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.

Effects of Acute Normovolemic Hemodilution on Perioperative Coagulation and Fibrinolysis in Elderly Patients Undergoing Hepatic Carcinectomy

Objective To observe the effects of acute normovolemic hemodilution （ANH） on coagulation function and fibrinolysis in elderly patients undergoing hepatic carcinectomy. Methods Thirty elderly patients （aged 60-70 years） with liver cancer （American Society of Anesthesiologists physical status I-II） scheduled for hepatic carcinectomy from February 2007 to February 2008 were randomly divided into ANH group （n= 15） and control group （n= 15）. After tracheal intubation, patients in ANH group and control group were infused with 6% hydroxyethyl starch （HES） （130/0.4）, and basic liquid containing 6% HES and routine Ringer＇s solution, respectively. In all the studied patients, blood samples were drawn at five different time points： before anesthesia induction （T1）, 30 minutes after ANH （T2）, 1 hour after start of operation （T3）, immediately after operation （T4）, and 24 hours after operation （Ts）. Then co- agulation function, soluble fibrin monomer complex （SFMC）, prothrombin fragment （F1＋2）, and platelet membrane glycoprotein （activated GPIIb/GPIIIa and P-selectin） were measured. Results The perioperative blood loss was not significantly different between the two groups （P〉 0.05）. The volume of allogeneic blood transfusion in ANH group was significantly smaller than that in control group （350.5±70.7 mL vs. 457.8±181.3 mL, P〈0.01）. Compared with the data ofT1, prothrombin time （PT） and activated partial thromboplastin time in both groups prolonged significantly after T3 （P〈0.05）, but still within normal range. There were no significant changes in thrombin time and D-dimer between the two groups and between different time points in each group （all P〉0.05）. SFMC and F1 ＋2 increased in both groups, but without statistical significance. P-selectin expression on the platelet surface of ANH group was significantly lowered atT2 andT3 compared with the level atT1 （P〈 0.05）. Compared with control group, P-selectin was sig-nificantly lower in ANH group atT2-T3 （all P〈0.05）. Conclusions In elderly patients undergoing resection of liver cancer, ANH may not hamper fibri- nolvsis and coagulation function. It coukt therefore be safe to largely reduce allogeneic blood transfusion.

Study on Localization Factors of Coagulation and Fibrinolysis in Glomerulonephritis

The intraglomerular distribution of alpha 2-plasmin inhi-bitor (α2-PI), plasminogen (PLG), fibronectin (FN) andfibrinogen related antigen (FRA), were examined in 118 ca-ses of primary or secondary glomerular disease by immuno-fluorescence method. The plasma concentrations of α2-PI,PLGand FRA were also measured simultaneously. The results ofthis study indicated that there was significant correlationbetween the deposition of α2-PI, PLG, FN, FRA and thedegree of histopathological changes in patients with severeglomerulonephritis. There was no significant correlation be-tween the intensity of α2-PI, PLG, FN and FRA depositionin glomeruli and the serum levels of α2-PI, PLG and FRA.

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.

Effects of Xuezhikang Capsule(血脂康胶囊) on Blood Lipids,Platelet Activation and Coagulation-Fibrinolysis Activity in Patients with Hyperlipidemia

Objective: To investigate the effects of Xuezhikang capsule (XZK,血脂康胶囊) on blood lipids level, platelet activation and coagulation-fibrinolysis activity in patients with hyerlipidemia. Methods: Seventy-six patients of hyperlipidemia were randomly divided into two groups, the XZK group (n=38) treated with XZK 600mg, taken two times per day and the Simvastatin (SIM) group (n = 38) treated with SIM 20mg per day, with the treatment lasting 8 weeks for both groups. Levels of fasting serum lipids, including total cholesterol (TC), triglyceride (TG), high and low density lipoprotein cholesterol (HDL-C and LDL-C), plasma GMP-140, fibrinogen (FIB), tissue plasminogen activator (t-PA), plasminogen activator inhibitor type-1 (PAI-) and prothrombin time (PT) were all measured before and 8 weeks after treatment. Data were compared before and after treatment and also compared with those measured in 20 healthy subjects of control. Results: Before treantment the levels of TC, TG and LDL-C were obviously higher and HDL-C level was significantly lower in hyperlipidemia patients than those in healthy subjects (P<0.05 or P<0.01). After 4-8 weeks of XZK treatment, the levels of TC, TG, LDL-C and FIB and activities of GMP-140 and PAI-1 were obviously lowered (P<0. 05 or P<0. 01). But in the SIM group there was no obvious change in FIB (P>0.05), instead it showed obvious increase of HDL-C and decrease of TC and LDL-C after treatment (P<0.05 or P<0.01). Conclusion: XZK could inhibit platelet activity and improve coagulation-fibrinolysis function, besides its lipids lowering effect.

