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Catalysts ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 66
Author(s):  
Xingyuan Gao ◽  
Jinglong Liang ◽  
Liqing Wu ◽  
Lixia Wu ◽  
Sibudjing Kawi

CO2 hydrogenation is an effective way to convert CO2 to value-added chemicals (e.g., CH4 and CH3OH). As a thermal catalytic process, it suffers from dissatisfactory catalytic performances (low conversion/selectivity and poor stability) and high energy input. By utilizing the dielectric barrier discharge (DBD) technology, the catalyst and plasma could generate a synergy, activating the whole process in a mild condition, and enhancing the conversion efficiency of CO2 and selectivity of targeted product. In this review, a comprehensive summary of the applications of DBD plasma in catalytic CO2 hydrogenation is provided in detail. Moreover, the state-of-the-art design of the reactor and optimization of reaction parameters are discussed. Furthermore, several mechanisms based on simulations and experiments are provided. In the end, the existing challenges of this hybrid system and corresponding solutions are proposed.


OCL ◽  
2022 ◽  
Vol 29 ◽  
pp. 1
Author(s):  
Camille Dumont

Therapeutic peptides can treat a wide variety of diseases with selective and potent action. Their oral bioavailability is strongly limited by an important proteolytic activity in the intestinal lumen and poor permeation across the intestinal border. We have evaluated the capacity of solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) to overcome both oral bioavailability limiting aspects, using leuprolide (LEU) as model peptide. Lipidization of LEU by formation of a hydrophobic ion pair (HIP) with sodium docusate enables a significant increase of peptide encapsulation efficiency in both SLN and NLC. The nanocarriers, obtained by high-pressure homogenization, measured 120 nm and were platelet shaped. Regarding the protective effect towards proteolytic degradation, only NLC maintained LEU integrity in presence of trypsin. Intestinal transport, evaluated on Caco-2 (enterocyte-like model) and Caco-2/HT29-MTX (mucin-secreting model) monolayers, showed nanocarriers internalization by enterocytes but no improvement of LEU permeability. Indeed, the combination of nanoparticles platelet-shape with the poor stability of the HIP in the transport medium induces a high burst release of the peptide, limiting nanoparticles capacity to transport LEU across the intestinal border. Stability of peptide lipidization needs to be improved to withstand biorelevant medium to benefit from the advantages of encapsulation in solid lipid nanocarriers and consequently improve their oral bioavailability.


Author(s):  
Guofeng Zhang ◽  
Linqi Huang ◽  
Fuchao Yang

Photochromic materials with anti-water properties have impressed practical values, but their applications are severely hindered by poor stability and slow colour-switching rate. Inspired by the superhydrophobicity of lotus leaf and...


Author(s):  
Chen Qian ◽  
Jianjun Li ◽  
Kaiwen Sun ◽  
Chenhui Jiang ◽  
Jialiang Huang ◽  
...  

Antimony selenosulfide, Sb2(S,Se)3, has emerged as a promising light-harvesting material for its high absorption coefficient, suitable bandgap, low-toxic and low-cost constituents. However, the poor stability and high cost of widely...


2022 ◽  
Author(s):  
Feng-Wei Huang ◽  
Ke Ma ◽  
Xiu-Wen Ni ◽  
Sheng-Lin Qiao ◽  
Kezheng Chen

Laccase catalyzed colorimetric biosensing approach is promising for pheochromocytoma biomarker detection yet suffer from enzyme poor stability and high cost for production. here we report for the first time an...


Author(s):  
Xun-Lei Ding ◽  
Zhengyang Gao ◽  
Gaungyang Mao ◽  
Shengyi Chen ◽  
Yang Bai ◽  
...  

Perovskite solar cells (PSCs) have been intensively investigated and made great progress due to their high photoelectric conversion efficiency and low production cost. However, poor stability and the toxicity of...


