Evaluation of lanthanum/iron oxide amended formable biochar for phosphorous and nitrogen removal in wastewater: preparation, mechanism, and application.

Doctoral Degree. University of KwaZulu-Natal, Pietermaritzburg.Abstract available in PDF

PV-SSD: A Projection and Voxel-based Double Branch Single-Stage 3D Object Detector

LIDAR-based 3D object detection and classification is crucial for autonomous driving. However, inference in real-time from extremely sparse 3D data poses a formidable challenge. To address this issue, a common approach is to project point clouds onto a bird's-eye or perspective view, effectively converting them into an image-like data format. However, this excessive compression of point cloud data often leads to the loss of information. This paper proposes a 3D object detector based on voxel and projection double branch feature extraction (PV-SSD) to address the problem of information loss. We add voxel features input containing rich local semantic information, which is fully fused with the projected features in the feature extraction stage to reduce the local information loss caused by projection. A good performance is achieved compared to the previous work. In addition, this paper makes the following contributions: 1) a voxel feature extraction method with variable receptive fields is proposed; 2) a feature point sampling method by weight sampling is used to filter out the feature points that are more conducive to the detection task; 3) the MSSFA module is proposed based on the SSFA module. To verify the effectiveness of our method, we designed comparison experiments

Degradable Nursery Containers Made of Rice Husk and Cornstarch Composites

The degradation behavior was investigated for eco-composite nursery containers (NCs) prepared with rice husk and cornstarch adhesive modified with urea formaldehyde (UF) as a wet strength agent. The wet shear strength, water absorption capacities, and biological degradation of NCs within soil were also investigated. Quantitative analysis of the thermal degradation behavior of different NC versions was performed by thermo-gravimetric analysis (TGA). The results demonstrated that the introduction of the UF agent accelerated the soil degradation of the NCs matrix to a certain extent. The maximum cumulative mass loss was 51.1% when the UF content of NCs was 8 wt.%. Moreover, the dry strength of the mixed urea formaldehyde-cornstarch adhesive (UCA) was increased by 108.9% compared with cornstarch adhesive (CA). The results of this work indicate the improved biodegradability of the NC eco-composites, which could make them potential sustainable alternatives for conventional plastic pots

How to Construct a Combined S-CO2 Cycle for Coal Fired Power Plant?

It is difficult to recover the residual heat from flue gas when supercritical carbon dioxide (S-CO2) cycle is used for a coal fired power plant, due to the higher CO2 temperature in tail flue and the limited air temperature in air preheater. The combined cycle is helpful for residual heat recovery. Thus, it is important to build an efficient bottom cycle. In this paper, we proposed a novel exergy destruction control strategy during residual heat recovery to equal and minimize the exergy destruction for different bottom cycles. Five bottom cycles are analyzed to identify their differences in thermal efficiencies (ηth,b), and the CO2 temperature entering the bottom cycle heater (T4b) etc. We show that the exergy destruction can be minimized by a suitable pinch temperature between flue gas and CO2 in the heater via adjusting T4b. Among the five bottom cycles, either the recompression cycle (RC) or the partial cooling cycle (PACC) exhibits good performance. The power generation efficiency is 47.04% when the vapor parameters of CO2 are 620/30 MPa, with the double-reheating-recompression cycle as the top cycle, and RC as the bottom cycle. Such efficiency is higher than that of the supercritical water cycle power plant

EFFECT OF VIRTUAL REALITY-BASED PREOPERATIVE VISIT ON PATIENTS WITH ELECTIVE CORONARY ARTERY BYPASS GRAFTING

Objective To explore the application effect of virtual reality (VR)-based preoperative visit on patients with elective coronary artery bypass grafting (CABG). Methods A total of 100 patients with coronary heart disease requiring CABG who were admitted to our hospital from June 2021 to June 2022 were included as the research subjects. The patients were divided into the control group and the experimental group according to the random number table method, with 50 patients in each group. The control group received conventional cardiovascular surgery preoperative visit, and the experimental group received VR-based preoperative visit. Before preoperative visit (on admission) and after preoperative visit (2 h before surgery), the heart rate, blood pressure, self-rating anxiety scale (SAS) score, visual analogue scale (VAS) appropriateness score, and interview satisfaction rate were measured and compared between the two groups. Results There were significant differences in heart rate, blood pressure, SAS score, VAS score, and interview satisfaction rate before and after the visit between the two groups (χ2=7.111,t=6.568-22.636,P<0.05). Conclusion Preoperative visit based on VR can help reduce the preoperative psychological stress of patients with elective CABG, and improve preoperative visit quality and preoperative comfort, which can be used as a reference

