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1.
Gels ; 10(4)2024 Mar 26.
Article En | MEDLINE | ID: mdl-38667644

It was first discovered that the excellent gelation ability of tea saponin can be obtained by introducing long-chain alkyl groups of dodecanoyl chloride into the glycosyl portion with direct esterification. The modified dodecanoyl chloride-tea saponin (DC-TS) was successfully synthesized and characterized with NMR, MS, and FT-IR. The tests showed that the long-chain alkyl group was successfully introduced. Combined with SEM and X-ray diffraction patterns, we found that the stable lamellar shape gels of DC-TS were formed in a variety of solvents. More interestingly, organogel was also obtained by adjusting good solvent and poor solvent as mixed solvent. It is worth noting that the driving force of organogels is the combination of hydrogen bonding and the hydrophobic interaction of the introduced alkyl chains with the rigid backbone of pentacyclic triterpenes. The modified tea saponin, a natural green surfactant, was discovered to have gelation properties, which has broadened tea saponin's scope of application and made it more promising.

2.
Front Microbiol ; 15: 1352430, 2024.
Article En | MEDLINE | ID: mdl-38618484

In view of water and soil getting polluted by Pb(II), Zn(II), and other heavy metals in tailings and acid mine drainage (AMD), we explored the removal effect of sulfate-reducing bacteria (SRB) on Pb(II), Zn(II), and other pollutants in solution and tailings based on the microbial treatment technology. We used the scanning electron microscope-energy dispersive spectroscopy (SEM-EDS), X-ray diffraction (XRD), and X-ray fluorescence (XRF), to reveal the mechanism of SRB treatment of tailings. The results showed that SRB had a strong removal capacity for Zn(II) at 0-40 mg/L; however, Zn(II) at 60-100 mg/L inhibited the growth of SRB. Similarly, SRB exhibited a very strong ability to remove Pb(II) from the solution. At a Pb(II) concentration of 10-50 mg/L, its removal percentage by SRB was 100%. SRB treatment could effectively immobilize the pollutants leached from the tailings. With an increase in the amount of tailings added to each layer, the ability of SRB to treat the pollutants diminished. When 1 cm of tailingssand was added to each layer, SRB had the best effect on tailing sand treatment. After treatment, the immobilization rates of SO42-, Fe(III), Mn(II), Pb(II), Zn(II), Cu(II), and total Cr in the leachate of #1 tailing sand were 95.44%, 100%, 90.88%, 100%, 96.20%, 86.23%, and 93.34%, respectively. After the tailings were treated by SRB, although the tailings solidified into a cohesive mass from loose granular particles, their mechanical strength was <0.2 MPa. Desulfovibrio and Desulfohalotomaculum played the predominant roles in treating tailings by mixing SRB. The S2- and carbonate produced by mixing SRB during the treatment of tailings could metabolize sulfate by combining with the heavy metal ions released by the tailings to form FeS, MnS, ZnS, CuS, PbS, Cr2S3, CaCO3, MnCO3, and other precipitated particles. These particles were attached to the surface of the tailings, reducing the environmental pollution of the tailings in the water and soil around the mining area.

3.
Sci Rep ; 14(1): 9927, 2024 Apr 30.
Article En | MEDLINE | ID: mdl-38688999

Aiming at the acid mine drainage (AMD) in zinc, copper and other heavy metals treatment difficulties, severe pollution of soil and water environment and other problems. Through the ultrasonic precipitation method, this study prepared fly ash-loaded nano-FeS composites (nFeS-F). The effects of nFeS-F dosage, pH, stirring rate, reaction time and initial concentration of the solution on the adsorption of Zn(II) and Cu(II) were investigated. The data were fitted by Lagergren first and second-order kinetic equations, Internal diffusion equation, Langmuir and Freundlich isotherm models, and combined with SEM, TEM, FTIR, TGA, and XPS assays to reveal the mechanism of nFeS-F adsorption of Zn(II) and Cu(II). The results demonstrated that: The removal of Zn(II) and Cu(II) by nFeS-F could reach 83.36% and 70.40%, respectively (The dosage was 8 g/L, pH was 4, time was 150 min, and concentration was 100 mg/L). The adsorption process, mainly chemical adsorption, conforms to the Lagergren second-order kinetic equation (R2 = 0.9952 and 0.9932). The adsorption isotherms have a higher fitting degree with the Langmuir model (R2 = 0.9964 and 0.9966), and the adsorption is a monolayer adsorption process. This study can provide a reference for treating heavy metals in acid mine drainage and resource utilization of fly ash.

