•Energy transfer procession in an ASHP unit during defrosting was explored.•Effect of metal energy storage on defrosting was proposed and calculated.•Metal energy storage effect was changed from ...positive (0.33%) to negative (−2.18%).•Defrosting efficiency was improved about 6.08%, from 42.26% to 48.34%.•Contributions of this study can guide the design optimization of two ASHP’s coils.
Air source heat pump units have found their wide applications in recent decades due to their high efficiency and low environmental pollution. To solve their undesired frosting problem, reverse cycle defrosting is always employed. As a transient and nonlinear heat and mass transfer procession, defrosting performance directly affects the occupants’ thermal comfort. During defrosting, the metal energy storage values of indoor and outdoor coils are varied as their temperature fluctuations. It is therefore necessary to investigate the energy transfer procession in an air source heat pump unit and the effect of metal energy storage during defrosting. However, scarce of attentions were paid to this fundamental problem. In this study, two experimental cases with two-working-circuit and three-working-circuit outdoor coils were conducted basing on frost evenly accumulated on their surfaces. After four types of energy supply and five types of energy consumption during defrosting were calculated, a qualitative and quantitative evaluation on the metal energy storage effect was then given. As concluded, after the outdoor coil enlarged 50%, the metal energy storage effect can be changed from positive (0.33%) to negative (−2.18%). The percentages of energy consumed on melting frost and vaporizing retained water were both increased. Defrosting efficiency was improved about 6.08%, from 42.26% to 48.34%. Contributions of this study can effectively guide the design optimization of indoor and outdoor coils and promote the energy saving for air source heat pump units.
•Melting characteristics of clear ice under vertical CO2-laser is carried out.•Linear melting rate tends to increase and then decrease as laser power increases.•The maximum of instantaneous linear ...melting rate at 40 W is 13.95 mm/s.•The maximum energy efficiency at 20 W is 64.8 %.
Icing phenomenon widely exists and plays negative effects in aviation and electricity fields. Laser deicing technology is a typical non-contact and high-efficiency deicing method. To accurately predict and control the laser-induced ice melting process, an experimental study on melting characteristics of clear ice under vertical CO2-laser irradiation and natural convection is carried out, with the laser power varied at a range of 20–60 W. As resulted, the axial melting rate tends to increase and then decrease with the increase of laser power. The maximum of average and instantaneous axial melting rate at 40 W are 5.85 mm/s and 13.95 mm/s, respectively. The higher the laser power, the larger the peaks of maximum melting length. At 20 W and 60 W, the peaks of maximum melting length are 10.51 mm and 12.19 mm, respectively. There is little correlation between the deflection of angle and laser power. At 30 W and 50 W, the maximum angles of melting length are 0.77° and 2.52°, respectively. When the melting depth is smaller than 81.5 mm, the maximum energy efficiency at 20 W is 64.8 %, while when it is greater than 81.5 mm, the maximum energy efficiency at 60 W is 63.6 %. Results of this study are meaningful for the optimization of laser deicing technology.
A novel strategy for SO2 capture through multiple-site absorption in the anion of several azole-based ionic liquids is reported. An extremely high capacity of SO2 (>3.5 mol/mol) and excellent ...reversibility (28 recycles) were achieved by tuning the interaction between the basic anion and acidic SO2. Spectroscopic investigations and quantum-mechanical calculations showed that such high SO2 capacity originates from the multiple sites of interaction between the anion and SO2. These tunable azole-based ionic liquids with multiple sites offer significant improvements over commonly used absorbents, indicating the promise for industrial applications in acid gas separation.
Mitochondrial sirtuins, SIRT3–5, are NAD+-dependent deacylases and ADP-ribosyltransferases that are critical for stress responses. However, a comprehensive understanding of sirtuin targets, ...regulation of sirtuin activity, and the relationships between sirtuins remains a key challenge in mitochondrial physiology. Here, we employ systematic interaction proteomics to elucidate the mitochondrial sirtuin protein interaction landscape. This work reveals sirtuin interactions with numerous functional modules within mitochondria, identifies candidate sirtuin substrates, and uncovers a fundamental role for sequestration of SIRT3 by ATP synthase in mitochondrial homeostasis. In healthy mitochondria, a pool of SIRT3 binds ATP synthase, but upon matrix pH reduction with concomitant loss of mitochondrial membrane potential, SIRT3 dissociates. This release correlates with rapid deacetylation of matrix proteins, and SIRT3 is required for recovery of membrane potential. In vitro reconstitution experiments, as well as analysis of CRISPR/Cas9-engineered cells, indicate that pH-dependent SIRT3 release requires H135 in the ATP5O subunit of ATP synthase. Our SIRT3–5 interaction network provides a framework for discovering novel biological functions regulated by mitochondrial sirtuins.
