The aim of this paper is to study the effect of agitator’s types on the turbulent flows in stirred tanks without and with baffles.The hydrodynamics behavior induced by four different agitator’s types:a Rushton turbi...The aim of this paper is to study the effect of agitator’s types on the turbulent flows in stirred tanks without and with baffles.The hydrodynamics behavior induced by four different agitator’s types:a Rushton turbine(RT),a circular blade turbine(CBT),a diverging triangular blade turbine(DTBT)and converging triangular blade turbine(CTBT)are numerically predicted by solving the Navier-Stokes equations and RNGκ–εturbulent model.The simulations are carried out using the Multi Reference Frame(MRF)approach.The numerical results showed good agreement with experiment.We find that the agitator CTBT gives an important profit on the power consumption per report/ratio the others and DTBT give a good reduction of the vortex size of the impeller angles.展开更多
This work focuses on drop breakage for liquid-liquid system with an adoption of numerical simulation by using computational fluid dynamics and population balance model (PBM) coupled with two-fluid model (TFM). Two dif...This work focuses on drop breakage for liquid-liquid system with an adoption of numerical simulation by using computational fluid dynamics and population balance model (PBM) coupled with two-fluid model (TFM). Two different breakage kernels based on identical breakage mechanism but different descriptions of breaking time are take n into account in this work. Eight cases corresp on ding to distinct configurations of agitator are carried out to validate numerical predictions, namely agitators with different porosity and hole diameters, respectively implemented in Cases 1 to 5 and Cases 6 to 8. The results are compared with experimental data for testing the applicability of both kernels. Simulations are implemented, in this work, with an approach of class method for the solution of population balance model by the special-purpose computational fluid dynamics solver Fluent 16.1 based on finite volume method, and the grids used for meshing the solution domain are accomplished in a commercial software Gambit 2.4.6. The effects of configurations of agitator corresponding to different parameters mentioned above on final Sauter mean diameter are equally concentrated in this work. Analysis of both kernels and comparisons with experimental results reveal that, the second kernel has more decent agreement with experiments, and the results of investigations on effects of agitator configurations show that the in fluences of these parameters on Sauter mean diameter are marginal, but appropriate porosity and hole diameter are actually able to decrease Sauter mean diameter. These outcomes allow us to draw general conclusions and help investigate performances of liquid-liquid system.展开更多
The multiphase reaction process of pressure leaching is mainly carried out in the liquid phase. Therefore, gas holdup is essential for the gas–liquid–solid phase reaction and the extraction rate of valuable metals. ...The multiphase reaction process of pressure leaching is mainly carried out in the liquid phase. Therefore, gas holdup is essential for the gas–liquid–solid phase reaction and the extraction rate of valuable metals. In this paper, a transparent quartz autoclave, a six blades disc turbine-type agitator, and a high-speed camera were used to investigate the gas holdup of the pressure leaching process. Furthermore, experiments determining the effects of agitation rate, temperature, and oxygen partial pressure on gas holdup were carried out. The results showed that when the agitation rate increased from 350 to 600 r/min, the gas holdup increased from 0.10% to 0.64%. When the temperature increased from 363 to 423 K, the gas holdup increased from 0.14% to 0.20%. When the oxygen partial pressure increased from 0.1 to 0.8 MPa, the gas holdup increased from 0.13% to 0.19%. A similar criteria relationship was established by Homogeneous Principle and Buckingham's theorem. Comprehensively, empirical equation of gas holdup was deduced on the basis of experimental data and the similarity theory, where the criterion equation was determined as ε=4.54×10^(-11)n^(3.65)T^(2.08)P_g^(0.18). It can be seen from the formula that agitation rate made the most important impact on gas holdup in the pressure leaching process using the mixed-flow agitator.展开更多
The reactor is equipped with two different types of agitators: the diameter-variable agitator and the two-pitched-paddle agitator. The diameter of the former can be varied according to the requirement of the chemical ...The reactor is equipped with two different types of agitators: the diameter-variable agitator and the two-pitched-paddle agitator. The diameter of the former can be varied according to the requirement of the chemical reactions, thus making the concentration and temperature of the whole reaction system uniform throughout the reactor without any stagnant zone. It is shown that the apparatus has the preponderance over conventional agitator, especially when extremely rapid reactions are accompanied by large amount of reaction heat and when the viscosity of the reaction system varies in a wide range. The reactor is very effective when applied to the polycondensation reaction between paraphenylene diamine （PPDA） and terephthyl chloride （TPC）. The inherent viscosity (η<sub>inh</sub>) of the polymer comes up to more than 5. This innovative agitator has the advantage of simplicity in structure and flexibility in operation, etc.展开更多
The device that consists of tank and disk agitator for evaluation drag reduction agents(DRA) was established.The effect of DRA was defined by testing the changes of agitator torque that drives the disk rotation.The HG...The device that consists of tank and disk agitator for evaluation drag reduction agents(DRA) was established.The effect of DRA was defined by testing the changes of agitator torque that drives the disk rotation.The HG-DRA for oil pipeline from Linyi to Puyang was studied by agitator tank device.The relationships between the drag reduction rate and Reynolds number,concentration,balance time were studied.The best concentration and the highest Renords number for the best drag reduction rate were confirmed.The results show that the drag reduction rate tested in agitator tank is close to that in pipeline.The maximum error of drag reduction rate between pipeline and agitator tank is 18.3%,which indicates that the agitator tank device is available to evaluate the effect of DRA for pipeline and it also has the advantages of simple,easy to be operated and using small volume of oil.Those are very helpful for operaters to know the properties of DRA and operate pipeline well.展开更多
Agitation is a neuropsychiatric syndrome characterized by excessive motor and/or verbal behaviors,with or without aggressive behaviors.The prevalence of agitation in Alzheimer’s disease varies from 5%to over 50%.Mult...Agitation is a neuropsychiatric syndrome characterized by excessive motor and/or verbal behaviors,with or without aggressive behaviors.The prevalence of agitation in Alzheimer’s disease varies from 5%to over 50%.Multiple factors have been implicated in its pathophysiology,including disease stage,comorbidity with other symptoms(e.g.,psychosis,anxiety/depression),and psychosocial factors.Ruling out delirium and identifying environmental triggers are fundamental steps in the management of agitation in Alzheimer’s disease.For establishing an effective therapeutic plan,it is important to define duration,severity,and potential for harm.While non-pharmacological approaches are considered the first line of intervention,pharmacological agents are frequently used in the treatment of agitation.Antipsychotics are commonly used in acute agitation.For chronic agitation,serotonin-selective reuptake inhibitors,especially citalopram and escitalopram,are often preferred due to safety concerns associated with the longterm use of antipsychotics.Promising novel strategies,such as new compounds and neuromodulation,are likely to be incorporated into agitation therapeutics in the next few years.展开更多
