The predictors of short and long term urinary continence recovery after laparoscopic radical prostatectomy: a single cancer center report in China.

PURPOSE: To evaluate the predictors for short and long term urinary continence (UC) recovery after laparoscopic radical prostatectomy (LRP) from clinical and oncological variables. METHODS: We retrospectively collected data from 142 prostate cancer patients who underwent LRP between September 2014 and June 2021 at a tumor specialist diagnosis and treatment center in China. The rate of post-prostatectomy incontinence (PPI) was evaluated from immediate and at 3, 6 and 12 mo after LRP, and UC was defined as the use of no or one safety pad. Sixteen clinical and oncological variables were analyzed by univariate and multivariate regression analysis to determine whether they were associated with short (3 mo) or long term (12 mo) UC recovery after LRP. RESULTS: After eliminating patients who were lost to follow-up, 129 patients were eventually included. The mean ± SD age was 68 ± 6.3 years. The UC rates of immediate, 3, 6 and 12 mo after the operation were 27.9%, 54.3%, 75.2% and 88.4%, respectively. Multivariate analyses revealed that membranous urethral length (MUL) was a protective predictor of UC after catheter extraction(P < 0.001), and at 3 mo (P < 0.001), 6 mo (P < 0.001) and 12 mo (P = 0.009) after surgery. CONCLUSION: MUL is a significant independent factor that can contribute to short and long term UC recovery post-LRP, which may assist clinicians and their patients in counseling of treatment.

Research progress of persulfate activation technology.

Persulfate-based advanced oxidation processes (PS-AOPs) have been widely investigated by academia and industry due to their high efficiency and selectivity for the removal of trace organic pollutants from complex water substrates. PS-AOPs have been extensively studied for the degradation of pesticides, drugs, halogen compounds, dyes, and other pollutants. Utilizing bibliometric statistics, this review presents a comprehensive overview of persulfate-based advanced oxidation technology research over the past decade. The number of published articles about persulfate activation has steadily increased during this time, reflecting extensive international collaboration. Furthermore, this review introduces the most widely employed strategies for persulfate activation reported in the past 10 years, including carbon material activation, photocatalysis, transition metal activation, electrochemical activation, ultrasonic activation, thermal activation, and alkali activation. Next, the potential activation mechanisms and influencing factors, such as persulfate dosage during activation, are discussed. Finally, the application of PS-AOPs in wastewater treatment and in situ groundwater treatment is examined. This review summarizes the previously reported experiences of persulfate-based advanced oxidation technology and presents the current application status of PS-AOPs in organic pollution removal, with the aim of avoiding misunderstandings and providing a solid foundation for future research on the removal of organic pollutants.

Hydrolysis of sulfamethoxazole in the hyporheic zone: kinetics, factors and pathways.

ABSTRACTIt is unknown how antibiotics would behave after entering the hyporheic zone (HZ), which is an area where groundwater and surface water alternate continuously. In this study, the hydrolysis process in the HZ was investigated based on the intermediates identified by HPLC-Q-TOF-MS and FTIR, and the active sites of sulfamethoxazole (SMX) were predicted by density functional theory (DFT). The results showed that the hydrolysis rate of SMX during surface water recharged groundwater reached 38.94%, and the contribution rate of hydroxyl radicals reached 48.35%. In neutral and alkaline environments, SMX hydrolysed more quickly. This is due to the fact that ·OH, as the main precursor of OH-, is much higher in quantity under alkaline conditions. Inorganic anions such as NO3-, HCO3- and CO32- may inhibit the hydrolysis of SMX by eliminating the reactive oxygen species generated in the HZ. In the process of groundwater recharging to surface water, the concentration of dissolved oxygen (DO) and the rate of SMX hydrolysis gradually reduced. Nitrification, hydroxylation and polymerisation are the main hydrolysis pathways of SMX. The hydrolysis products of SMX in the HZ are more plentiful and have a higher hydrolysis rate compared to the single oxygen environment. The study on the hydrolysis mechanism of SMX in this paper will provide a theoretical basis for the treatment of antibiotic pollution.

Temporal dynamic of antibiotic resistance genes in the Zaohe-Weihe hyporheic zone: driven by oxygen and bacterial community.

