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Biomass is a promising alternative energy source for fossil fuel with the advantages of abundance, renewability, environmental friendliness, etc. This makes the development of biomass technology be of great potential and interesting. The experiments of biomass fast pyrolysis were performed in a microquartz reactor for rice husk (RH), corn stalk (CS) and birch wood (BW), and scanning electron microscope (SEM), energy dispersive spectrometer, and Raman microscope were then applied to analyze the collected chars. The average char yields of RH, CS, and BW pyrolyzed at 800 °C were 29.64%, 18.67%, and 8.64%, respectively. The morphological structures of RH and CS were mainly reserved in chars, while the raw surface textures of BW disappeared during the fast pyrolysis. The silicon concentrations in RH char and CS char were much higher than BW char, and the graphitization degree of CS char was the lowest among the three biomass chars.

The leafy seadragon certainly is among evolution's most "beautiful and wonderful" species aptly named for its extraordinary camouflage mimicking its coastal seaweed habitat. However, limited information is known about the genetic basis of its phenotypes and conspicuous camouflage. Here, we revealed genomic signatures of rapid evolution and positive selection in core genes related to its camouflage, which allowed us to predict population dynamics for this species. Comparative genomic analysis revealed that seadragons have the smallest olfactory repertoires among all ray-finned fishes, suggesting adaptations to the highly specialized habitat. Other positively selected and rapidly evolving genes that serve in bone development and coloration are highly expressed in the leaf-like appendages, supporting a recent adaptive shift in camouflage appendage formation. Knock-out of bmp6 results in dysplastic intermuscular bones with a significantly reduced number in zebrafish, implying its important function in bone formation. Global climate change-induced loss of seagrass beds now severely threatens the continued existence of this enigmatic species. The leafy seadragon has a historically small population size likely due to its specific habitat requirements that further exacerbate its vulnerability to climate change. Therefore, taking climate change-induced range shifts into account while developing future protection strategies.

Response of aquatic organisms to eutrophication have been well reported, while less studies are available for the recovery of eutrophic lakes following a reduction in the external loading, especially for systems where nitrogen is reduced but the phosphorus concentration is maintained high due to internal loading. Diatoms are nitrate (NO3-N) opportunists but can also use ammonium (NH4-N). They may, therefore, be more sensitive to nitrogen reduction than other algae that typically prefer NH4-N. We document the variations of nutrients and diatoms in subtropical, eutrophic Lake Taihu over 28 yr during which a reduction of the external loading resulted from lake management. According to the results of change point analysis, data on environmental variables were divided into two periods (P1: 1992-2006; P2: 2007-2019) with two different seasons (WS: Winter-Spring; SA: Summer-Autumn), respectively. Compared with P1-WS, the concentration of NH4-N decreased significantly whereas NO3-N showed no significant change in P2-WS. In contrast, NH4-N concentrations were low and showed no significant changes in P1-SA and P2-SA and NO3-N decreased significantly in the latter period. Accordingly, NO3-N: NH4-N mass ratios in P1-SA and P2-WS were all significantly higher than those in P2-SA and P1-WS, respectively. The biomass of WS diatom increased significantly and the timing of the peak biomass shifted from P1-SA to P2-WS since 2007. The SEM analysis showed that NO3-N was retained as a statistically significant predictor for diatom biomass in P1-SA and significant effects of windspeed, zooplankton and NH4-N on diatom biomass in P2-WS. Windspeed and zooplankton have further changed the biomass of diatoms in the case of declining inorganic nitrogen. We conclude that the magnitude of vernal suppression or stimulation of diatom assemblages has increased, concomitant with the variations of NH4-N and NO3-N: NH4-N mass ratios. Diatoms response to NH4-N or NO3-N is apparently changing in response to water temperature in this eutrophic shallow lake. Thus, parallel reductions in external nitrogen loading, along with variations in dominant inorganic nitrogen, will stimulate the growth of diatom and therefore increase the total biomass of phytoplankton in still high internal phosphorus loading, which is should be regarded as a good sign of restoration measures.

Robust mitigation options will play significant role in achieving the target of limiting global change to below 1.5 °C above pre-industrial levels by 2100. To support cooperation for mitigation development, we establish a real options-based model to evaluate the rational decisions of exercising the abandon option for carbon capture and storage-enhanced oil recovery (CCS-EOR) projects under oil market and geological uncertainties. Three possible cooperative mechanisms (fixed carbon dioxide (CO2) price, oil-indexed CO2 price, and joint venture contracts) among CO2-EOR stakeholders are evaluated. The results show that the conflicts in profit maximization targets for different stakeholders in cooperative mitigation are to a great extent unable to be avoided. A joint venture business model is preferred in cooperative mitigation as it can effectively weaken such conflicts. And it is more reasonable to provide incentives to the downstream of the CO2-EOR chain than compensating the adoption cost of carbon capture technologies in the upstream. From a global perspective, the inefficient cooperation can be a main barrier that hinders the development of deep-cutting options. Global mitigation strategies should not only focus on promoting technology progress but also the design of innovative business models to balance the benefits among stakeholders. A joint venture business model is recommended in both the developed and developing countries for seizing the early mitigation opportunities.

