Investigations on High-Speed Flash Boiling Atomization of Fuel Based on Numerical Simulations

Flash boiling atomization(FBA)is a promising approach for enhancing spray atomization,which can generate a fine and more evenly distributed spray by increasing the fuel injection temperature or reducing the ambient pressure.However,when the outlet speed of the nozzle exceeds 400 m/s,investigating high-speed flash boiling atomization(HFBA)becomes quite challenging.This difficulty arises fromthe involvement ofmany complex physical processes and the requirement for a very fine mesh in numerical simulations.In this study,an HFBA model for gasoline direct injection(GDI)is established.This model incorporates primary and secondary atomization,as well as vaporization and boilingmodels,to describe the development process of the flash boiling spray.Compared to lowspeed FBA,these physical processes significantly impact HFBA.In this model,the Eulerian description is utilized for modeling the gas,and the Lagrangian description is applied to model the droplets,which effectively captures the movement of the droplets and avoids excessive mesh in the Eulerian coordinates.Under various conditions,numerical solutions of the Sauter mean diameter(SMD)for GDI show good agreement with experimental data,validating the proposed model’s performance.Simulations based on this HFBA model investigate the influences of fuel injection temperature and ambient pressure on the atomization process.Numerical analyses of the velocity field,temperature field,vapor mass fraction distribution,particle size distribution,and spray penetration length under different superheat degrees reveal that high injection temperature or low ambient pressure significantly affects the formation of small and dispersed droplet distribution.This effect is conducive to the refinement of spray particles and enhances atomization.

Effect and Mechanism of Dicliptera chinensis Polysaccharide on miR-141/AMPK/SIRT1 Signaling Pathway in Rats with NAFLD

[Objectives]Non-alcoholic fatty liver disease(NAFLD)rat model was established by feeding high-fat and high-sugar fodder to rats,and the protective effect of Dicliptera chinensis polysaccharide(DCP)on NAFLD rats was studied to explore its potential mechanism.[Methods]45 SD rats were randomly divided into 4 groups:normal control group,model control group and DCP treatment groups(100 and 300 mg/kg).The rats in the normal control group were fed with ordinary fodder,and the rats in other groups were fed with high-fat and high-sugar diet for 14 weeks to establish NAFLD model.From the 9^(th)week,the rats in the DCP treatment groups were given different doses of DCP by intragastric administration(5 mL/kg)for 6 weeks.After the last intragastric administration,the rats fasted for 16 h,and the serum and liver of rats were collected for detection.Hematoxylin-eosin(HE)staining was conducted to observe the histopathological changes of rat liver,and alanine aminotransferase(ALT),aspartate aminotransferase(AST),superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),malondialdehyde(MDA),triglyceride(TG),total cholesterol(TC),low density lipoprotein cholesterol(LDL-C),and high density lipoprotein cholesterol(HDL-C)were detected by biochemical method.Interleukin-6(IL-6),interleukin-1β(IL-1β),tumor necrosis factor(TNF-α)and micrornA-141(micro RNA-141)were detected by reverse transcription-polymerase chain reaction(RT-PCR).The expression of SIRT1 and adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK)in rat liver was detected by western blot.[Results]Compared with the model control group,the inflammatory damage and steatodegeneration of rats in the DCP groups were relieved to varying degrees,and the number of lipid vacuoles significantly reduced.The ALT,AST,TC,TG and LDL-C content in the serum and MDA content in the liver tissue decreased to varying degrees,while the HDL-C,SOD and GSH-Px content increased.The expression of SIRT1 and AMPK increased,while the expression of miR-141,TNF-α,IL-6 and IL-1βdeclined,and the DCP 300 mg/kg treatment group had better improvement effect.[Conclusions]DCP had a certain protective effect on NAFLD rats,which may be related to the regulation of miR-141/AMPK/SIRT1 signaling pathway.

