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The simultaneous downstream valorization of cellulose and lignin is an important aspect of efficiently extracting value from lignocellulose. The present work, we demonstrated the preparation of a novel bio-based filler by the co-assembly of cellulose and lignin obtained from a one-pot ethanosolv lignocellulose fractionation process. The cellulose was valorized by forming cellulose nanocrystals (CNCs) through simple bleaching and ultrasonication processes. The lignin fractions demonstrated greater solubility (19.2 mg/mL) and lower molecular weight (6980 g/mol) than conventional industrial lignins. Various lignin@CNCs specimens were prepared via a facile co-assembly of the lignin and CNCs. These entirely bio-based materials could be used as a multifunctional filler to enhance the properties of a waterborne coating (WBC). Specifically, the mechanical properties, coating performance and ultraviolet resistance of a WBC were all significantly improved, demonstrating a synergistic enhancement effect obtained from the CNCs and lignin. In this manner, both cellulose and lignin components were efficiently transformed to value-added fillers for WBC, demonstrating a highly efficient pathway for lignocellulose utilization and downstream value-added applications.

The paper proposes a new Vector Analysis based Model Predictive Control (VAMPC) method for multilevel converters with four different switching configurations. It is based on track of an error vector using fundamental state vectors, and can achieve deadbeat control of four switching states multilevel converters with multiple control objectives. Compared with conventional finite control set model predictive control (FCS-MPC) method, VAMPC can achieve excellent spectrum characteristics in the case of a slight increase in computational burden. The VAMPC method is experimentally validated on a 100 kHz GaN-based 3-level flying capacitor (FC) converter. Compared with the FCS-MPC, VAMPC leads to significant reduction in steady-state control errors. For example, the inductor current total harmonic distortion (THD) of the FC converter is now reduced by more than 60%.

For a flying capacitor multilevel converter (FCMC), prompt detection of power switch failures is crucial for fault-tolerant operation. This paper presents a new technology for identifying and locating faulty cells in FCMC. Mathematical derivation points out that different fault types and locations will present different high-frequency harmonics. The new technology extracts high-frequency harmonics in the switch node voltage and look up a pre-established table to identify the fault type and location. The discrete Fourier transform (DFT) can be easily performed to analyze the harmonic using the built-in IP core in Field Programmable Gate Array (FPGA). For a FCMC with any number of levels, the new approach requires only one voltage sensor, and can accurately locate the faulty cell after one carrier cycle when the fault occurs. Both simulation and experimental results validate the proposed concept on a 5-level 100 kHz GaN FET based FCMC prototype. Furthermore, we have experimentally demonstrated fault-tolerant operation of the FCMC after a switch short and open fault is detected and identified by the new technique.

Based on a literature review of influencing factors and forecasting methods for grain production, the empirical analysis of the influencing factors of China’s grain output is performed using the full subset regression method, the ridge regression method, and the LASSO regression method. The results show that (1) the increase in the sown area of grain crops is the main reason for the increase in grain output, (2) the use of agricultural fertilizers and the increase in rural electricity consumption are the driving factors for the increase in grain output, (3) the impact of total power of agricultural machinery is limited, and (4) natural disasters have a certain negative impact on food production.

Stepper motor is an actuator for converting electric pulse signal into angular displacement, which is characterized by no cumulative error, low mature price and good stability, which is widely used in various industrial environments. However, its disadvantage is also very obvious, that is, can only open loop control, the motor can only passively rotate according to the signal and cannot effectively feedback control.If closed-loop control is required, servo motors with higher price and larger volume are required. In order to solve this problem, this paper refits the stepping motor with the help of the characteristics of the magnetic encoder, so as to realize the closed-loop control of the stepping motor.

Clarifying the deformation behaviors of microstructures could greatly help us understand the precipitation-strengthening mechanism in alloys. However, it is still a formidable challenge to study the slow plastic deformation of alloys at the atomic scale. In this work, the phase-field crystal method was used to investigate the interactions between precipitates, grain boundary, and dislocation during the deformation processes at different degrees of lattice misfits and strain rates. The results demonstrate that the pinning effect of precipitates becomes increasingly strong with the increase of lattice misfit at relatively slow deformation with a strain rate of 10−4. The cut regimen prevails under the interaction between coherent precipitates and dislocations. In the case of a large lattice misfit of 19.3%, the dislocations tend to move toward the incoherent phase interface and are absorbed. The deformation behavior of the precipitate-matrix phase interface was also investigated. Collaborative deformation is observed in coherent and semi-coherent interfaces, while incoherent precipitate deforms independently of the matrix grains. The faster deformations (strain rate is 10−2) with different lattice misfits all are characterized by the generation of a large number of dislocations and vacancies. The results contribute to important insights into the fundamental issue about how the microstructures of precipitation-strengthening alloys deform collaboratively or independently under different lattice misfits and deformation rates.