4.
Proteomics ; : e2300359, 2024 Mar 24.
Article En | MEDLINE | ID: mdl-38522029

Risk prediction and disease prevention are the innovative care challenges of the 21st century. Apart from freeing the individual from the pain of disease, it will lead to low medical costs for society. Until very recently, risk assessments have ushered in a new era with the emergence of omics technologies, including genomics, transcriptomics, epigenomics, proteomics, and so on, which potentially advance the ability of biomarkers to aid prediction models. While risk prediction has achieved great success, there are still some challenges and limitations. We reviewed the general process of omics-based disease risk model construction and the applications in four typical diseases. Meanwhile, we highlighted the problems in current studies and explored the potential opportunities and challenges for future clinical practice.

5.
Proteomics ; 24(6): e2300235, 2024 Mar.
Article En | MEDLINE | ID: mdl-38197532

Changes in the structure of RNA and protein, have an important impact on biological functions and are even important determinants of disease pathogenesis and treatment. Some genetic variations, including copy number variation, single nucleotide variation, and so on, can lead to changes in biological function and increased susceptibility to certain diseases by changing the structure of RNA or protein. With the development of structural biology and sequencing technology, a large amount of RNA and protein structure data and genetic variation data resources has emerged to be used to explain biological processes. Here, we reviewed the effects of genetic variation on the structure of RNAs and proteins, and investigated their impact on several diseases. An online resource (http://www.onethird-lab.com/gems/) to support convenient retrieval of common tools is also built. Finally, the challenges and future development of the effects of genetic variation on RNA and protein were discussed.


DNA Copy Number Variations , RNA , RNA/genetics , Proteins/chemistry
6.
Neurosci Lett ; 817: 137513, 2023 11 20.
Article En | MEDLINE | ID: mdl-37827449

N6-methyladenosine (m6A) is one of the most abundant chemical modifications on RNA and can affect the occurrence and development of diseases. Some studies have shown that the expressions of some m6A-related genes are significantly regulated by single nucleotide variants (SNV). However, the function of m6A-associated single nucleotide polymorphisms (m6A-SNP) remains unclear in multiple sclerosis (MS), Alzheimer's disease (AD) and Parkinson's disease (PD). Here, we identified the disease-associated m6A-SNPs by integrating genome-wide association study (GWAS) and m6A-SNPs from the RMVar database, and confirmed the relationship between these identified m6A-SNPs and their target genes in eQTL analysis and gene differential expression analysis. Finally, 26 genes corresponding to 20 m6A-SNPs with eQTL signals were identified and differentially expressed (P < 0.05) in MS, 15 genes corresponding to 12 m6A-SNPs (P < 1e-04) were differentially expressed in AD, and 27 PD-associated m6A-SNPs that regulated the expression of 31 genes were identified. There were 5 HLA genes with eQTL signals (HLA-DQB1, HLA-DRB1, HLA-DQA1, HLA-DQA2 and HLA-DQB1-AS1) to be detected in the three diseases. In summary, our study provided new insights into understanding the potential roles of these m6A-SNPs in disease pathogenesis as well as therapeutic target.