Investigation the improvement of high voltage spinel LiNi_(0.5)Mn_(1.5)O_(4) cathode material by anneal process for lithium ion batteries

The spinel LiNi_(0.5)Mn_(1.5)O_(4)(LNMO)has been attracted great attention as lithium ion cathode material due to its high voltage and large energy density.However,the practical application of LNMO is still limited by poor cycling stability.Herein,to improve the cycling stability of spinel LNMO,it was treated with anneal process at 900℃for 2 h after prepared by traditional solid-state method(LNMO-A).LNMO-A sample presented better electrochemical property especially under high rate,with capacity of 91.2 mAhg^(-1) after 1000 cycles under 10 C.Its superior electrochemical property was ascribed to the anneal process,resulting a stable crystal structure,indicated by XRD and Raman results of electrodes after 1000 cycles under 10 C and the longer solid-solution reaction,revealed by in-situ XRD.In addition,the optimized particle size,micro morphology and the larger BET area surface induced by the recrystallization in anneal process also contributes to its superior electrochemical property.What's more,the thin layer,which interacted LNMO-A particles with each other,induced by particles remelting in anneal process is also beneficial for its excellent electrochemical property.This study not only improved the electrochemical properties by anneal process,but also revealed the origins and mechanisms for its improvement.

Protective Effects of Yinzhihuang Combined with Metformin on Nonalcoholic Fatty Liver Diseases Based on PPAR-αSignaling Pathway

[Objectives]To explore the protective effects and mechanism of Yinzhihuang combined with metformin on nonalcoholic fatty liver diseases(NAFLD)based on PPAR-αsignaling pathway.[Methods]54 male SD rats were randomly divided into 2 groups,namely normal group(12 rats)and high-fat feed group(42 rats).After 8 weeks,2 rats were randomly selected from each group.After pathological examination confirmed the success of the NAFLD model,the high-fat feed group was divided into model group,Yinzhihuang(9000 mg/kg),metformin group(200 mg/kg),Yinzhihuang combined with metformin group(4500 mg/kg+100 mg/kg),10 rats in each group.Except the normal group and the model group,the other groups were given treatment drugs at the same time,one time a day,on the fifth weekend of the experiment,at the last time of administration,fasting but giving water for 16 h,then collected blood and liver tissue.Biochemical method was used to detect AST and ALT in serum and SOD,MDA,GSH-px biochemical indicators in liver tissue;enzyme-linked immunosorbent assay(ELISA)was used to detect the levels of TNF-α,IL-6 and TGF-βin liver tissue;Western blot was used to detect the expression of peroxisome proliferators-activated receptor-α(PPAR-α)protein in rat liver tissue.[Results]Compared with the model group,the serum levels of ALT,AST and MDA in liver tissue of model group rats were significantly increased;the levels of SOD and GSH-px in liver tissue were significantly increased;TNF-αand IL-6 and TGF-βcontents in liver tissue were significantly increased.[Conclusions]Both Yinzhihuang and metformin have a therapeutic effect on NAFLD rats,and the effect of combined application of the two is significantly better than the intervention effect of Yinzhihuang or metformin alone,the mechanism is possibly associated with the regulation of PPAR-αsignaling pathway.

Effects of Mogroside V on Glucose and Lipid Metabolism in High Fat Diet Mice

[Objectives]To explore the effects and mechanism of mogroside V(MV)on glucose and lipid metabolism in high-fat diet(HFD)mice.[Methods]The experiment fed mice with high-fat diet for 8 weeks,and 40 mice with successful modeling were randomly divided into normal group,model group,and MV dose group(100,200 mg/kg),with 10 mice in each group.From the ninth week,the MV dose group was given intragastric administration,and the normal group and the model group were given an equal volume of distilled water by intragastric administration for 6 weeks,then killed and blood samples and livers were collected.Serum triglycerides(TG),total cholesterol(TC),low density lipoprotein cholesterol(LDL-C),high density lipoprotein cholesterol(HDL-C),free fatty acids(FFA),Advanced glycation end products(AGE-P)-peptides(AGE-P)and glycosylated hemoglobin(HbA1c)content,and TG and hepatic glycogen content in liver were detected by biochemical method.Fasting blood glucose(FBG)was measured by glucose oxidase method.The fasting serum insulin(FINS)content was detected by enzyme-linked immunosorbent assay(ELISA),and the insulin resistance index(HOMA-IR)was calculated.Oil red O staining was used to observe the fat deposition in liver tissue.[Results]MV(100,200 mg/kg)dose groups could significantly down-regulate the contents of TC,TG,LDL-C,FBG,FINS,AGE-P and HbA1c and HOMA-IR,and up-regulate HDL-C and hepatic glycogen content and reduce the fat deposits.[Conclusions]The mechanism of MV regulating glucose and lipid metabolism in mice may be related to the regulation of insulin resistance.