Unintended dural tear(DT)is not an infrequent complication of biportal percutaneous endoscopic spinal surgery(BESS).DT manifests in neurological deficits,including seizure,headache,and intracranial hemorrhage.Meanwhil...Unintended dural tear(DT)is not an infrequent complication of biportal percutaneous endoscopic spinal surgery(BESS).DT manifests in neurological deficits,including seizure,headache,and intracranial hemorrhage.Meanwhile,DT may be a risk of emergence agitation(EA)after BESS,which has not yet been reported.We presented a case of a 55-year-old man with L5-S1 intervertebral disc herniation receiving BESS under general anesthesia.A DT about 3-4 mm occurred during the operation,and was repaired immediately.The patient presented EA shouting for a headache after the surgery in post anesthesia care unit(PACU).Sedative agents(midazolam,propofol and dexmedetomidine)were used,only continuously infusion of dexmedetomidine for about 4 h successfully improved EA in PACU.He had no neurologic deficits in following 3 months.This case report highlights the risk of EA when a DT occurs during BESS.Adequate sedation in early phase is critical to resolve the mass effect caused by EA.展开更多
The agitated thin-film evaporator(ATFE)plays a crucial role in evaporation and concentration processes.The design of the scraper for processing high-viscosity non-Newtonian fluids in the ATFE is complex.The intricate ...The agitated thin-film evaporator(ATFE)plays a crucial role in evaporation and concentration processes.The design of the scraper for processing high-viscosity non-Newtonian fluids in the ATFE is complex.The intricate scraping action of the scraper introduces gas into the liquid film,leading to the formation of a gas ring along the wall.This process subsequently reduces wall heat flow,thereby affecting heat transfer.Computational fluid dynamics(CFD)is used to simulate the flow field of the non-Newtonian fluid in the ATFE.The investigation focuses on understanding the mechanism behind the formation of gas rings in the liquid film and proposes methods to prevent their formation.The results demonstrate a transition of the gas from a gas ring suspended in the liquid to a gas ring attached to the wall after entering the liquid film.The scraping action around the circumference of the scraper helps to expel gas rings,indicating the necessity of adjusting the scraper arrangement and increasing the frequency of scraping to enhance gas ring expulsion.The spiral motion of the bow wave serves as the source of gas entry into the liquid film.Therefore,the rotation speed can appropriately increase to reduce the size of the bow wave,thereby inhibiting the formation of the gas ring from the source.This research investigates the mechanism of gas ring generation and expulsion,offering theoretical guidance for processing high-viscosity non-Newtonian materials in the flow field of the ATFE.展开更多
BACKGROUND General anesthesia is commonly used in the surgical management of gastrointestinal tumors;however,it can lead to emergence agitation(EA).EA is a common complication associated with general anesthesia,often ...BACKGROUND General anesthesia is commonly used in the surgical management of gastrointestinal tumors;however,it can lead to emergence agitation(EA).EA is a common complication associated with general anesthesia,often characterized by behaviors,such as crying,struggling,and involuntary limb movements in patients.If treatment is delayed,there is a risk of incision cracking and bleeding,which can significantly affect surgical outcomes.Therefore,having a proper understanding of the factors influencing the occurrence of EA and implementing early preventive measures may reduce the incidence of agitation during the recovery phase from general anesthesia,which is beneficial for improving patient prognosis.AIM To analyze influencing factors and develop a risk prediction model for EA occurrence following general anesthesia for primary liver cancer.METHODS Retrospective analysis of clinical data from 200 patients who underwent hepatoma resection under general anesthesia at Wenzhou Central Hospital(January 2020 to December 2023)was conducted.Post-surgery,the Richmond Agitation-Sedation Scale was used to evaluate EA presence,noting EA incidence after general anesthesia.Patients were categorized by EA presence postoperatively,and the influencing factors were analyzed using logistic regression.A nomogram-based risk prediction model was constructed and evaluated for differentiation and fit using receiver operating characteristics and calibration curves.RESULTS EA occurred in 51(25.5%)patients.Multivariate analysis identified advanced age,American Society of Anesthesiologists(ASA)grade Ⅲ,indwelling catheter use,and postoperative pain as risk factors for EA(P<0.05).Conversely,postoperative analgesia was a protective factor against EA(P<0.05).The area under the curve of the nomogram was 0.972[95%confidence interval(CI):0.947-0.997]for the training set and 0.979(95%CI:0.951-1.000)for the test set.Hosmer-Lemeshow test showed a good fit(χ^(2)=5.483,P=0.705),and calibration curves showed agreement between predicted and actual EA incidence.CONCLUSION Age,ASA grade,catheter use,postoperative pain,and analgesia significantly influence EA occurrence.A nomogram constructed using these factors demonstrates strong predictive accuracy.展开更多
BACKGROUND Preoperative anxiety is a common emotional problem during the perioperative period and may adversely affect postoperative recovery.Emergence agitation(EA)is a common complication of general anesthesia that ...BACKGROUND Preoperative anxiety is a common emotional problem during the perioperative period and may adversely affect postoperative recovery.Emergence agitation(EA)is a common complication of general anesthesia that may increase patient discomfort and hospital stay and may be associated with the development of postoperative complications.Pre-anesthetic anxiety may be associated with the development of EA,but studies in this area are lacking.AIM To determine the relationship between pre-anesthetic anxiety and EA after radical surgery in patients with non-small cell lung cancer(NSCLC).METHODS Eighty patients with NSCLC undergoing surgical treatment between June 2020 and June 2023 were conveniently sampled.We used the Hospital Anxiety and Depression Scale’s(HADS)anxiety subscale(HADS-A)to determine patients’anxiety at four time points(T1-T4):Patients’preoperative visit,waiting period in the surgical waiting room,after entering the operating room,and before anesthesia induction,respectively.The Riker Sedation-Agitation Scale(RSAS)examined EA after surgery.Scatter plots of HADS-A and RSAS scores assessed the correlation between patients’pre-anesthesia anxiety status and EA.We performed a partial correlation analysis of HADS-A scores with RSAS scores.RESULTS NSCLC patients’HADS-A scores gradually increased at the four time points:7.33±2.03 at T1,7.99±2.22 at T2,8.05±2.81 at T3,and 8.36±4.17 at T4.The patients’postoperative RSAS score was 4.49±1.18,and 27 patients scored≥5,indicating that 33.75%patients had EA.HADS-A scores at T3 and T4 were significantly higher in patients with EA(9.67±3.02 vs 7.23±2.31,12.56±4.10 vs 6.23±2.05,P<0.001).Scatter plots showed the highest correlation between HADS-A and RSAS scores at T3 and T4.Partial correlation analysis showed a strong positive correlation between HADS-A and RSAS scores at T3 and T4(r=0.296,0.314,P<0.01).CONCLUSION Agitation during anesthesia recovery in patients undergoing radical resection for NSCLC correlated with anxiety at the time of entering the operating room and before anesthesia induction.展开更多