The widespread spread of antibiotic resistance genes (ARGs) in hyporheic zone (HZ) has become an emerging environmental problem due to their potentially harmful nature. In this research, three different oxygen treatment systems were set up to study the effects of oxygen changes on the abundance of ARGs in the HZ. In addition, the effects of temperature and salinity on ARGs were investigated under aerobic and anaerobic systems, respectively. The bacterial community composition of sediment samples and the relationship with ARGs were analyzed. The explanation ratio and causality of the driving factors affecting ARGs were analyzed using variation partitioning analysis (VPA) and structural equation model (SEM). The relative abundance of ARGs and mobile genetic elements (MGEs) in the anaerobic system increased significantly, which was higher than that in the aerobic system and the aerobic-anaerobic interaction system. The experiment of salinity and temperature also further proved this result. There were many bacterial communities that affected tetracycline and sulfonamide ARGs in sediments, and these host bacteria are mainly concentrated in Proteobacteria, Firmicutes and Bacteroidetes. VPA and SEM further revealed that the abundance of ARGs was mainly influenced by changes in bacterial communities and oxygen conditions, and horizontal gene transfer (HGT) of MGEs also had a positive effect on the spread of ARGs. Those findings suggest that complex oxygen conditions in the HZ alter bacterial communities and promote MGEs-mediated horizontal transfer, which together lead to the spread of ARGs. This study has value as a reference for formulating effective strategies to minimize the propagation of ARGs in underground environment.

Enhancement of Congo Red-Neomycin Resonance Rayleigh Scattering by Dodecyl Trimethyl Ammonium Bromide and its Application.

A simple, rapid, and convenient method for the determination of neomycin based on the ion association method was proposed. In Britton-Robinson buffer solution, neomycin could react with Congo red to form an ionic association, which in turn reacted with dodecyl trimethyl ammonium bromide to form a ternary ionic association. The three were combined in a 1 : 1 : 1 ratio, which significantly enhanced the resonant Rayleigh scattering intensity at 468 nm. The obtained resonant Rayleigh scattering sensor showed a linear relationship with neomycin in the range of 0.07∼1 µg·mL-1. The limit of detection was 0.02 µg·mL-1, and the limit of quantification was 0.037 µg·mL-1. The experimental conditions were optimized. The method was verified based on the ICH rule. The established method could be applied to the analysis of the acceptable recovery rate of neomycin in powdered veterinary drugs.

Applying resonance Rayleigh scattering and spectrofluorimetric techniques for the selective determination of neomycin sulfate using Congo red as a probe: Applications for wastewater analysis.

Two simple, sensitive, and low-cost fluorescence spectroscopy methods for neomycin (NEO) detection were developed. Both methods were based on the interaction between NEO and Congo red (CR) in acidic buffer medium to form an ion-association complex. The quenching effect of the formed ion-association complex on the fluorescence of CR at 421 nm is a basic principle of fluorescence analysis, whilst the resonance Rayleigh scattering (RRS) method was used to enhance the resonance Rayleigh scattering spectrum at 384 nm by adding NEO. Experimental conditions such as pH, temperature, reaction time, CR concentration, and the ionic strength of the two methods were investigated and optimized. In addition, the effect of common coexisting substances on the method was tested and the results showed good selectivity. The composition of ion-association complexes, the reaction mechanism, and reasons for the enhanced intensity of RRS are discussed. Under optimum conditions, the responses of the fluorescence spectrophotometry and RRS methods showed good linearity with NEO concentrations in the range 0.2-3.0 µg ml-1 and 0.1-3.0 µg ml-1 , respectively. The detection limits of fluorescence spectrophotometry and RRS spectroscopy techniques were 0.02 µg ml-1 and 0.01 µg ml-1 , respectively. Finally, the two methods were applied to the analysis of wastewater and the results were satisfactory.

Establishment and evaluation of ectopic and orthotopic prostate cancer models using cell sheet technology.

