[Clinical value of TDI combined with 2D-STI on evaluating the microcirculation dysfunction and left ventricular dysfunction in patients with non-obstructive coronary angina].

Objective: To explore the value of tissue Doppler imaging (TDI) combined with two-dimensional speckle tracking imaging (2D-STI) at rest on evaluating microcirculation dysfunction and left ventricular dysfunction in patients with angina and no obstructive coronary artery disease(ANOCA). Methods: This retrospective study recruited 78 ANOCA patients, who hospitalized in the People's Hospital of Liaoning Province from August 2019 to July 2021. These patients underwent conventional echocardiography examination, including TDI and 2D-STI, to evaluate the left ventricular dysfunction, and adenosine stress echocardiography (SE) to evaluate the coronary flow velocity reserve (CFVR). ANOCA patients were divided into coronary microcirculation dysfunction CMD group (CFVR<2) and control group (CFVR≥2) according to CFVR. Clinical data, routine echocardiographic parameters, TDI parameters including isovolumic contraction time (IVCT), isovolumic relaxation time (IVRT), ejection time (ET), and STI parameters including global longitudinal peak strain (GLS), time to peak (TTP); peak strain dispersion (PSD) were compared between the two groups. Binary logistic regression was used to analyze the risk factors of CMD and the predictive value of each parameter to construct a joint prediction model for the diagnosis of CMD in this patient cohort. Results: The mean age was (55.5±11.2) years, 43 (55%) patients were females in this patient cohort, 38 (49%) patienst were didvided into the CMD group and 40 (51%) into the control group. Age, prevalence of hypertension, diabetes, dyslipidemia, and smokers were significantly higher in the CMD group than in the control group (all P<0.05). Tei index was higher, IVCT and TTP were longer, PSD was higher, ET was shorter, and absolute GLS was lower in the CMD group than in the control group (all P<0.05). The results of logistic regression analysis showed that longer IVCT, higher Tei index, higher time to PSD and lower absolute GLS were the independent risk factors of CMD. The ROC curve revealed that the predicting efficacy on CMD was satisfactiory with the combined predictors: AUC=0.884, sensitivity of 82% and specificity of 80%. Conclusions: TDI combined with 2D-STI is associated with a good diagnostic value on the diagnosis of CMD and left ventricular dysfunction in patients with ANOCA, which provides a feasible non-invasive tool for the diagnosis of CMD and risk stratification of patients with ANOCA.

[Study and application of legislative changes on liability for medical damage in the Civil Code].

The Civil Code of the People's Republic of China (hereinafter referred to as the "Civil Code") has been implemented on January 1, 2021. The "Civil Code" involves clinical medical diagnosis and treatment work legal norms and legal liabilities. Except for the revisions of the key contents of the "Medical Damage Liability" part of the Tort Liability Law, most of them remains following the original regulations. In order to enable the managers and medical staff of medical institutions to fully understand the relevant provisions of the Civil Code and their clinical applications, this article is divided into ten parts for a comprehensive and systematic interpretation.

[The role of S100A8/RAGE and Caveolin-1 and the effect of roxithromycin on their expression in a rat model of neutrophilic asthma].