BACKGROUND Laparoscopic hernia repair is a minimally invasive surgery,but patients may experience emergence agitation(EA)during the post-anesthesia recovery period,which can increase pain and lead to complications suc...BACKGROUND Laparoscopic hernia repair is a minimally invasive surgery,but patients may experience emergence agitation(EA)during the post-anesthesia recovery period,which can increase pain and lead to complications such as wound reopening and bleeding.There is limited research on the risk factors for this agitation,and few effective tools exist to predict it.Therefore,by integrating clinical data,we have developed nomograms and random forest predictive models to help clinicians predict and potentially prevent EA.AIM To establish a risk nomogram prediction model for EA in patients undergoing laparoscopic hernia surgery under total inhalation combined with sacral block anesthesia.METHODS Based on the clinical information of 300 patients who underwent laparoscopic hernia surgery in the Nanning Tenth People’s Hospital,Guangxi,from January 2020 to June 2023,the patients were divided into two groups according to their sedation-agitation scale score,i.e.,the EA group(≥5 points)and the non-EA group(≤4 points),during anesthesia recovery.Least absolute shrinkage and selection operator regression was used to select the key features that predict EA,and incorporating them into logistic regression analysis to obtain potential pre-dictive factors and establish EA nomogram and random forest risk prediction models through R software.RESULTS Out of the 300 patients,72 had agitation during anesthesia recovery,with an incidence of 24.0%.American Society of Anesthesiologists classification,preoperative anxiety,solid food fasting time,clear liquid fasting time,indwelling catheter,and pain level upon awakening are key predictors of EA in patients undergoing laparoscopic hernia surgery with total intravenous anesthesia and caudal block anesthesia.The nomogram predicts EA with an area under the receiver operating characteristic curve(AUC)of 0.947,a sensi-tivity of 0.917,and a specificity of 0.877,whereas the random forest model has an AUC of 0.923,a sensitivity of 0.912,and a specificity of 0.877.Delong’s test shows no significant difference in AUC between the two models.Clinical decision curve analysis indicates that both models have good net benefits in predicting EA,with the nomogram effective within the threshold of 0.02 to 0.96 and the random forest model within 0.03 to 0.90.In the external model validation of 50 cases of laparoscopic hernia surgery,both models predicted EA.The nomogram model had a sensitivity of 83.33%,specificity of 86.84%,and accuracy of 86.00%,while the random forest model had a sensitivity of 75.00%,specificity of 78.95%,and accuracy of 78.00%,suggesting that the nomogram model performs better in predicting EA.CONCLUSION Independent predictors of EA in patients undergoing laparoscopic hernia repair with total intravenous anesthesia combined with caudal block include American Society of Anesthesiologists classification,preoperative anxiety,duration of solid food fasting,duration of clear liquid fasting,presence of an indwelling catheter,and pain level upon waking.The nomogram and random forest models based on these factors can help tailor clinical decisions in the future.展开更多
BACKGROUND:Agitation is a common presentation within emergent departments(EDs).Agitation during pregnancy should be treated as an obstetric emergency,as the distress may jeopardize both the patient and fetus.The safet...BACKGROUND:Agitation is a common presentation within emergent departments(EDs).Agitation during pregnancy should be treated as an obstetric emergency,as the distress may jeopardize both the patient and fetus.The safety of psychotropic medications in the reproductive age female has not been well established.This review aimed to explore a summary of general agitation recommendations with an emphasis on ED management of agitation during pregnancy.METHODS:A literature review was conducted to explore the pathophysiology of acute agitation and devise a preferred treatment plan for ED management of acute agitation in the reproductive age or pregnant female.RESULTS:While nonpharmacological management is preferred,ED visits for agitation often require medical management.Medication should be selected based on the etiology of agitation and the clinical setting to avoid major adverse effects.Adverse effects are common in pregnant females.For mild to moderate agitation in pregnancy,diphenhydramine is an effective sedating agent with minimal adverse effects.In moderate to severe agitation,high-potency typical psychotropics are preferred due to their neutral effects on hemodynamics.Haloperidol has become the most frequently utilized psychotropic for agitation during pregnancy.Second generation psychotropics are often utilized as second-line therapy,including risperidone.Benzodiazepines and ketamine have demonstrated adverse fetal outcomes.CONCLUSION:While randomized control studies cannot be ethically conducted on pregnant patients requiring sedation,animal models and epidemiologic studies have demonstrated the effects of psychotropic medication exposure in utero.As the fetal risk associated with multiple doses of psychotropic medications remains unknown,weighing the risks and benefits of each agent,while utilizing the lowest effective dose remains critical in the treatment of acute agitation within the EDs.展开更多
Tannin foam is a new functional material.It can be widely applied to the automobile industry,construction industry,and packaging industry due to its wide range of raw materials,renewable,easily degraded,low cost and a...Tannin foam is a new functional material.It can be widely applied to the automobile industry,construction industry,and packaging industry due to its wide range of raw materials,renewable,easily degraded,low cost and almost no pollution.Preparing tannin foam is a very complex process that includes high temperature,two phases,mechanical agitation,and phase change.To investigate the influence of the stirring velocity and paddle shape,simulation was calculated by making use of the volume of fluid(VOF)method and multiple reference frame(MRF)method in a three-dimensional flow field of tannin-based foaming precursor resin.The gas holdup and velocity magnitude were analysed with various conditions of mechanical velocities and paddle shape in the stirring flow field.The result shows the higher the velocity,the greater the disturbance and paddle shape between the eggbeater and the Rushton turbine,obviously the paddle shape of the eggbeater with a wider range of agitation,which can entrap more air into the tannin-based foaming precursor resin in a short time.Especially when the speed is 1500 rpm,the flow field of the Rushton turbine comes out of a ditch,which decreases the efficiency of mass transfer;there is less air to mix into the tannin-based foaming precursor resin,which causes unevenness.At the same time,the eggbeater shows the marvelous capability of hybrid as it has two vortexes and multiple cycles that make a difference from the Rushton turbine,which has only one vortex and two upper and lower loops;the structure makes the flow field more stable allowed evenness of flow field tannin-based foaming precursor resin.The results reveal that it is beneficial for tannin-based foaming precursor resin to use an eggbeater with a speed of 1500 rpm to reduce the consumption of resources while obtaining a uniform flow field.展开更多
Background: Emergence agitation (EA) is a common phenomenon observed in pediatric patients following general anesthesia. This study aimed to assess the efficacy of propofol and fentanyl in preventing EA and to compare...Background: Emergence agitation (EA) is a common phenomenon observed in pediatric patients following general anesthesia. This study aimed to assess the efficacy of propofol and fentanyl in preventing EA and to compare their associated complications or side effects. Methods: This prospective randomized observational comparative study was conducted at Dhaka Medical College Hospital from July 2013 to June 2014. The study aimed to evaluate the effects of propofol and fentanyl on EA in children aged 18 to 72 months undergoing circumcision, herniotomy, and polypectomy operations. Ninety children were included in the study, with 45 in each group. Patients with psychological or neurological disorders were excluded. Various parameters including age, sex, weight, American Society of Anesthesiologists (ASA) class, duration of anesthesia, Saturation of Peripheral Oxygen (SPO2), heart rate (HR), respiratory rate (RR), Pediatric Anesthesia Emergence Delirium (PAED) score, duration of post-anesthesia care unit (PACU) stay, incidence of laryngospasm, nausea, vomiting, and rescue drug requirement were compared between the two groups. Results: Age, sex, weight, ASA class, and duration of anesthesia were comparable between the two groups. Perioperative SpO2 and HR were similar in both groups. However, the PAED score was significantly higher in the fentanyl group during all follow-ups except at 30 minutes postoperatively. The mean duration of PACU stay was significantly longer in the fentanyl group. Although the incidence of laryngospasm was higher in the fentanyl group, it was not statistically significant. Conversely, nausea or vomiting was significantly higher in the fentanyl group. The requirement for rescue drugs was significantly higher in the fentanyl group compared to the propofol group. Conclusion: Both propofol and fentanyl were effective in preventing emergence agitation in pediatric patients undergoing various surgical procedures under sevoflurane anesthesia. However, propofol demonstrated a better safety profile with fewer incidences of nausea, vomiting, and rescue drug requirements compared to fentanyl.展开更多