BACKGROUND: The traditional prostate cancer (PCa) model is established by injecting cell suspension and is associated with a low tumor formation rate. Cell sheet technology is one of the advancements in tissue engineering for 3D cell-based therapy. In this study, we established ectopic and orthotopic PCa models by cell sheet technology, and then compared the efficiency of tumor formation with cell suspension injection. METHODS: DU145 cells were seeded on 35 mm temperature-sensitive dishes to form PCa cell sheets, while the cell suspension with the same cell density was prepared. After transplanting into the nude mice, the tumor volumes were measured every 3 days and the tumor growth curves were conducted. At the time points of 2 weeks and 4 weeks after the transplantation, magnetic resonance imaging (MRI) was used to evaluate the transplanting site and distant metastasis. Finally, the mice were sacrificed, and the related tissues were harvested for the further histological evaluation. RESULTS: The orthotopic tumor formation rate of the cell sheet injection group was obviously better than that in cell suspension injection group (100% vs 67%). Compared with cell suspension injection, the tumors of DU145 cell sheet fragments injection had the higher density of micro-vessels, more collagen deposition, and lower apoptosis rate. There was no evidence of metastasis in forelimb, lung and liver was found by MRI and histological tests. CONCLUSION: We successfully cultured the DU145 cell sheet and can be used to establish ectopic and orthotopic PCa tumor-bearing models, which provide an application potential for preclinical drug development, drug-resistance mechanisms and patient individualized therapy.

Hydrolysis of norfloxacin in the hyporheic zone: kinetics and pathways.

Understanding the hydrolysis behavior and pathway of norfloxacin (NOR) in the hyporheic zone (HZ) is important for predicting its environmental persistence. Therefore, the effects of different environmental factors on NOR hydrolysis were investigated, and the hydrolysis pathway of NOR in the HZ was determined by DFT calculations and UPLC/TOF-MS. The hydrolysis process of NOR was consistent with the first-order kinetic. The experiment of environmental factors showed that DO was an important factor to affect NOR hydrolysis, and its hydrolysis rate was positively correlated with DO concentration. The superoxide radical (·O2-) was the main active species for NOR hydrolysis. The hydrolysis rates of NOR under neutral and alkaline conditions were higher than that under acidic conditions in both aerobic and anoxic environments. The ions of Ca2+, Mg2+, HCO3-, CO32-, and NO3- in simulated water samples inhibited the hydrolysis of NOR, while Cl- promoted its hydrolysis. In addition, the electronegativity of NOR was determined by DFT calculations, and it was speculated that the active sites of NOR hydrolysis were mainly located in the piperazine ring and quinolone ring. The main hydrolysis pathway of NOR in aerobic environment was piperazine ring cracking and quinolone ring decomposition, and that in anoxic environment was piperazine ring cracking. The results are of great significance to evaluate the environmental fate of NOR in the HZ and provide a theoretical basis for further understanding the degradation and governance of fluoroquinolones in water environment.

New insights into the interaction between dissolved organic matter and different types of antibiotics, oxytetracycline and sulfadiazine: Multi-spectroscopic methods and density functional theory calculations.

Dissolved organic matter (DOM) is composed of numerous fluorescent components. It is an indispensable parameter to affect the environmental fate of antibiotics in various ways. To assess the migration of antibiotics in environment compartments, it is crucial to understand the binding mechanism between DOM and antibiotics. How a particular component in DOM interacts with coexistence antibiotics is not still fully understood. Therefore, in the present study, interactions of two antibiotics oxytetracycline (OTC) and sulfadiazine (SD) with humic acid (HA) and L-tryptophan (L-Trp) which were representative DOM components, were investigated by multispectral techniques and density functional theory (DFT) calculations. The fluorescence quenching mechanism was static quenching. In the binding process, the quenching ability of OTC was stronger than that of SD in HA, which was the same as in L-Trp. DFT calculations were applied to confirm a stronger interaction between OTC and HA or L-Trp than SD. Meanwhile, analyzing the binding sequence by two-dimensional correlation spectroscopy (2D-COS), a humic-like substance bound antibiotics was earlier than a protein-like substance. In HA system, the combination of two antibiotics had a synergistic effect on HA quenching. In L-Trp system, the quenching relationship between the two antibiotics and L-Trp was antagonistic. The FTIR spectra showed that hydroxyl and amide were involved in the binding process of individual DOM components with OTC and SD. The work will help to further understand the behavior of coexistence antibiotics in the environment.