Characteristics of Sources and Sinks of Yugu 18

[Objectives] The study aimed to discuss the high-yield mechanism of Yugu 18.[Methods] The characteristics of sources and sinks of Yugu 18 with high quality, high yield, wide adaptability and multi-resistance to diseases were studied by using Jigu 18 as the control variety.[Results] Yugu 18 was superior in sink capability and the ability to fill sinks. In the filling period, its photosynthetic capacity was strong, and grain-leaf ratio was high. Photosynthetic products had a great contribution to grain filling after flowering, and the coordination between sources and sinks was good.[Conclusions] The research provides theoretical basis for the breeding and cultivation of high-yield foxtail millet.

A Resource for Inactivation of MicroRNAs Using Short Tandem Target Mimic Technology in Model and Crop Plants

microRNAs (miRNAs)are endogenous small non-coding RNAs that bind to mRNAs and target them for cleavage and/or translational repression,leading to gene silencing.We previously developed short tandem target mimic (STTM)technology to deactivate endogenous miRNAs in Arabidopsis.Here,we created hundreds of STTMs that target both conserved and species-specific miRNAs in Arabidopsis,tomato,rice,and maize,providing a resource for the functional interrogation of miRNAs.We not only revealed the functions of several miRNAs in plant development,but also demonstrated that tissue-specific inactivation of a few miRNAs in rice leads to an increase in grain size without adversely affecting overall plant growth and development.RNA-seq and small RNAseq analyses of STTM156/157 and STTM165/166 transgenic plants revealed the roles of these miRNAs in plant hormone biosynthesis and activation,secondary metabolism,and ion-channel activity-associated electrophysiology,demonstrating that STTM technology is an effective approach for studying miRNA functions.To facilitate the study and application of STTM transgenic plants and to provide a useful platform for storing and sharing of information about miRNA-regulated gene networks,we have established an online Genome Browser (https://blossom.ffr.mtu.edu/designindex2.php) to display the transcriptomic and miRNAomic changes in STTMinduced miRNA knockdown plants.

Virus-induced Gene Silencing in Eggplant(Solanum melongena)

Eggplant （Solanum melongena） is an economically important vegetable requiring investigation into its various genomic functions. The current limitation in the investigation of genomic function in eggplant is the lack of effective tools available for conducting functional assays. Virus-induced gene silencing （VIGS） has played a critical role in the functional genetic analyses. In this paper, TRV-mediated VIGS was successfully elicited in eggplant. We first cloned the CDS sequence of PDS （PHYTOENE DESATURASE） in eggplant and then silenced the PDS gene. Photo-bleaching was shown on the newly-developed leaves four weeks after agroinoculation, indicating that VIGS can be used to silence genes in eggplant. To further illustrate the reliability of VIGS in eggplant, we selected Chl H, Su and CLA1 as reporters to elicit VIGS using the high-pressure spray method. Suppression of Chl H and Su led to yellow leaves, while the depletion of CLA1 resulted in albino. In conclusion, four genes, PDS, Chl H, Su （Sulfur）, CLA1, were down-regulated significantly by VIGS, indicating that the VIGS system can be successfully applied in eggplant and is a reliable tool for the study of gene function.

Insight into the effect of graphene coating on cycling stability of LiNi_(0.5)Mn_(1.5)O_(4):Integration of structure-stability and surface-stability

Graphene has presented promising features for application in lithium ion batteries(LIBs)due to its superior electronic conductivity and high surface area.It has been successfully used for modifying cathode materials to meet the increasing demand for LIBs with longer cycle life.However,the improving effect of graphene on cycling stability is still unclear,which restricts its further application in LIBs.Herein,graphene coated hollow sphere-like structure LiNi0.5Mn1.5O4(LNMO)wasdesigned and the improvement mechanism of graphene coating on LNMO’s cycling stability was investigated.The results show that graphene coating not only contributes to suppress structural deformation from mechanistic reaction and extend solid-solution reaction,but also helps protect electrode from corrosion by the products from electrolyte decomposition and suppress the generation of surface defects,especially at high temperature.Owing to graphene coating,graphene coated LNMO can deliver a discharge capacity of 91 mAh g1 with high capacity retention of 82.5%after 1000 cycles under 20C and 83.8 mAh g1 with 94.5%capacity retention after 100 cycles under 2C at 55C.This work deeply explores the effect of graphene coating on cycling stability from crystal stability and surface stability,which will help a wider application of graphene in energy storage field.