Ultrafiltration with in-line coagulation for the removal of natural humic acid and membrane fouling mechanism

Experimental and theoretical analysis were made on the natural humic acid removal and the membrane fouling of ultrafiltration （UF） with in-line coagulation. The results showed dissolved organic carbon （DOC） and UV254 removals by the UF with in-line coagulation at pH 7 were increased from 28% to 53% and 40% to 78% in comparison with direct UF treatment respectively. At the same time, the analysis of high performance liquid chromatography showed that UF with coagulation had significant improvement of removal of humic acid with molecular weights less than 6000 Da in particular. Compared to direct UF, the in-line coagulation UF also kept more constant permeate flux and very slight increase oftransmembrane pressure during a filtration circle. Two typical membrane fouling models were used by inducing two coefficients Kc and Kp corresponding to cake filtration model and pore narrowing model respectively. It was found that membrane fouling by pore-narrowing effect was effectively alleviated and that by cake-filtration was much decreased by in-line coagulation. Under the condition of coagulation prior to ultrafiltration at pH 7, the cake layer formed on the membrane surface became thicker, but the membrane filtration resistance was lower than that at pH 5 with the extension of operation time.

Reduction of DOM fractions and their trihalomethane formation potential in surface river water by in-line coagulation with ceramic membrane filtration

This research was aimed at investigating the reduction of DOM fractions and their trihalomethane formation potential （THMFP） by in-line coagulation with 0.1 μm ceramic membrane filtration. The combination of ceramic membrane filtration with a coagulation process is an alternative technology which can be applied to enhance conventional coagulation processes in the field of water treatment and drinking water production. The Ping River water （high turbidity water） was selected as the raw surface water because it is currently the main raw water source for water supply production in the urban and rural areas of Chiang Mai Province. From the investigation, the results showed that the highest percent reductions of DOC, UV-254, and THMFP （47.6%, 71.0%, and 67.4%, respectively） were achieved from in-line coagulation with ceramic membrane filtration at polyaluminum chloride dosage 40 mg/L. Resin adsorption techniques were employed to characterize the DOM in raw surface water and filtered water. The results showed that the use of a ceramic membrane with in-line coagulation was able to most efficiently reduce the hydrophobic fraction （HPOA） （68.5%）, which was then followed by the hydrophilic fraction （HPIA） （49.3%）. The greater mass DOC reduction of these two fractions provided the highest THMFP reductions （55.1% and 37.2%, respectively）. Furthermore, the in-line coagulation with ceramic membrane filtration was able to reduce the hydrophobic （HPOB） fraction which is characterized by high reactivity toward THM formation. The percent reduction of mass DOC and THMFP of HPOB by in-line coagulation with ceramic membrane filtration was 45.9% and 48.0%, respectively.

Coagulation indices and fibrinogen degradation products as predictive biomarkers for tumor-node-metastasis staging and metastasis in gastric cancer

BACKGROUND Gastric cancer(GC)is a prevalent malignancy with a substantial health burden and high mortality rate,despite advances in prevention,early detection,and treatment.Compared with the global average,Asia,notably China,reports disproportionately high GC incidences.The disease often progresses asymptoma-tically in the early stages,leading to delayed diagnosis and compromised out-comes.Thus,it is crucial to identify early diagnostic biomarkers and enhance treatment strategies to improve patient outcomes and reduce mortality.METHODS Retrospectively analyzed the clinical data of 148 patients with GC treated at the Civil Aviation Shanghai Hospital between December 2022 and December 2023.The associations of coagulation indices-partial thromboplastin time(APTT),prothrombin time(PT),thrombin time(TT),fibrinogen,fibrinogen degradation products(FDP),fasting blood glucose,and D-dimer(D-D)with TNM stage and distant metastasis were examined.RESULTS Prolongation of APTT,PT,and TT was significantly correlated with the GC TNM stage.Hence,abnormal coagulation system activation was closely related to disease progression.Elevated FDP and D-D were significantly associated with distant metastasis in GC(P<0.05),suggesting that increased fibrinolytic activity contributes to increased metastatic risk.CONCLUSION Our Results reveal coagulation indices,FDPs as GC biomarkers,reflecting abnormal coagulation/fibrinolysis,aiding disease progression,metastasis prediction,and helping clinicians assess thrombotic risk for early intervention and personalized treatment plans.

