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Due to the high cost and long lifecycle of manned Mars exploration missions, in-situ resource utilization technology, including Mg/CO 2 processes, has attracted increasing attention. At present, Mg/CO 2 engines face the challenges of long ignition delay, serious carbon deposition, and low combustion efficiency. The root of these challenges lies in the Mg/CO 2 combustion reaction. Therefore, based on an Mg-based powder prepared by mechanical mixing combined with ultrasonic dispersion, the effects of various nano-metal oxides (CuO, Fe 2 O 3 , MnO 2 , MoO 3 , and Bi 2 O 3) on the ignition and combustion of Mg particles in CO 2 were studied through constant volume combustion experiments. It was found that MoO 3 undergoes the optimal covered-type of binding with Mg particles. The other oxides achieved embedded-type binding, of which MnO 2 binding was the worst. The enhanced ignition and combustion effects of Bi 2 O 3 and CuO were best. Thermogravimetric analysis found that CuO and Bi 2 O 3 improve combustion efficiency by lower ignition temperatures, inhibiting low-temperature oxidation reaction and increasing reaction ratio. • The enhancement effects of metal oxides on ignition and combustion of Mg particles in CO 2 are firstly studied. • The binding abilities of different nano-metal oxides to micro-Mg particles are analyzed. • The enhancement effects of CuO and Bi 2 O 3 on ignition and combustion of Mg particles in CO 2 are analyzed. • The influences of metal oxide addition ratio on enhancement are analyzed. [ABSTRACT FROM AUTHOR]

The production of return propellant through Martian in-situ resources has been proposed in the assumptions of Mars exploration missions. The Mg/CO 2 scheme is one of these approaches in which powdered magnesium comes from the Earth as fuel and CO 2 is collected on the surface of Mars as the oxidant. The propellant of Mg/CO 2 engines has a good storage stability, has no chemical reactions in the in-situ resource utilization process, and contains a simple structure; thus, it is regarded as one of the technologically less complex choices for missions on Mars. However, the low specific impulse of Mg/CO 2 engines requires evaluating their applications and performance. Three Mg/CO 2 application scenarios (Ascent Vehicle, Hopper, and Two-stage Returnable Aircraft) are reviewed here, and two of them are estimated in detail from the established motion models. It is found that when a Mg/CO 2 engine is used as an Ascent Vehicle, a two-stage rocket is more suitable. The propellant carried from Earth for Mg/CO 2 engines could be reduced by 27.7% compared with the conventional storable UDMH/N 2 O 4 (specific impulse is 330 s) two-stage rocket. The saved propellant is largest when the total velocity pulse is approximately 3430 m/s. When Mg/CO 2 engines are used as a jump vehicle "Hopper", the increased maximum thrust, engine working time, and total jump times decrease the marginal benefit, which means that these parameters cannot be too large. Based on the Ascent Vehicle and Hopper schemes, a Two-stage Returnable Aircraft is proposed for material and personnel circulation between different Mars bases. • Detailed motion models of Mars aircrafts with Mg/CO 2 engine are firstly established. • The advantages of Mg/CO 2 engine as Mars Ascent vehicle are analyzed in detail. • The influence of key parameters on the performance of Mars jump vehicle "Hopper" with Mg/CO 2 engine is obtained. • A new Mars two-stage returnable aircraft is conceived. [ABSTRACT FROM AUTHOR]

