Computational fluid dynamics-discrete element method simulation of stirred tank reactor for graphene production

Liquid phase exfoliation(LPE)process for graphene production is usually carried out in stirred tank reactor and the interactions between the solvent and the graphite particles are important as to improve the production efficiency.In this paper,these interactions were revealed by computational fluid dynamics–discrete element method(CFD-DEM)method.Based on simulation results,both liquid phase flow hydrodynamics and particle motion behavior have been analyzed,which gave the general information of the multiphase flow behavior inside the stirred tank reactor as to graphene production.By calculating the threshold at the beginning of graphite exfoliation process,the shear force from the slip velocity was determined as the active force.These results can support the optimization of the graphene production process.

Bleomycin inhibits CLEC14A to attenuate the progression of extracranial arteriovenous malformations

Background:We previously reported that interstitial injection of bleomycin(BLM)reduces the size of early-stage extracranial arteriovenous malformation(AVM).Here,we sought to investigate the potential mechanism of BLM in treating extracranial AVM.Methods:Samples of human extracranial AVM(n=3)with no pharmacological treatment were harvested.AVM endothelial cells were isolated and cultured in primary cell culture.The transcriptome was examined using RNAsequencing,and differentially expressed C-type lectin domain family 14 member A(CLEC14A)was validated at the transcriptomic and protein levels.Immunocytochemical staining of CLEC14A was performed in samples of human extracranial AVM,with and without BLM treatment.Results:Through second-generation sequencing,we found that the expression of 5689 genes were differentially increased or decreased following 24-h BLM stimulation.We found that CLEC14A may play an important role in the progression of AVM and can be inhibited by BLM treatment.Conclusion:BLM inhibited CLEC14A expression to attenuate the progression of AVM.

Intralesional Interstitial Injection of Bleomycin for Management of Extracranial Arteriovenous Malformations in Children

Background Despite many advances in the treatment for extracranial arteriovenous malformations(AVMs),they still result in tedious dissection and potential unacceptable complications,particularly in children.Therefore,this study aimed to investigate the efficacy and safety of intralesional interstitial injection of bleomycin for the treatment of children with AVMs.Methods A total of 10 children(6 boys and 4 girls)with AVMs were treated with serial interstitial bleomycin injections between May 2014 and January 2017.Maximum single doses of 15 U and 1 U/kg per session were administered for six sessions at a 1-month interval.Therapeutic effectiveness was evaluated and classified into four categories:complete response(CR),partial response(PR),no response,and worsening at 3 months after the last session.Further clinical follow-up outcomes were classified as improved,stable,or aggravated.Adverse events were recorded according to the Society of Interventional Radiology classification.Results All 10 children completed the sessions and follow-ups.CR occurred in 3(30%)patients,PR in 6(60%),and no response in 1(20%).Minor complications(class A)included maculopapular rash,bulla,vomiting,and hyperpigmentation,whereas no major complications occurred.Conclusion Intralesional interstitial injection of bleomycin is a feasible approach for the treatment of AVMs in children and provides safe and effective outcomes.This method may be an earlier treatment alternative in children to prevent potential destructive progression,considering the serious complications of currently available therapeutic methods.

Modeling of pyridine synthesis process in a coupled fluidized bed reactor

To obtain the optimal operating conditions of a coupled reactor for pyridine synthesis,reactor modeling process is carried out in this paper.During the modeling process,the flow hydrodynamics,heat transfer behavior,inter-phase mass transfer behavior and reaction kinetics were taken into consideration consequently.Further,a regression program based on least square method was proposed to regress the model parameters.The prediction results agreed well with the experimental results with an average deviation of 5.9%.Finally,by setting suitable aim function,the optimal operating conditions of the coupled reactor for pyridine synthesis were determined.

Continuous reaction performances of benzene alkylation with long chain olefins catalyzed by ionic liquid

Based on a compulsive mixing-reacting-sepa-rating-recycling small experimental setup,the continuous reaction performances of benzene alkylation with long chain olefins catalyzed by[BMIM]Cl-AlCl 3 ionic liquid were investigated.Three different situations including normal continuous operation mode(reagent materials),sidetrack feeding from different axial positions along the static mixing reactor(reagent materials)and normal con-tinuous alkylation using industrial paraffin and olefins materials were examined.Even under the relatively hype-critical reaction conditions,the single pass conversion of pure 1-dodecene could reach to nearly 100.0%,and the selectivity of 2-phenyl isomer was higher than 37.7%.Although the positions along the reactor for sidetrack feeding were different,the 100.0%single pass conversion of 1-dodecene was also attained before the outlet of the reactor.The refined industrial olefins as raw material could meet with the requirements of continuous alkyla-tion.The influences of impurities such as di-olefins and non-benzene aromatics on the catalytic activity and stability should be studied further.

Benzene alkylation with long chain olefins catalyzed by ionic liquids:a review

The introduction of ionic liquids to alkylation process gives a choice for“green production”in the petrochemical and detergent industry.A lot of papers and patents have been published using chloroaluminate ionic liquid as a novel catalyst for alkylation with high reactivity and easy separation from reactants.These included the acidity,characterization,determination and catalysis technologies in batch and continuous operation mode for different scales.According to published data and several results of pilot alkylation,including the authors’experience,the prospect of chloroaluminate ionic liquids for commercials was also discussed.It has been pointed out that there still are many difficulties and challenges to be overcome for commercial application of the ionic liquid catalyst.