Objective: To explore the role of S100A8, the receptor for advanced glycation endproducts (RAGE) and Caveolin-1 in neutrophilic asthmatic rats, and to further study the intervention of roxithromycin and the possible mechanisms. Methods: Male Brown Norway rats were randomly assigned to a control group, an asthma group and a Roxithromycin group. The asthmatic rat model was established by intraperitoneal injection of ovalbumin (OVA) and Freund's complete adjuvant (FCA) mixture, and aerosol inhalation of OVA. Rats in the Roxithromycin group were given roxithromycin injection 30 mg/kg 30 minutes before each challenge. Rats in the control and the asthma groups were replaced with equal volumes of saline, respectively. Bronchoalveolar lavage fluid (BALF) neutrophil percentage (Neu%) and pathological changes of pulmonary tissue (hematoxylin-eosin, HE staining) were measured to confirm the establishment of asthmatic models. The concentration of inflammatory cytokines and S100A8 were quantified by enzyme-linked immunosorbent assay (ELISA), and the expression of Caveolin-1 and RAGE at protein levels were detected by immunohistochemistry and Western blot. Results: Neu% in BALF of the asthma group was significantly higher than those of the control group, and Neu% in the Roxithromycin group was lower than the asthma group (all P<0.01). Pulmonary histology revealed that there were a large number of inflammatory cells infiltrated in the bronchial and perivascular, pulmonary interstitial and alveolar spaces, and the bronchial wall and smooth muscles were thickened obviously in the asthma group. Rats in the Roxithromycin group showed milder inflammation and airway remodeling change than the asthma group. There was no obvious pathological damage in the control group. The concentration of IL-6 and IL-17 in BALF and serum of rats in the asthma group were significantly higher than those in the control group (P<0.01), and Roxithromycin inhibited the high expression of these cytokines (P<0.05). The expression of S100A8 and RAGE in the asthma group were significantly higher than those in the control group [(20.6±4.4) vs (7.1±2.0) ng/L; (885±118) vs (462±102) ng/L; (14.2±1.7) vs (7.6±1.8) ng/L; (774±166) vs (406±69) ng/L, all P<0.05], and Roxithromycin inhibited the high expression of these proteins [(14.3±3.7) vs (20.6±4.4) ng/L; (650±53) vs (885±118) ng/L; (10.4±1.2) vs (14.2±1.7) ng/L; (560±64) vs (728±72) ng/L] (all P<0.05). Meanwhile, the expression of Caveolin-1 in the asthma group was significantly lower than that in the control group (P<0.01), and Roxithromycin up-regulated its expression (P<0.01). Correlation analysis showed that there was a significantly positive correlation between the expression of S100A8 and RAGE (r=0.706, P<0.01), while there was a significantly negative correlation between the expression of S100A8 and Caveolin-1 (r=-0.775, P<0.01), and between the expression of Caveolin-1 and RAGE (r=-0.919, P<0.01). Conclusion: S100A8 and Caveolin-1 may play an important role in neutrophilic asthma via RAGE, and Roxithromycin may exerts anti-inflammatory effects and inhibition of airway remodeling partly through this signaling pathway.

[Role of roxithromycin on glucocorticoid resistance of human bronchial epithelial cells and its mechanism].

Objective: To explore the effects of roxithromycin (RXM) on glucocorticoid resistance of human bronchial epithelial cells exposed to smoke and its mechanism. Methods: Beas-2B cells as the research object were grouped into: control group, 10%cigarette smoke extract (CSE) group, roxithromycin (RXM)+ 10%CSE group. With 10%CSE intervention in the 10%CSE group, 10%CSE and RXM intervention in the RXM+ 10%CSE group, complete culture solution intervention in the control group. Interleukin-8 (IL-8) levels were measured by enzyme linked immunosorbent assay (ELISA) and IL-8 inhibition rate and dexamethasone half inhibitory concentration (IC50-Dex) were calculated; the expression of histone deacetylase 2 (HDAC2) protein was detected by immunofluorescence (IF) and Western blotting (WB). Results: In response to dexamethasone at the concentration of 10(-9,) 10(-8,) 10(-7) and 10(-6) mol/L successively, the IL-8 inhibition rates of RXM+ 10%CSE group [(27.55±3.81)%, (49.60±1.45)%, (55.36±3.36)%, (60.32±3.13)%, respectively] were lower than those of control group [(32.85±2.56)%, (57.12±2.81)%, (60.81±2.08)%, (67.24±3.50)%, respectively], but higher than those of 10%CSE group [(19.15±1.69)%, (37.02±2.30)%, (47.15±2.01)%, (52.09±1.57)%, respectively] (all P<0.05). In contrast, the IC50-Dex of RXM+ 10%CSE group [(4.94±1.62)×10(-8)] was significantly higher than that of control group [(1.75±0.77)×10(-8)], but lower than that of 10%CSE group [(2.92±0.78)×10(-7)] (both P<0.01). The expression of HDAC2 protein of 10%CSE group (0.011±0.004 from IF and 0.46±0.10 from WB) was lower than that of control group (0.037±0.005 and 0.91±0.06, correspondingly), while RXM+ 10%CSE group (0.025±0.005 and 0.77±0.09, correspondingly) was lower than that of control group but higher than that of 10%CSE group (all P<0.05). Conclusion: Roxithromycin may restrain tobacco smoke exposure-induced glucocorticoid resistance in human bronchial epithelial cells through upregulating HDAC2 expression.