Spatial distribution of antibiotic resistance genes of the Zaohe-Weihe Rivers, China: exerting a bottleneck in the hyporheic zone.

The hyporheic zone (HZ) is an active biogeochemical region where groundwater and surface water mix and a potential reservoir for antibiotic resistance genes (ARGs). In this paper, the relative abundance and spatial distribution of ARGs in the HZ media were investigated, taking into consideration both the five speciation of six metals and the local characteristics. The samples of surface water, groundwater, and sediment were collected from Zaohe-Weihe Rivers of Xi'an City, which is a representative city with characteristics of the northwest region of China. Of 271 ARGs associated with 9 antibiotics, 228 ARGs were detected, with a total detection rate of 84%. Sulfonamide and aminoglycoside ARGs were the dominant types of ARGs. The top 6 ARGs and mobile genetic elements (MGEs) in terms of abundance were tnpA-04, cepA, sul1, aadA2-03, sul2 and intI1. The results of principal component analysis (PCA) showed that the distribution characteristics of ARGs were not associated with the sampling sites but with the environmental medias. Similarity in the water phases and significant differences in the water and sediment phases were found. The redundancy analysis (RDA) identified the key factors controlling ARG pollution, including dissolved oxygen (DO) in surface water, total nitrogen (TN) in groundwater, and total organic carbon (TOC) in sediment. In terms of the speciation of heavy metals, we further revealed the promotion effect between ARGs and heavy metals, especially the residual fraction of Ni. In terms of horizontal transfer mechanism, ARGs were significantly correlated with tnpA-03 in water phase and tnpA-04 in sediment. In the three media, intI1 and ARGs all show a significant correlation. These findings showed that hyporheic zone exerted a bottleneck effect on the distribution and transfer of ARGs.

Evaluation of 18F-PSMA-1007 PET/CT in prostate cancer patients with biochemical recurrence after radical prostatectomy.

PURPOSE: Prostate-specific membrane antigen (PSMA) ligands targeting has shown promising results in staging of prostate cancer (PCa). The aim of present study was to evaluate the value of 18F-PSMA-1007 PET/CT in PCa patients with biochemical recurrence. METHODS: 71 patients with PCa after radical prostatectomy (RP) were included in the present study. Median prostate-specific antigen (PSA) level was 1.27 ng/mL (range 0.01-67.40 ng/mL, n = 69). All patients underwent whole-body PET/CT imaging after injection of 333±38 MBq 18F-PSMA-1007. The distribution of PSMA-positive lesions was assessed. The influence of PSA level, androgen deprivation therapy and primary Gleason score on PSMA-positive finding and uptake of 18F-PSMA-1007 were evaluated. RESULTS: 56 (79%) patients showed at least one pathological finding on 18F-PSMA-1007 PET/CT. The rates of positive scans were 50%, 80%, 100%, 100% among patients with PSA levels ≤0.5, 0.51-1.0, 1.1-2.0 and >2.0 ng/mL, respectively. The median Gleason score was 8 (range 7-10), and higher Gleason score (≤7 vs. ≥8) leads to higher detection rates (58.3% (14/24) vs. 88.9% (32/36), P = 0.006). The median SUVmax of positive findings in patients with PSA levels ≤0.5, 0.51-1.0, 1.1-2.0 and >2.0 ng/mL were 4.51, 4.27, 11.50 and 14.08, respectively. The median SUVmax in patients with PSA level >2.0 ng/mL was significantly higher than that in patients with PSA ≤2.0 ng/mL (14.08 vs. 6.13, P<0.001). CONCLUSION: 18F-PSMA-1007 PET/CT demonstrated a high detection rate for patients with a raised PSA level after radical prostatectomy even in patients with extremely low PSA level (eg. PSA level ≤0.5 ng/mL), which was essential for further clinical management for PCa patients.

Retroperitoneal laparoscopic partial nephrectomy for unilateral synchronous multifocal renal carcinoma with different pathological types: A case report.

