Sample Preparation Methods Affect Engineering Characteristic Tests of Municipal Solid Waste

The output of municipal solid waste (MSW) has sharply increased over the recent years, which induces many severe problems (environmental pollution, deteriorating human health, and increased land occupation). Engineering parameters form the research basis for MSW treatment, which can be greatly influenced by the applied sample preparation methods. Currently, the preparation method of MSW samples mostly refers to the geotechnical test standard. The suitability and accuracy of this method for MSW are less studied, especially when considering biodegradation, so further research is needed. Depending on whether the material is dried or remains wet during preparation, the samples made by traditional geotechnical test standards are referred to as dry method samples or wet method samples, respectively. To study the influence of the sample preparation methods on the MSW engineering properties of MSW, the compression tests, direct shear tests, and biodegradation compression tests were conducted for both types of samples (dry and wet). The results show that the data dispersion of the wet method samples is stronger. The average test data variance of wet samples was 1.43–8.85 times higher than that of dry samples. In both the direct shear test and the compression test, the differences in engineering parameters caused by the sample preparation method were less than 12.3% and 8.9%, respectively. In biodegradation compression tests, the difference in engineering parameters reached up to 33.7%. In general, the dry method is preferred for tests that do not consider biodegradation, while the wet method is more suitable for tests that consider biodegradation. The research can be used as a reference toward improving the simplicity and accuracy of MSW tests

Study on Restoration Materials for Historical Silty Earthen Sites Based on Lime and Starch Ether

The relics built with soil are called earthen archaeological sites. Many silt earthen sites exposed to natural environment get seriously damaged and thus require urgent restoration with suitable materials. Previously, lime and glutinous rice slurry were used in the construction of earthen sites. However, lime is usually used in clay, and glutinous rice pulp is difficult to prepare and use on a large scale. Therefore, in this study, starch ether was selected to replace glutinous rice pulp. Lime and starch ether were added to silt as single or double additives, respectively, to prepare the corresponding single-mixed and multiple-mixed modified soil samples. Furthermore, the direct shear test and compression test were carried out and the optimum content was determined. The strength and durability of optimum modified materials were compared with those of the original site soil. When the lime content was 9% or the concentration of starch ether solution was 5%, the shear strength and compression resistance ability of single-mixed modified soil were improved significantly. When lime content was 6% and starch ether solution was 5%, the strength of multiple-mixed modified soil was the best, and the maximum cohesion and internal friction angle were 51.1 and 3.37% higher than those of single-mixed soil, respectively. The strength and durability of the optimum modified soil were similar to or higher than those of the site soil. Thus, it is feasible and effective to use lime together with starch ether as restoration material for silty earthen sites

Response of Acid and Alkaline Phosphatase Activities to Copper Exposure and Recovery in Freshwater Fish Carassius auratus gibelio var

Abstract: Phosphatase is known to be sensitive to metal exposures and can be used to predict metal toxicity. In this study, freshwater fish Carassius auratus gibelio var were exposed to different concentrations (0.1, 0.2, 0.5, 1.0 and 2.0mg/L) of copper for 96 h, and the group of 2.0 mg/L exposure was then transferred to clean water for different days (1, 4, 8 and 12d) to assess recovery profile. Responses of acid phosphatase (ACP) and alkaline phosphatase (ALP) activities from kidney, liver, gill, spleen, muscle and brain to copper exposure and recovery were investigated. As shown from the results, after a 96-h copper exposure, ACP and ALP activities in different organs/tissues appeared to be different. At the highest copper concentration (2.0 mg/L), compared with the control, ACP activity decreased significantly in kidney, liver, gill and spleen, but increased significantly in muscle and brain. ALP activity decreased significantly in kidney, liver, gill, spleen and brain. However, after removing 2.0 mg/L copper exposure, ACP and ALP activities in different organs/tissues all normalized within 12 days. The observed data suggest that ACP and ALP in spleen of Carassius auratus gibelio var are most sensitive to copper stress and might be used as suitable biomarkers for copper contamination in aquatic environment

Sensors Anomaly Detection of Industrial Internet of Things Based on Isolated Forest Algorithm and Data Compression

Aiming at solving network delay caused by large chunks of data in industrial Internet of Things, a data compression algorithm based on edge computing is creatively put forward in this paper. The data collected by sensors need to be handled in advance and are then processed by different single packet quantity K and error threshold e for multiple groups of comparative experiments, which greatly reduces the amount of data transmission under the premise of ensuring the instantaneity and effectiveness of data. On the basis of compression processing, an outlier detection algorithm based on isolated forest is proposed, which can accurately identify the anomaly caused by gradual change and sudden change and control and adjust the action of equipment, in order to meet the control requirement. As is shown by experimental simulation, the isolated forest algorithm based on partition outperforms box graph and K-means clustering algorithm based on distance in anomaly detection, which verifies the feasibility and advantages of the former in data compression and detection accuracy

Genome-wide identification and expression analysis of calcium-dependent protein kinase in maize

BACKGROUND: Calcium-dependent protein kinases (CDPKs) have been shown to play important roles in various physiological processes, including plant growth and development, abiotic and biotic stress responses and plant hormone signaling in plants. RESULTS: In this study, we performed a bioinformatics analysis of the entire maize genome and identified 40 CDPK genes. Phylogenetic analysis indicated that 40 ZmCPKs can be divided into four groups. Most maize CDPK genes exhibited different expression levels in different tissues and developmental stages. Twelve CDPK genes were selected to respond to various stimuli, including salt, drought and cold, as well as ABA and H(2)O(2). Expression analyses suggested that maize CDPK genes are important components of maize development and multiple transduction pathways. CONCLUSION: Here, we present a genome-wide analysis of the CDPK gene family in maize for the first time, and this genomic analysis of maize CDPK genes provides the first step towards a functional study of this gene family in maize

Mesoporous silica nanoparticles enhance seedling growth and photosynthesis in wheat and lupin

The application of mesoporous silica nanoparticles (MSNs) as a smart delivery system to agricultural crops is gaining attention but the release of nanoparticles into the environment may pose a potential threat to biological systems. We investigated the effects of MSNs on the growth and development of wheat and lupin plants grown under controlled conditions. We report a dramatic increase in the growth of wheat and lupin plants exposed to MSNs. We also found that, in leaves, MSNs localised to chloroplasts and that photosynthetic activity was significantly increased. In addition, absorption and cellular distribution of MSNs by the two plant species following root uptake were observed using scanning electron microscopy equipped with energy dispersive spectroscopy (SEM-EDS). Following uptake of MSNs at 500 and 1000 mg L(-1), there was enhancement of seed germination, increased plant biomass, total protein and chlorophyll content. Treatment of both species with MSNs at the highest concentration (2000 mg L(-1)) did not result in oxidative stress or cell membrane damage. These findings show that MSNs can be used as novel delivery systems in plants and that over the range of concentrations tested, MSNs do not have any negative impacts on plant growth or development