[Clinical application of adult comorbidity evaluation-27 in endometrial cancer].

Objective: To investigate the significant role of the clinical application of adult comorbidity evaluation-27 (ACE-27) in endometrial cancer (EC). Methods: A total of 847 EC patients were included during Jan. 1985 to Dec. 2015 from Tianjin Medical University General Hospital. The clinical data of the patients were collected and analyzed retrospectively. All of the patients were received operation with no chemotherapy and radiotherapy before operation. The average age was 57.6 years old (range from 25 to 85 years old). The average follow-up period was 59.0 months (range from 2 to 312 months). The comorbidity of the patients was evaluated by ACE-27. EC patients survival was analyzed by Kaplan-Meier survival curve. The relationship between the prognosis of EC and ACE-27, age, body mass index (BMI) , pathological characteristic were showed by Cox modeling. Results: (1) The patient number of score 0, 1, 2 and 3 of ACE-27 in EC patients were respectively 311 (36.7%), 263 (31.1%), 132 (15.6%) and 141 (16.6%) cases. (2) Kaplan-Meier survival curve analysis showed that overall survival time of EC patients was gradually decreased as increased score of ACE-27 (χ2=19.003, P=0.000) . In the patients of BMI<25 kg/m2 and BMI 25-<30 kg/m2, International Federation of Gynecology and Obstetrics (FIGO) stage Ⅰ, endometrial adenocarcinoma type and the overall survival time of those EC patients were gradually decreased as increased score of ACE-27 (P<0.05) . However, there was no statistically significant difference in overall survival time for patients with BMI ≥30 kg/m2, FIGO stage with Ⅱ-Ⅳand non-endometrial adenocarcinoma type (P>0.05). Per unvariate logistic modeling showed that the risk of death in score 3 of ACE-27 was increased compared with score 0 of ACE-27 (OR=2.53, P=0.000) . The overall survival time in EC patients with aged 50-59, 60-69 and ≥70 years old, BMI 25-<30 kg/m2 and ≥ 30 kg/m2, G3, FIGO stage Ⅱ-Ⅳ and non-endometrial adenocarcinoma type were significantly decreased compared with those aged <50 years old, BMI < 25 kg/m2, G1, FIGO stage Ⅰ and endometrial adenocarcinoma type (all P<0.05) . Further we found that postoperative chemotherapy or radiotherapy rate were decreased for EC patients with FIGO staging Ⅲ or Ⅳ as the increase of ACE-27 score, but there was no statistically significant difference (P>0.05). (3) Per multivariate logistic modeling showed that the risks of death in score 3 of ACE-27 was increased compared with score 0 of ACE-27 among age-adjusted, BMI, histological grade, FIGO stage and pathologic type (OR=2.40, P=0.000) . Per multivariate logistic modeling showed that, the overall survival time in EC patients with aged 60-69 and ≥70 years old, BMI 25-<30 kg/m2 and ≥30 kg/m2, FIGO stage Ⅲ-Ⅳ and non- endometrial adenocarcinoma type remain significantly decreased compared with those aged <50 years old, BMI<25 kg/m2, FIGO stage Ⅰ and endometrial adenocarcinoma type (P<0.05) , but there was no statistically significant difference in histological grade (P>0.05). Conclusions: ACE-27 may become one of the factors of predictive therapy and the prognosis for EC patients. The detailed clinical data of comorbidity should be collected to evaluate prognosis and therapy plan.

Molecular characterization of classical and nonclassical MHC class I genes from the golden pheasant (Chrysolophus pictus).