Assessing mixing uniformity in microreactors via in-line spectroscopy

Mixing behavior is critical for enhancing the selectivity of fast chemical reactions in microreactors.A high Reynolds number(Re)improves the mixing rate and selectivity of the reactions,but some exceptions of increasing side product yield with the higher Re have been reported.This study investigated the mixing uniformity in microreactors with in-line UV-vis spectroscopy to clarify the relationship between reaction selectivity and chaotic mixing with the higher Re.A colorization experiment of thymolphthalein in an acidic solution was conducted with an excess acid amount to the base to indicate a non-uniformly mixed region.Non-uniformity significantly increased with Re.At the same time,the degree of mixing,which was measured by a usual decolorization experiment,showed that the mixing rate increased with Re.The in-line analysis of the Villermaux-Dushman reaction during the mixing clarified that side product yield significantly increased with Re at around 300 and then decreased at around 1100.These results suggest the compensation effect between the mixing uniformity and mixing rate on the selectivity of the mixing-sensitive reactions.Faster mixing,characterized by a larger Re,can disturb mixing uniformity and,in some cases,decrease reaction selectivity.

Risk Factors for Mortality in Critically Ill Patients with Coagulation Abnormalities:A Retrospective Cohort Study

Objective Coagulation abnormalities are common and prognostically significant in intensive care units(ICUs)and are associated with increased mortality.This study aimed to explore the association between the levels of coagulation markers and the risk of mortality among ICU patients with coagulation abnormalities.Methods This retrospective study investigated patients with coagulation abnormalities in the ICU between January 2021 and December 2022.The initial point for detecting hemostatic biomarkers due to clinical assessment of coagulation abnormalities was designated day 0.Patients were followed up for 28 days,and multivariate logistic regression analysis was utilized to identify risk factors for mortality.Results Of the 451 patients analyzed,115 died,and 336 were alive at the end of the 28-day period.Multivariate analysis revealed that elevated thrombin-antithrombin complex(TAT),tissue plasminogen activator inhibitor complex(tPAIC),prolonged prothrombin time,and thrombocytopenia were independent risk factors for mortality.For nonovert disseminated intravascular coagulation(DIC)patients,older age and thrombocytopenia were associated with increased risks of mortality,whereas elevated levels of plasminα2-plasmin inhibitor complex(PIC)were found to be independent predictors of survival.In patients with overt DIC,elevated levels of tPAIC were independently associated with increased risks of mortality.Nevertheless,thrombocytopenia was independently associated with increased risks of mortality in patients with pre-DIC.Conclusion Coagulation markers such as the TAT,tPAIC,PIC,and platelet count were significantly associated with mortality,underscoring the importance of maintaining a balance between coagulation and fibrinolysis.These findings highlight the potential for targeted therapeutic interventions based on specific coagulation markers to improve patient outcomes.

Comparison between sepsis-induced coagulopathy and sepsis-associated coagulopathy criteria in identifying sepsis-associated disseminated intravascular coagulation

BACKGROUND:Disseminated intravascular coagulation(DIC)is associated with increased mortality in sepsis patients.In this study,we aimed to assess the clinical ability of sepsis-induced coagulopathy(SIC)and sepsis-associated coagulopathy(SAC)criteria in identifying overt-DIC and preDIC status in sepsis patients.METHODS:Data from 419 sepsis patients were retrospectively collected from July 2018 to December 2022.The performances of the SIC and SAC were assessed to identify overt-DIC on days 1,3,7,or 14.The SIC status or SIC score on day 1,the SAC status or SAC score on day 1,and the sum of the SIC or SAC scores on days 1 and 3 were compared in terms of their ability to identify pre-DIC.The SIC or SAC status on day 1 was evaluated as a pre-DIC indicator for anticoagulant initiation.RESULTS:On day 1,the incidences of coagulopathy according to overt-DIC,SIC and SAC criteria were 11.7%,22.0%and 31.5%,respectively.The specificity of SIC for identifying overt-DIC was significantly higher than that of the SAC criteria from day 1 to day 14(P<0.05).On day 1,the SIC score with a cut-off value>3 had a significantly higher sensitivity(72.00%)and area under the curve(AUC)(0.69)in identifying pre-DIC than did the SIC or SAC status(sensitivity:SIC status 44.00%,SAC status 52.00%;AUC:SIC status 0.62,SAC status 0.61).The sum of the SIC scores on days 1 and 3 had a higher AUC value for identifying the pre-DIC state than that of SAC(0.79 vs.0.69,P<0.001).Favorable effects of anticoagulant therapy were observed in SIC(adjusted hazard ratio[HR]=0.216,95%confidence interval[95%CI]:0.060–0.783,P=0.018)and SAC(adjusted HR=0.146,95%CI:0.041–0.513,P=0.003).CONCLUSION:The SIC and SAC seem to be valuable for predicting overt-DIC.The sum of SIC scores on days 1 and 3 has the potential to help identify pre-DIC.