A laboratory-scale reaction-crystallization process of struvite synthesis from diluted water solution of Mg^2＋, NH^＋ 4 and PO3- ions was studied. The research covered the tests of two original constructions of conti...A laboratory-scale reaction-crystallization process of struvite synthesis from diluted water solution of Mg^2＋, NH^＋ 4 and PO3- ions was studied. The research covered the tests of two original constructions of continuous jet-pump Draft Tube Magma （DTM）-type crystallizers with internal circulation of suspension （upward/downward）. Interactions between constructional, hydrodynamic and kinetic factors were established and discussed. Nucleation and linear growth rates of struvite crystals were calculated on the basis of population density distribution. Kinetic model of idealized Mixed Suspension Mixed Product Removal （MSMPR） crystallizer considering the size-dependent growth mechanism was applied （Rojkowski hyperbolic equation）. For comparison purposes the kinetic data corre- sponded to a simpler, continuous draft tube-type crystallizer equipped with propeller agitator were analyzed. It was concluded that crystal product of larger size was withdrawn from the jet-pump DTM crystallizer of the descending flow of suspension in a mixing chamber.展开更多
In accordance to the anisotropic feature of turbulent flow, ananisotropic algebraic stress model is adopted to predict theturbulent flow field and turbulent characteristics generated by aRushton disc turbine with the ...In accordance to the anisotropic feature of turbulent flow, ananisotropic algebraic stress model is adopted to predict theturbulent flow field and turbulent characteristics generated by aRushton disc turbine with the improved inner-outer iterativeprocedure. The predicted turbulent flow is compared with experimentaldata and the simulation by the standard k-ε turbulence model. Theanisotropic algebraic stress model is found to give better predictionthan the standard k-ε turbulence model. The predicted turbulent flowfield is in accordance to experimental data and the trend of theturbulence intensity can be effectively reflected in the simulation.展开更多
The spatial structure of the velocity field in a stirred vessel with water has been measured and analyzed using the laser Doppler velocimeter technique, with the immersing depth and agitation speed of the impeller re-...The spatial structure of the velocity field in a stirred vessel with water has been measured and analyzed using the laser Doppler velocimeter technique, with the immersing depth and agitation speed of the impeller re-maining approximately constant. The experimental results were provided such as the mean velocity field, fluctuat-ing velocities, turbulent kinetic energy, Reynolds shear stress and time series of the velocity in the stirred tank. These results probably provided the valuable basis to further optimize and enlarge the stirred tank in the industrial process.展开更多
AIM To evaluate the safety and efficacy of agitation thrombolysis(AT) combined with catheter-directed thrombolysis(CDT) for the treatment of non-cirrhotic acute portal vein thrombosis(PVT). METHODS Nine patients with ...AIM To evaluate the safety and efficacy of agitation thrombolysis(AT) combined with catheter-directed thrombolysis(CDT) for the treatment of non-cirrhotic acute portal vein thrombosis(PVT). METHODS Nine patients with non-cirrhotic acute PVT who underwent AT combined with CDT were analyzed retrospectively. Portography was carried out via the transjugular intrahepatic portosystemic(commonly known as TIP) or percutaneous transhepatic(commonly known as PT) route, followed by AT combined with CDT. Complications of the procedure, and the changes in clinical symptoms, hemodynamics of the portal vein and liver function were recorded. Follow-up was scheduled at1, 3 and 6 mo after treatment, and every 6 mo thereafter, or when the patients developed clinical symptoms related to PVT. Color Doppler ultrasound and contrast-enhanced computed tomography/magnetic resonance imaging were performed during the follow-up period to determine the condition of the portal vein.RESULTS AT combined with CDT was successfully performed. The portal vein was reached via the TIP route in 6 patients, and via the PT route in 3 patients. All clinical symptoms were relieved or disappeared, with the exception of 1 patient who died of intestinal necrosis 9 d after treatment. Significant differences in the changes in portal vein hemodynamics were observed, including the maximum lumen occupancy of PVT, portal vein pressure and flow velocity between pre-and posttreatment(P < 0.05). During the follow-up period, recurrence was observed in 1 patient at 19 mo after the procedure, and the portal vein was patent in the remaining patients.CONCLUSION AT combined with CDT is a safe and effective method for the treatment of non-cirrhotic acute PVT.展开更多
Pneumatically agitated slurry reactors,including bubble column reactors and airlift loop reactors(ALRs),are important gas-liquid-solid multiphase reactors.These reactors have been widely applied in many processes,espe...Pneumatically agitated slurry reactors,including bubble column reactors and airlift loop reactors(ALRs),are important gas-liquid-solid multiphase reactors.These reactors have been widely applied in many processes,especially in the biological fermentation and energy chemical industry,due to their low shear stress,good mixing,perfect mass-/heat-transfer properties,and relatively low costs.To further improve the performance of slurry reactors(i.e.,mixing and mass/heat transfer)and to satisfy industrial require-ments(e.g.,temperature control,reduction of back-mixing,and product separation),the process intensi-fication of slurry reactors is essential.This article starts by reviewing the latest advancements in the intensification of mixing and mass/heat transfer in these two types of reactors.It then summarizes process-intensification methods for mixing and separation that allow continuous production in these slurry reactors.Process-intensification technology that integrates directional flow in an ALR with simple solid-liquid separation in a hydrocyclone is recommended for its high efficiency and low costs.This arti-cle also systematically addresses vital considerations and challenges,including flow regime discrimina-tion,gas spargers,solid particle effects,and other concerns in slurry reactors.It introduces the progress of numerical simulation using computational fluid dynamics(CFD)for the rational design of slurry reactors and discusses difficulties in modeling.Finally,it presents conclusions and perspectives on the design of industrial slurry reactors.展开更多
文摘The aim of this paper is to study the effect of agitator’s types on the turbulent flows in stirred tanks without and with baffles.The hydrodynamics behavior induced by four different agitator’s types:a Rushton turbine(RT),a circular blade turbine(CBT),a diverging triangular blade turbine(DTBT)and converging triangular blade turbine(CTBT)are numerically predicted by solving the Navier-Stokes equations and RNGκ–εturbulent model.The simulations are carried out using the Multi Reference Frame(MRF)approach.The numerical results showed good agreement with experiment.We find that the agitator CTBT gives an important profit on the power consumption per report/ratio the others and DTBT give a good reduction of the vortex size of the impeller angles.
