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In recent years, along with the rapid growth of the number of agricultural machinery and equipment in China, the problems of high failure rate and low operational efficiency of agricultural machinery have gradually emerged. Therefore, how to diagnose and monitor the common faults of agricultural machinery in real time has become a hot spot for research on common faults of agricultural machinery. Based on the current technical requirements of fault diagnosis and monitoring of common faults of agricultural machinery, this paper designs and implements a vibration feature model based on the GDBT algorithm with the common faults of agricultural machinery as the monitoring object, and shows that the corresponding values of the fault size at 0.1 mm are equal to 8.1m/s2, and the corresponding effective values at the size of 2 mm are 34, 19 m/s2. And the vibration waveform is particularly similar to the trend of the fault, with the minimum values of 13 and 110 m/s2, respectively, both at the fault size of 0.5 mm.

Ferritin is an endogenous protein which is self-assembled by 24 subunits into a highly uniform nanocage structure. Due to the drug-encapsulating ability in the hollow inner cavity and abundant modification sites on the outer surface, ferritin nanocage has been demonstrated great potential to become a multi-functional nanomedicine platform. Its good biocompatibility, low toxicity and immunogenicity, intrinsic tumor-targeting ability, high stability, low cost and massive production, together make ferritin nanocage stand out from other nanocarriers. In this review, we summarized ferritin-based nanomedicine in field of disease diagnosis, treatment and prevention. The different types of drugs to be loaded in ferritin, as well as drug-loading methods were classified. The strategies for site-specific and non-specific functional modification of ferritin were investigated, then the application of ferritin for disease imaging, drug delivery and vaccine development were discussed. Finally, the challenges restricting the clinical translation of ferritin-based nanomedicines were analyzed.

Objective To explore the effect of long noncoding RNA cancer susceptibility 2 (lncRNA CASC2) on the sensitivity of glioma cells to temazolamide (TMZ) and investigate the underling mechanism. Methods Forty glioma tissue samples derived from the 40 patients undergoing surgical treatment in our department from July 2018 to March 2020 were enrolled in this study. The expression of lncRNA CASC2 in the glioma tissues was detected with RT-PCR, and the results were analyzed with pathological grades and compared between the patients with isocitrate dehydrogenase (IDH) 1/2 mutant (n=17) and IDH 1/2 wild type (n=9). Glioma cells U251 were cultured and transfected with plasmid pc-CASC2 to overexpress lncRNA CASC2 and/or interfering RNA of multi-drug resistance protein ABCG2. CCK-8 assay and flow cytometry were used to detect the cell viability and apoptotic rate in above cell groups after 30 μg/mL TMZ treatment. After mouse intracranial glioma model was established, high performance liquid chromatography was adopted to determine the concentration of TMZ. The correlation between lncRNA CASC2 and ABCG2 was detected by immunofluorescence staining and RNA immunoprecipitation. Results LncRNA CASC2 level was decreased in the glioma tissues with IDH 1/2 wild type, and had a negative correlation with pathological grade of glioma. LncRNA CASC2 overexpression resulted in significantly lower IC50 to TMZ (36.7±4.2 μg/mL) than the U251 cells after pc-Null transfection (t=4.41, P < 0.05). Under 30 μg/mL TMZ stimulation, the cell viability was reduced and the proportion of apoptotic cells was increased after lncRNA-CASC2 overexpression. In the mouse intracranial glioma model, the concentration of intracellular TMZ active product was increased after lncRNA-CASC2 overexpression. LncRNA CASC2 and ABCG2 were evenly distributed in the cytoplasm, and RNA immunoprecipitation showed that the content of lncRNA CASC2 in ABCG2 antibody group was higher than that in IgG control group. In addition, down-regulation of intracellular ABCG2 by siRNA decreased the TMZ sensitivity of U251 cells that could enhanced by lncRNA CASC2. Conclusion LncRNA CASC2 improves the sensitivity of glioma U251 cells to TMZ. However, ABCG2 inhibition by siRNA attenuates the above effects of lncRNA CASC2.