Classical major histocompatibility complex (MHC) class I allelic polymorphism is essential for competent antigen presentation. To improve the genotyping efforts in the golden pheasant, it is necessary to differentiate more accurately between classical and nonclassical class I molecules. In our study, all MHC class I genes were isolated from one golden pheasant based on two overlapping PCR amplifications. In total, six full-length class I nucleotide sequences (A-F) were identified, and four were novel. Two (A and C) belonged to the IA1 gene, two (B and D) were alleles derived from the IA2 gene through transgene amplification, and two (E and F) comprised a third novel locus, IA3 that was excluded from the core region of the golden pheasant MHC-B. IA1 and IA2 exhibited the broad expression profiles characteristic of classical loci, while IA3 showed no expression in multiple tissues and was therefore defined as a nonclassical gene. Phylogenetic analysis indicated that the three IA genes in the golden pheasant share a much closer evolutionary relationship than the corresponding sequences in other galliform species. This observation was consistent with high sequence similarity among them, which likely arises from the homogenizing effect of recombination. Our careful distinction between the classical and nonclassical MHC class I genes in the golden pheasant lays the foundation for developing locus-specific genotyping and establishing a good molecular marker system of classical MHC I loci.

Simultaneous copper ion removal and hydrogen production from water over a TiO2 nanotube photocatalyst.

A one-dimensional (1-D) mesoporous TiO2 nanotube (TiNT) was successfully synthesized via a hydrothermal-calcination process, and employed in simultaneous photocatalytic Cu(2+) removal and H2 production. Under irradiation, Cu(2+) in the wide concentration range of 8-800 ppm, could be reduced rapidly, and the reduction was not severely impacted by co-existing inorganic ions in solution. Simultaneous with Cu(2+) reduction, noticeable H2 was produced over the in-situ fabricated Cu incorporated TiNT (Cu-TiNT) photocatalyst, while H2 evolution rate was controlled by the Cu(2+) reduction process, due to competition of electron capture between protons and Cu(2+). In addition, H2 generation activity of Cu-TiNT depended on the initial Cu(2+)/Ti ratio, and could be depressed by co-existing ions in solution. Fast Cu(2+) reduction and remarkable H2 evolution confirmed the feasibility of simultaneous Cu(2+) removal and H2 production over a TiNT photocatalyst.

Effect of 200 days' sludge retention time on performance of a pilot scale submerged membrane bioreactor for high strength industrial wastewater treatment.

A high strength industrial wastewater was treated using a pilot scale submerged membrane bioreactor (MBR) at a sludge retention time (SRT) of 200 d. The MBR was operated at a high sludge concentration of 20 g/L and a low F/M ratio of 0.11 during 300 d of operation. It was found that the MBR could achieve COD and TOC overall removal efficiencies at more than 99 and 98% TN removal. The turbidity of the permeate was consistently in the range of 0.123 to 0.136 NTU and colour254 absorbance readings varied from 0.0912 to 0.0962 a.u. cm(-1). The sludge concentration was inversely proportional to the hydraulic retention time (HRT), yielded excellent organic removal and extremely low sludge production (0.0016 kgVSS/day).

Removal of humic acid foulant from ultrafiltration membrane surface using photocatalytic oxidation process.

The experimental results indicated that without the TiO2 particles and PCO treatment, the permeate flux of ultrafiltration (UF) membrane declined to 40% of the initial permeate flux after 8 hours filtration. Feeding the humic acid solution with TiO2 particles dosage of 1 g/L with calcium ions into UF membrane, after the same filtration time and PCO reaction at 120 minutes, the permeate flux was increased to about 90% of the initial permeate flux. At longer PCO reaction times, a better water quality of UF permeate was observed. It has been found that with the coexistence of calcium ions in humic acid solution, the smaller molecular fragments of humic acid (HA) generated by PCO reaction may be transferred to the surface of TiO2 by means of adsorption. The humic acid adsorption by TiO2 in the presence of Ca2+ is also pH dependent. The adsorption rates were 21.0, 14.9 and 10.8 ppmTOC/gTiO2 for pH value of 4, 7 and 10 respectively. The combination of effects of PCO mineralization of humic acid into CO2 and adsorption of humic acid by TiO2 through the forming of HA-Ca(2+)-TiO2 aggregate particles were responsible for the removal of humic acid foulant from UF membrane surface.

Characterization and ultrafiltration of semiconductor indium phosphide (InP) wastewater for recycling.