Electrocoagulation efficiency probed using electrochemical impedance spectroscopy

In order to treat the polluted discharge from El-Jadida,Morocco,a method of electrocoagulation using aluminum electrodes was used.This approach was coupled for the first time with high-frequency electrochemical impedance spectroscopy(EIS).Significant pollutant abatementwas observed after 30 min,at a current density of 190.5 A·m^(-2),with a specific electrical energy consumption of 1.58 kW·h(per gram of eliminated carbon organic demand(COD))and specific aluminum consumption of 0.11 g·g^(-1):electrocoagulation proved to be particularly effective,achieving 85.7%elimination of COD and a decrease of total dissolved solid(TDS)and electrical conductivity(EC)levels from 2430 mg·L^(-1)to 1773 mg·L^(-1)and from 4230μS·cm^(-1)to 3210μS·cm^(-1),respectively.As for USP and ORP,they decreased from 2.5 to 1.87 and from 244.6 mV to 51 mV,respectively.The inductance of the electrocoagulation system measured by EIS was modeled through an electrical equivalent circuit.When the applied intensity increased,the coagulation resistance increased suddenly when the applied electrical current reached 0.2 A(current density:95.2 A·m^(-2)).At this point,the rate of COD abatement versus SEEC(specific electrical energy consumption decreases which shows that the EC process should be combined with another process to improve its efficiency,such as ultrasound.

Effects of Coagulation and Ozonation Pretreatments on Biochemical Treatment of Fluid Catalytic Cracking Wastewater

Fluid catalytic cracking (FCC) salty wastewaters, containing quaternary ammonium compounds (QACs), are very difficult to treat by biochemical process. Anoxic/oxic (A/O) biochemical system, based on nitrification and denitrification reactions, was used to assess their possible biodegradation. Because of the negative effects of high salt concentration (3%), heavy metals and toxic organic matter on microorganisms’ activities, some techniques consisting of dilution, coagulation and flocculation, and ozonation pretreatments, were gradually tested to evaluate chemical oxygen demand (COD), ammonia-nitrogen (ammonia-N) and total nitrogen (TN) removal rates. In this process of FCC wastewater, starting with university-domesticated sludge, the ammonia-N and TN removal rates were worst. However, when using domesticated SBR’s sludge and operating with five-fold daily diluted influent (thus reducing salt concentration), the ammonia-N removal reached about 57% while the TN removal rate was less than 37% meaning an amelioration of the nitrification process. However, by reducing the dilution factors, these results were inflected after some days of operation, with ammonia-N removal decreasing and TN barely removed meaning a poor nitrification. Even by reducing heavy metals concentration with coagulation/flocculation process, the results never changed. Thereafter, by using ozonation pre-treatment to degrade the detected organic matter of di-tert-butylphenol and certain isoparaffins, COD, ammonia-N and TN removal rates reached 92%, 62% and 61%, respectively. These results showed that the activities of the microorganisms were increased, thus indicating a net denitrification and nitrification reactions improvement.