Alzheimer Disease , Multiple Sclerosis , Parkinson Disease , Humans , Genome-Wide Association Study , Genetic Predisposition to Disease , Polymorphism, Single Nucleotide , Multiple Sclerosis/pathology , Alzheimer Disease/genetics , Parkinson Disease/genetics
7.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 35(3): 269-273, 2023 Mar.
Article Zh | MEDLINE | ID: mdl-36916339

OBJECTIVE: To analyze the application effect of health failure mode and effect analysis (HFMEA) model in patients with artificial airways in the cardiovascular surgery intensive care unit (CSICU) by establishing a HFMEA project team, and to develop targeted improvement measures and processes. METHODS: The patients undergoing cardiovascular surgeries and with established artificial airways in the Shandong Provincial Hospital Affiliated to Shandong First Medical University were recruited from October 2021 to March 2022. The enrolled patients were divided into the conventional management group and the HFMEA model management group according to random number table method. The conventional management group applied the conventional procedures for monitoring the air bag pressure. The HFMEA model management group used the HFMEA model to implement and improve the airbag pressure monitoring process. The efficacy of HFMEA was assessed by comparing the incidence of ventilator-associated pneumonia (VAP), the pass rate of airbag pressure monitoring, the duration of endotracheal intubation and the length of CSICU stay between two groups. The practicability of HFMEA model was evaluated by analyzing the theoretical assessment scores and practical skill scores of nurses and their satisfaction scores with HFMEA. RESULTS: Compared with the conventional management group, the patients in the HFMEA mode management group had a significantly higher rate of passing airbag pressure monitoring [94.99% (2 994/3 152) vs. 69.97% (1 626/2 324), P < 0.01], shorter duration of endotracheal intubation and length of CSICU stay [duration of endotracheal intubation (hours): 6 (7, 12) vs. 6 (8, 13), length of CSICU stay (hours): 40 (45, 65) vs. 41 (46, 85), both P < 0.05], but the incidences of VAP between the two groups were similar. The theoretical assessment scores and practical skill scores of nurses were significantly higher (theoretical assessment score: 44.47±2.72 vs. 37.59±6.56, practical skill score: 44.56±2.66 vs. 40.03±4.32, total score: 89.03±3.07 vs. 77.63±9.56, all P < 0.05) in the HFMEA mode management group. And the satisfaction scores with airbag pressure management were also significantly higher in the HFMEA mode management group (7.72±1.11 vs. 6.44±1.32, P < 0.05). CONCLUSIONS: The application of the HFMEA can improve the airbag pressure measures and standardize the monitoring procedures in patients with artificial airways, and reduce the risk of clinical nursing. It is safe and effective for patients with invasive mechanical ventilation in the CSICU.


Air Bags , Healthcare Failure Mode and Effect Analysis , Pneumonia, Ventilator-Associated , Humans , Respiration, Artificial/methods , Intensive Care Units
8.
ACS Omega ; 8(4): 4046-4059, 2023 Jan 31.
Article En | MEDLINE | ID: mdl-36743035

Sulfate reducing bacteria (SRB) can simultaneously and efficiently remove SO4 2- and heavy metal ions from acid mine drainage (AMD). Environmental factors have a great influence on AMD treated by SRB metabolic reducing sulfate. Providing a suitable growth environment can improve the effect of SRB on AMD. In this paper, the wet soil around the tailings reservoir was used as seed mud to enrich SRB. Based on the single factor experiment method and the response surface methodology (RSM), the effects of temperature, environmental pH value, S2- concentration, and COD/SO4 2- on the growth of SRB were analyzed. The effects of environmental factors such as temperature and pH on the desulfurization performance of SRB were investigated. The results showed that the growth curve of SRB was "S" type. SRB was in the logarithmic phase when cultured for 14-86 h, with high activity and vigorous growth metabolism. When the temperature is 32∼35 °C, the activity of SRB is the highest. With the gradual increase of the S2- concentration in the culture system, SRB activity will be inhibited and even lead to SRB cell death. The environmental pH value that SRB can tolerate is 5∼8, and when the environmental pH value is 7∼8, the SRB activity is the strongest. The chemical oxygen demand (COD)/SO4 2- that is most suitable for SRB growth is 2. The optimal growth conditions of SRB obtained from RSM were as follows: culture temperature at 34.74 °C, initial pH being 8.00, and initial COD/SO4 2- being 1.98. Under these conditions, the OD600 value was 1.45, the pH value was 9.37, the oxidation reduction potential (ORP) value was -399 mV, and the removal percentage of SO4 2- was 88.74%. The results of RSM showed that the effects of culture temperature, environmental pH, and COD/SO4 2- on the desulfurization performance of SRB were extremely significant. The order of affecting the removal of SO4 2- by SRB was environmental pH > temperature > COD/SO4 2-.