This research work investigated the physical and chemical properties of a new type of wastewater produced from the semiconductor industry. The wastewater generated from indium phosphide (InP) wafer backgrinding and sawing processes was characterized in term of its particle size distribution (PSD), zeta potential, suspended and dissolved solids, total organic carbon, and turbidity. The wastewater contained high concentration of fine InP dusts with a size ranging from 0.07 - 1.44 mm. In spite of its high concentration of suspended solids resulting in high turbidity up to 371 NTU, the wastewater contained very low organic matters (TOC < 2.2 mg l(-1)) and other inorganic impurities (SO4(2-) < 0.21 mg l(-1) and Na+ < 0.16 mg l(-1)). Based on the experimental data collected, the treatment technologies using chemical precipitation and ultrafiltration were applied to the wastewater. Both processes could effectively remove InP particles from the wastewater, however the coagulants in chemical precipitation introduced other ionic contents into the process resulting in difficulties of water recycling in the later stage. In comparison, ultrafiltration was more promising for InP wastewater treatment and recycling. Based on the results of this study, a full-scale UF system was built in a local semiconductor plant and it has successfully reclaimed water from the InP wastes for the past six months without any quality issue being raised.

The influence of the fixed negative charges on mechanical and electrical behaviors of articular cartilage under unconfined compression.

Unconfined compression test has been frequently used to study the mechanical behaviors of articular cartilage, both theoretically and experimentally. It has also been used in explant and gel-cell-complex studies in tissue engineering. In biphasic and poroelastic theories, the effect of charges fixed on the proteoglycan macromolecules in articular cartilage is embodied in the apparent compressive Young's modulus and the apparent Poisson's ratio of the tissue, and the fluid pressure is considered to be the portion above the osmotic pressure. In order to understand how proteoglycan fixed charges might affect the mechanical behaviors of articular cartilage, and in order to predict the osmotic pressure and electric fields inside the tissue in this experimental configuration, it is necessary to use a model that explicitly takes into account the charged nature of the tissue and the flow of ions within its porous interstices. In this paper, we used a finite element model based on the triphasic theory to study how fixed charges in the porous-permeable soft tissue can modulate its mechanical and electrochemical responses under a step displacement in unconfined compression. The results from finite element calculations showed that: 1) A charged tissue always supports a larger load than an uncharged tissue of the same intrinsic elastic moduli. 2) The apparent Young's modulus (the ratio of the equilibrium axial stress to the axial strain) is always greater than the intrinsic Young's modulus of an uncharged tissue. 3) The apparent Poisson's ratio (the negative ratio of the lateral strain to the axial strain) is always larger than the intrinsic Poisson's ratio of an uncharged tissue. 4) Load support derives from three sources: intrinsic matrix stiffness, hydraulic pressure and osmotic pressure. Under the unconfined compression, the Donnan osmotic pressure can constitute between 13%-22% of the total load support at equilibrium. 5) During the stress-relaxation process following the initial instant of loading, the diffusion potential (due to the gradient of the fixed charge density and the associated gradient of ion concentrations) and the streaming potential (due to fluid convection) compete against each other. Within the physiological range of material parameters, the polarity of the electric potential depends on both the mechanical properties and the fixed charge density (FCD) of the tissue. For softer tissues, the diffusion effects dominate the electromechanical response, while for stiffer tissues, the streaming potential dominates this response. 6) Fixed charges do not affect the instantaneous strain field relative to the initial equilibrium state. However, there is a sudden increase in the fluid pressure above the initial equilibrium osmotic pressure. These new findings are relevant and necessary for the understanding of cartilage mechanics, cartilage biosynthesis, electromechanical signal transduction by chondrocytes, and tissue engineering.

Characteristics of coagulation-flocculation of humic acid with effective performance of polymeric flocculant and inorganic coagulant.

Ferric chloride and aluminium sulphate as coagulants and positive charged flocculants PDDMAC ((PDDMAC = poly (diallyldimethylammonium chloride) were used for pre-treatment of water and wastewater for removing humic substance prior to RO membrane filtration. It was found that a combination of flocculant and coagulant enhanced the coagulation-flocculation process and humic acid removal. The optimum conditions of coagulation-flocculation were established in reference to the ratio of humic acid and coagulant. Zeta potential and the ratio of E4/E6 were investigated to explore the possible micro-mechanisms of coagulation-flocculation. The ratios of E4/E6 show the molecular size variations using different coagulants and flocculants, which are expected to benefit membrane-fouling control.