BACKGROUND: The majority of renal cell carcinomas are single lesions; unilateral synchronous multifocal renal carcinoma (USMRC) is rarely reported and poses a treatment challenge for urological oncologists. CASE SUMMARY: A 56-year-old man was hospitalized for pain and discomfort in the right kidney area for 6 d. Contrast-enhanced computed tomography demonstrated cT1a renal tumors at the lower pole of the right kidney and a cT1b renal tumor at the middle dorsal portion of the right kidney. The patient underwent retroperitoneal laparoscopic partial nephrectomy (RLPN). There were no complications peri-operatively. Histopathology revealed a low-grade, pathologic stage T1a (pT1a), clear cell renal cell carcinoma at the lower pole of the right kidney and a pT1b, chromophobe renal cell carcinoma at the middle dorsal portion of the right kidney. No tumor bed recurrence or metastasis was observed on imaging and his renal function remained stable during the 12-mo follow-up period. CONCLUSION: RLPN is a safe, effective, and feasible for the management of USMRC, which can obtain equivalent oncological results with optimal renal function preservation.

Assessment of ecological environment impact in highway construction activities with improved group AHP-FCE approach in China.

Highway construction is time consuming and complicated. Various environmental issues can be encountered during this process. Therefore, it is necessary to assess the impact of ecologic environment in highway construction. However, the traditional assessment approaches paid more attention to the environmental factors rather than the ecological problems, and the weights of evaluation indexes were assigned with relatively average values, which cannot comprehensively and accurately to assess the impact of ecological environment in highway construction. In order to solve these problems, this paper established a new model to combine improved group AHP and FCE. A total of six main factors and 22 sub-factors from three aspects of social, ecological, and natural environment were identified. The model and index system were applied to the ecological environment impact assessment of the highway from the city of Hanzhong to Lueyang County section in Shaanxi Province, and compared with traditional fuzzy AHP approach to verify the feasibility of this model. The results showed that only the ranking of social and ecological factor changed when comparing with the traditional approach. The weight of social factor determined by the improved approach was 0.2835, while that of the traditional approach was only 0.2365, and the weight difference was 0.047. This improved approach highlighted the importance of social factor and overcame the equal weight distribution of traditional approach, which made the overall weight ratio distribution more reasonable and objective. The comprehensive assessment result was 0.3482, which was in line with the "general impact" level. This was consistent with the actual situation of highway construction. The improved group AHP-FCE model could be used successfully for assessing the impact of the ecological environment in highway construction, and it had good applicability and popularization value in ecological environment assessment.

Contamination Level, Distribution Characteristics, and Ecotoxicity of Tetrabromobisphenol A in Water and Sediment from Weihe River Basin, China.

Tetrabromobisphenol A (TBBPA) is a brominated flame retardant, which is widely present in the various environmental and biological media. The knowledge on the contamination of TBBPA in Weihe River Basin is still limited. In order to know the pollution level and distribution of tetrabromobisphenol A (TBBPA) in the Weihe River Basin, a total of 34 sediment samples and 36 water samples were collected from the main stream and tributaries of the WeiHe River Basin, and the concentration of TBBPA in the samples was analyzed by high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS). The detection frequency of TBBPA in sediments and water samples was 61.8% and 27.8%, respectively; the TBBPA concentrations in sediments and water samples were in the range of not detected (N.D.)-3.889 ng/g (mean value of 0.283 ng/g) and N.D-12.279 ng/L (mean value of 0.937 ng/L), respectively. Compared with other areas in China, the residues of TBBPA in the Weihe River Basin were at a relatively low level. The spatial distributions of TBBPA in surface sediments and water indicated that the local point-input was their major source. This is related to the proximity of some sampling sites to industrial areas and domestic sewage discharge areas. The insignificant correlation between TBBPA and total organic carbon (TOC) indicated that TBBPA in sediments is not only influenced by TOC but also affected by atmosphere and land input, wet deposition, and long-distance transmission. The potential risks posed by TBBPA in water and sediment were characterized using the risk quotient (RQ) method. The calculated RQ for TBBPA was less than 0.01, showing that the ecological risk due to TBBPA was quite low for aquatic organisms.

Adsorption Characteristics of Oxytetracycline by Different Fractions of the Organic Matter from Humus Soil: Insight from Internal Structure and Composition.