Hybrid argon plasma coagulation for the treatment of Barrett’s esophagus:A prospective,multicenter study

BACKGROUND The incidence of Barrett’s esophagus(BE)in China is lower compared to the Western populations.Hence,studies conducted in the Chinese population has been limited.The current treatment options available for BE treatment includes argon plasma coagulation(APC),radiofrequency ablation and cryoablation,all with varying degrees of success.AIM To determine the efficacy and safety of HybridAPC in the treatment of BE.METHODS The study cohort consisted of patients with BE who underwent HybridAPC ablation treatment.These procedures were performed by seven endoscopists from different tertiary hospitals.The duration of the procedure,curative rate,complications and recurrent rate by 1-year follow-up were recorded.RESULTS Eighty individuals were enrolled for treatment from July 2017 to June 2020,comprising of 39 males and 41 females with a median age of 54 years(range,30 to 83 years).The technical success rate of HybridAPC was 100%and the overall curative rate was 98.15%.No severe complications occurred during the operation.BE cases were classified as short-segment BE and long-segment BE.Patients with short-segment BE were all considered cured without complications.Thirty-six patients completed the one-year follow-up without recurrence.Twenty-four percent had mild dysplasia which were all resolved with one post-procedural treatment.The mean duration of the procedure was 10.94±6.52 min.CONCLUSION Treatment of BE with HybridAPC was found to be a simple and quick procedure that is safe and effective during the short-term follow-up,especially in cases of short-segment BE.This technique could be considered as a feasible alternative ablation therapy for BE.

Research on Treating Thallium by Enhanced Coagulation Oxidation Process

[Objective] The aim was to treat acidic wastewater containing thallium by enhanced coagulation oxidation process. [Method] Enhanced coagulation oxidation process was made use of to remove thallium in the acidic wastewater in the experiment under the condition of 0.05 kg/L of potassium permanganate, 30% hydrogen peroxide and 0.05 kg/L calcium hypochlorite as oxidant, together with 0.092 kg/L CaO as coagulation. [Result] The results showed that thallium removal efficiencies achieved 99.98%, 99.1% and 99.95% when dosages of KMnO4, H2O2and Ca（ClO）2were added at 20, 2.2 and 37 ml, respectively, under the condition of 30 ml 0.092kg/L CaO being dosed and 99.93%, 99.69% and 99.98% were achieved when different dosages of CaO were added at 25, 35 and 25 ml, under the condition of 20ml KMnO4, 2.2 ml H2O2and 37 ml Ca（ClO）2respectively. [Conclusion] The experiment demonstrates that good removal effects of removal thallium from the acidic wastewater would be achieved by enhanced coagulation oxidation process.

STRUCTURE-FUNCTION FEATURES AND EFFECTS ON BLOOD COAGULATION OF SNAKE VENOM SERINE PROTEASES*

Snake venoms,especially those from the two subfamilies,Crotalinae and Viperinae,contained a lot of serine proteases. They were responsible for the hemorrhage,shock,or disorder of blood coagulation after envenomation. They acted,by activating,inactivating,or other converting effects,on almost all the components of hemostatic and fibrinolytic systems. Their sequences were homologous to trypsin-kallikrein serine proteases. Variation of primary sequences out of active center results in the difference of substrate specificities and the further difference of biological and pharmacological activities. Because of their common and unique properties compared to their physiological corresponding factors,snake venom proteases are proved to be an excellent model for the study of protease substrate discriminating mechanism. Furthermore,they have found an important position both in basic research and application of hemostasis and thrombosis in clinic.

Percutaneous Microwave Coagulation Therapy for Patients with Primary and Metastatic Hepatic Tumors

Objective: To evaluate the efficacy and safety of percutaneous microwave coagulation therapy (PMCT) for patients with primary and metastatic hepatic tumors.Methods: The enrolled 100 patients with 186 tumor nodules who underwent PMCT included 79 cases of primary or recurrent liver cancers and 21 cases of metastatic liver cancer. The tumors were divided into two groups according to the tumor size in diameter: group A, 0.5 cm?<3 cm; group B, ≥3 cm?<5 cm. Under local and/or epidural anesthesia, a single percutaneous microwave antenna (or two antennas array applicator) was inserted directly into the tumor in the liver for thermo-coagulation with the aid of ultrasound guidance.Results: Among the 186 lesions in 100 patients with primary and metastatic liver cancers, in group A, 123 (66%) were coagulated once. A Follow-up of 6–12 months demonstrated that 112 lesions (91%) showed no local recurrence by CT or MRI; In group B, of the 63 lesions (33.87%) coagulated twice, 31 (49%) showed no local recurrence by CT or MRI during a follow-up of 6 months. There were no serious clinical side effects or complications in all the PMCT patients.Conclusion: PMCT gives satisfactory curative effect on tumors with <3 cm in size. It is partly effective on lesions ≥3 cm?<5 cm in size. It is a minimally invasive and effective therapy, can be used safely in the field of percutaneous hepatis surgery, and carried out even in patients with poor liver function. Key words hepatocellular carcinoma - microwave - coagulation - therapy