基金Supported by the National Natural Science Foundation of China(21776180,21306116)
文摘This work focuses on drop breakage for liquid-liquid system with an adoption of numerical simulation by using computational fluid dynamics and population balance model (PBM) coupled with two-fluid model (TFM). Two different breakage kernels based on identical breakage mechanism but different descriptions of breaking time are take n into account in this work. Eight cases corresp on ding to distinct configurations of agitator are carried out to validate numerical predictions, namely agitators with different porosity and hole diameters, respectively implemented in Cases 1 to 5 and Cases 6 to 8. The results are compared with experimental data for testing the applicability of both kernels. Simulations are implemented, in this work, with an approach of class method for the solution of population balance model by the special-purpose computational fluid dynamics solver Fluent 16.1 based on finite volume method, and the grids used for meshing the solution domain are accomplished in a commercial software Gambit 2.4.6. The effects of configurations of agitator corresponding to different parameters mentioned above on final Sauter mean diameter are equally concentrated in this work. Analysis of both kernels and comparisons with experimental results reveal that, the second kernel has more decent agreement with experiments, and the results of investigations on effects of agitator configurations show that the in fluences of these parameters on Sauter mean diameter are marginal, but appropriate porosity and hole diameter are actually able to decrease Sauter mean diameter. These outcomes allow us to draw general conclusions and help investigate performances of liquid-liquid system.
基金financially supported by the Joint Funds of the National Natural Science Foundation of China (Nos.U1402271, 51504058, and 51504059)
文摘The multiphase reaction process of pressure leaching is mainly carried out in the liquid phase. Therefore, gas holdup is essential for the gas–liquid–solid phase reaction and the extraction rate of valuable metals. In this paper, a transparent quartz autoclave, a six blades disc turbine-type agitator, and a high-speed camera were used to investigate the gas holdup of the pressure leaching process. Furthermore, experiments determining the effects of agitation rate, temperature, and oxygen partial pressure on gas holdup were carried out. The results showed that when the agitation rate increased from 350 to 600 r/min, the gas holdup increased from 0.10% to 0.64%. When the temperature increased from 363 to 423 K, the gas holdup increased from 0.14% to 0.20%. When the oxygen partial pressure increased from 0.1 to 0.8 MPa, the gas holdup increased from 0.13% to 0.19%. A similar criteria relationship was established by Homogeneous Principle and Buckingham's theorem. Comprehensively, empirical equation of gas holdup was deduced on the basis of experimental data and the similarity theory, where the criterion equation was determined as ε=4.54×10^(-11)n^(3.65)T^(2.08)P_g^(0.18). It can be seen from the formula that agitation rate made the most important impact on gas holdup in the pressure leaching process using the mixed-flow agitator.
文摘The reactor is equipped with two different types of agitators: the diameter-variable agitator and the two-pitched-paddle agitator. The diameter of the former can be varied according to the requirement of the chemical reactions, thus making the concentration and temperature of the whole reaction system uniform throughout the reactor without any stagnant zone. It is shown that the apparatus has the preponderance over conventional agitator, especially when extremely rapid reactions are accompanied by large amount of reaction heat and when the viscosity of the reaction system varies in a wide range. The reactor is very effective when applied to the polycondensation reaction between paraphenylene diamine （PPDA） and terephthyl chloride （TPC）. The inherent viscosity (η<sub>inh</sub>) of the polymer comes up to more than 5. This innovative agitator has the advantage of simplicity in structure and flexibility in operation, etc.
文摘The device that consists of tank and disk agitator for evaluation drag reduction agents(DRA) was established.The effect of DRA was defined by testing the changes of agitator torque that drives the disk rotation.The HG-DRA for oil pipeline from Linyi to Puyang was studied by agitator tank device.The relationships between the drag reduction rate and Reynolds number,concentration,balance time were studied.The best concentration and the highest Renords number for the best drag reduction rate were confirmed.The results show that the drag reduction rate tested in agitator tank is close to that in pipeline.The maximum error of drag reduction rate between pipeline and agitator tank is 18.3%,which indicates that the agitator tank device is available to evaluate the effect of DRA for pipeline and it also has the advantages of simple,easy to be operated and using small volume of oil.Those are very helpful for operaters to know the properties of DRA and operate pipeline well.
基金Supported by the National Institutes of Health/National Institute on Aging,No.1R21AG091282.
文摘Agitation is a neuropsychiatric syndrome characterized by excessive motor and/or verbal behaviors,with or without aggressive behaviors.The prevalence of agitation in Alzheimer’s disease varies from 5%to over 50%.Multiple factors have been implicated in its pathophysiology,including disease stage,comorbidity with other symptoms(e.g.,psychosis,anxiety/depression),and psychosocial factors.Ruling out delirium and identifying environmental triggers are fundamental steps in the management of agitation in Alzheimer’s disease.For establishing an effective therapeutic plan,it is important to define duration,severity,and potential for harm.While non-pharmacological approaches are considered the first line of intervention,pharmacological agents are frequently used in the treatment of agitation.Antipsychotics are commonly used in acute agitation.For chronic agitation,serotonin-selective reuptake inhibitors,especially citalopram and escitalopram,are often preferred due to safety concerns associated with the longterm use of antipsychotics.Promising novel strategies,such as new compounds and neuromodulation,are likely to be incorporated into agitation therapeutics in the next few years.