This work aimed to explore the underlying mechanism of plasma-activated water (PAW) promoting the heat-induced aggregation of myofibrillar protein (MP). The results of particle size and atomic force microscope indicated that PAW accelerated the aggregation of MP with PAW 60 showing the densest and most homogeneous crosslinking morphology. Raman spectroscopy showed that about 4.11% of the α-helix in PAW 60 changed to β-sheet during heating. The effects of PAW on the oxidation of MP were assessed in terms of sulfhydryl, disulfide bonds, carbonyl content and surface hydrophobicity. The amino acid composition revealed that the content of tyrosine dropped from 45.43 mg/g of PAW 0 to 37.35 mg/g of PAW 240 , indicated that tyrosine in MP was converted to dityrosine by PAW. These results indicate that PAW promotes the oxidation of MP and further changes in intra- and inter-molecular interactions, which provides a theoretical basis for PAW promoting thermal aggregation of MP. • PAW 60 showed the densest and most uniform network cross-linking structure at Stage 3. • PAW aided in the transition of secondary structure of MP from α-helix to β-sheet during heating. • PAW promoted time-dependently the oxidation of the sulfhydryl groups to disulfide bonds. • PAW promoted the aggregation of MP by modifying tyrosine to dityrosine. [ABSTRACT FROM AUTHOR]

Bacterial foodborne diseases have become a growing global health concern, and nucleic acid-based analysis is considered as a promising approach for rapid identification of foodborne pathogens. Accordingly, nucleic acid isolation becomes the prerequisite first step for subsequent bioanalysis. However, current nucleic acid extraction suffers from operation time delayed, amplification inhibited by chemicals, or bulky instruments required. Here, we presented an ultrafast bacterial cell lysis induced by corona discharge within 40 s and combined it with loop-mediated isothermal amplification (LAMP) for the first time to achieve rapid and convenient detection of foodborne pathogens. Firstly, the viability and morphological changes revealed that corona discharge could destabilize bacterial cell envelope and eliminate more than 90% of Salmonella enterica (S. enterica) or Staphylococcus aureus (S. aureus) within 40 s. More surprisingly, more DNA were released from 100-103 CFU of electrical lysed S. enterica than equivalent thermal lysed ones, manifesting advantages of corona discharge on shorter preparation time and greater yields of DNA. Furthermore, the advantages of this ultrafast bacterial cell lysis were leveraged when collaborating with colorimetric LAMP. After conducting colorimetric LAMP in a water bath at 63 °C for 1 h, we could visually detect released DNA from 100 CFU of electrical lysed S. enterica and 103 CFU of electrical lysed S. aureus , respectively. Finally, we validated the applicability of the electrical lysis combined with LAMP reaction to detect (viable) S. enterica and S. aureus in artificially spiked pork samples. Therefore, we provided a rapid and convenient bioanalysis platform integrating an ultrafast electrical lysis and LAMP detection, opening up its extensive applications for versatile pathogens in resource-limited settings. • Ultrafast bacterial cell lysis based on corona discharge within 40 s. • Corona discharge outperformed on cell membrane rupture and bacterial DNA release. • Corona discharge based cell lysis had no side effects on subsequent DNA analysis. • Corona discharge based cell lysis was first combined with LAMP for bioanalysis. [ABSTRACT FROM AUTHOR]

The improvement of the ignition and combustion performance of aerospace engines under extreme conditions such as high altitude, low temperature, low pressure, and high speed is a research topic of broad and current interest. Plasma technology has attracted increasing attention due to its significant potential in improving ignition and combustion performance. Scientists and engineers have conducted numerous investigations and experiments on the use of plasma technology in aerospace engines, especially in aviation gas turbine engines, driving the research and applications of plasma-assisted ignition (PAI) and plasma-assisted combustion (PAC). The aim of this comprehensive review paper is to summarize and discuss the developments and applications of PAI and PAC in the fields of aerospace engines during the last ten years, including ignition, lean blow-out, combustion efficiency, emission, outlet temperature distribution quality, combustion stability, and fuel distribution. This review paper mainly focuses on experimental research progress. We also introduce new applications of PAI and PAC in novel aerospace engines and discuss the prospects for its practical implementation. [ABSTRACT FROM AUTHOR]