This study focuses on the common key technologies of "environmentally friendly and resource-saving" asphalt pavement. Reactive asphalt deodorizers react with volatile chemicals with irritating odors in asphalt under high temperature conditions, converting them into stable and non-volatile macromolecules to remove odors and achieve a deodorizing effect. A goal is to develop clean asphalt pavement materials with the main characteristics of "low consumption, low emissions, low pollution, high efficiency". In this experimental research, we used gas-emission detection devices and methods to detect and evaluate odor concentration, SO2, NO, volatile organic compounds, and other gases and volatile substances in the production and construction of clean asphalt and mixtures. By combining rheological experiments, mechanical experiments, and other means, this study investigates the effects of odor enhancers on the penetration, ductility, softening point, high-temperature rheological properties, construction, and workability of warm-mix asphalt and mixtures. Furthermore, infrared spectroscopy experiments are used to conduct in-depth research on the odor-enhancing mechanism of odor enhancers. The results indicate that the addition of odor enhancers has little effect on the penetration and softening point of asphalt and maintains the basic performance stability of asphalt. In terms of high-temperature rheological properties and construction workability, the addition of warm-mix agents has a significant impact on the high-temperature failure temperature and rotational viscosity of asphalt, while the influence of deodorizers is relatively small. At higher temperatures, the rotational viscosity increases with the increase in the amount of deodorant added. Functional group analysis shows that the newly added materials have little effect on the essential properties and chemical composition of asphalt. In addition, during the experimental process, it was found that the coupling effect and other chemical reactions between the deodorizing agent and the warm-mixing agent can effectively improve the degradation effect of harmful gases. After the coupling action of deodorant and the warm-mixing agent, the degradation rate of harmful gas can be increased by 5–20%, ensuring the stable performance of asphalt. The performance of powder deodorizing agent is better than that of liquid deodorizing agent, and an increase in the dosage of deodorizing agent will enhance the degradation effect. This study provides an important basis for a deeper understanding of the performance of warm-mix and odorless modified asphalt. [ABSTRACT FROM AUTHOR]

Conventional straight fin (SF) radiators have difficulties meeting the cooling requirements of high-power electronic components. Therefore, based on the structure and technology of the detachable fin radiator, this paper proposes a kind of radiator embedded in the heat pipe base and uses the roll-bond flat heat pipe (RBFHP) to replace the traditional fin. The radiator has the advantages of modularity, easy manufacturing, low cost and good heat balance. In this study, the heat pipes (HPs)-RBFHPs radiator was tested in natural convection and forced convection to mimic the actual application scenario and compared with the conventional aluminum radiator. Heating power, angle, wind speed and other aspects were studied. The results showed that the cooling performance of the HPs-RBFHPs radiator was improved by 10.7% to 55% compared with that of the SF radiator under different working conditions. The minimum total thermal resistance in the horizontal state was only 0.37 °C/W. The temperature equalization of the base played a dominant role in the performance of the radiator at a large angle, and the fin group could be ineffective when the angle was greater than 60°. Under the most economical conditions with an inclination of 0° and a wind speed of 2 m/s, the input power was 340 W, the heat source temperature of the HPs-RBFHPs was only 64.2 °C, and the heat dissipation performance was 55.4% higher than that of SFs. [ABSTRACT FROM AUTHOR]

The differential settlement between bridge approach slab and abutment causes bump problems when vehicles passing this area. This study aims at evaluating the roughness of area between road-bridge transition properly and putting forward the allowable differential settlement value based on the comfortable feeling of passengers. In this research, the maximum transient vibration value (MTVV) was chosen to be the evaluation index of roughness vibration comfort, and full-car model and bridge approach pavement models were established using Carsim software. Then, the interactions of human-vehicle-road were simulated when the car passed the bridge at different speeds, and the influences of step height, approach slab length, approach relative slope and vehicle speed on MTVV were studied. According to the simulation results and the comfortable feeling questionnaire when a testing car passed different bridge areas, the specific grading standard of MTVV was given, and for the bridge with and without approach slab, the allowable differential slope and the step height of the bridge under difference were put forward. The results have a significant value for the roughness evaluation of the road-bridge transition area and can be used to judge whether this area is needed or not to maintain. [ABSTRACT FROM AUTHOR]