9.
Nucleic Acids Res ; 51(D1): D1381-D1387, 2023 01 06.
Article En | MEDLINE | ID: mdl-36243962

Advances in sequencing technologies have led to the rapid growth of multi-omics data on rheumatoid arthritis (RA). However, a comprehensive database that systematically collects and classifies the scattered data is still lacking. Here, we developed the Rheumatoid Arthritis Bioinformatics Center (RABC, http://www.onethird-lab.com/RABC/), the first multi-omics data resource platform (data hub) for RA. There are four categories of data in RABC: (i) 175 multi-omics sample sets covering transcriptome, epigenome, genome, and proteome; (ii) 175 209 differentially expressed genes (DEGs), 105 differentially expressed microRNAs (DEMs), 18 464 differentially DNA methylated (DNAm) genes, 1 764 KEGG pathways, 30 488 GO terms, 74 334 SNPs, 242 779 eQTLs, 105 m6A-SNPs and 18 491 669 meta-mQTLs; (iii) prior knowledge on seven types of RA molecular markers from nine public and credible databases; (iv) 127 073 literature information from PubMed (from 1972 to March 2022). RABC provides a user-friendly interface for browsing, searching and downloading these data. In addition, a visualization module also supports users to generate graphs of analysis results by inputting personalized parameters. We believe that RABC will become a valuable resource and make a significant contribution to the study of RA.


Arthritis, Rheumatoid , Databases, Factual , Humans , Arthritis, Rheumatoid/genetics , Biomarkers/metabolism , Computational Biology/methods , DNA Methylation/genetics , Gene Expression Profiling/methods , Transcriptome
10.
Environ Sci Pollut Res Int ; 30(2): 3351-3366, 2023 Jan.
Article En | MEDLINE | ID: mdl-35947258

In this study, lignite-loaded nano-FeS (nFeS@Lignite) was successfully prepared by ultrasonic precipitation, and its potential for treating acid Cr(VI)-containing wastewater was explored. The results showed that the 40--80-nm rod-shaped nFeS was successfully loaded onto lignite particles, and the maximum adsorption capacity of Cr(VI) by nFeS@Lignite reached 33.08 mg∙g-1 (reaction time = 120 min, pH = 4, temperature = 298.15 K). The adsorption process of Cr(VI) by nFeS@Lignite fitted the pseudo-second-order model and the Langmuir isotherm model, and thermodynamic results showed that the adsorption process was an endothermic process with an adsorption enthalpy of 28.0958 kJ·mol-1. The inhibition intensity of coexisting anions on Cr(VI) removal was in the order of PO43- > NO3- > SO42- > Cl-, and the increase of ionic strength resulted in more pronounced inhibition. Electrostatic adsorption, reduction, and precipitation were synergistically engaged in the adsorption of Cr(VI) by nFeS@Lignite, among which reduction played a major role. The characterization results showed that Fe2+, S2-, and Cr(VI) were converted to FeOOH, S8, SO42-, Fe2O3, Cr2O3, and Fe(III)-Cr(III) complexes. This research demonstrates that nFeS@Lignite is a good adsorbent with promising potential for application in the remediation of heavy metal-contaminated wastewater.