• TS-1 nanozeolite was achieved in a concentrated gel system through a two-step synthesis method. • The effect of the addition of L-lysine on the structure of zeolite was proposed. • The formation mechanism of nanozeolite was speculated. • TS-1 nanozeolite showed the excellent catalytic performance in hydroxylation of benzene. L-lysine is used as a crystallization regulator, and a two-step synthesis method is adopted in a concentrated gel system, which provides a new route to synthesize of nano-sized TS-1 zeolite. The new synthesis strategy was used to successfully synthesize TS-1 zeolite with a particle size less than 100 nm. The rate of crystal nucleation is faster than the crystal growth at the low temperature in the first step. Introduction of L-lysine can prevent crystal growth to form nano-sized TS-1 zeolite at the high temperature in the second step. Meanwhile, L-lysine decrease the pH value of the gel system, which is favorable for Ti atoms to incorporate the TS-1 framework. TS-1 nanozeolite can effectively reduce the diffusion resistance, and nanozeolite has a large specific surface area and high stability. Therefore, TS-1 nanozeolite exhibits the excellent catalytic performance during the hydroxylation of benzene. The conversion of benzene has been greatly improved and the types of by-products are effectively reduced. The conversion of benzene reached 50.2%, and the yield of phenol was 30.8% without by-product benzoquinone. TS-1 nano-zeolite as a catalyst for benzene hydroxylation shows great potential in industrial application. [Display omitted] [ABSTRACT FROM AUTHOR]

This study investigated the mechanism of ethanol enhancing the gel properties of heat-induced silver carp (Hypophthalmichthys molitrix) surimi gels. The presence of ethanol reduced the thermal stability of surimi protein, and the denaturation temperature of myosin decreased by approximately 7 °C in the presence of 5% ethanol. The gel strength, textural characteristics, and storage modulus (G′) of the gels improved depending on ethanol levels, while the water holding capacity (WHC) remained steady. Adding ethanol stabilized the α-helix and β-sheet in the protein structures of the gels, reducing the content of the random coil. Appropriate heat denaturation rate induced by ethanol increased protein cross-linking, which may relate to forming more disulfide bonds. In addition, ethanol incorporation promoted the formation of more isopeptide bonds catalyzed by transglutaminase (TGase) and weakened the hydrolysis of surimi proteins by cathepsins, further enhancing the formation of a dense and uniform gel network. • Ethanol promoted protein cross-linking and enhanced the gel properties. • The enhancement mechanism of ethanol on the gel performance was investigated. • Ethanol increased the ordered secondary structure of proteins during heating. • Proper thermal denaturation rate of proteins allows more disulfide bonds to form. • Ethanol promoted more isopeptide bond formation and weakened protein hydrolysis. [ABSTRACT FROM AUTHOR]

• Arg combined with TGase improved the gel properties of low-salt surimi induced by MW. • A compact network of low-salt surimi gel was obtained if Arg was added before TGase. • Arg increased proportion of immobilized water and decreased proportion of free water. • Arg induced a shift of α-helix bands and increase in definition of β-sheet bands. • The binding sites between Arg and myosin were revealed via molecular docking technique. The reduction of the salt content of foods is of interest for health reasons. The present study showed that low-salt surimi gels could be produced using a combination of l -arginine (Arg) and transglutaminase (TGase) under microwave (MW) irradiation. The low-salt surimi gels produced by MW had similar physicochemical properties as regular-salt surimi gels produced by conventional two-stage water bath heating. Compared to low-salt surimi gels containing TGase alone, Arg increased the water holding capacity and gel strength (P < 0.05) and promoted the formation of a more homogeneous and compact three-dimensional gel network. As a result, there was a significant increase in the proportion of immobilized water and decrease in the proportion of free water (P < 0.05). The nature of the binding sites between Arg and myosin heavy chain was predicted using the molecular docking simulations analysis. These results may be useful for the development of low-salt surimi products. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oleogel improved low-salt surimi texture with better water retention. • Oleogel addition reduced surimi gel's digestibility due to high cross-linking. • Surimi gel digestive solutions' antioxidant properties were improved by oleogel. • Lower-molecular weight peptides were produced after composite surimi digestion. To improve nutritional health, a low-salt (0.5 %) silver carp (Hypophthalmichthys molitrix) surimi gel with α-tocopherol, soybean oil, and glyceryl monostearate oleogel was fabricated and evaluated for textural qualities, lipid oxidation, and in-vitro digestion analysis. Based on the texture profile analysis, gel strength, water holding capacity (WHC), rheological, protein secondary structure, and microstructural examination, 5 % oleogel addition to low-salt surimi exhibited similar physicochemical properties to regular-salt surimi gels. By crosslinking myosin and filling protein network voids, the oleogel increased surimi gel density. Increasing oleogel content improved the physicochemical qualities of heat-induced surimi, causing protein aggregation during digestion and reducing digestibility. The presence of oleogel altered protein secondary structure, reducing α-helix content and increasing β-sheet and other structures, enhancing WHC and gel strength of low salt surimi. Adding oleogel improved the antioxidant activity of digestive solutions. This study will help understand myosin-oleogel interaction and the development of sustainable and nutritious surimi-based foods. [ABSTRACT FROM AUTHOR]