Composite control for coagulation process with time delay and disturbances

A composite control scheme consisting of modepredictive control （MPC） and disturbance observer （DOB） iproposed to solve the control performance degradationproblem of the turbidity of the treated water in the presence osignificant changes in raw water quality, water flow rate andinternal model mismatch disturbances. The MPC is employedas a feedback controller for the coagulation process with alarge time delay. The DOB is adopted to estimate the severedisturbances in the turbidity control, such as large changes inraw water quality and water flow rate. The estimated valuesare applied for feed-forward compensation to rejecdisturbances. Finally, the disturbance rejection performancesfor step disturbances and time-varying disturbances in thenominal case and model mismatch case are tested. Thesimulation results illustrate that, compared with the MPCmethod, the proposed method can significantly improve thedisturbance rejection performance in the turbidity control othe treated water, no matter if in the presence of externadisturbances or internal model mismatch disturbances.

Effect of coagulation pretreatment on the fouling of ultrafiltration membrane

The purpose of this study is to understand the effect and mechanism of preventing membrane fouling, by coagulation pretreatment, in terms of fractional component and molecular weight of natural organic matter （NOM）. A relatively higher molecular weight （MW） of hydrophobic compounds was responsible for a rapid decline in the ultrafiltration flux. Coagulation could effectively remove the hydrophobic organics, resulting in the increase of flux. It was found that a lower MW of neutral hydrophilic compounds, which could remove inadequately by coagulation, was responsible for the slow declining flux. The fluxes in the filtration of coagulated water and supernatant water were compared and the results showed that a lower MW of neutral hydrophilic compounds remained in the supernatant water after coagulation could be rejected by a membrane, resulting in fouling. It was also found that the coagulated flocs could absorb neutral hydrophilic compounds effectively. Therefore, with the coagulated flocs formed on the membrane surface, the flux decline could be improved.

Transfusion and coagulation management in liver transplantation

There is wide variation in the management of coagulation and blood transfusion practice in liver transplantation. The use of blood products intraoperatively is declining and transfusion free transplantations take place ever more frequently. Allogenic blood products have been shown to increase morbidity and mortality. Primary haemostasis, coagulation and fibrinolysis are altered by liver disease. This, combined with intraoperative disturbances of coagulation, increases the risk of bleeding. Meanwhile, the rebalancing of coagulation homeostasis can put patients at risk of hypercoagulability and thrombosis. The application of the principles of patient blood management to transplantation can reduce the risk of transfusion. This includes: preoperative recognition and treatment of anaemia, reduction of perioperative blood loss and the use of restrictive haemoglobin based transfusion triggers. The use of point of care coagulation monitoring using whole blood viscoelastic testing provides a picture of the complete coagulation process by which to guide and direct coagulation management. Pharmacological methods to reduce blood loss include the use of anti-fibrinolytic drugs to reduce fibrinolysis, and rarely, the use of recombinant factor VIIa. Factor concentrates are increasingly used; fibrinogen concentrates to improve clot strength and stability, and prothrombin complex concentrates to improve thrombin generation. Non-pharmacological methods to reduce blood loss include surgical utilisation of the piggyback technique and maintenance of a low central venous pressure. The use of intraoperative cell salvage and normovolaemic haemodilution reduces allogenic blood transfusion. Further research into methods of decreasing blood loss and alternatives to blood transfusion remains necessary to continue to improve outcomes after transplantation.

Features and mechanism for coagulation－flocculation processes of polyaluminum chloride

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Large eddy simulation of a planar jet flow with nanoparticle coagulation

Coagulation and growth of nanoparticles subject to large coherent structures in a planar jet has been explored by using large eddy simulation. The particle field is obtained by employing a moment method to approximate the nanoparticle general dynamic equa- tion. An incompressible fluid containing particles of 1 nm in diameter is projected into a particle-free ambient. The results show that the coherent structures dominate the evolution of the nanoparticle number intensity, diameter and polydispersity distributions as the jet develops. In addition, the coherent structures act to increase the diffusion of particles, and the vortex rolling-up makes the particles distributing more irregularly while the vortex pairing causes particle distributions to become uniform. As the jet travels downstream, the time-averaged particle number concentration becomes lower in the jet core and higher in the outskirts, whereas the time- averaged particle mass over the entire flow field maintains unaltered, and the time-averaged particle diameter and geometric standard deviations grow and reach their maximum on the interface of the jet region and the ambient.