Wastewater , Water Pollutants, Chemical , Ferric Compounds/chemistry , Water Pollutants, Chemical/analysis , Chromium/chemistry , Adsorption , Kinetics
11.
J Funct Biomater ; 13(4)2022 Oct 09.
Article En | MEDLINE | ID: mdl-36278651

BACKGROUND AND OBJECTIVE: Ventricular septal defects (VSDs) are the most common form of congenital heart defects. The incidence of VSD accounts for 40% of all congenital heart defects (CHDs). With the development of interventional therapy technology, transcatheter VSD closure was introduced as an alternative to open heart surgery. Clinical trials of VSD occluders have yielded promising results, and with the development of new material technologies, biodegradable materials have been introduced into the application of occluders. At present, the research on the mechanical properties of occluders is focused on experimental and clinical trials, and numerical simulation is still a considerable challenge due to the braided nature of the VSD occluder. Finite element analysis (FEA) has proven to be a valid and efficient method to virtually investigate and optimize the mechanical behavior of minimally invasive devices. The objective of this study is to explore the axial resistive performance through experimental and computational testing, and to present the systematic evaluation of the effect of various material and braid parameters by FEA. METHODS: In this study, an experimental test was used to investigate the axial resistive force (ARF) of VSD Nitinol occluders under axial displacement loading (ADL), then the corresponding numerical simulation was developed and compared with the experimental results to verify the effectiveness. Based on the above validation, numerical simulations of VSD occluders with different materials (polydioxanone (PDO) and Nitinol with different austenite moduli) and braid parameters (wire density, wire diameter, and angle between left and right discs) provided a clear presentation of mechanical behaviors that included the maximal axial resistive force (MARF), maximal axial displacement (MAD) and initial axial stiffness (IAS), the stress distribution and the maximum principal strain distribution of the device under ADL. RESULTS: The results showed that: (1) In the experimental testing, the axial resistive force (ARF) of the tested occluder, caused by axial displacement loading (ADL), was recorded and it increased linearly from 0 to 4.91 N before reducing. Subsequent computational testing showed that a similar performance in the ARF was experienced, albeit that the peak value of ARF was smaller. (2) The investigated design parameters of wire density, wire diameter and the angle between the left and right discs demonstrated an effective improvement (7.59%, 9.48%, 1.28%, respectively, for MARF, and 1.28%, 1.80%, 3.07%, respectively, for IAS) for the mechanical performance for Nitinol occluders. (3) The most influencing factor was the material; the performance rose by 30% as the Nitinol austenite modulus (EA) increased by 10,000 MPa. The performance of Nitinol was better than that of PDO for certain wire diameters, and the performance improved more obviously (1.80% for Nitinol and 0.64% for PDO in IAS, 9.48% for Nitinol and 2.00% for PDO in MARF) with the increase in wire diameter. (4) For all of the models, the maximum stresses under ADL were distributed at the edge of the disc on the loaded side of the occluders. CONCLUSIONS: The experimental testing presented in the study showed that the mechanical performance of the Nitinol occluder and the MARF prove that it has sufficient ability to resist falling out from its intended placement. This study also represents the first experimentally validated computational model of braided occluders, and provides a perception of the influence of geometrical and material parameters in these systems. The results could further provide meaningful suggestions for the design of biodegradable VSD closure devices and to realize a series of applications for biodegradable materials in VSD.

12.
ACS Omega ; 7(36): 32331-32338, 2022 Sep 13.
Article En | MEDLINE | ID: mdl-36119996

Chromium has been considered as one of the most hazardous heavy metals because of its strong and persistent toxicity to the ecosystem and human beings. In this study, fly ash-loaded nano-FeS (nFeS-F) composites were constructed with fly ash as the carrier, and the performance and mechanism of the composites for the removal of Cr(VI) and total chromium from water were investigated. The composite was characterized by X-ray diffraction and transmission electron microscopy. The effects of fly ash size, molarity of FeSO4, and flow rate of FeSO4 solution on the removal of Cr(VI) and total chromium were investigated by a single factor experiment. The interaction of various factors was studied by the Box-Behnken response surface methodology. The optimum conditions of removal of Cr(VI)and total chromium by nFeS-F were determined. The results show that ① the optimal preparation conditions for nFeS-F were an FeSO4 concentration of 0.45 mol/L, a fly ash particle size of 120-150 mesh, and a flow rate of 0.43 mL/s.② The response surface model provides reliable predictions for the removal efficiencies of Cr(VI) and total chromium.③ The removal efficiencies of Cr(VI) and total chromium were 92.87 and 83.53%, respectively, under the optimal preparation conditions by the experimental test. This study provides an effective method for the removal of Cr(VI) and total chromium.

