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Silicon carbide fiber-reinforced silicon carbide ceramic matrix composites（SiCf/SiC） used in aero-engines are damaged or even failed due to the oxidation and corrosion by high-temperature and high-speed combustion gases. In this work，the gas generation device was used to simulate the complex gas environment in the aircraft engine，and the aviation kerosene mixed with liquid oxygen fuel in a certain proportion was ignited to form a high-temperature and high-speed combustion gas to assess the material. The oxidation test for 10 h and thermal shock test for 1000 cycles in combustion gas environment at 1200 ℃ were conducted on SiCf/SiC composites respectively. And the protective effect of environmental barrier coating（EBC）on SiCf/SiC composites was investigated. Uniaxial tensile tests were conducted on SiCf/SiC composites and SiCf/SiC-EBC composites after combustion gas environment assessment，and their fracture and cross-section micro-morphologies were observed by scanning electron microscopy. The results show that no significant oxidation of fibers and interphases is found in SiCf/SiC composites and SiCf/SiC-EBC composites after oxidation for 10 h in combustion gas environment，and their uniaxial tensile strength decreases by less than 2%. After 1000 thermal shock cycles in combustion gas environment，multiple micro-cracks are formed and oxidative corrosion of the interfacial layer occurs inside the SiCf/SiC composites，and the uniaxial tensile strength decreases by 41.3%. The EBC coating can effectively protect the SiCf/SiC composites from oxidation and corrosion of high-temperature gas，and the uniaxial tensile strength of SiCf/SiC-EBC composites decreases by 16.6% after 1000 thermal shock cycles.

The dovetail of ceramic matrix composites（CMC）turbine blade is the key to the assembly and ability to withstand centrifugal loads of the blade. In order to study the mechanical behaviour of the blade dovetail prepared by the melt infiltration（MI）method under the tensile load in the radial direction of rotating，and verify the influence of the internal quality of the dovetail on its static tensile strength and failure mode，the CMC high pressure turbine dovetail element specimens were designed and fabricated，and a uniaxial static tensile test was conducted，the internal quality of the test specimens was scanned using non-destructive X-ray CT. The test process was monitored using DIC and acoustic emission method. The results show that the CMC dovetail is able to maintain in complete contact under uniaxial static tensile loads，and its static strength and failure are very sensitive to its internal quality，especially to the delamination defects. When there are no delamination defects in the dovetail，the damage generally starts from the neck and quickly spreads，the damage starting load is near the maximum fracture load，and the fracture surface is zigzag. When there are delamination defects in the dovetail，the fracture starts from the defects，and the delamination gradually spread and cause the fracture surface of the dovetail，the damage starting load is decreased by 99.05%，and the maximum failure load is decreased by 14.29% compared to the case of no delamination defects，and the fracture surface is consistent with the delamination defects.

Water is necessary for all biological life and industrial, municipal, agricultural, and residential processes. It is challenging to imagine living without water. Unfortunately, human and natural activities are causing the sources of useable water to become contaminated. Despite having enormous and unique natural water resources, Africa has experienced unprecedented environmental pollution because of the abuse of these resources. Additionally, population increase and urbanization brought by technological advancements have significantly worsened water pollution in Africa. The significant causes of pollution for surface waterways are untreated effluents released into the environment by humans and machines. It is still being determined if the emission goals set by several African countries for surface water discharge have been fulfilled. Wells and boreholes are essential sources of drinking water for Africans. However, because of their location in sterile areas, the natural water quality of these groundwater sources could be better. The primary sources of water pollution in Africa include agricultural activities, mining, roadside discharges, trash from companies and workshops, landfills, and e-waste. Oil leaks are a severe problem in oil-rich African countries. Lake Tanganyika is East Africa's most significant freshwater reservoir, while Lake Victoria is the second-deepest lake in the world. HIGHLIGHTS Evaluate scientific findings on water quality in the lakes on the African continent.; Identify the principal contaminants of surface water.; Pearson Correlation is used to identify the relationship among the water parameters.;

Terahertz (THz) wave plays important roles in the research of material properties, the non-invasive human security check and the next generation wireless communication. The progress of the scientific and technological applications of THz wave is strongly dependent on the improvement of THz detectors. Here a novel THz wave detection scheme is proposed in which the THz radiation is detected by an audible microphone based on the photo-thermo-acoustic (PTA) effect in graphene foam. Thanks to the room-temperature broadband electromagnetic absorption characteristics of graphene foam and the fast heat transfer between graphene foam and ambient air, this detection method not only inherits the advantages of the photo-thermal THz detector such as room-temperature and full bandwidth, but also has a response time 3 orders of magnitude faster than the photo-thermal detector. Besides, no micro-antenna/electrode is required to fabricate in the graphene foam THz detector which greatly simplifies the detector design and decreases the fabrication cost. It concludes that the room-temperature, full-bandwidth, fast-speed (≥10 kHz), and easy-to-fabricate THz detector developed in this work has superior comprehensive performances among both the commercial THz detectors and the detectors recently developed in laboratory.

