The double-scroll wrap can effectively increase the volume flow rate compared with the commonly used single-scroll structure, but its built-in volume ratio is extensively reduced. With the aim of ...improving its built-in volume ratio, this study presented a fully meshed double-scroll profile, or called modified double-scroll, and proposed a generation method for it; its profile equations as well as relationships between its geometric parameters were obtained, and effects of the geometric parameters on the compressor performance were analyzed. Moreover, thermodynamic characteristic and working process of the double-scroll compressor were numerically simulated and verified with its performance experiment. It is found that the proposed fully meshed double-scroll significantly increases the built-in volume ratio by 33.8 %; meanwhile, it increases the volume flow rate, reduces the friction velocity between the orbiting and fixed scrolls, and decreases scroll dimensions. The proposed fully meshed double-scroll can be applied to the design and manufacture of scroll compressors.
The claw vacuum pump is extensively utilized in semiconductor, photovoltaic and aerospace industries because of its dry oil-free and compact structure. In order to reduce the power consumption of the ...claw vacuum pump caused by its special mixing process during operation, a novel pair of claw rotors was proposed. This innovation involves replacing the conventional circular arc at the dedendum of the claw rotors with an eccentric circular arc. A geometric model of the novel claw rotor was established, and the geometric characteristics of both the novel and conventional claw rotors were compared. Subsequently, the optimal design parameters were determined. The pressure distribution and power consumption of two claw vacuum pumps were analyzed with numerical simulations. Study results indicates that the power consumption of the proposed claw vacuum pump in the mixing process is reduced by 72.3 %, and the total power consumption is reduced by 12.6 % compared to the conventional pump. The study is of great significance for reducing power consumption of the claw vacuum pumps and improving application.
•An optimal design method of claw rotor profiles was proposed.•Change law of pressure for the novel vacuum pump during operation was obtained.•Internal flow fields of the novel vacuum pump were simulated.•Power consumption of the novel claw vacuum pump was remarkably reduced.
Abstract Owing to the structure of the gear-claw rotor, working chambers of claw pumps are divided into small multi-chambers by a pair of intermeshing claw rotors in the mixing process, and the ...transient flow in multi-chambers is complicated, which results in the increase of the pump consumption. Hence, it is necessary to study the transient flow and working process of gear-claw hydrogen circulating pumps to optimize the pump performance. In this study, the meshing model of a high-order curve and its conjugate curve was proposed, and the profile composition of the gear-claw rotor was introduced. The influence of the radius ratio of claw addendum arc on the performance including relative carryover, built-in volume ratio and volume utilization was analyzed. The flow field of gear-claw hydrogen circulating pump including pressure and velocity field was analyzed by using numerical simulations. Furthermore, the p - V diagram of pumps was obtained. It is found that the gas in the compression chamber is mixed with the gas in the carryover, and the initial pressure in the compression chamber is 130.78kPa, which increases by 29.07% compared to the original initial pressure in the compression chamber. Therefore, an overcompression phenomenon at the end of the compression process (at the beginning of the discharge process) occurs.
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•SMF enhanced AGS salt-tolerance to improve nitrogen removal of saline wastewater.•SMF shortened granulation by promoting EPS secretion with high protein contents.•Obvious sludge ...bulking occurred at 2.0% salinity without SMF.•Better SPND performance was in SMF with TN removal recovering to 72.9% finally.•SMF improved the activity of predominant halotolerant genus.
Saline wastewater poses a threat to biological nitrogen removal. This study investigated whether and how static magnetic field (SMF) can improve the salt-tolerance of aerobic granular sludge (AGS) in two simultaneous partial nitrification and denitrification (SPND) reactors. Results confirmed that the SMF improved the mean size and settleability of granules, stimulated secretion of extracellular polymeric substances with high protein content, in turn enhancing the aerobic granulation. Although high salt stress inhibited functional microorganisms, the SMF maintained better SPND performance with average COD removal, TN removal and nitrite accumulation ratio finally recovering to 100%, 72.9% and 91.1% respectively. High throughput sequencing revealed that functional bacteria evolved from Paracoccus to halotolerant genera Xanthomarina, Thauera, Pseudofulvimonas and Azoarcus with stepwise increasing salinity. The enhanced salt-tolerance may be because the SMF promoted the activity of these halotolerant bacteria. Therefore, this study proposes an economic, effective and environmental biotechnology for saline wastewater treatment.
Soil microorganisms play important roles in crop production and sustainable agricultural management. However, soil conditions and crop selection are key determining factors for soil microbial ...communities. This study investigated the effect of plant types and soil salinity on the microbial community of interspecific interaction zone (II) based on the sorghum/peanut intercropping system. Microbial community diversity and composition were determined through PacBio single molecule, real-time sequencing of 16S rDNA and internal transcribed spacer (ITS) genes. Results showed Proteobacteria, Bacteroidota, and Acidobacteriota to be the dominant bacterial phyla in IP, II, and IS, whereas Ascomycota, Basidiomycota, and Mucoromycota were the dominant fungal phyla. Under salt-treated soil conditions, the plants-specific response altered the composition of the microbial community (diversity and abundance). Additionally, the interspecific interactions were also helpful for maintaining the stability and ecological functions of microbial communities by restructuring the otherwise stable core microbiome. The phylogenetic structure of the bacterial community was greatly similar between IP and II while that of the fungal community was greatly similar between IP and IS; however, the phylogenetic distance between IP and IS increased remarkably upon salinity stress. Overall, salinity was a dominant factor shaping the microbial community structure, although plants could also shape the rhizosphere microenvironment by host specificity when subjected to environmental stresses. In particular, peanut still exerted a greater influence on the microbial community of the interaction zone than sorghum.