13.
Heart Lung ; 56: 24-28, 2022.
Article En | MEDLINE | ID: mdl-35649307

BACKGROUND: Hypoxemic respiratory failure is a serious complication that can occur at any stage after cardiac surgery. Prone positioning (PP) is safe and effective for patients receiving invasive ventilation after hypoxemic respiratory failure; however, few related studies have focused on its use with extubated cardiac surgery patients. Researchers recently reported beneficial effects of PP for hypoxemic patients with COVID-19 and those with moderate ARDS (acute respiratory distress syndrome,ARDS). PP may also improve oxygenation in extubated cardiac surgery patients. OBJECTIVE: In this study, we aimed to assess the safety and effectiveness of PP in extubated cardiac surgery patients to determine whether PP can improve oxygenation and respiratory status or reduce secondary intubation. METHODS: We reviewed our institutional database between August 2018 and August 2020 and identified 22 cardiac surgery patients who had undergone PP for hypoxemic respiratory failure after extubation. From the medical and nursing records, we extracted the following data recorded before PP, during PP, and after PP for each patient, arterial blood gas analyses, hemodynamic records, laboratory reports, and respiratory function training records. RESULTS: Twenty-two extubated patients underwent 74 PP. Each patient underwent a median of 3.5 (2-5) procedures, and the median duration of each PP was 10 h. PP was implemented on the 4.5th postoperative day (median). All patients were discharged from the hospital, and none died. No complications were observed. PP improved the P/F ratio (182.65 ± 60.17, 301.53 ± 61.31, and 246.76 ± 65.68, before PP, during PP, and after PP, respectively, p < 0.001). Additionally, the respiratory rate, Forced Vital Capacity (FVC) and PaCO2 also improved, and hemodynamics showed no significant change. CONCLUSION: PP may be effective and safe for treating patients who are extubated following cardiac surgery with hypoxemic respiratory failure. For these patients, PP is associated with oxygenation and respiratory condition improvements and low secondary intubation rates.


COVID-19 , Cardiac Surgical Procedures , Respiratory Distress Syndrome , Respiratory Insufficiency , Humans , Prone Position , Retrospective Studies , Airway Extubation , COVID-19/complications , Respiratory Insufficiency/etiology , Respiratory Insufficiency/therapy , Respiratory Distress Syndrome/etiology , Respiratory Distress Syndrome/therapy , Cardiac Surgical Procedures/adverse effects
14.
RSC Adv ; 12(10): 6054-6062, 2022 Feb 16.
Article En | MEDLINE | ID: mdl-35424544