Flotation is an important method for the separation of fine materials.The type of frothers and the stability of the foam significantly affect flotation performance.In this paper, three foaming agents of alcohols (MIBC), esters (DEP) and ether alcohols (DGBE) are selected to investigate the effect of functional groups in frothers on foaming performance and foam stability.Foamscan was used in the experiment to determine the foaming performance and foam stability of the frothers, and the Tracker rheometer was used to determine surface tension and the viscoelastic modulus of the air-liquid interface.Results show that the foaming rate increases linearly with the decrease of surface tension.It reaches its peak/the maximum when the gas-liquid interface adsorbs the foaming agent to saturation, and when the adsorption of the foaming agent on the gas-liquid interface reaches saturation.The foaming rate of MIBC reaches its peak/the maximum and that of DGBE its trough/the minumum.When the concentration of the frother reaches the critical mass fraction, the foaming ability reaches its peak/the maximum, and the critical mass fractions of MIBC, DEP and DGBE are 1.1 %, 0.4 % and 0.8 %.The size of the bubbles decreases with the decrease of the surface tension of the solution, and the order of the average bubble size from large to small is: DGBE>DEP>MIBC.The ether alcohol frothers have the strongest foam stability, while the alcohol frothers have the worst foam stability.The foam is the most stable.when the mass fractions of MIBC, DEP and DGBE are 0.4 %, 0.5 % and 0.8 %.

Allergic rhinitis (AR) influenced over half billion people around the globe, and its mechanism had been studied for long. While the role of Th1 and Th2 in AR was supported by substantial evidence, the relationship between Th17, Tregs, and AR was less researched. The role of Th17 and Tregs was less understood and sometimes downplayed. However, Recent studies suggested a close relationship between Th17, Tregs, and AR. Th17 and Treg secreted cytokines that could promote or attenuate inflammation and other AR symptoms via interaction with other molecules, cells, and pathways. This essay summarized these studies, and might provide a more thorough insight on AR mechanism and potential AR treatments. Th17 enhanced AR through the release of proinflammatory cytokines, including IL-17 that induced other immune cell response through multiple pathways, increased IgE production via interaction with other interleukins and cells, and promoted the release of other pro-inflammatory mediators. Tregs inhibited inflammation of via the release of anti-inflammatory cytokines including IL-10 and TGF-β, which suppressed the response of other immune cells such as T cell, B cell, eosinophil, and mast cell, inhibited IgE function via regulated immune cell response, and decreased pro-inflammatory factor release through involvement in the STAT3 related pathway. Based on these studies, several potential AR treatments emerged, as anti-IL-17-neutralizing antibodies, anti-IL-33 antibodies, and CC10 effectively inhibited inflammation, and probiotic NVP-1703 reduced rhinorrhea, nasal congestion, watery eyes, and sleep disturbance, though further research was necessary in order to comprehensively examine and compare the efficacy of these treatments. Understanding the role of Th17 and Treg could help researchers develop new drug that target specific messenger in signalling transduction pathways of Th17 and Treg cytokines that might augment or attenuate AR symptoms or immune response, giving rise to a probability of AR treatments with less adverse effects and stronger efficacy in the future.

The acquisition and communication of ecological and environmental risk information can effectively mitigate the social risks caused by ecological and environmental damage in coal power base.According to the risk information seeking and processing model (RISP), a questionnaire survey was conducted on the social population around Xilinhaote coal power base.The acquisition and preference of ecological risk information during the development of coal-fired power bases was quantitatively analyzed.The results show the following four points: The probability of inadequate access to eco-environmental risk information of coal-fired power base is as high as 51.5 %.The Internet as a source of risk information is favored by 53.4 % of the public, and the probability of public expressing trust in eco-environmental risk information of various channels is as high as 50 %, and the probability of distrust in eco-environmental risk information with data is significantly reduced to 14.6 %.Herdsmen's adequacy and ability of risk information acquisition are relatively low, and the risk information acquisition channel is traditional and single.Improving residents' educational level can effectively improve the adequacy of information acquisition and enrich the access to risk information.Compared with protection policies, the respondents are in favor of eco-environmental protection measures, such as vegetation planting, enclosure, etc.which are carried out in a direct and effective way.It is suggested that that the mechanism of public participation targeted at the social groups be established, risk education through various channels be enhanced and long-term information communication mechanism be implemented during the whole process of the development in coal and electricity bases.