2021 ◽  
Vol 13 (1) ◽  
pp. 12
Author(s):  
Yaowei Li ◽  
Liguo Zang ◽  
Tuo Shi ◽  
Tian Lv ◽  
Fen Lin

The traditional chassis has the problems of low trafficability and poor stability under complex and changeable unstructured conditions. Thus, a wheel rail composite chassis is proposed. The chassis had a tracked travel mechanism at the front wheels and a wheeled travel mechanism at the rear wheels. This study presents the design, theoretical analysis and dynamic simulation analysis of the chassis. The maximum values of the passability of the wheel–track composite chassis that can be passed were calculated according to the relevant parameters. Furthermore, the chassis was modeled and simulated using RecurDyn to verify whether the values were reasonable. According to different values of the terrain, slope, vertical obstacle height and trench width, the change regularity of the track tension and driving torque of the chassis were obtained. The chassis is designed to improve the vehicle’s ability to operate under complex and diverse unstructured conditions.


2021 ◽  
Vol 2021 ◽  
pp. 1-20
Author(s):  
Yu Li ◽  
Zhong Tang ◽  
Xinzhong Wang ◽  
Hao Zhang ◽  
Yaoming Li

Transmission modes of multiple rotating parts on combine harvester are complex and diverse, which resulted in large vibration and poor stability when the entire machine is harvesting. Aiming at the complex vibration problem of the combine harvester threshing system, this paper established the dynamic response model of the multidrum parallel system under different transmission modes and solved the vibration characteristics of the system. An experiment on the axial unbalance response of the parallel drum system under different transmission modes was carried out. The results show that the internal units of the threshing system form a whole through the transmission system, which causes the unbalanced response of the system to be superimposed on parallel threshing drums, thereby increasing the vibration amplitude. In addition, the change of the transmission mode will cause the vibration transmission path in the system to change greatly, and the boundary conditions of the system will be changed at the same time, which will eventually lead to the change of the unbalanced response characteristics.


2021 ◽  
Vol 12 ◽  
Author(s):  
Akanksha Patel ◽  
Abhay Dharamsi

Abstract: Poor solubility of a drug is one of the major concerns in drug delivery. Many strategies have been employed for solving this problem, but there are still some deficiencies with current strategies, such as low drug loading, high toxicity, poor stability, potential drug loss during storage and complex manufacturing method. By formulating nanocrystals, problems associated with the delivery of drugs with low water or lipid solubility can be addressed. Unlike polymeric nanoparticles and lipidic nanoparticles, they are not a reservoir or matrix system. Nanocrystals are colloidal suspensions of nanosized particles stabilized by polymeric or electrostatic stabilization. They can be prepared by Top-down or Bottom-up approaches. Some of the methods for the preparation of nanocrystals are nanoprecipitation, media milling, high-pressure homogenization, emulsions and microemulsions as templates, supercritical fluid technology and co-grinding. They can be used for oral, intravenous, ocular, inhalation, intramuscular drug delivery and drug targeting.


2021 ◽  
Vol 11 (24) ◽  
pp. 12058
Author(s):  
Liangliang Li ◽  
Jie Chen ◽  
Chen Ma ◽  
Hewei Meng ◽  
Jiangtao Qi ◽  
...  

In order to solve the problems of serious soil reflux and poor stability of ditch depth in the existing ditching organic fertilizer fertilization device in grey desert and loess orchards, rotary tillage theory and software simulation were used to conduct kinematic analysis of soil particles and ditching blade in the ditching process, and meanwhile, modeling and simulation are carried out for sand soil particles by using EDEM software, so as to determine the action mechanism of soil, blade and fairing in ditching process of grey desert and loess. The abstract on this basis, the quadratic orthogonal regression-rotation combination experiment was designed. The soil bin test was carried out by taking the cutter wheel speed, ditching depth and inclination of curved surface as the influencing factors, and the throwing distance and the stability of ditch depth as the test indexes. And it was concluded that the order of the influence of the operating parameters of the ditching device on the soil throwing distance is ditching depth > inclination of curved surface > cutter speed, and the order of the influence on the stability of the ditch depth is ditching depth > cutter speed > Inclination of curved surface. Finally, the optimized operating parameters of the ditching device are as follows: the cutter wheel speed is 119.61 r·min−1, the inclination of curved surface is 30.07°, the ditching depth is 35.52 mm, the soil throwing distance is 57.31, and the stability of ditch depth is 87.43. With these parameters as test objects, 10 groups of single factor tests were carried out to obtain that the soil throwing distance is 58.33, and the stability of ditch depth is 86.51, which were basically consistent with the expected results of the optimization test, and also in line with the relevant agronomic standards.


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