In this article, two continuous control set model predictive control (CCS-MPC) methods with one-step prediction horizon for three-level flying capacitor boost converter (FCBC) that can provide constant switching frequency are presented. The first one is explicit model predictive control (EMPC), which can provide explicit solution. In order to further reduce the complexity and the computational burden of EMPC while meeting the control requirements, a simple model predictive control (SMPC) is proposed as the second CCS-MPC method. The proposed CCS-MPC will be used as the inner-loop controller to control the inductor current and flying capacitor (FC) voltage. Besides, a suitable outer-loop control strategy for the output voltage is proposed to provide a suitable inductor current reference to improve the dynamic response of the output voltage while avoiding overcurrent. Compared with the previous control method for three-level FCBC, the proposed control method has good dynamic performance and stronger ability to resist input voltage disturbance. The effectiveness of the proposed method is verified by simulation and experimental results.

In this study, the effects of hot-rolled processes at different temperatures (420 °C, 450 °C, and 480 °C) and subsequent solid solution and aging treatments on the microstructure, mechanical properties, and corrosion properties of Al-Mg-Li alloys with trace Sc and Zr addition were investigated. The aging treatment of rolled sheets after solid solution treatment could obtain Al3Li particles and Al3(Sc, Zr)/Al3Li core–shell particles to improve the mechanical properties of Al-Mg-Li alloy products effectively. The results showed that, as the rolling temperatures increased from 420 °C to 480 °C, the alloy’s ultimate tensile strengths and yield strengths increased, while the corrosion resistance decreased. The increase in rolling temperature increased the precipitation-free zone (PFZ) width of the alloy, which undermined the corrosion resistance of the alloy. Moreover, elevating the hot rolling temperature changes the texture strength of the alloy. Particularly in the 480 °C hot-rolled sample, the decrease in the Brass texture strength and the increase in the S texture and Copper texture strength led to an increase in the Taylor factor (M). The increase in rolling temperature also raised the number density of the Al3(Sc, Zr)/Al3Li core–shell particles. The presence of such particles not only inhibits grain growth but also changes the strength mechanism from dislocation cutting to Orowan bypassing. Due to the combination effect of grain morphology, texture evolution, and precipitation behavior, the 480 °C hot-rolled sample had the highest properties.

Objectives: In recent years, science and technology financial support industries are actively supporting the innovation and development of high-tech industries. In order to test the actual effect of S&T financial support industry support plan, a GARCH (Generalized AutoRegressive Conditional Heteroskedasticity) model is designed by using K-means (K-means clustering) algorithm and GM (1,1) (grey prediction) algorithm, which can quantitatively display the development of S&T financial industry to promote high-tech. The GARCH model is used to quantify the degree of innovation and development of science and technology finance industry in the Internet of Things (loT) technology. Finally, according to the quantitative data obtained by GARCH (Generalized AutoRegressive Conditional Heteroskedasticity) model, the actual effect of science and technology finance industry promoting innovation and development of high-tech is evaluated by FAHP (Fuzzy Analytic Hierarchy Process) model. The results show that science and technology finance industry plays a positive role in promoting the innovation and development of loT technology.

Prompt detection of power switch failure is crucial for fault-tolerant operation of multilevel converters. This article presents a new technique of detecting, identifying, and locating a device fault in a multilevel dc–dc flying capacitor (FC) buck converter (FCBC). This is realized by continuously analyzing the magnetic component (inductor or transformer) voltage harmonics for failure detection and subsequently identifying failure type and location with a look up table method. The harmonics analysis is performed by the existing FPGA controller using discrete Fourier transform (DFT). This new approach uses an auxiliary winding in the existing inductor core without adding any new hardware and can identify the location and fault type with good accuracy and speed. The experimental results validate the proposed concept on a three-level GaN-based FCBC prototype.