For minimizing the transport of antibiotics to groundwater, the migration of antibiotics in soils should be investigated. Soil organic matter can affect the migration of antibiotics. To date, the influence of aromatics and aliphatic content of organic matter on the adsorption of antibiotics has been controversial. To better understand the reaction mechanism of soil organic matter with antibiotics, this study investigated the adsorption of oxytetracycline (OTC) by humus soils (HOS) and their fractions. HOS were sequentially fractionated into four organic fractions, including the removal of dissolved organic matter (HRDOM), removal of minerals (HRM), removal of free fat (HRLF), and nonhydrolyzable organic carbon (HNHC). Moreover, batch experiments revealed that adsorption capacity was ordered by HNHC > HOS > HRDOM > HRLF > HRM. SEM images and N2 adsorption/desorption isotherms indicate that adsorption capacity is independent of the external structure. However, adsorption capacity is related to the internal structure and composition. Combination analysis with elemental composition and infrared spectroscopy showed that the adsorption capacity of HRM, HRLF, and HNHC had a good positive correlation with aromaticity, but a negative correlation with polarity and hydrophilicity. Additionally, the rule of binding affinity between OTC and functional groups with different properties was summarized as aromatic > polarity > hydrophilic.

Hydrophobic and Anti-Fouling Performance of Surface on Parabolic Morphology.

The hydrophobicity and anti-fouling properties of materials have important application value in industrial and agricultural production and people's daily life. To study the relationship between the unit width L0 of the parabolic hydrophobic material and the hydrophobicity and anti-fouling properties, the rough surface structure of the parabolic with different widths was prepared by grinding with different SiC sandpapers, and further, to obtain hydrophobic materials through chemical oxidation and chemical etching, and modification with stearic acid (SA). The morphology, surface wetting and anti-fouling properties of the modified materials were characterized by SEM and contact angle measurement. The oil-water separation performance and self-cleaning performance of the materials were explored. The surface of the modified copper sheet forms a rough structure similar to a paraboloid. When ground with 1500 grit SiC sandpaper, it is more conducive to increase the hydrophobicity of the copper sheet surface and increase the contact angle of water droplets on the copper surface. Additionally, the self-cleaning and anti-fouling experiments showed that as L0 decreases, copper sheets were less able to stick to foreign things such as soil, and the better the self-cleaning and anti-fouling performance was. Based on the oil-water separation experiment of copper mesh, the lower L0 has a higher oil-water separation efficiency. The results showed that material with parabolic morphology has great self-cleaning, anti-fouling, and oil-water separation performance. The smaller the L0 was, the larger the contact angle and the better hydrophobic performance and self-cleaning performance were.

Performance evaluation of treating oil-containing restaurant wastewater in microbial fuel cell using in situ graphene/polyaniline modified titanium oxide anode.

Most studies conducted nowadays to boost electrode performance in microbial fuel cell (MFC) have focused on carbonaceous materials. The titanium suboxides (Ti4O7, TS) are able to provide a new alternative for achieving better performance in MFC and have been tested and demonstrated in this study. The Ti4O7 electrode with high electrochemical activity was modified by graphene/polyaniline by the constant potential method. Electrogenic microorganisms were more conducive to adhere to the anode electrode due to the presence of graphene/polyaniline. The MFC reactor with polyaniline /graphene modified TS (TSGP) anode achieves the highest voltage with 980 mV, and produces a peak power density of 2073 mW/m2, which is 2.9 and 12.7 times of those with the carbon cloth anode, respectively, at the 1000â€…Ω external resistance. In addition, this study evaluates the effects of anolyte conductivity, pH, and COD on the treatment of oil-containing restaurant wastewater (OCRW) in MFC using TSGP anode. The OCRW amended with 120 mS/cm obtains the lowest internal resistance (160.3 Ω). Increasing the anodic pH, gradually from acidic (pH 5.5) to alkaline conditions (pH 8.0), resulted in a gradual increase in maximum power density to 576.4 mW/m2 and a decrease in internal cell resistance to 203.7 Ω. The MFC at the COD 1500 mg/L could obtain steady-state output voltage during 103 h while removing up to 65.2% of the COD of the OCRW.

Effect of dissolved organic matter on adsorption of sediments to Oxytetracycline: An insight from zeta potential and DLVO theory.