The complete chloroplast genome of weedy rye Secale cereale subsp. segetale

Weedy rye (Secale cereale subsp. segetale Zhukov 1928) is a problematic weed species in wheat field. However, it can potentially provide valuable genetics resources to increase the genetic variations and introduce desirable genes for rye and wheat breeding. Here, we assembled the complete chloroplast genome of S. cereale subsp. segetale. The chloroplast genome is 137,051 bp in length, containing a large single copy region (81,090 bp), a small single copy region (12,795 bp) and two separated inverted repeat regions (21,583 bp). A total of 131 unique genes were annotated, consisting of 82 protein-coding genes, 41 tRNA genes, and 8 rRNA genes. The phylogenetic analysis showed that Secale cereale subsp. segetale (weedy rye) and S. cereale subsp. cereale (rye) clustered together as sisters to other Secale species

Physical, Chemical, and Rheological Properties of Rice Husks Treated by Composting Process

A composting treatment was employed in an effort to improve the processability of rice husks. Changes in the chemical composition, physical structure, and rheological properties of modified rice husks were analyzed. The results indicated that the average diameter of compost-treated samples was significantly higher than that of the untreated samples because they were able to adhere to each other by the bacterial protein. Scanning electron microscopy images showed that the epidermis became rugged and lumpy because the composition of rice husks (cellulose, hemicellulose, lignin, and pectin) was partially decomposed, an effect confirmed by the chemical composition and FTIR analysis. Thermogravimetric analysis showed that the composted samples had better thermal stability than the untreated ones. Stress-strain curves showed that the treated samples displayed a moderately significant change of slope at about 0 to 10% strain, and they had better mechanical properties than untreated samples. Juxtaposing the rheological properties of both untreated and treated samples determined that the latter had higher apparent viscosity as a result of degradation and bacterial protein effects. All results indicated that the composting treatment changed the physical, chemical, and rheological properties of the rice husks, which are beneficial for its utilization and processability

Nutritional Value and Physicochemical Characteristics of Alternative Protein for Meat and Dairy—A Review

In order to alleviate the pressure on environmental resources faced by meat and dairy production and to satisfy the increasing demands of consumers for food safety and health, alternative proteins have drawn considerable attention in the food industry. However, despite the successive reports of alternative protein food, the processing and application foundation of alternative proteins for meat and dairy is still weak. This paper summarizes the nutritional composition and physicochemical characteristics of meat and dairy alternative proteins from four sources: plant proteins, fungal proteins, algal proteins and insect proteins. The difference between these alternative proteins to animal proteins, the effects of their structural features and environmental conditions on their properties, as well as the corresponding mechanism are compared and discussed. Though fungal proteins, algal proteins and insect proteins have shown some advantages over traditional plant proteins, such as the comparable protein content of insect proteins to meat, the better digestibility of fungal proteins and the better foaming properties of algal proteins, there is still a big gap between alternative proteins and meat and dairy proteins. In addition to needing to provide amino acid composition and digestibility similar to animal proteins, alternative proteins also face challenges such as maintaining good solubility and emulsion properties. Their nutritional and physicochemical properties still need thorough investigation, and for commercial application, it is important to develop and optimize industrial technology in alternative protein separation and modification

Oxidation Behavior and Mechanism of Al4SiC4 in MgO-C-Al4SiC4 System

Al4SiC4 powder with high purity was synthesized using the powder mixture of aluminum (Al), silicon (Si), and carbon (C) at 1800 °C in argon. Their oxidation behavior and mechanism in a MgO-C-Al4SiC4 system was investigated at 1400–1600 °C. XRD, SEM, and energy dispersive spectrometry (EDS) were adopted to analyze the microstructure and phase evolution. The results showed that the composition of oxidation products was closely related to the atom diffusion velocity and the compound oxide layer was generated on Al4SiC4 surface. In addition, the effect of different CO partial pressure on the oxidation of Al4SiC4 crystals was also studied by thermodynamic calculation. This work proves the great potential of Al4SiC4 in improving the MgO-C materials