Since it affects a nation’s economy and people’s wellbeing, food security is a crucial national security requirement. In order to realize multi-angle grain data presentation and analysis and achieve the goal of deep mining, we propose a 3D dynamic visualization analysis method of multidimensional agricultural spatial–temporal data based on the self-organizing map. This method realizes the multi-angle display and analysis of grain data and achieves the purpose of deep mining. With the outbreak of COVID-19, the global food security situation is not optimistic, so it is necessary to use the food security early warning system to solve the food security issue. Machine learning has emerged widely in recent years and has been applied in various fields. Therefore, it is an excellent way to solve food security to apply the model in machine learning to construct a food security early warning system. Afterward, a food security early warning platform is developed with a support vector regression (SVR) model to ensure food security. Finally, we analyze China’s medium and long-term food security policy in line with modernization objectives. The experimental results show that the food security early warning platform based on the SVR model from 2007 to 2016 is effective compared with the actual situation every year. Through analyses, we should improve the stability, reliability, and sustainability of food supply, firmly hold the food security initiative, and construct a national food security guarantee system matching the goal of modernization.

Nucleation, significantly influenced by local structures in metallic melts, is crucial for controlling the microstructure of solidified materials. However, the connection between local atomic struc...

Wide bandgap (WBG) power semiconductors offer lower switching loss and higher power density than silicon but suffer from significantly higher cost. In this article, we introduce a design methodology which uses a low-frequency silicon base power processor to achieve high efficiency and low cost, and a high-frequency WBG fractional power active filter to reduce harmonics and achieve high power quality. The mixed use of WBG and Si delivers the same WBG benefits but at a reduced component cost. A boost PFC converter based on this design principle is reported that comprises two interleaved Si and GaN phases. We develop a new unified control strategy to allow the base power processed efficiently by the Si phase switching at a low frequency of 10 kHz and the harmonics to be minimized by the MHz-frequency GaN phase as an active filter. A 2.1-kW Si/GaN interleaved PFC prototype exhibits a peak efficiency of 98.04% and a power factor of 0.998, even with a frontend diode bridge. The new interleaved PFC is validated by simulation and experimentally to achieve excellent efficiency, power density, and harmonics mitigation at a cost much lower than a full-scale WBG design.

Formation of quasicrystal structures has always been mysterious since the discovery of these magic structures. In this work, the nucleation of decagonal, dodecagonal, heptagonal, and octagonal quasicrystal structures controlled by the coupling among multiple length scales is investigated using a dynamic phase-field crystal model. We observe that the nucleation of quasicrystals proceeds through local rearrangement of length scales, i.e., the generation, merging and stacking of 3-atom building blocks constructed by the length scales, and accordingly, propose a geometric model to describe the cooperation of length scales during structural transformation in quasicrystal nucleation. Essentially, such cooperation is crucial to quasicrystal formation, and controlled by the match and balance between length scales. These findings clarify the scenario and microscopic mechanism of the structural evolution during quasicrystal nucleation, and help us to understand the common rule for the formation of periodic crystal and quasicrystal structures with various symmetries.

Cascaded boost-buck PFC (CBBPFC) converters offer a wide voltage conversion ratio and a near-unity power factor but require a large output electrolytic capacitor, leading to poor reliability and power density. In this paper, a coordinated two-stage operation and control strategy is proposed to significantly minimize the capacitor requirement without any other hardware changes. In a conventional CBBPFC converter, the boost and buck stages either operate independently nor complementally. In contrast, the proposed method operates the two stages in a concerted manner, so it is possible to use the dc-link capacitor with certain voltage fluctuation to buffer the power imbalance between the AC input and DC output. A new coordinated control strategy and a fluctuation-ratio based design consideration are developed to coordinate the operation of the two stages, further complement the system design. A 200W CBBPFC prototype based on the design concept exhibits a maximum reduction of the output capacitor by 83%, a peak efficiency of 95.8%, and a power factor of 0.99.

After decades of advance development, China's stock market has gradually arisen into one of the world's most important capital markets. The stock price index can well reflect the health status and macro change trend of a country's economic development, which can be said to be a barometer of the country's economic development. Studying the stock price index forecast is of great significance to the entire national economy and to each investor. Using 2 tools, Python and EViews8.0, and taking the Shanghai Stock Exchange 50 index as an example, the long short-term memory (LSTM) model in deep learning (DL) and the Autoregressive Integrated Moving Average (ARIMA) model are selected for fitting and prediction. The research results explain that the Root Mean Squared Error (RMSE) of LSTM model is lower, and the model based on DL method has stronger prediction ability on stock price index than traditional stock prediction model. This model is an effective stock prediction method.