In order to reduce the engine size and mass of spacecraft for Mars missions, powdered magnesium (Mg) and carbon dioxide rocket engines should use liquid carbon dioxide (liquid CO 2) as their oxidizer. Experimental studies are carried out on the characteristics of liquid CO 2 feed, powdered Mg feed, engine ignition, combustion, and pressure oscillation. Results show that both the feeding systems of liquid CO 2 and powdered Mg work stably. Although the use of liquid CO 2 makes ignition more difficult, reliable ignition and a stable flame are achieved by means of multi-step ignition. The Damköhler number, L /[ v j × (t i + t b)], incorporates the parameters of pre-combustion chamber length, powder-injection velocity, particle ignition delay, and burning time. Successful ignition is indicated by Damköhler number>1. Fluctuations in the powdered Mg feeding flowrate will cause serious combustion chamber pressure oscillation, whose maximum relative amplitude can be suppressed from 5.3% to 1.8% by choosing a suitable fluidization gas. Serious depositions are generated in the pre-chamber, which influence the propellant injection process and stable combustion process. The maximum relative amplitude of combustion pressure oscillation caused by this problem can grow up to 6%. The combustion efficiency of the engine reaches 83%, validating the feasibility of the powdered Mg and liquid CO 2 rocket engine. • The liquid CO 2 is firstly used as the oxidizer of powdered magnesium and carbon dioxide rocket engine in experiments. • A criterion indicating successful ignition is established. • The coupling mechanism between fluctuations of Mg powder flow rate and combustion chamber pressure is obtained. • The feasibility of the powdered Mg and liquid CO 2 rocket engine's working principle is verified. [ABSTRACT FROM AUTHOR]

The erosive burning in solid rocket motor is partly caused by heat flux increment effect of dense high-temperature droplet jet impact process, of which the basic physical process is single molten droplet impact solid wall. However, due to the complex process in combustion chamber, until now, the erosion mechanism under such conditions has not been scientifically described. In this study, with the combustion chamber condition being simulated, the bouncing process of single molten aluminum droplet/wall impact was obtained experimentally. The theoretical model about droplet contact time as well as the maximum spreading factor were modified based on the experiment data. The theoretical heat transfer model accounting for single aluminum droplet/wall impact process was established, with the assumption of a composite structure consisting of solid material and air cavities on the solid wall surface. The theoretical predicted magnitude order of heat flux between droplet and solid wall surface is approximately 10 3 ∼ 10 4 W/cm2, and the heat transferred to the wall is approximately 10 − 6 ∼ 10 − 5 J for single droplet impact. [ABSTRACT FROM AUTHOR]