The peanut is one of the most important oil crops worldwide. Qualities and yields of peanut can be dramatically diminished by abiotic stresses particularly by drought. Therefore, it would be ...beneficial to gain a comprehensive understanding on peanut drought-responsive transcriptional regulatory activities, and hopefully to extract critical drought-tolerance-related molecular mechanism from it.
In this study, two peanut Arachis hypogaea L. varieties, NH5 (tolerant) and FH18 (sensitive), which show significantly differential drought tolerance, were screened from 23 main commercial peanut cultivars and used for physiological characterization and transcriptomic analysis. NH5 leaves showed higher water and GSH contents, faster stomatal closure, and lower relative conductivity (REC) than FH18. Under the time-course of drought-treatments 0 h (CK), 4 h (DT1), 8 h (DT2) and 24 h (DT3), the number of down-regulated differential expressed genes (DEGs) increased with the progression of treatments indicating repressive impacts on transcriptomes by drought in both peanut varieties.
Nevertheless, NH5 maintained more stable transcriptomic dynamics than FH18. Furthermore, annotations of identified DEGs implicate signal transduction, the elimination of reactive oxygen species, and the maintenance of cell osmotic potential which are key drought-tolerance-related pathways. Finally, evidences from the examination of ABA and SA components suggested that the fast stomatal closure in NH5 was likely mediated through SA rather than ABA signaling. In all, these results have provided us a comprehensive overview of peanut drought-responsive transcriptomic changes, which could serve as solid foundation for further identification of the molecular drought-tolerance mechanism in peanut and other oil crops.
Early sowing has been extensively used in high-latitude areas to avoid drought stress during sowing; however, cold damage has become the key limiting factor of early sowing. To relieve cold stress, ...plants develop a series of physiological and biochemical changes and sophisticated molecular regulatory mechanisms. The biomembrane is the barrier that protects cells from injury as well as the primary place for sensing cold signals. Chilling tolerance is closely related to the composition, structure, and metabolic process of membrane lipids. This review focuses on membrane lipid metabolism and its molecular mechanism, as well as lipid signal transduction in peanut (
) under cold stress to build a foundation for explicating lipid metabolism regulation patterns and physiological and molecular response mechanisms during cold stress and to promote the genetic improvement of peanut cold tolerance.
Nitrogen (N) is a crucial element for increasing photosynthesis and crop yields. The study aims to evaluate the photosynthetic regulation and yield formation mechanisms of different nodulating peanut ...varieties with N fertilizer application.BACKGROUNDNitrogen (N) is a crucial element for increasing photosynthesis and crop yields. The study aims to evaluate the photosynthetic regulation and yield formation mechanisms of different nodulating peanut varieties with N fertilizer application.The present work explored the effect of N fertilizer application rates (N0, N45, N105, and N165) on the photosynthetic characteristics, chlorophyll fluorescence characteristics, dry matter, N accumulation, and yield of four peanut varieties.METHODThe present work explored the effect of N fertilizer application rates (N0, N45, N105, and N165) on the photosynthetic characteristics, chlorophyll fluorescence characteristics, dry matter, N accumulation, and yield of four peanut varieties.The results showed that N application increased the photosynthetic capacity, dry matter, N accumulation, and yield of peanuts. The measurement of chlorophyll a fluorescence revealed that the K-phase, J-phase, and I-phase from the OJIP curve decreased under N105 treatment compared with N0, and WOI, ET0/CSM, RE0/CSM, ET0/RC, RE0/RC, φPo, φEo, φRo, and Ψ0 increased, whereas VJ, VI, WK, ABS/RC, TR0/RC, DI0/RC, and φDo decreased. Meanwhile, the photosystem activity and electron transfer efficiency of nodulating peanut varieties decreased with an increase in N (N165). However, the photosynthetic capacity and yield of the non-nodulating peanut variety, which highly depended on N fertilizer, increased with an increase in N.RESULTSThe results showed that N application increased the photosynthetic capacity, dry matter, N accumulation, and yield of peanuts. The measurement of chlorophyll a fluorescence revealed that the K-phase, J-phase, and I-phase from the OJIP curve decreased under N105 treatment compared with N0, and WOI, ET0/CSM, RE0/CSM, ET0/RC, RE0/RC, φPo, φEo, φRo, and Ψ0 increased, whereas VJ, VI, WK, ABS/RC, TR0/RC, DI0/RC, and φDo decreased. Meanwhile, the photosystem activity and electron transfer efficiency of nodulating peanut varieties decreased with an increase in N (N165). However, the photosynthetic capacity and yield of the non-nodulating peanut variety, which highly depended on N fertilizer, increased with an increase in N.Optimized N application (N105) increased the activity of the photosystem II (PSII) reaction center, improved the electron and energy transfer performance in the photosynthetic electron transport chain, and reduced the energy dissipation of leaves in nodulating peanut varieties, which is conducive to improving the yield. Nevertheless, high N (N165) had a positive effect on the photosystem and yield of non-nodulating peanut. The results provide highly valuable guidance for optimizing peanut N management and cultivation measures.CONCLUSIONOptimized N application (N105) increased the activity of the photosystem II (PSII) reaction center, improved the electron and energy transfer performance in the photosynthetic electron transport chain, and reduced the energy dissipation of leaves in nodulating peanut varieties, which is conducive to improving the yield. Nevertheless, high N (N165) had a positive effect on the photosystem and yield of non-nodulating peanut. The results provide highly valuable guidance for optimizing peanut N management and cultivation measures.
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