A submerged tubular ceramic membrane bioreactor for high strength wastewater treatment.

A 4 L submerged tubular ceramic membrane bioreactor (MBR) was applied in laboratory scale to treat 2,400 mg-COD/L high strength wastewater. A prolonged sludge retention time (SRT) of 200 day, in contrast to the conventional SRT of 5 to 15 days, was explored in this study, aiming to reduce substantially the amount of disposed sludge. The MBR system was operated for a period of 142 days in four runs, differentiated by specific oxygen utilization rate (SOUR) and hydraulic retention time (HRT). It was found that the MBR system produced more than 99% of suspended solid reduction. Mixed liquor suspended solids (MLSS) was found to be adversely proportional to HRT, and in general higher than the value from a conventional wastewater treatment plant. A chemical oxygen demand (COD) removal efficiency was achieved as high as 98% in Run 1, when SOUR was in the range of 100-200 mg-O/g-MLVSS/hr. Unexpectedly, the COD removal efficiency in Run 2 to 4 was higher than 92%, on average, where higher HRT and abnormally low SOUR of 20-30 mg-O/g-MLVSS/hr prevailed. It was noted that the ceramic membrane presented a significant soluble nutrient rejection when the microbial metabolism of biological treatment broke down.

Operational factors of submerged inorganic membrane bioreactor for organic wastewater treatment: sludge concentration and aeration rate.

Various sludge concentrations and aeration rates were evaluated to find the optimal operation condition of a submerged ceramic membrane filtration system. 5.6 g/L of sludge was diluted with water to concentrations of 2.8 g/L and 1.4 g/L, and the three sludge concentrations were compared in terms of titration characteristics such as pressure and filtrate flux. Flux was at the highest value of about 30 L/m2 x hr at 50 kPa when sludge concentration was 1.4 g/L. In contrast, when sludge concentrations increased to 2.8 g/L and 5.6 g/L, the flux at 50 kPa decreased significantly to 18 L/m2 x hr and 10 L/m2 x hr, respectively. It was concluded that the sludge concentration directly affected the filtration efficiency, and low sludge concentration was suitable for improving filtration efficiency. Adjusting the aeration rate from 2 L/min to 4 L/min at 5.6 g/L of sludge and 50 kPa of pressure increased flux from 10 L/m2 x hr to 13 L/m2 x hr. It was obvious that the vigorous aeration improved the filtration efficiency, but the aeration rate did not seem to be high enough to maintain flux lower than critical flux.

Photocatalytic oxidation technology for humic acid removal using a nano-structured TiO2/Fe2O3 catalyst.

A novel TiO2 coated haematite photocatalyst was prepared and used for removal of colored humic acids from wastewater in an UV bubble photocatalytic reactor. XRD analysis confirmed that nano-size anatase crystals of TiO2 were formed after calcination at 480 degrees C. SEM results revealed that nano-size particles of TiO2 were uniformly coated on the surface of Fe2O3 to form a bulk of nano-structured photocatalyst Fe2O3/TiO2. The porous catalyst had a BET surface area of 168 m2/g. Both the color and total organic carbon (TOC) conversion versus the residence time were measured at various conditions. The effects of pH value, catalyst loaded, initial humic acid concentration and reaction temperature on conversion were monitored. The experimental results proved that the photocatalytic oxidation process was not temperature sensitive and the optimum catalyst loading was found to be 0.4 g/l. Degradation and decolorization of humic acids have higher efficiency in acidic medium and at low initial humic acid concentration. The new catalyst was effective in removing TOC at 61.58% and color400 at 93.25% at 180 minutes illumination time and for 20 mg/l neutral humic acid aqueous solution. The kinetic analysis showed thatthe rate of photocatalytic degradation of humic acids obeyed the first order reaction kinetics.

Electrical signals for chondrocytes in cartilage.