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.

A Comparison Study of the Effects Injectable Contraceptive Cyclofem on Blood Coagulation and Fibrinolysis

Forty-six healthy women received Cyclofem (25mg medroxyprogesterone acetate with sing estradiol cypionate) and other /orly--five women, as control,received oral contraceptive pill (Ortho--Novum 1/35, containing norethisterone enantate ling and estradiol valerate 35fig) for nine months. Blood samples were taken during the follicular and luteal phases o/preu treatment, and for Cyclofem group, immediately prior to the 3rd and gth injections and 1 and 3 weeks a/ter the 3rd and gth injections, for Ortho Novum group, blood samples were taken on the irst day o[.the 3rd and gth pill cycles and 1 and 3 weeks later in both cycles. For both groups after at least 3 months nonhormonal method of contraception, blood sampling was repeated at follicular and luteal phases of a normal mentrual cycle.Coagulation and librinolysis parameter were detected including hemoglobin,platelet count, prothrombin time, APTT, fibrinogen, factor Vll, [actor X,plasminogen, in PAl, AT Ill (functional and immunological assays) and protein C.In the Cyclolem group, hemoglobin, platelet count, fibrinogen and /Octor X were not changed. Factor Vll significantly reduced. Prothrombin time and APTT showed minor changes. Plasminogen and protein C decreased while t-- PAl and AT 11.1 increased. These changes showed a dynamic balance between coagulatioll and fibrinolysis. In Ortho---Novum 1/35 group, platelet count, jactor X and [ibrinogen increased and prothrombin time and APTT accelerated. In fibrinolysis and anticoagulation system, plasminogen increased as well as protein C, but AT Ill declined. Those changes showed a tendency o[ hyper-coagulabllity state, fibrinolysis and anticoagulation were enhanced to a certain extent.The result of our study is that there are slight 'changes on coagulation and [ibrinolyls is in Cyclofem injectable contraceptive users.

Comparative Study on the Effects of Two Contraceptive Injections (Mesigyna, Cyclofem) on Blood Coagulation and Fibrinolysis

The effects of consecutively using the contraceptive injections (Mesigyna or Cyclofem) on both blood coagulation and fibrinolysis were evaluated on 94 Chinese women who had been injected with one of these two injections once a month for 9 months. To provide the evidences on the safety of long term use, relevant parameters were observed before the treatment, after the injection 3 and 9, as well as 3 months after drug withdrawing. The results were as follows: Among those who had been injected with Mesigyna, the levels of factor VII and factor X declined significantly during treatment. The activity of AT Ⅲ, plasminogen and the concentration of protein C also decreased. Moreover, the corresponding parameters did not recovered to the normal level after stopping treatment. Prothrombin time (PT) and activated partial thromboplastin time (APTT) were prolonged in the early period of treatment, but recovered to the normal at week 47 (injection withdrawn). No or slight change was observed in other parameters. Among the woman injected with Cyclofem, the concentrations of factor VII and plasminogen decreased over time, while the tissue plasminogen activator inhibitor (t PAI) levels increased after the 9 th injection and recovered to normal at week 47 after discontinuation of treatment. The results suggested that some significant parameter changes of coagulation and of fibrinolysis could be detected among long term users, but their impact on the fibrinolysis system was not obvious. The observed phenomenon did not show a tendency to facilitate thromboembolism and possibility of being harmful to the users. Thus, the observed changes should be regarded as the reactions to keep the equilibrium between coagulation and fibrinolysis and had no marked clinical pathological significance on the users.

Correction of Disorders in Tissue Perfusion, Blood Coagulation and Fibrinolysis with Orbita Apparatus on Terahertz Waves of Cell Metabolites

This article contains information on principle of operation, technical parameters and possible application of Orbita apparatus for hemodynamic, fibrinolytic and peripheral perfusion disorders treatment. A single exposure to terahertz waves emitted by Orbita apparatus, corresponding to frequencies of molecular absorption and emission spectra of atmospheric oxygen (129.0 GHz), completely cures coagulant and fibrinolytic disorders of animals with acute immobilization stress. A course of treatment with electromagnetic waves corresponding to frequencies of molecular absorption and emission spectra of nitrogen oxide (150.176 - 150.664) leads to normalization of disrupted peripheral tissue perfusion parameters of animal undergoing treatment and stimulates basal and induced output of nitrogen oxide. This leads to decrease in peripheral vascular resistance to microcirculation and increase in blood flow to microvasculature. Experimental data provided in this article serves as a proof of viability of Orbita apparatus for treatment of coagulant, fibrinolytic and tissue perfusion disorders.

