output model. A novel reactive power output model of the SC in the UHVDC converter station based on interlaced superposition convolutional neural network-bidirectional long short-term memory (CNN-BiLSTM) is proposed, in which a novel interlaced superposition CNN composed of convolution units with two different structures is built to increase the depth of the network and avoid over-fitting. Particularly the branch channels of convolution units with two different structures are connected by a convolution layer and a skip connection respectively. The interlaced superposition CNN-BiLSTM model is that the combination of the interlaced superposition CNN model and BiLSTM model for improving the model accuracy and generic capability. The Bayesian optimization method is used to optimize its hyperparameters. The application of interlaced Superposition CNN-BiLSTM in SC reactive power output modelling is a new technology. The excitation voltage and excitation current of the SC are used as inputs for the training and testing sampled data, and the reactive power of the SC is used as outputs for the training and testing sampled data. Therefore, the reactive power output model of a SC in an UHVDC converter station based on interlaced superposition CNN-BiLSTM is obtained, and it attains a low root mean square error (RMSE = 0.126750) and a high determination coefficient (R 2 = 0.999999)
Multi-Physics Multi-Objective Optimal Design of Bearingless Switched Reluctance Motor Based on Finite-Element Method
Design of PV MVDC Converter with Wide Output Voltage Range for Series DC System
This paper presents a topology of PV MVDC converter with wide output voltage range for a series DC system and its control strategy. In the series DC system, the PV MVDC converters are input-independent, and their outputs are series-connected. A high-level system voltage is achieved for power collection and transmission. This series boost system is flexible and very suitable for decentralized renewable energy application. A modular topology is present for the MVDC converter to improve its applicability. A reconfigurable topology and its modulation method are proposed for the module of the converter. By regulating of duty cycle of switches, the module can be reconfigured to step-up or step-down mode. The operating principles and theoretical derivations of the reconfigurable topology are discussed in detail in this paper. Multimode control strategy for the converter is designed to adapt to complex operation conditions in a series DC system. With the proposed topology and control strategy, the series-connected PV MVDC converter achieves wide input and output voltage range to adapt to the operating characteristics of the series DC system; 3 kV/80 kW DC–DC module and 20 kV/500 kW PV MVDC converter are developed and operating stably in practice. The operation results are presented in the paper
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