Cooling technology is widely applied in modern turbines to protect the turbine blades, and extracting high-pressure cooling air from a compressor exerts a remarkable influence on the gas-turbine performance. However, the three-dimensional optimal design of a turbine in modern industrial practice is usually carried out by pursuing high component efficiency without considering possible changes in coolant requirement; hence, it may not exactly lead to improvement in the gas-turbine cycle efficiency. In this study, the turbine stator was twisted and leaned to achieve higher comprehensive efficiency, which is the cycle-based efficiency definition for a cooled turbine that considers both turbine aerodynamic performance and coolant requirement. First, the influence of twist and compound lean on turbine aerodynamic performance, considering stator-hub leakage, was investigated. Then, a method to predict the coolant requirement for turbines with different stator designs was applied, to evaluate coolant-requirement change at the design condition. The optimized turbines were finally compared to demonstrate the necessity of considering the coolant-requirement change in the optimal design. This indicated that proper twisting to open the throat area in the stator hub and compound lean to the pressure surface side could help improve the cooled-turbine comprehensive efficiency.

Dianchi Lake is one of the key management points of China’s “three rivers and three lakes basins”, and the construction of wetland park plays an important role in purifying Dianchi lake water body and maintaining the health of lake ecosystem. Based on single factor evaluation method and three improved Nemerow pollution index methods, this study evaluates water quality of South Dianchi Wetland Park, Xihua Wetland Park and Laoyu River Wetland Park, with concentrations of total nitrogen (TN), total phosphorous (TP), chemical oxygen demand (COD), zinc (Zn), nickel (Ni), cadmium (Cd), chromium (Cr), lead (Pb) specifically measured and monitored. The results showed that: (1) the pollution levels of COD, TN, TP and Cr in the three wetland parks are relatively high. (2) based on single factor evaluation method and the improved Nemerow pollution index method, the evaluation grade of the water quality of the three wetland parks is inferior to Grade V. On the whole, the water pollution of Laoyu River Wetland Park is the most worrisome, and the water pollution of South Dianchi and Xihua Wetland Park is slightly better. (3) COD and TP are the main types of pollutants entering the lake in the basins where the three wetland parks are located. Therefore, immediate attention should be paid to the management of water quality state of Dianchi Lake, and the treatment of urban, agricultural non-point source and some uncollected point source pollution should be further strengthened.

Puzhehei Lake is located in Wenshan Prefecture, Yunnan Province. Water pollution assessment is of great significance for the pollution control of the lake and the sustainable development of the basin. This study evaluates the water pollution and eutrophication status of three sampling points (upstream, middle and downstream) of Puzhehei Lake based on single factor evaluation method, comprehensive pollution index method and improved comprehensive pollution index method based on entropy weight method, and analyzes the water health risk. The results show that the water quality of the three sampling points is sub-class V using the single factor evaluation method. The water quality evaluation result based on the traditional comprehensive pollution index method shows that the water quality of the three sampling points belongs to heavy pollution. By contrast, the improved comprehensive pollution index method based on entropy weight method shows that the water quality of Leshui Cave belongs to class V, while the water quality of Puzhehei Village and Karst Wetland Park belongs to class V. According to the comprehensive evaluation method, the water quality of the three sampling points before and after correction is ranked from good to bad as follows: Leshui Cave, Karst Wetland Park and Puzhehei Village. The water bodies of Leshui Cave and Puzhehei Village are moderately nutritious, and the water bodies of Karst Wetland Park are oligotrophic. The chemical carcinogens health risk in water at the three sampling points exceeded the standard seriously, and the risk ranking was as follows: Karst Wetland Park > Leshui Cave > Puzhehei Village, in which Cr exceeded the standard seriously. The non carcinogenic health risk are low, and the risk ranking is Puzhehei Village > Leshui Cave > Karst Wetland Park. In the future water quality control, we should focus on the strict control of TN and TP in rivers entering the lake.

We present the Manatee variational autoencoder model to predict transcription factor (TF) perturbation-induced transcriptomes. We demonstrate that the Manatee in silico perturbation analysis recapitulates target transcriptomic phenotypes in diverse cellular lineage transitions. We further propose the Manatee in silico screening analysis for prioritizing TF combinations targeting desired transcriptomic phenotypes.