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.

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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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.

Thrombin Activatable Fibrinolysis Inhibitor in Preeclmapsia and Gestational Hypertension throughout the Gestation

To clarify the role of TAFI in hypertensive disorders in pregnancy, 22 subjects, including 10 with pre-eclampsia （PE） and 12 with gestational hypertension were examined for the levels of TAFI and thrombin-antithrombin （TAT） complex. Thirty normal pregnant women served as controls. ELISA was employed for the detection. The results showed that the TAFI antigen levels in normal pregnancy group, gestational hypertension group and PE group were （85.35±24.69）%, （99.65±18.27）%, （110.12±23.36）%; （97.06±21.40）%, （114.08±27.76）%, （125.49±24.70）%; （106.6±19.21）%, （129.2±25.07）%, （139.1±30.12）%, in the 1st, 2nd and 3rd trimester respectively. No significant differences were found between the normal pregnancy group and gestational hypertension group but significant difference existed between normal pregnancy group and PE group in each trimester （P〈0.05）. TAT complexes were significantly higher in patients with PE than that in controls （P〈0.05）, but no correlation was found between TAT and TAFI. It is concluded that TAFI may contributed to the impairment of fibrinolysis in the patients with PE and may serves as a sensitive indicator for PE, but it may not help in the diagnosis of the gestational hypertension.

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.

Research on mine dustfall agents based on the mechanism of wetting and coagulation

Mine dust is classified as one of five natural coal mining disasters because it can harm the health of miners and poses a serious threat to the safety of the coal mine. Therefore, preparation of an effective dust suppression agent is highly desired. To improve the capture efficiency of fine dust, this study examines the dust suppression effects of various combinations of wetting agents, additives, and coagulation agents by using the optimum seeking method to reduce mine dust, particularly respirable particles. The optimal formula is shown to contain 10wt% fatty alcohol polyoxyethylene ether（JFC）, 4.96wt% cationic polyacrylamide, and 4wt% calcium chloride. The dust suppression effect can be achieved at 96.1% in 5 min by using the optimal formula.

Coagulation enhanced electrokinetic settling of mature fine oil sands tailings

The mature fine oil sand tailings(MFT) remain as slurry in the tailings pond for long time. The dewatering and consolidation of MFT for sustainable management is an important task for the mining industry. The objective of this study is to accelerate electrokinetic settling of MFT solids in suspensions in presence of optimal coagulant. In the first phase, optimal coagulant and coagulant dosage for settling of suspension are identified, i.e., ferric chloride at 350 mg/L. It is found that the chemical treatment is not much effective; the final solid content of the sediment is only 6.48% from an initial of 5%. In the second phase,combined coagulation and electrokinetic treatment is carried out to enhance the settling effect. The direct electric current is applied in continuous and intermittent modes on MFT suspensions placed in electrokinetic cell. The results show the final solid content reaches 23.74% under the combined application of350 mg/L ferric chloride and 218.75 V/m applied voltage gradient in the continuous mode. The intermittent current mode with 40% save in power consumption produces a settled sediment having 20.84% final solid content.

Properties and coagulation mechanisms of polyferric silicate sulfate with high concentration

Polyferric silicate sulfate （PFSS） with high concentration was prepared using the composite-poly method. The coagulation properties and mechanisms of this new complex were probed using TEM, Fe-Ferron timed complex-colorimetric method, and infrared spectrum method. The results showed that the flocculating effect of polyferric silicate sulfate had an advantage over polyferric sulfate （PFS）, as the optimum coagulation effect could be obtained when the Si/Fe mole ratio was 0.75 in accordance with its macrostructure of PFSS. According to the Fe-Ferron timed complex-colorimetric method, the Si species was mainly Sic, whereas, the Fe species were Fea and Fec in the copolymerization system. The infrared spectra indicated that the structure of these new flocculants was formed by polymers, mainly by olation, which was different from polyferric sulfate, and the vibration of M-OH-M of around 1100 cm^-1, also proved that there existed Fe-OH-Fe and its polymers in some forms.