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•Comprehensive mitochondrial sirtuin interactome elucidates sirtuin-binding partners•Mitochondrial sirtuin network identifies SIRT3-ATP synthase association•SIRT3 binds ATP5O in a stress- and pH-sensitive manner•SIRT3 links fuel utilization with membrane potential homeostasis
Upon loss of mitochondrial membrane potential, SIRT3 is released from the mitochondrial ATP synthase, and its return is necessary for a rapid restoration of mitochondrial health.
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•A novel one-pot method for efficient arsenic removal from ZnSO4 solution.•Ultrasonic field can enhance the oxidation effect of ozone and destroy the wrapper.•Compared to the lime ...method, the amount of precipitate can be reduced by 54.5%.•The reaction time is reduced by 60% compared to traditional methods.
Currently, removing arsenic (As) from ZnSO4 solution using lime presents several drawbacks, including high wet precipitate content, long reaction time, and the introduction of new impurities. In this study, we propose a novel ultrasonic (US) ozone one-pot method for effectively removing As from a high-arsenic ZnSO4 solution. In this method, as in ZnSO4 solution was removed by ultrasound enhanced ozone oxidation combined with zinc roasting dust (ZRD). No secondary pollution will occur with the addition of ZRD and ozone, as neither introduces new impurities. The experimental results show that under the conditions of initial As and Fe concentrations of 1640 mg/L and 2963 mg/L, US power of 480 W, frequency of 20 kHz, reaction temperature of 60 °C, reaction time of 1 h, ZRD dose of 12 g/L and gas flow rate of 900 mL/min, the removal rate of As can reach 99.4%. The introduction of US can further enhance the oxidation effect of ozone on As(III) and Fe2+ by increasing the solubility of ozone and promoting the production of OH radicals. Additionally, US cavitation and mechanical action increase the probability of contact between various reactants in the solution, facilitating the occurrence of reactions. US also reduces the aggregation of arsenic-containing precipitates and the encapsulation of ZRD by arsenic containing precipitates, thereby decreasing the amount of arsenic-containing precipitates. In comparison to the traditional lime method, this approach results in a significant reduction in the amount of arsenic-containing precipitate by 54.5% and a 60% decrease in the total reaction time. The As removal mechanism of our method encompasses ZRD neutralization, US-enhanced ozone mass transfer and decomposition, oxidation of As(III) and Fe2+, and adsorption and coprecipitation. Consequently, the proposed method provides a cost-effective, fast, safe and environmentally friendly alternative for treating arsenic-contaminated ZnSO4 solutions.
•Spray falling film of oily wastewater over a horizontal tube was investigated.•VOF model was used to simulate the gas-liquid falling film flow.•The non-uniform film flow, temperature and thickness ...distributions were analyzed.•The non-uniform heat transfer properties were quantitatively investigated.•The effects of oil content, spray density and tube diameter were studied.
Recently, the spray heat exchanger became an important technology in a sewage source heat pump (SSHP) to recover thermal energy from oily wastewater. Hence, it's necessary to study the heat transfer properties and its enhancements. In this paper, a numerical model with VOF method was established to study the oily wastewater spray falling film over a horizontal tube. The flow field, falling film distribution and temperature distribution and heat transfer coefficient were investigated, and the non-uniformity of flow, temperature and heat transfer were further analyzed. Regions of low level film thickness were found around tube suggesting the non-uniform axial and circumferential distribution, corresponding to low film temperature regions. The non-uniformity of heat transfer coefficient at different circumferential angles was evaluated showing severe non-uniformity in impingement and departure regions due to the intense impinging of falling wastewater at the top and instability of dropping flow at the bottom. Thereafter, the influence of oil content, spray density and tube diameter were studied. The increase in oil content led the flow pattern changed from sheet flow to column-sheet flow due to increase in viscosity, resulting to non-uniformity increase from 0.15 to 0.19. Compared to tube diameter of 25.4 mm, the 12.7 mm tube accelerated flow downstream, therefore, the non-uniformity at the top was weakened to 0.13 and the downstream non-uniformity was strengthened to 0.19. The higher spray density of 0.262 kg/m∙s reduced the negative effect of viscosity, enhanced the flow velocity and weakened the non-uniformity at the top. However, the increase in flow velocity raised the flow instability in downstream suggesting higher non-uniformity.