The efficient recycling of valuable resources from rolling oil sludge (ROS) to gain new uses remains a formidable challenge. In this study, we reported the recycling of solid Fe resources from ROS by a catalytic hydrogenation technique and its catalytic performance for CO oxidation. The solid Fe resources, after calcination in air (Fe2O3-H), exhibited comparable activity to those prepared by the calcinations of ferric nitrate (Fe2O3-C), suggesting that the solid resources have excellent recycling value when used as raw materials for CO oxidation catalyst preparation. Further studies to improve the catalytic performance by supporting the materials on high surface area 13X zeolite and by pretreating the materials with CO atmosphere, showed that the CO pretreatment greatly improved the CO oxidation activity and the best activity was achieved on the 20 wt.%Fe2O3-H/13X sample with complete CO conversion at 250 °C. CO pretreatment could produce more oxygen vacancies, facilitating O2 activation, and thus accelerate the CO oxidation reaction rate. The excellent reducibility and sufficient O2 adsorption amount were also favorable for its performance. The recycling of solid Fe resources from ROS is quite promising for CO oxidation applications.

Background miR-100 has been reported to closely associate with gastric cancer (GC) initiation and progression. However, the underlying mechanism of miR-100-3p in GC is still largely unclear. In this study, we intend to study how miR-100-3p regulates GC malignancy. Methods The expression levels of miR-100-3p in vitro (GES-1 and GC cell lines) and in vivo (cancerous and normal gastric tissues) were examined by quantitative real-time PCR (qRT-PCR). MTT and PE/Annexin V analyses were responsible for measurement of the effects of miR-100-3p on GC cell proliferation and apoptosis. Transwell assay with or without matrigel was used to examine the capacity of migration and invasion in GC cells. The interaction of miR-100-3p with bone morphogenetic protein receptor 2 (BMPR2) was confirmed through transcriptomics analysis and luciferase reporter assay. qRT-PCR and Western blot analyses were applied to determine the expression of ERK/AKT and Bax/Bcl2/Caspase3, which were responsible for the dysfunction of miR-100-3p. Results miR-100-3p was down-regulated in GC cell lines and cancerous tissues, and was negatively correlated with BMPR2. Loss of miR-100-3p promoted tumor growth and BMPR2 expression. Consistently, the effects of miR-100-3p inhibition on GC cells were partially neutralized by knockdown of BMPR2. Over-expression of miR-100-3p simultaneously inhibited tumor growth and down-regulated BMPR2 expression. Consistently, over-expression of BMPR2 partially neutralized the effects of miR-100-3p over-expression. Further study demonstrated that BMPR2 mediated the effects downstream of miR-100-3p, which might indirectly regulate ERK/AKT and Bax/Bcl2/Caspase3 signaling pathways. Conclusion miR-100-3p acted as a tumor-suppressor miRNA that down-regulated BMPR2, which consequently inhibited the ERK/AKT signaling and activated Bax/Bcl2/Caspase3 signaling. This finding provided novel insights into GC and could contribute to identify a new diagnostic and therapeutic target.

Gd(III) containing wastewater has toxic effects on both public health and aquatic life. However, few literature is available using wastes biomass containing cellulose with enough high adsorption capacity to remove Gd(III). Herein, we described a facile synthesis of triazole and carboxyl- functionalized magnetic cellulose-based material from ramie stalk (TCM-RS) through click chemistry strategy for the first time. The synthesized sample (TCM-RS) was used as an efficient adsorbent for the removal of Gd(III) from aqueous solution. The obtained materials were well characterized. Batch adsorption experiments showed that the combination of bifunctional chelating ligand, sufficient specific surface area, and magnetic response endowed the adsorbent with excellent adsorption selectivity, high adsorption capacity and easy separation of adsorbent from solutions, respectively. The maximum Gd(III) uptake of TCM-RS (62.8 mg/g) was reached within 40 min. Adsorption isotherms and kinetics revealed that the Langmuir model and the pseudo-second-order kinetics model could well describe the adsorption process of Gd(III) onto TCM-RS. Moreover, the sorbent can be regenerated and reused for five cycles without significant loss in adsorption capacity. Our study not only provides new insights into the fabrication of TCM-RS through click chemistry strategy, but also reveal that TCM-RS has great potential application for the removal of Gd(III) from wastewater.