文摘Unintended dural tear(DT)is not an infrequent complication of biportal percutaneous endoscopic spinal surgery(BESS).DT manifests in neurological deficits,including seizure,headache,and intracranial hemorrhage.Meanwhile,DT may be a risk of emergence agitation(EA)after BESS,which has not yet been reported.We presented a case of a 55-year-old man with L5-S1 intervertebral disc herniation receiving BESS under general anesthesia.A DT about 3-4 mm occurred during the operation,and was repaired immediately.The patient presented EA shouting for a headache after the surgery in post anesthesia care unit(PACU).Sedative agents(midazolam,propofol and dexmedetomidine)were used,only continuously infusion of dexmedetomidine for about 4 h successfully improved EA in PACU.He had no neurologic deficits in following 3 months.This case report highlights the risk of EA when a DT occurs during BESS.Adequate sedation in early phase is critical to resolve the mass effect caused by EA.
基金National Natural Science Foundation of China(No.51905089)Fundamental Research Funds for the Central Universities,China(No.2232020D-31)。
文摘The agitated thin-film evaporator(ATFE)plays a crucial role in evaporation and concentration processes.The design of the scraper for processing high-viscosity non-Newtonian fluids in the ATFE is complex.The intricate scraping action of the scraper introduces gas into the liquid film,leading to the formation of a gas ring along the wall.This process subsequently reduces wall heat flow,thereby affecting heat transfer.Computational fluid dynamics(CFD)is used to simulate the flow field of the non-Newtonian fluid in the ATFE.The investigation focuses on understanding the mechanism behind the formation of gas rings in the liquid film and proposes methods to prevent their formation.The results demonstrate a transition of the gas from a gas ring suspended in the liquid to a gas ring attached to the wall after entering the liquid film.The scraping action around the circumference of the scraper helps to expel gas rings,indicating the necessity of adjusting the scraper arrangement and increasing the frequency of scraping to enhance gas ring expulsion.The spiral motion of the bow wave serves as the source of gas entry into the liquid film.Therefore,the rotation speed can appropriately increase to reduce the size of the bow wave,thereby inhibiting the formation of the gas ring from the source.This research investigates the mechanism of gas ring generation and expulsion,offering theoretical guidance for processing high-viscosity non-Newtonian materials in the flow field of the ATFE.
文摘BACKGROUND General anesthesia is commonly used in the surgical management of gastrointestinal tumors;however,it can lead to emergence agitation(EA).EA is a common complication associated with general anesthesia,often characterized by behaviors,such as crying,struggling,and involuntary limb movements in patients.If treatment is delayed,there is a risk of incision cracking and bleeding,which can significantly affect surgical outcomes.Therefore,having a proper understanding of the factors influencing the occurrence of EA and implementing early preventive measures may reduce the incidence of agitation during the recovery phase from general anesthesia,which is beneficial for improving patient prognosis.AIM To analyze influencing factors and develop a risk prediction model for EA occurrence following general anesthesia for primary liver cancer.METHODS Retrospective analysis of clinical data from 200 patients who underwent hepatoma resection under general anesthesia at Wenzhou Central Hospital(January 2020 to December 2023)was conducted.Post-surgery,the Richmond Agitation-Sedation Scale was used to evaluate EA presence,noting EA incidence after general anesthesia.Patients were categorized by EA presence postoperatively,and the influencing factors were analyzed using logistic regression.A nomogram-based risk prediction model was constructed and evaluated for differentiation and fit using receiver operating characteristics and calibration curves.RESULTS EA occurred in 51(25.5%)patients.Multivariate analysis identified advanced age,American Society of Anesthesiologists(ASA)grade Ⅲ,indwelling catheter use,and postoperative pain as risk factors for EA(P<0.05).Conversely,postoperative analgesia was a protective factor against EA(P<0.05).The area under the curve of the nomogram was 0.972[95%confidence interval(CI):0.947-0.997]for the training set and 0.979(95%CI:0.951-1.000)for the test set.Hosmer-Lemeshow test showed a good fit(χ^(2)=5.483,P=0.705),and calibration curves showed agreement between predicted and actual EA incidence.CONCLUSION Age,ASA grade,catheter use,postoperative pain,and analgesia significantly influence EA occurrence.A nomogram constructed using these factors demonstrates strong predictive accuracy.
文摘BACKGROUND Preoperative anxiety is a common emotional problem during the perioperative period and may adversely affect postoperative recovery.Emergence agitation(EA)is a common complication of general anesthesia that may increase patient discomfort and hospital stay and may be associated with the development of postoperative complications.Pre-anesthetic anxiety may be associated with the development of EA,but studies in this area are lacking.AIM To determine the relationship between pre-anesthetic anxiety and EA after radical surgery in patients with non-small cell lung cancer(NSCLC).METHODS Eighty patients with NSCLC undergoing surgical treatment between June 2020 and June 2023 were conveniently sampled.We used the Hospital Anxiety and Depression Scale’s(HADS)anxiety subscale(HADS-A)to determine patients’anxiety at four time points(T1-T4):Patients’preoperative visit,waiting period in the surgical waiting room,after entering the operating room,and before anesthesia induction,respectively.The Riker Sedation-Agitation Scale(RSAS)examined EA after surgery.Scatter plots of HADS-A and RSAS scores assessed the correlation between patients’pre-anesthesia anxiety status and EA.We performed a partial correlation analysis of HADS-A scores with RSAS scores.RESULTS NSCLC patients’HADS-A scores gradually increased at the four time points:7.33±2.03 at T1,7.99±2.22 at T2,8.05±2.81 at T3,and 8.36±4.17 at T4.The patients’postoperative RSAS score was 4.49±1.18,and 27 patients scored≥5,indicating that 33.75%patients had EA.HADS-A scores at T3 and T4 were significantly higher in patients with EA(9.67±3.02 vs 7.23±2.31,12.56±4.10 vs 6.23±2.05,P<0.001).Scatter plots showed the highest correlation between HADS-A and RSAS scores at T3 and T4.Partial correlation analysis showed a strong positive correlation between HADS-A and RSAS scores at T3 and T4(r=0.296,0.314,P<0.01).CONCLUSION Agitation during anesthesia recovery in patients undergoing radical resection for NSCLC correlated with anxiety at the time of entering the operating room and before anesthesia induction.