In terms of the problem of severe pollution to the ecological environment caused by the acidic chrome-containing wastewater produced in the tanning, electroplating, metallurgy, printing and dyeing and other industries, based on the good adsorbability, reducibility and other properties of heavy metals such as Cr(vi) by lignite and nano FeS, the lignite-loaded nano FeS adsorbing material (nFeS-lignite) was prepared by ultrasonic precipitation method. NFeS-lignite and lignite were used as fillers to construct 1# and 2# dynamic columns to carry out the dynamic treatment experiment of acidic chrome-containing wastewater. And nFeS-lignite and lignite were characterized by XRD, SEM and EDS to explore the regularity, long-acting properties and removal mechanism of acidic chrome-containing wastewater treated by NFeS-lignite and lignite. The results indicate that: ① during 25 days of operation, the average removal percentages of Cr(vi) in the 1# and 2# dynamic columns are 71.6% and 53.1%. The average removal percentages of total chromium in 1# and 2# dynamic columns are 54.4% and 28.8%, and the average effluent pH of 1# and 2# dynamic columns is 5.3 and 7.3. ② According to XRD, SEM, EDS and FTIR analysis, the reducing groups in the structure of nFeS-lignite, such as -CH3, -CH2, C-O and Ar-OH, participate in the reaction and are oxidized to C[double bond, length as m-dash]C, C[double bond, length as m-dash]O and other groups. A large number of sediment crystals appeared on the particle surface, and new diffraction peaks such as FeOOH, Cr(OH)3 and Cr2S3 appeared at the same time, indicating that after Cr(vi) was reduced to Cr(iii), it would be fixed on the surface of nFeS-lignite in the form of precipitation such as hydroxide and sulfide.

15.
RSC Adv ; 12(8): 4595-4604, 2022 Feb 03.
Article En | MEDLINE | ID: mdl-35425486

The problems of acid mine drainage (AMD) in coal mine acidic wastewaters arise from a range of sources, including severe pollution with heavy metals and SO4 2- and difficulties during treatment. Based on the ability of Maifan stone to adsorb heavy metals and the dissimilatory reduction of SO4 2- by sulfate-reducing bacteria (SRB), Maifan stone-sulfate-reducing bacterium-immobilized particles were prepared via immobilization techniques using Shandong Maifan stone as the experimental material. A single factor experiment was used to investigate the influences of the dosage of Maifan stone, the particle size of Maifan stone and the dosage of SRB on the pH improvement effect and the removal rates of SO4 2-, Fe2+ and Mn2+. The Box-Behnken response surface method was used to determine the optimal preparation conditions for the Maifan stone and SRB immobilized particles in accordance with the ion removal rate and pH improvement effect when dealing with AMD. The results show that: (1) the optimal preparation conditions for Maifan stone synergistic SRB immobilized particles are determined by single factor experiment: the dosage of Maifan stone is 5 g, the particle size of Maifan stone is 0.075-0.106 mm, and the dosage of SRB is 25 mL per 100 mL; the removal rates of SO4 2-, Fe2+ and Mn2+ from AMD by the Maifan stone and SRB immobilized particles prepared under these conditions were 92.22%, 95.41% and 86.05%, and the pH was increased from 4.08 to 7.45. (2) From the variance analysis of the response surface model, it can be seen that the model effectively predicts the SO4 2- removal rate, Fe2+ removal rate, Mn2+ removal rate and pH change. (3) After further optimization using the response surface method, the optimal preparation conditions of Maifan stone and SRB immobilized particles are determined as follows: Maifan stone dosage is 5 g, Maifan stone particle size is 0.075-0.106 mm, and SRB dosage is 25 mL per 100 mL. Through experiments, the removal rates of SO4 2-, Fe2+ and Mn2+ from AMD by the Maifan stone and SRB immobilized particles prepared under these conditions were 92.12%, 95.93% and 87.14%, respectively, and the pH was increased from 4.08 to 7.49.