Chemical warfare agents (CWAs) still threaten society and have been used in recent terrorist attacks. Various adsorbents have been developed to remove CWA droplets effectively from contaminated objects to protect against serious injury. In this project, a collection of textiles, zirconium hydroxide (ZH) combined with polyvinyl alcohol (PVA)-polyethylene glycol (PEG) or polyacrylonitrile (PAN), were prepared using electro-spinning. Results of scanning electron microscopy, X-ray diffraction and inductively coupled plasma optical emission spectroscopy indicated that ZH was uniformly distributed and attached in the interstices of the polymer fiber with a high Zr load ratio of >24%. The wetting and absorption of ZH textiles to simulation agents such as 2-chloroethyl ethyl sulfide and dimethyl methylphosphate showed good performance in terms of absorption. The calculation results, where the absorption factor ka of each textile was a constant value, suggested they had excellent capacity of removing CWA droplets, such as bis(2-chloroethyl) sulfide (HD), S-2-(diisopropylamino) ethyl O-ethyl methylphosphonothioate (VX) and pinacolyl methylphosphonofluoridate (GD). The detoxification experiment showed that both textiles of ZH@PAN and PAN had optimum degradation of HD with half-lives of 84.5 min due to its fast natural hydrolysis of HD and good adsorption of HD on textile. For degradation of VX solution, ZH@PVA-PEG presented a strong degradation capability with an almost equal half-life of 64.5 min to ZH. ZH@PVA-PEG could also catalyze GD hydrolysis effectively with a half-life of 55.0 min. This work manifested the possibility for quick absorption of CWAs from contaminated objects with non-powder materials and a strong degradation ability. [ABSTRACT FROM AUTHOR]

Toxicity, emissions and structural damage results on lithium-ion battery (LIB) thermal runaway triggered by the electrothermal method were performed in this work. The electrothermal triggering method was determined to study the thermal runaway behaviors of three types of commercial LIBs. The structural damage of the cathode material of the batteries after thermal runaway was observed by scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray diffraction (XRD). It was found that as the state of charge (SOC) of the battery increases, the lower the temperature at which thermal runaway occurs, and the more badly the structural damage of the electrode material after thermal runaway. Qualitative analysis of products from LIBs thermal runaway emissions was conducted by GC-MS, and the toxicity and formation mechanism of the emissions were analyzed in detail. Dozens of toxic substances were detected from the emissions after thermal runaway of batteries using LixNi1/3Co1/3Mn1/3O2 and LiCoO2 as the cathode material, the types of toxic substances increase gradually with the increase in the SOC, while as for batteries using LiFePO4 as the cathode material, most types of toxic substances were detected from 30% SOC. [ABSTRACT FROM AUTHOR]

To analyze the dynamic response of the deck pavement of continuous box girder bridge with variable section corrugated steel webs (CBB) under moving loads, a three-dimensional (3D) finite element model of three-span CBB superstructure was established using the finite element software ABAQUS. The validity of the 3D finite element model was verified by the field static load test data. Five vehicle speeds (40 km/h, 60 km/h, 80 km/h, 100 km/h, and 120 km/h), four types of axle loads (5 kN, 25 kN, 30 kN, and 40 kN), and three kinds of load positions were selected. The dynamic responses of the CBB deck pavement, displacement, stress, acceleration, and impact coefficient were calculated. The results showed that under the action of moving loads, the maximum values of vertical displacement and vertical stress appeared on the top surface of deck pavement. The longitudinal shear stress of deck pavement of CBB increased with the increase of pavement depth, and it reached the maximum value at the top of concrete pavement. With the increase of vehicle speed, the impact coefficient, vertical displacement, and transverse stress of the top surface of deck pavement gradually decreased, which indicated that the stress of deck pavement was significantly impacted by the vehicle speed and axle load, while its vertical displacement was less influenced. Under the eccentric load, the large transverse torsion would be produced in the CBB and the more the load deviates from the centerline of the cross section of the CBB, the greater the vibration amplitude of the vertical acceleration generated by the mid-span node on the surface of the deck pavement. Therefore, the low vehicle speed and eccentric load had a great impact on the structural safety response of deck pavement. In practical engineering, it is necessary to avoid vehicles driving at low speeds on one side of the bridge. [ABSTRACT FROM AUTHOR]

Pixelated CdZnTe detectors mymargin have achieved excellent spectroscopic performance and showed the advanced capability of coded-aperture and Compton imaging. Subpixel sensing is a technique to improve their imaging capabilities. For single-pixel-triggered events, subpixel sensing was demonstrated years ago. This article proposes a method to calculate subpixel location for two-pixel-triggered charge-sharing events. [ABSTRACT FROM AUTHOR]