Flow boiling in microchannels is one of the promising techniques for heat dissipation occurred in micro devices. However, the rapid bubble growth must be suppressed, which leads to serious boiling ...instabilities, high pressure drop, and low heat transfer coefficient. The addition of porous hydrophobic membrane has proven an effective method to remove the vapor in-site in the literature. However, the effects of heat sink’s topological structures on the vapor venting are still a research gap. The present study experimentally investigates the influence of Polytetrafluoroethylene (PTFE) membrane on fluid flow pattern, pressure drop, vapor venting performance, and heat transfer characteristics of flow boiling in the continuous and segmented heat sinks. Results show that the vapor venting membrane can reduce the pressure drop and increase the heat transfer coefficient effectively by decreasing the exit vapor quality, especially in combination with the segmented structures. The interconnection area as a space for bubble growth and coalescence is beneficial for vapor venting due to increased vapor pressure and quantity. Following the enhanced vapor discharge, the fluctuation of pressure drop is further weakened, which is conducive for the safe operation of heat sink.
Bubble condensation with non-condensable gas is more common than pure steam bubble. In this study, a systematic experimental investigation on the air-steam bubble condensation with comparatively ...large ranges of the liquid subcooling from 10 K to 70 K and different initial mole fractions of non-condensable gas <0.3 are carried out.
Results show that the air-steam bubble trends to condense as a whole when the initial mole fraction of non-condensable gas x0 is >15%. When x0 is <15%, the pattern transition from bubble shrink to split can be observed and the values of x0 corresponding to this transition trend to increase with the increasing liquid subcooling. A similar phenomenon can also be found in the pattern transition from bubble split to collapse. Meanwhile, three typical bubble breakage processes are observed and identified, which are named as flatten-, stretch- and shrink-breakage. Moreover, a new Nusselt number correlation is proposed which is related to bubble Reynolds number, Prandtl number, Jacob number and x0. After comparison, our correlation can predict well not only the results in this study but also the data-sets of air-steam bubble condensation given in the literature, which shows good performance in robustness.
•A systematic experiment on air-steam bubble direct contact condensation is proposed.•Three typical bubble breakage processes are firstly observed and identified.•A regime map on the bubble deformation in the condensation process is presented.•A new correlation of Nusselt number is given with a larger range of subcooling.•Our correlation can predict well the data of this study and those in the literature.
Grain size is an important agronomic trait determining rice yield and is mainly restricted by spikelet hull size. However, it remains largely unknown how the spikelet hull size is regulated. In this ...study, OsFH15, a class I formin protein in Oryza sativa, was found to be able to regulate the size of cells and spikelet hull. OsFH15-Cas9 and OsFH15-RNAi mutants had decreased grain size with reduced cell length, cell width and cell area of inner epidermal cells of the lemma compared with wild-type plants. By contrast, OsFH15-overexpressed plants had increased grain size with larger cells, as well as more abundant microtubules (MTs) and actin filaments (AFs) arrays. OsFH15 was mainly expressed in shoot apical meristem (SAM), spikelets, spikelet hulls and seeds in rice. In vitro biochemical experiments showed that OsFH15 can efficiently nucleate actin polymerization with or without profilin, can cap the barbed end of AFs, and can bind and bundle both AFs and MTs. OsFH15 can also crosslink AFs with MTs, and preferentially bind MTs to AFs. These results demonstrated that OsFH15 played an important role in grain-size control by affecting cell expansion through regulating AFs and MTs.
In many developing countries, organic agriculture is increasingly recognized as a key strategy for promoting rural economic development and improving farmer welfare. It is primarily smallholders who ...form the foundation of organic production in these areas. However, these farmers face significant challenges in adopting organic farming methods. The aim of this paper is to investigate solutions to the challenges encountered by smallholders. This research utilizes an integrated approach and includes a case study of the organic sorghum sector in Zunyi, China. The findings indicate that (1) a robust partnership has been established between enterprises, government, and farmers in the organic sorghum industry in Zunyi. Enterprises purchase the sorghum, cover organic certification costs, and partially fund material inputs, while local government facilitates organization, coordination, and technical support, with farmers responsible for production. (2) This collaboration has catalyzed high-quality development in the industry, benefiting all stakeholders. (3) Through this collaborative model, common challenges faced by smallholders, such as obstacles in obtaining certification, income fluctuations, and unfair market conditions, have been mitigated. Consequently, smallholders secure stable and reliable income as they benefit from favorable contract prices for organic sorghum and the assumption by enterprises of most material input costs. This study offers valuable empirical evidence that can guide the expansion of organic agriculture in similar regions and countries.
Based on the classic IPCC carbon emission calculation theory, this paper calculates the agricultural carbon emissions intensity and efficiency in Zhejiang Province from 2011 to 2020. The LMDI model ...is further adapted to carry out the influence factors of agricultural carbon emissions. In addition, the grey prediction model GM (1, 1) is used to predict the carbon emissions of Zhejiang Province from 2022 to 2025. The results show that the agricultural carbon emissions and carbon emission intensity in Zhejiang Province have a downward trend. Further, it is concluded that Shaoxing, Hangzhou, Jiaxing, and Huzhou are the cities with low emission and high efficiency, and Wenzhou is the city with high emission and low efficiency. Meanwhile, the improvement of Total Factor Productivity (TFP) results from the joint action of Technical Progress Efficiency (TECH) and Technical Efficiency (EFF). TECH is greater than EFF, and Scale Efficiency (SE) and Pure Technical Efficiency (PTE) contributions change with the years. In general, the contribution of PTE is more significant than that of SE, and its improvement mainly rests on technical progress. Among the factors influencing agricultural carbon emission efficiency, agricultural carbon emission intensity and labor force size have inhibiting effects on agricultural carbon emission efficiency growth. In contrast, agricultural industrial structure, economic development, and urbanization positively affect agricultural carbon emission efficiency. The prediction results show that the overall carbon emissions of Zhejiang Province will get a downward trend. Finally, based on these findings, we offer policy implications.