RNA interference (RNAi) represents a promising strategy for identification and validation of putative therapeutic targets and for treatment of a myriad of important human diseases including cancer. ...However, the effective systemic in vivo delivery of small interfering RNA (siRNA) to tumors remains a formidable challenge. Using a robust self-assembly strategy, we develop a unique nanoparticle (NP) platform composed of a solid polymer/cationic lipid hybrid core and a lipid-poly(ethylene glycol) (lipid-PEG) shell for systemic siRNA delivery. The new generation lipidâpolymer hybrid NPs are small and uniform, and can efficiently encapsulate siRNA and control its sustained release. They exhibit long blood circulation ( t â/â â¼8 h), high tumor accumulation, effective gene silencing, and negligible in vivo side effects. With this RNAi NP, we delineate and validate the therapeutic role of Prohibitin1 (PHB1), a target protein that has not been systemically evaluated in vivo due to the lack of specific and effective inhibitors, in treating non-small cell lung cancer (NSCLC) as evidenced by the drastic inhibition of tumor growth upon PHB1 silencing. Human tissue microarray analysis also reveals that high PHB1 tumor expression is associated with poorer overall survival in patients with NSCLC, further suggesting PHB1 as a therapeutic target. We expect this long-circulating RNAi NP platform to be of high interest for validating potential cancer targets in vivo and for the development of new cancer therapies.
Significance This study developed a new generation lipidâpolymer hybrid nanoparticle platform for effective systemic delivery of small interfering RNA (siRNA) to tumors, which represents a challenging hurdle for the widespread application of RNA interference (RNAi) in cancer research and therapy. With promising in vivo features such as long blood circulation, high tumor accumulation, and effective gene silencing, the hybrid siRNA nanoparticles were successfully used to reveal and validate a putative therapeutic target, Prohibitin1 (PHB1), in non-small cell lung cancer treatment. In vivo antitumor efficacy results and human tissue microarray analysis further suggested the feasibility of utilizing PHB1 siRNA nanoparticles as a novel therapeutic agent. This hybrid RNAi nanoparticle platform may serve as a valuable tool for validating potential cancer targets and developing new cancer therapies.
•A numerical study was conducted on a task/ambient air conditioning system.•The effects of envelope heat gain on energy consumption was studied.•The effects of envelope heat gain on thermal comfort ...was investigated.•Thermally neutral operating conditions were obtained.
There has been an increasing concern on thermal comfort in sleeping environments and its associated energy use in the past few years. To improve the thermal environment and to reduce energy use of air conditioning in bedrooms, applications of task/ambient air conditioning (TAC) systems were proposed and studied previously. It’s indicated that the TAC system can be well integrated with a bed. Due to the variation of the envelope heat gain in a bedroom during night, it is necessary to study the thermal environment inside a bedroom and the energy use of a TAC system for the bedroom at varying envelope thermal loads. Therefore, this paper reports on a numerical study on a TAC system applied to a bedroom with different envelope heat gains. The influences of envelope heat gain on energy consumption of the TAC system and the indoor thermal comfort were studied in this paper. The research results show that at supply air flow rate (Qs) of 50 l/s, energy consumption was increased from 47.78W to 213.11W, and the PMV value was increased from −1.69 to −1.29 with the increase in envelope heat gain from 3.11W to 155.6W. To make PMV equal to zero under different envelope heat gains, linear regression models between supply air parameters and PMV were built and solved. The obtained values form curves where PMV=0 and give a guide for operation of the TAC system. It was found that the calculation of energy consumption on these curves depends only on envelope heat gain.
Membraneless organelles (MLOs) formed via protein phase separation have great implications for both physiological and pathological processes. However, the inability to precisely control the ...bioactivities of MLOs has hindered our understanding of their roles in biology, not to mention their translational applications. Here, by combining intrinsically disordered domains such as RGG and mussel-foot proteins, we create an in cellulo protein phase separation system, of which various biological activities can be introduced via metal-mediated protein immobilization and further controlled by the water-soluble chlorophyll protein (WSCP)-a remarkably stable, red-light-responsive singlet oxygen generator. The WSCP-laden protein condensates undergo a liquid-to-solid phase transition on light exposure, due to oxidative crosslinking, providing a means to control catalysis within synthetic MLOs. Moreover, these photoresponsive condensates, which retain the light-induced phase-transition behavior in living cells, exhibit marked membrane localization, reminiscent of the semi-membrane-bound compartments like postsynaptic densities in nervous systems. Together, this engineered system provides an approach toward controllable synthetic MLOs and, alongside its light-induced phase transition, may well serve to emulate and explore the aging process at the subcellular or even molecular level.
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