Root–soil mechanical interactions are of vital importance in soil reinforcement by plant roots. However, it is unclear how the angles of the roots in the soil affect the root–soil mechanical interactions. To better understand the effect of this factor on root–soil mechanical interactions, pullout tests were conducted on alfalfa (Medicago sativa L.) roots with five root diameter groups (0.10–0.30 mm, 0.31–0.50 mm, 0.51–0.70 mm, 0.71–0.90 mm and 0.91–1.10 mm) and four embedding angles (30°, 45°, 60° and 90°) in sandy loam soil. Root tensile tests were also carried out to understand the process of root failure in the pullout tests. The results showed that the roots had two failure modes, slippage failure and breakage failure. The critical diameter of the two failure modes was 0.35 mm. Peak pullout force and pullout energy were positively related to the root diameter in power functions. Displacement was negatively related to the root diameter and embedding angle in exponential functions. Peak pullout force, root–soil friction coefficient and pullout energy all increased and then decreased with increasing embedding angles. The peak pullout force and root–soil friction coefficient reached their maximum values under an embedding angle of 60°, and pullout energy reached the maximum value under an embedding angle of 45°. Pullout energy was suggested as a preferred index of root–soil mechanical interactions for both thick/fine roots and inclined/upright roots.

Abstract Liquid fuels are likely to remain the main energy source in long-range transportation and aviation for several decades. To reduce our dependence on fossil fuels, liquid biofuels can be blended to fossil fuels – or used purely. In this paper, coconut methyl ester, standard diesel fuel (EN590:2017), and their blends were investigated in 25 V/V% steps. A novel turbulent combustion chamber was developed to facilitate combustion in a large volume that leads to ultra-low emissions. The combustion power of the swirl burner was 13.3 kW, and the air-to-fuel equivalence ratio was 1.25. Two parameters, combustion air preheating temperature and atomizing air pressure were adjusted in the range of 150–350 °C and 0.3–0.9 bar, respectively. Both straight and lifted flames were observed. The closed, atmospheric combustion chamber resulted in CO emission below 10 ppm in the majority of the cases. NO emission varied between 60 and 183 ppm at straight flame cases and decreased below 20 ppm when the flame was lifted since the combustion occurred in a large volume. This operation mode fulfills the 2015/2193/EU directive for gas combustion by 25%, which is twice as strict as liquid fuel combustion regulations. The 90% NO emission reduction was also concluded when compared to a lean premixed prevaporized burner under similar conditions. This favorable operation mode was named as Mixture Temperature-Controlled (MTC) Combustion. The chemiluminescent emission of lifted flames was also low, however, the OH* emission of straight flames was clearly observable and followed the trends of NO emission. The MTC mode may lead to significantly decreased pollutant emission of steady-operating devices like boilers, furnaces, and both aviation and industrial gas turbines, meaning an outstanding contribution to more environmentally friendly technologies.

Coal fire is a global catastrophe. Xinjiang suffers the most severe coal fire in China and even in the world. Coal firefighting work has been being conducted for decades in Xinjiang. In this paper, coal fire detection, extinguishing, and monitoring approaches that were derived from coal firefighting experience are introduced in detail by taking the Fifth Fire Area (FFA) of the Heshituoluogai coal fire for instance. We first introduce the geology and fire situation in the FFA. Before developing efficient strategies to extinguish it, magnetic and self-potential methods are adopted to delineate the extent of the fire. A composite index is proposed to better indicate the fire. The comprehensive coal firefighting method is illustrated in detail, which consists of surface cooling, excavation and leveling, borehole drilling, borehole water injection and grouting, and loess backfill. The subsequent temperature and CO monitoring records show that the fire is extinguished successfully without burnback. The methodology presented here provides guidance and reference for putting out other coal fires around the world.

AbstractSolubilities of CO2, CH4, H2, CO and N2 in choline chloride/urea (ChCl/Urea) were investigated at temperatures ranging from 308.2 to 328.2 K and pressures ranging from 0.6 to 4.6 MPa. The results show that the solubilities of gases increase with increasing pressure and decreasing temperature. The solubility of CO2 is higher than that of CH4, H2, CO and N2, which indicates that ChCl/Urea may be used as a potential solvent for CO2 capture from the gas mixture. Solubility of CO2 in ChCl/Urea was fitted by Non-Random Two-Liquid and Redlich–Kwong (NRTL-RK) model, and solubility of CH4, H2, CO or N2 in ChCl/Urea was fitted by Henry's Law. The standard enthalpy, standard Gibbs energy and standard entropy of gases were calculated. Additionally, the CO2/CH4 selectivities in water, dry ChCl/Urea and aqueous ChCl/Urea were further discussed.