文摘BACKGROUND Laparoscopic hernia repair is a minimally invasive surgery,but patients may experience emergence agitation(EA)during the post-anesthesia recovery period,which can increase pain and lead to complications such as wound reopening and bleeding.There is limited research on the risk factors for this agitation,and few effective tools exist to predict it.Therefore,by integrating clinical data,we have developed nomograms and random forest predictive models to help clinicians predict and potentially prevent EA.AIM To establish a risk nomogram prediction model for EA in patients undergoing laparoscopic hernia surgery under total inhalation combined with sacral block anesthesia.METHODS Based on the clinical information of 300 patients who underwent laparoscopic hernia surgery in the Nanning Tenth People’s Hospital,Guangxi,from January 2020 to June 2023,the patients were divided into two groups according to their sedation-agitation scale score,i.e.,the EA group(≥5 points)and the non-EA group(≤4 points),during anesthesia recovery.Least absolute shrinkage and selection operator regression was used to select the key features that predict EA,and incorporating them into logistic regression analysis to obtain potential pre-dictive factors and establish EA nomogram and random forest risk prediction models through R software.RESULTS Out of the 300 patients,72 had agitation during anesthesia recovery,with an incidence of 24.0%.American Society of Anesthesiologists classification,preoperative anxiety,solid food fasting time,clear liquid fasting time,indwelling catheter,and pain level upon awakening are key predictors of EA in patients undergoing laparoscopic hernia surgery with total intravenous anesthesia and caudal block anesthesia.The nomogram predicts EA with an area under the receiver operating characteristic curve(AUC)of 0.947,a sensi-tivity of 0.917,and a specificity of 0.877,whereas the random forest model has an AUC of 0.923,a sensitivity of 0.912,and a specificity of 0.877.Delong’s test shows no significant difference in AUC between the two models.Clinical decision curve analysis indicates that both models have good net benefits in predicting EA,with the nomogram effective within the threshold of 0.02 to 0.96 and the random forest model within 0.03 to 0.90.In the external model validation of 50 cases of laparoscopic hernia surgery,both models predicted EA.The nomogram model had a sensitivity of 83.33%,specificity of 86.84%,and accuracy of 86.00%,while the random forest model had a sensitivity of 75.00%,specificity of 78.95%,and accuracy of 78.00%,suggesting that the nomogram model performs better in predicting EA.CONCLUSION Independent predictors of EA in patients undergoing laparoscopic hernia repair with total intravenous anesthesia combined with caudal block include American Society of Anesthesiologists classification,preoperative anxiety,duration of solid food fasting,duration of clear liquid fasting,presence of an indwelling catheter,and pain level upon waking.The nomogram and random forest models based on these factors can help tailor clinical decisions in the future.
文摘BACKGROUND:Agitation is a common presentation within emergent departments(EDs).Agitation during pregnancy should be treated as an obstetric emergency,as the distress may jeopardize both the patient and fetus.The safety of psychotropic medications in the reproductive age female has not been well established.This review aimed to explore a summary of general agitation recommendations with an emphasis on ED management of agitation during pregnancy.METHODS:A literature review was conducted to explore the pathophysiology of acute agitation and devise a preferred treatment plan for ED management of acute agitation in the reproductive age or pregnant female.RESULTS:While nonpharmacological management is preferred,ED visits for agitation often require medical management.Medication should be selected based on the etiology of agitation and the clinical setting to avoid major adverse effects.Adverse effects are common in pregnant females.For mild to moderate agitation in pregnancy,diphenhydramine is an effective sedating agent with minimal adverse effects.In moderate to severe agitation,high-potency typical psychotropics are preferred due to their neutral effects on hemodynamics.Haloperidol has become the most frequently utilized psychotropic for agitation during pregnancy.Second generation psychotropics are often utilized as second-line therapy,including risperidone.Benzodiazepines and ketamine have demonstrated adverse fetal outcomes.CONCLUSION:While randomized control studies cannot be ethically conducted on pregnant patients requiring sedation,animal models and epidemiologic studies have demonstrated the effects of psychotropic medication exposure in utero.As the fetal risk associated with multiple doses of psychotropic medications remains unknown,weighing the risks and benefits of each agent,while utilizing the lowest effective dose remains critical in the treatment of acute agitation within the EDs.
基金supported by the Key Program of Applied and Basic Research in Yunnan Province(Grant No.202101AS070008)the National Natural Science Foundation of China(NSFC 31760187)+4 种基金supported by the 111 Project(D21027)the Yunnan Provincial Academician Workstation(YSZJGZZ-2020052)the Foreign Expert Workstation(202305AF150006)supported by the Scientific Research Foundation of Education Department of Yunnan Province(Grant Nos.2023J0696,2023Y0699)Foreign Talent Introduction Program of Science and Technology Department of Yunnan Province(Grant No.202305AO350002).
文摘Tannin foam is a new functional material.It can be widely applied to the automobile industry,construction industry,and packaging industry due to its wide range of raw materials,renewable,easily degraded,low cost and almost no pollution.Preparing tannin foam is a very complex process that includes high temperature,two phases,mechanical agitation,and phase change.To investigate the influence of the stirring velocity and paddle shape,simulation was calculated by making use of the volume of fluid(VOF)method and multiple reference frame(MRF)method in a three-dimensional flow field of tannin-based foaming precursor resin.The gas holdup and velocity magnitude were analysed with various conditions of mechanical velocities and paddle shape in the stirring flow field.The result shows the higher the velocity,the greater the disturbance and paddle shape between the eggbeater and the Rushton turbine,obviously the paddle shape of the eggbeater with a wider range of agitation,which can entrap more air into the tannin-based foaming precursor resin in a short time.Especially when the speed is 1500 rpm,the flow field of the Rushton turbine comes out of a ditch,which decreases the efficiency of mass transfer;there is less air to mix into the tannin-based foaming precursor resin,which causes unevenness.At the same time,the eggbeater shows the marvelous capability of hybrid as it has two vortexes and multiple cycles that make a difference from the Rushton turbine,which has only one vortex and two upper and lower loops;the structure makes the flow field more stable allowed evenness of flow field tannin-based foaming precursor resin.The results reveal that it is beneficial for tannin-based foaming precursor resin to use an eggbeater with a speed of 1500 rpm to reduce the consumption of resources while obtaining a uniform flow field.