The effect of coupling coagulation and flocculation with membrane filtration in water treatment:A review

Water supply and sanitation demands are foreseen to face enormous challenges over the coming decades to meet the fast growing needs in a global perspective. Significant growth in the industry is predicted and membrane separation technologies have been identified as one of the possible solutions to meet future demands. Application and implementation of membrane technology is expected both in production of potable water as well as in treatment of wastewater. In potable water production membranes are substituting conventional separation technologies due to the superior performance, potential for less chemical use and sludge production, as well as the potential to fulfill hygienic barrier requirements. Membrane bio-reactor （MBR） technology is probably the membrane process which has had most success and has the best prospects for the future in wastewater treatment. Trends and developments indicate that this technology is becoming accepted and is rapidly becoming the best available technology for many wastewater treatment applications. A major drawback of MBR systems is membrane fouling. Studies have shown that fouling mitigation in MBR systems can potentially be done by coupling coagulation and flocculation to the process.

Efficacy and complications of argon plasma coagulation for hemorrhagic chronic radiation proctitis

BACKGROUND Chronic radiation proctitis(CRP) is a complication which occurs in 1%-5% of patients who undergo radiotherapy for pelvic malignancies. Although a wide range of therapeutic modalities are available, there is no literature to date showing any particularly appropriate therapeutic modality for each disease stage. Argon plasma coagulation(APC) is currently recommended as the firstchoice treatment for hemorrhagic CRP, however, its indication based on longterm follow-up is still unclear. On the hypothesis that the long-term efficacy and safety of APC are not fully understood, we reviewed APC treatment for patients with hemorrhagic CRP from a single center.AIM To assess the long-term efficacy and safety of APC for hemorrhagic CRP.METHODS This is a retrospective study of consecutive patients treated with APC for hemorrhagic CRP from January 2013 to October 2017. Demographics, clinical variables, and typical endoscopic features were recorded independently. Success was defined as either cessation of bleeding or only occasional traces of bloody stools with no further treatments for at least 12 mo after the last APC treatment.We performed univariate and multivariate analyses to identify factors associated with success and risk factors for fistulas.RESULTS Forty-five patients with a median follow-up period of 24 mo(range: 12-67 mo)were enrolled. Fifteen(33.3%) patients required blood transfusion before APC.Successful treatment with APC was achieved in 31(68.9%) patients. The mean number of APC sessions was 1.3(1-3). Multivariate analysis showed that APC failure was independently associated with telangiectasias present on more than50% of the surface area [odds ratio(OR) = 6.53, 95% confidence interval(CI): 1.09-39.19, P = 0.04] and ulcerated area greater than 1 cm^2(OR = 8.15, 95%CI: 1.63-40.88, P = 0.01). Six(13.3%) patients had severe complications involving rectal fistulation. The only factor significantly associated with severe complications was ulcerated area greater than 1 cm^2(P = 0.035).CONCLUSION The long-term efficacy of APC for hemorrhagic CRP is uncertain in patients with telangiectasias present on > 50% of the surface area and ulceration > 1 cm^2.

Coagulation of micro-polluted Pearl River water with IPF-PACls

Water samples collected from early March 2001 to the end of April 2002 at the branch of Pearl River around the Guangzhou City were analyzed for its micro-polluted characteristics. The coagulation behavior of polyaluminum chlorides(PACls) was then examined focusing on the effect of primary water quality and speciation distribution. The results showed that PACls exhibit better coagulation efficiency than alum in accordance with the different speciation. The turbidity removal property of PACls is evidently better than alum at low dosage. While in neutral zone(about 6.5—7.5), the turbidity removal of PACls decreases owing to the restabilization of particles at higher dosage. The organic matters in raw water exhibit marked influence on coagulation. In acidic zone, organic matters complex with polymer species and promote the formation of flocs. With an increase in pH, the complexation of organics with polymer species gradually decreases, and the removal of organics mainly depends on adsorption. The effect is evidently improved with the raise of B value.