Reasonable distribution of profit from collaborative logistics transportation is the key to a smooth transition to a collaborative logistics system. This paper proposes a profit distribution model ...based on the use of an agent to solve issues related to equitable distribution of profit from collaborative logistics transportation. With this model, the logistics business is divided into active and passive collaborative business. The quotation process is then studied by introducing deadline and quotation parameters, and a quote or anti-quote program is put forward based on exploration of other logistics business issues, ultimately ensuring the satisfaction of all parties. Finally, the paper uses a model to demonstrate the efficiency of the collaboration, using comparative analysis, and the model is improved with the introduction of a new strategy for collaborative logistics profit distribution using a Rubinstein bargaining solution.
RabA4 subfamily proteins, the key regulators of intracellular transport, are vital for tip growth of plant polar cells, but their unique distribution in the apical zone and role in vesicle targeting ...and trafficking in the tips remain poorly understood. Here, we found that loss of Arabidopsis (
) AMINOPHOSPHOLIPID ATPASE 3 (ALA3) function resulted in a marked decrease in YFP-RabA4b/ RFP-RabA4d- and FM4-64-labeled vesicles from the inverted-cone zone of the pollen tube tip, misdistribution of certain intramembrane compartment markers, and an obvious increase in pollen tube width. Additionally, we revealed that phosphatidylserine (PS) was abundant in the inverted-cone zone of the apical pollen tube in wild-type Arabidopsis and was mainly colocalized with the trans-Golgi network/early endosome, certain post-Golgi compartments, and the plasma membrane. Loss of ALA3 function resulted in loss of polar localization of apical PS and significantly decreased PS distribution, suggesting that ALA3 is a key regulator for establishing and maintaining the polar localization of apical PS in pollen tubes. We further demonstrated that certain Rab GTPases colocalized with PS in vivo and bound to PS in vitro. Moreover, ALA3 and RabA4d collectively regulated pollen tube growth genetically. Thus, we propose that the tip-localized PS established by ALA3 is crucial for Rab GTPase-mediated vesicle targeting/trafficking and polar growth of pollen tubes in Arabidopsis.
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•Inorganic basalt fiber was modified with CPAM as carrier media.•Huge amount of biomass was harvested on the modified BF surface.•The extended DLVO theory was introduced to interpret ...the initial adhesion behavior.•Contributions of different interaction energy to bacteria adhesion was quantified.
Surface properties of carrier are critical for microorganism initial adhesion and biofilm formation in wastewater treatment. Until now, there are few reports on adhesion behaviors between bacteria and inorganic fiber surface. In this study, inorganic basalt fiber (BF) was modified with cationic polyacrylamide (CPAM) to make surface more hydrophilic and positively charged. The initial adhesion behaviors of BF modified with CPAM (CMBF) were interpreted by thermodynamics and extended Derjaguin–Landau–Verwey–Overbeek (DLVO) theory. According to the total interaction energy calculated by the extended DLVO theory, insurmountable energy barrier between BF and Escherichia coli (E. coli) made irreversible adhesion unachievable due to hydrophobicity and electronegativity of BF, but allowed reversible adhesion at second minimum. By contrast, the energy barrier between CMBF and E. coli could be overcome allowing irreversible bacterial adhesion and thus a huge amount of biomass because of hydrophilicity and electropositivity of CMBF. The results showed the total interaction energies were dominated by Lewis acid-base and electrostatic interactions and coating BF with CPAM could promote initial bacterial adhesion on carrier surface. Overall, the extended DLVO theory provides a comprehensive tool to interpret initial adhesion behaviors between bacteria and inorganic fibers.
Rainbow trout (Oncorhynchus mykiss) is one of the world's most widely farmed cold-water fish. However, the rise in water temperature caused by global warming has seriously restricted the development ...of rainbow trout aquaculture. In this study, we investigated the physiological responses in the liver of rainbow trout exposed to 20 ℃ and 24 ℃ and returning to the initial temperature (14 ℃) by combining biochemical analyses and UPLC-QTOF-MS metabolomics. The results of the biochemical analysis showed that serum aminotransferase, lysozyme, total bilirubin, alkaline phosphatase and liver superoxide dismutase, glutathione peroxidase, and malondialdehyde in rainbow trout under heat stress changed significantly. Even after the temperature recovery, some of the above indicators were still affected. Compared to the control group, 115, 130, and 121 differentially expressed metabolites were identified in the 20 ℃, 24 ℃, and recovery groups, respectively. Further pathway enrichment of these metabolites revealed that heat stress mainly affected the linoleic acid metabolism, α-linolenic acid metabolism, glycerophospholipid metabolism, and sphingolipid metabolism in the liver of rainbow trout, and continuously affected these metabolic pathways during the recovery period. Notably, the enrichment of glutathione metabolic pathways was consistent with the changes in glutathione peroxidase in the biochemical results. The results above suggest that heat stress can induce immune responses and oxidative stress inside the rainbow trout. After temperature recovery, some of the hepatic functions of fish return to normal gradually. The biochemical analysis and UPLC-QTOF-MS metabolomics tools provide insight into the physiological regulation of rainbow trout in response to heat stress.
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•Heat stress induced protective responses in the antioxidant system and immune response of rainbow trout.•Phospholipid and polyunsaturated fatty acid metabolism in liver of rainbow trout modified by high temperature.•The activation of glutathione metabolism agreed with increased glutathione peroxidase activity.
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