• A newly isolated phages (IME184) can specifically infect the Klebsiella pneumoniae. • Phage genome composed of 44,598 bp with a GC content of 50.3%. • IME is classified as an Autographiviridae bacteriophage. Klebsiella pneumoniae, a multidrug resistant bacterium that causes nosocomial infections including septicemia, pneumonia etc. Bacteriophages are potential antimicrobial agents for the treatment of antibiotic resistant bacteria. In this study, a novel bacteriophage IME184, was isolated from hospital sewage against clinical multi-drug resistant Klebsiella pneumoniae. Transmission electron microscopy and genomic characterization exhibited this phage belongs to the Molineuxvirinae genus, Autographiviridae family. Phage IME184 possessed a double-stranded DNA genome composed of 44,598 bp with a GC content of 50.3%. The phage genome encodes 57 open reading frames, out of 26 are hypothetical proteins while 31 had assigned putative functions. No tRNA, virulence related or antibiotic resistance genes were found in phage genome. Comparative genomic analysis showed that phage IME184 has 94% similarity with genomic sequence of Klebsiella phage K1-ULIP33 (MK380014.1). Multiplicity of infection, one step growth curve and host range of phage were also measured. According to findings, Phage IME184 is a promising biological agent that infects Klebsiella pneumoniae and can be used in future phage therapies. [ABSTRACT FROM AUTHOR]

• A virulent S. maltophilia phage BUCT598 was isolated. • Genome sequencing and characterization of phage BUCT598 showed that the phage was a novel and highly infectious phage. • Phage BUCT598 has dual resistance to extreme acidic and alkaline environments. Stenotrophomonas maltophilia (S. maltophilia) is an important Gram-negative opportunistic pathogen that is widely distributed in nature. S. maltophilia is highly drug-resistant because of its intrinsic properties and acquired drug resistance involving multiple molecular mechanisms, which creates a critical situation for infection therapy. Hence, there is an urgent need for alternative antimicrobial strategies to combat S. maltophilia. Herein, a novel S. maltophilia bacteriophage (phage) in family Podoviridae , named BUCT598, was isolated from hospital sewage and characterized to evaluate its potential as an antibacterial agent. The one-step growth curve showed that its latent period and burst size were approximately 30 min and 165 PFU/cell, respectively. Furthermore, phage BUCT598 survived within an extremely broad pH range (1–11), indicating its outstanding tolerance to both extremely acidic and extremely alkaline conditions. The whole-genome sequence of phage BUCT598 showed that it was a linear double-stranded DNA genome of 43,581 bp and 60% GC content. We identified 55 putative gene products involved in DNA replication, packaging, structure, and cell lysis. Whole-genome sequence comparisons among closely related phages indicated that phage BUCT598 had the highest sequence similarity with S. maltophilia phage BUCT609, with 52% query coverage and 76.40% identity, suggesting that it is a novel phage. Our findings indicate the great potential of phage BUCT598 as an alternative antimicrobial agent to eliminate S. maltophilia , and provide additional evidence that will help to understand how phages adapt and evolve under extreme environmental conditions, thereby opening up more extensive biotechnology applications of phages. [ABSTRACT FROM AUTHOR]

• Tilapia fillets treated by the polyphenols were prepared at −4 °C in 49 days. • Polyphenol treatments retarded the degradation of myofibril in the muscle tissue. • Polyphenol inhibited the proliferation of bacteria (Pseudomonas and Acinetobacter). • Procyanidin treatment extended the predicted shelf life by 25 days. • The inhibition mechanism of texture deterioration for polyphenol was illuminated. The inhibition mechanism of the texture deterioration of tilapia fillets after treatment with polyphenols during partial freezing for 49 days was studied. Carnosic acid (CA), procyanidin (PA), quercetin (QE), and resveratrol (RSV) treatments had significantly higher hardness values (over 230 g) than the control group (183 g) on day 49 (P < 0.05). Polyphenol treatments were effective in delaying the protein degradation, lipid oxidation and spoilage microbe growth. Moreover, the kinetic model showed that the predicted shelf life of tilapia fillets treated with PA (102 d) was extended by 25 d compared to the control group (77 d). It was the proposed possible mechanism that polyphenols comprehensively maintained the protein conformation (increased hydrogen bonds and decreased disulfide bonds) and retarded protein denaturation and degradation, protecting the texture of the fillets. Therefore, polyphenols can be used to maintain texture and extend the shelf life of tilapia fillets during partial freezing. [ABSTRACT FROM AUTHOR]