An important step toward understanding signal transduction mechanisms modulating cellular activities is the accurate predictions of the mechanical and electro-chemical environment of the cells in well-defined experimental configurations. Although electro-kinetic phenomena in cartilage are well known, few studies have focused on the electric field inside the tissue. In this paper, we present some of our recent calculations of the electric field inside a layer of cartilage (with and without cells) in an open circuit one-dimensional (1D) stress relaxation experiment. The electric field inside the tissue derives from the streaming effects (streaming potential) and the diffusion effect (diffusion potential). Our results show that, for realistic cartilage material parameters, due to deformation-induced inhomogeneity of the fixed charge density, the two potentials compete against each other. For softer tissue, the diffusion potential may dominate over the streaming potential and vice versa for stiffer tissue. These results demonstrate that for proper interpretation of the mechano-electrochemical signal transduction mechanisms, one must not ignore the diffusion potential.

Recovery of heavy metals and stabilization of spent hydrotreating catalyst using a glass-ceramic matrix.

Chemical analysis of spent Co/Mo/gamma Al(2)O(3) catalyst revealed the presence of carbon, molybdenum, sulfur, vanadium and cobalt at levels of 16.0, 10.9, 7.3, 4.6 and 4.0 wt.%, respectively. It was found that calcination at 500 degrees C provides an effective solution for the removal of carbon and sulfur and this generates the oxide form of the heavy metals. The removal of these heavy metals can be achieved through a two-stage leaching process. During the first stage, in which concentrated ammonia is used and it has been found that this process can be successful in removing as much as 83% (w/v) Mo. In a second stage, it was found that using 10% (v/v) of sulfuric acid, it was possible to account for up to 77% (w/v) Co and 4% (w/v) Mo removal. Leaching test results indicated that the vanadium present in the heated spent catalyst was almost stabilized but the molybdenum and cobalt were not. The combination of two solid wastes, ladle furnace slag (LFS) and treated residue of spent catalyst, could be used for making a high value-added anorthite glass-ceramic materials. Further leaching tests showed that ceramic glass materials provided a very effective method of Co, Mo and V heavy metals stabilization resulting in a product with a possible commercial value.

Removal of color substances using photocatalytic oxidation for membrane filtration processes.

This study aims to remove the color substances, which normally cause difficulties in membrane filtration processes due to fouling using heterogeneous UV/TiO2/H2O2 reactor. It is confirmed that the technique used in this study was effective to remove TOC at 38% and color400 at 89% within 150-min irradiation. The experiment results showed that low concentrations of hydrogen peroxide dosage (less than 0.016 M) to UV/TiO2 system accelerated the TOC and Color400 removal rate from 9% to 38% and 40% to 89% respectively, while over-dosage made this positive effect decline. The humic acid solution treated by photo catalytic oxidation in UV/TiO2/H2O2 reactor did not change the zeta potential on membrane surface and membrane rejection rate.

Stabilization of heavy metals on spent fluid catalytic cracking catalyst using marine clay.

Spent fluid catalytic cracking catalyst is a hazardous solid waste generated by petroleum refineries containing vanadium and nickel. The marine clay was used as a matrix to stabilize vanadium and nickel and produce bricks which were then fired at various temperatures. TCLP leaching tests indicated that stabilizing brick had low metal leaching, with a maximum of 6.4 mg/l for vanadium and 19.8 microg/l for nickel. Compressive strength of stabilizing brick was found to range between 20 N/mm2 and 47 N/mm2. It is believed that stabilization and encapsulation mechanisms are responsible for the stabilization of vanadium and nickel. Encapsulation is a process whereby the marine clay matrix forms a physical barrier around the heavy metals which are thus prevented from leaching out into the environment. Incorporation involves the formation of bonds between the marine clay matrix and the heavy metals which thus become incorporated in the clay microstructure.

[Determination of impurity elements in high purity gold using ICP-AES method after matrix extraction and separation].

A system for separation of trace impurity elements (Cd, Cr, Cu, Fe, Mn, Ni, Pb, Pt) from large amounts of matrix element gold is proposed in this paper. It is based on the MIBK extraction. The effect of pH to the extraction is studied, the final measuring solution is effectively 10% hydrochloric acid. The recovery of elements is between 93.3%-100% under this acidity after the first extraction. Content of trace elements of 99.99% gold is in the range 0.1-20 micrograms.g-1.