To reveal the adsorption mechanism of sediment to antibiotics with the presence of dissolved organic matter (DOM), batch experiments were carried out by oxytetracycline (OTC) on sediments with decayed plants (PDOM) and composted chicken manure (MDOM), and the zeta potential in the system before and after adsorption was measured. Results showed that the PDOM promoted the adsorption process, while the MDOM inhibited the adsorption. Adding PDOM, the change of zeta potential (Δζ) increased by 40.08% for first terrace sediments (FT) and 63.98% for riverbed sediments (RB), respectively; meanwhile, MDOM decreased by 20.04% for FT and 28.39% for RB, respectively. The results of kinetic fitting models of replacing the adsorption amount with Δζ were consistent with the initial. It indicated that there was a positive correlation between the adsorption amount and Δζ, and the zeta potential can be used to quickly judge the degree of adsorption process. The Derjaguin-Landau-Verwey-Overbeek (DLVO) theory describes the interactions of sediment particles. In terms of adsorption amount, zeta potential (absolute value) and total interaction energy all followed the order: RB > FT, RB-PDOM > FT-PDOM, and RB-MDOM > FT-MDOM. The more negative the zeta potential is, the better the dispersion of the particles is. Stronger repulsion is more conducive to adsorbing positively charged OTC. The site energy distribution theory further explained that the distribution of adsorption site in the various states of sediments increased while adding the PDOM and decreased while adding the MDOM.

Adsorption behavior and selectivity mechanism of flotation reagents applied in ternary plastic mixtures.

Plastic flotation attracts increasing attention in the process of recycling and will bring potential application in industry after theoretical perfection. For a separated ternary system of polyethylene terephthalate (PET), polyvinyl chloride (PVC) and polyethylene (PE), adsorption behavior and selectivity mechanism of flotation reagents were investigated by multi-characterization tests and batch equilibrium adsorption method. Quantitative adsorption results indicate that frother polyethylene glycol (PEG) only acts on gas and liquid phases in the flotation system with negligible adsorption capacity onto solid phase. For depressant sodium lignosulphonate (SL), the pseudo-first-order and Langmuir isotherm models are suitable for corresponding kinetic and equilibrium data of PET or PVC. Thermodynamic parameters further indicate that the adsorption of SL is a spontaneous and endothermic process, which neither belongs to the pure physisorption nor to the pure chemisorption. Adsorption models of SL were established based on hydrogen bond, with three clear bonding types (OH…π*, OH…O, and OH…Cl). Selectivity mechanism can be attributed to the selective hydrogen bond acceptors and donors, which are provided by specific plastic and depressant, respectively. In the light of these theoretical fundings, new targeted reagents or pre-treatments are expected to be developed towards more complex flotation system.

Adsorption characteristics of oxytetracycline by different fractions of organic matter in sedimentary soil.

Sedimentary soil was selected as the original sample (SOS). The adsorption fractions were obtained by the removal of dissolved organic matter (SRDOM), removal of minerals (SRM), removal of free fat (SRLF), and removal of nonhydrolyzable organic carbon (SNHC) respectively to investigate the adsorption characteristic of oxytetracycline (OTC) by different fractions of organic matter in sedimentary soil. The adsorption mechanism was investigated by elemental analysis, infrared spectra, and UV-visible spectroscopy. The results showed that the DOM in the sedimentary soil inhibited the adsorption of OTC, but the adsorption of different fractions of organic matter was quite different. The sorption kinetics of OTC were fitted to the pseudo-second-order model and the adsorption capacity of each fraction was: SNHC≈SRDOM > SOS > SRLF> SRM. The adsorption processes of OTC by different fractions were spontaneous. Alkaline pH condition had an effect on the adsorption of four fractions except for SNHC, while neutral and acidic pH affects SOS and SRDOM more obviously, the SNHC fraction was almost free from pH varies. Mechanism analysis showed that the main factors determining the adsorption capacity were the aromaticity and polarity of organic matter fractions. For the organic matter-based fractions (SRM, SRLF, and SNHC), the adsorption coefficient was positively correlated with the aromaticity. Furthermore, for SOS and SRDOM based on inorganic minerals, it was not only related to aromaticity, but also the content and composition of inorganic minerals.