文摘Background: Emergence agitation (EA) is a common phenomenon observed in pediatric patients following general anesthesia. This study aimed to assess the efficacy of propofol and fentanyl in preventing EA and to compare their associated complications or side effects. Methods: This prospective randomized observational comparative study was conducted at Dhaka Medical College Hospital from July 2013 to June 2014. The study aimed to evaluate the effects of propofol and fentanyl on EA in children aged 18 to 72 months undergoing circumcision, herniotomy, and polypectomy operations. Ninety children were included in the study, with 45 in each group. Patients with psychological or neurological disorders were excluded. Various parameters including age, sex, weight, American Society of Anesthesiologists (ASA) class, duration of anesthesia, Saturation of Peripheral Oxygen (SPO2), heart rate (HR), respiratory rate (RR), Pediatric Anesthesia Emergence Delirium (PAED) score, duration of post-anesthesia care unit (PACU) stay, incidence of laryngospasm, nausea, vomiting, and rescue drug requirement were compared between the two groups. Results: Age, sex, weight, ASA class, and duration of anesthesia were comparable between the two groups. Perioperative SpO2 and HR were similar in both groups. However, the PAED score was significantly higher in the fentanyl group during all follow-ups except at 30 minutes postoperatively. The mean duration of PACU stay was significantly longer in the fentanyl group. Although the incidence of laryngospasm was higher in the fentanyl group, it was not statistically significant. Conversely, nausea or vomiting was significantly higher in the fentanyl group. The requirement for rescue drugs was significantly higher in the fentanyl group compared to the propofol group. Conclusion: Both propofol and fentanyl were effective in preventing emergence agitation in pediatric patients undergoing various surgical procedures under sevoflurane anesthesia. However, propofol demonstrated a better safety profile with fewer incidences of nausea, vomiting, and rescue drug requirements compared to fentanyl.
文摘A laboratory-scale reaction-crystallization process of struvite synthesis from diluted water solution of Mg^2＋, NH^＋ 4 and PO3- ions was studied. The research covered the tests of two original constructions of continuous jet-pump Draft Tube Magma （DTM）-type crystallizers with internal circulation of suspension （upward/downward）. Interactions between constructional, hydrodynamic and kinetic factors were established and discussed. Nucleation and linear growth rates of struvite crystals were calculated on the basis of population density distribution. Kinetic model of idealized Mixed Suspension Mixed Product Removal （MSMPR） crystallizer considering the size-dependent growth mechanism was applied （Rojkowski hyperbolic equation）. For comparison purposes the kinetic data corre- sponded to a simpler, continuous draft tube-type crystallizer equipped with propeller agitator were analyzed. It was concluded that crystal product of larger size was withdrawn from the jet-pump DTM crystallizer of the descending flow of suspension in a mixing chamber.
基金the National Natural Science Foundation of China (No. 29792074).
文摘In accordance to the anisotropic feature of turbulent flow, ananisotropic algebraic stress model is adopted to predict theturbulent flow field and turbulent characteristics generated by aRushton disc turbine with the improved inner-outer iterativeprocedure. The predicted turbulent flow is compared with experimentaldata and the simulation by the standard k-ε turbulence model. Theanisotropic algebraic stress model is found to give better predictionthan the standard k-ε turbulence model. The predicted turbulent flowfield is in accordance to experimental data and the trend of theturbulence intensity can be effectively reflected in the simulation.
基金Supported by the Natural Science Foundation of Inner Mongolia (No.200408020715).
文摘The spatial structure of the velocity field in a stirred vessel with water has been measured and analyzed using the laser Doppler velocimeter technique, with the immersing depth and agitation speed of the impeller re-maining approximately constant. The experimental results were provided such as the mean velocity field, fluctuat-ing velocities, turbulent kinetic energy, Reynolds shear stress and time series of the velocity in the stirred tank. These results probably provided the valuable basis to further optimize and enlarge the stirred tank in the industrial process.
文摘AIM To evaluate the safety and efficacy of agitation thrombolysis(AT) combined with catheter-directed thrombolysis(CDT) for the treatment of non-cirrhotic acute portal vein thrombosis(PVT). METHODS Nine patients with non-cirrhotic acute PVT who underwent AT combined with CDT were analyzed retrospectively. Portography was carried out via the transjugular intrahepatic portosystemic(commonly known as TIP) or percutaneous transhepatic(commonly known as PT) route, followed by AT combined with CDT. Complications of the procedure, and the changes in clinical symptoms, hemodynamics of the portal vein and liver function were recorded. Follow-up was scheduled at1, 3 and 6 mo after treatment, and every 6 mo thereafter, or when the patients developed clinical symptoms related to PVT. Color Doppler ultrasound and contrast-enhanced computed tomography/magnetic resonance imaging were performed during the follow-up period to determine the condition of the portal vein.RESULTS AT combined with CDT was successfully performed. The portal vein was reached via the TIP route in 6 patients, and via the PT route in 3 patients. All clinical symptoms were relieved or disappeared, with the exception of 1 patient who died of intestinal necrosis 9 d after treatment. Significant differences in the changes in portal vein hemodynamics were observed, including the maximum lumen occupancy of PVT, portal vein pressure and flow velocity between pre-and posttreatment(P < 0.05). During the follow-up period, recurrence was observed in 1 patient at 19 mo after the procedure, and the portal vein was patent in the remaining patients.CONCLUSION AT combined with CDT is a safe and effective method for the treatment of non-cirrhotic acute PVT.
基金supported by the National Key Research and Development Program of China(2016YFB0301701)the National Natural Science Foundation of China(21808234,21878318,and 21938009)+3 种基金the DNL Cooperation Fund,Chinese Academy of Sciences(CAS)(DNL201902)the Strategic Priority Research Program of the CAS(XDA21060400)the QIBEBT and Dalian National Laboratory for Clean Energy of the CAS(QIBEBT ZZBS201803 and QIBEBT I201907)the CAS Key Technology Talent Program.
文摘Pneumatically agitated slurry reactors,including bubble column reactors and airlift loop reactors(ALRs),are important gas-liquid-solid multiphase reactors.These reactors have been widely applied in many processes,especially in the biological fermentation and energy chemical industry,due to their low shear stress,good mixing,perfect mass-/heat-transfer properties,and relatively low costs.To further improve the performance of slurry reactors(i.e.,mixing and mass/heat transfer)and to satisfy industrial require-ments(e.g.,temperature control,reduction of back-mixing,and product separation),the process intensi-fication of slurry reactors is essential.This article starts by reviewing the latest advancements in the intensification of mixing and mass/heat transfer in these two types of reactors.It then summarizes process-intensification methods for mixing and separation that allow continuous production in these slurry reactors.Process-intensification technology that integrates directional flow in an ALR with simple solid-liquid separation in a hydrocyclone is recommended for its high efficiency and low costs.This arti-cle also systematically addresses vital considerations and challenges,including flow regime discrimina-tion,gas spargers,solid particle effects,and other concerns in slurry reactors.It introduces the progress of numerical simulation using computational fluid dynamics(CFD)for the rational design of slurry reactors and discusses difficulties in modeling.Finally,it presents conclusions and perspectives on the design of industrial slurry reactors.