16.
PLoS One ; 17(1): e0261823, 2022.
Article En | MEDLINE | ID: mdl-35045075

The problems of acid mine drainage (AMD) in coal mine acidic wastewaters arise from a range of sources, including severe pollution with heavy metals and SO42- and difficulties during treatment. Based on the ability of Maifan stone to adsorb heavy metals and the dissimilatory reduction of SO42- by sulfate-reducing bacteria (SRB), Maifan stone-sulfate-reducing bacterium-immobilized particles were prepared via immobilization techniques using Shandong Maifan stone as the experimental material. The effects of Maifan stones containing SRB on mitigating AMD were investigated by constructing Dynamic Column 1 with Maifan stone-sulfate-reducing bacterium-immobilized particles and by constructing Dynamic Column 2 with SRB mixed with Maifan stones. By the use of adsorption isotherms, adsorption kinetics, a reduction kinetics model and X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies, the mechanism by which Maifan stone-sulfate-reducing bacterium-immobilized particles mitigate AMD was revealed. The results showed that the total effect of Maifan stone-sulfate-reducing bacterium-immobilized particles on AMD was better than that of biological Maifan stone carriers. The highest rates for the removal of Fe2+, Mn2+, and SO42- in AMD were 90.51%, 85.75% and 93.61%, respectively, and the pH value of the wastewater increased from 4.08 to 7.64. The isotherms for the adsorption of Fe2+ and Mn2+ on Maifan stone-sulfate-reducing bacterium-immobilized particles conformed to the output of the Langmuir model. The adsorption kinetics were in accordance with Lagergren first-order kinetics, and the kinetics for the reduction of SO42- conformed to those of a first-order reaction model.


Bacteria/growth & development , Iron/metabolism , Manganese/metabolism , Mining , Sulfates/metabolism , Wastewater/microbiology , Biodegradation, Environmental , Water Purification
17.
PeerJ ; 8: e8478, 2020.
Article En | MEDLINE | ID: mdl-32025383

Sensitive seedling crops have been developed to monitor Cadmium (Cd) contamination in agricultural soil. In the present study, 18 parameters involving growth conditions and physiological performances were assessed to evaluate Cd-responses of three wheat (Triticum aestivum L.) cultivars, Xihan1 (XH), Longzhong1 (LZ) and Dingfeng16 (DF). Principle component analysis illustrated that Factor 1, representing growth performance, soluble sugar content and catalase activity, responded to the Cd treatments in a dose dependent manner, while Factor 2 represented by chlorophyll content and germinating root growth was mainly dependent on cultivar differences. Higher inhibition rates were observed in growth performance than in physiological responses, with the highest inhibition rates of shoot biomasses (39.6%), root length (58.7%), root tip number (57.8%) and bifurcation number (83.2%), even under the lowest Cd treatment (2.5 mg·L-1). According to the Cd toxicity sensitivity evaluation, DF exerted highest tolerance to Cd stress in root growth while LZ was more sensitive to Cd stress, suggesting LZ as an ideal Cd contaminant biomarker. This study will provide novel insight into the cultivar-dependent response during using wheat seedlings as Cd biomarkers.

18.
J Mech Behav Biomed Mater ; 28: 332-9, 2013 Dec.
Article En | MEDLINE | ID: mdl-24036280

The microstructure and mechanical properties of as-extruded Mg-8Y-1Er-2Zn (wt%) alloy containing long period stacking ordered (LPSO) phase are comparatively investigated before and after corrosion in a simulated body fluid (SBF) at 37°C. The as-extruded alloy consists of a long strip-like 18R-LPSO phase and some fine lamellae grains formed by primary recrystallization during the extrusion process. The hydrogen evolution volume per day fluctuates between 0.21 and 0.32ml/cm(2) in the immersion test for 240h, and the corresponding corrosion rate is calculated as 0.568mm/y. The corrosion product is determined as Mg(OH)2, whilst a Ca(H2PO4)2 compound is also observed on the surface of the samples. The corrosion site preferentially occurs at the interface between LPSO phase and Mg matrix. Before immersing, the tensile yield strength (TYS), ultimate tensile strength (UTS) and elongation of the alloy are 275MPa, 359MPa, and 19%, respectively. More attractively, these mechanical properties can be maintained even after immersing in SBF for 240h (TYS, UTS and elongation are 216MPa, 286MPa and 6.8%, respectively) because of the existence of high anti-corrosion LPSO phase.


Alloys/chemistry , Alloys/metabolism , Biocompatible Materials/chemistry , Biocompatible Materials/metabolism , Materials Testing , Mechanical Phenomena , Body Fluids/metabolism , Corrosion , Erbium/chemistry , Immersion , Magnesium/chemistry , Yttrium/chemistry , Zinc/chemistry
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