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1.
Food Chem ; 368: 130841, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34425335

RESUMO

This study aimed to optimize an ion-exchange chromatography method for an accurate quantification of phosphates. Coelution of nucleotides was detected following the quantification of small amounts of di- and trimetaphosphates in hake fillets. In some samples, triphosphates were added to the glaze ice, therefore, defrosting waters (glaze ice + drip loss of fillets) should be analyzed for an effective assessment of the use of phosphates in seafood. Even low amounts of adenosine 5'-diphosphate (ADP) and inosine 5'-monophosphate (IMP) triggered false positive results for P2O74- and P3O93-. Keeping the initial isocratic conditions for longer was crucial for the separation of ADP from P2O74- and of IMP from P3O93-. The improved method showed that in general, hake fillets did not have diphosphates, and trimetaphosphates were residual. Triphosphates were clearly added in only four defrosting waters, and in most of the remaining ones, diphosphates and trimetaphosphates contents corresponded to false positive results.


Assuntos
Gadiformes , Fosfatos , Nucleotídeos de Adenina , Difosfato de Adenosina , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Difosfatos
2.
J Appl Oral Sci ; 29: e20210081, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34614120

RESUMO

OBJECTIVE: To evaluate the effect of a toothpaste containing calcium silicate/sodium phosphate/fluoride associated or not to the boost serum (BS) against erosive tooth wear (ETW) on enamel and dentin. METHODOLOGY: Bovine enamel and dentin specimens were subjected to an erosion-abrasion cycling model (1% citric acid - pH 3.6 -2 min / artificial saliva - 60 min, 4×/day, 5 days). Toothbrushing was performed for 15 s (2 min exposed to slurry), 2×/day, with the toothpastes (n=10): control without fluoride (Weleda), Arg/Ca/MFP (Colgate Pro-Relief), Si/PO4/MFP (Regenerate-Unilever), and Si/PO4/MFP/BS (Si/PO4/MFP with dual BS - Advanced Enamel Serum-Unilever). The effect of treatments on the eroded tissues was assessed by surface microhardness in the first day, and surface loss (SL) resulting from ETW was evaluated by profilometry (µm) after three and five days. Additional dentin specimens (n=5/group) were subjected to 20,000 brushing cycles to verify the abrasivity of the toothpastes. Data were subjected to ANOVA and correlation tests (5%). RESULTS: For enamel, no difference in microhardness was observed among the treated groups, and similar SL was obtained after 5 days. For dentin, Si/PO4/MFP/BS resulted in higher microhardness values, but none of the groups presented significantly lower SL than the control. There was no significant correlation between SL and abrasiveness. CONCLUSION: The calcium silicate/sodium phosphate toothpaste and serum increased microhardness of eroded dentin, but they did not significantly reduce enamel and dentin loss compared to the non-fluoride control toothpaste. The abrasiveness of the toothpastes could not predict their effect on ETW.


Assuntos
Fluoretos , Cremes Dentais , Animais , Compostos de Cálcio , Bovinos , Esmalte Dentário , Dentina , Fosfatos , Silicatos
3.
Mymensingh Med J ; 30(4): 1031-1042, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34605474

RESUMO

The chronic kidney disease (CKD) is associated with a variety of bone disorders and disorders of calcium and phosphorus metabolism. Bone disease associated with chronic kidney disease having higher rate of CKD progression and increased risk of death. To see the status of serum calcium, phosphate and intact parathyroid hormone in pre-dialysis CKD (stage- 3 to 5) patients. This was a across sectional study done in outpatient department of Nephrology of National Institute of Kidney Diseases and Urology, Dhaka, between 1st June 2012 to 31st May 2013. The patients of CKD stage 3, 4 and 5 yet not on dialysis attending out patients department of Nephrology, NIKDU by using MDRD-4 equation according to K/DOQI guidelines and reviewing previous medical records and investigation reports were enrolled in this study. There after serum calcium (corrected for serum albumin), phosphate and iPTH levels were measured and compared with the recommended target ranges in K/DOQI guideline. The number of patients with serum levels according to K/DOQI guidelines for different stages CKD(3,4,5) were as follows: serum calcium: 56.6, 58.5 and 76.7; serum phosphate: 55.2, 58.5 and 56.7; iPTH 37.9, 12.2 and 36.7 and Ca x P product 100.0, 97.6 and 86.7, respectively. The percentages of patients (who received drug) with serum calcium levels within according to K/DOQI guidelines for stages 3, 4 and 5 were as follows: serum calcium: 63.2%, 64.7% and 83.3%; respectively, serum phosphate: 63.2%, 61.8% and 66.7%; respectively, iPTH 42.1%, 14.7% and 4.7% and Ca x P product 100.0%, 100.0% and 87.5%, respectively. On the other hand patients who didn't receive drug the percentages of patients with serum calcium levels according to K/DOQI guidelines for CKD stages 3, 4 and 5 were as follows: serum calcium: 50.0%, 28.6% and 50.0%; respectively, serum phosphate: 40.0%, 42.9% and 16.7%; respectively, iPTH 30.0%, 14.7% and 16.7% and Ca x P product 100.0%, 85.7% and 83.3%, respectively. The patients achieving the four recommendations of K/DOQI guidelines was 4(13.8%) in stage-3, 3(7.3%) in stage-4 and 5(16.7%) in stage-5. More than half of the pre-dialysis patients of CKD were within target range of serum calcium and phosphate recommended in K/DOQI guideline and this proportion was more in those who were taking both phosphate binder and Vit-D. Ca x P was within target range in almost all patients so it may not be an important parameter for therapeutic decision making. However majority of the patients were out of target range of iPTH even though having normal serum calcium and phosphate level. So emphasis should be given in monitoring of iPTH level in early stages of CKD.


Assuntos
Cálcio , Insuficiência Renal Crônica , Bangladesh , Humanos , Hormônio Paratireóideo , Fosfatos , Diálise Renal , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/terapia
4.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 39(5): 531-539, 2021 Oct 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34636200

RESUMO

OBJECTIVES: This study was performed to fabricate a bionic coating with titanium (Ti) phosphate to promote the osseointegration of Ti substrate implants. METHODS: Phosphorylated micro/nanocoating was prepared on the surface of pure titanium (i.e., TiP-Ti) by hydrothermal process under special pressure, and the untreated smooth pure titanium (cp-Ti) was selected as the control. To evaluate the characteristics of the coating surface, scanning electron microscopy, X-ray diffraction, atomic force microscopy, and contact-angle measurement were performed. In addition, the effects of TiP-Ti on the proliferation, adhesion, and differentiation of rat bone marrow mesenchymal stem cells (BMSCs) were investigated by using in vitro cytology. Finally, TiP-Ti implants were implanted into the rat tibia, and the effect of TiP-Ti on the osseointegration in the host was evaluated after 12 weeks. RESULTS: The TiP-Ti surface presented a bionic structure with coexisting nanoscale 3D spatial structure and microscale pores. In vitro experiments showed that the BMSCs had enhanced adhesion, proliferation, and osteogenic differentiation on the TiP-Ti surface. Furthermore, in vivo, TiP-Ti showed considerably stronger osseointegration compared with pure titanium, and the ultimate shear strength and maximum pushing force were significantly improved. CONCLUSIONS: A bionic structure with TiP-Ti micro/nanoscale coating was successfully fabricated, indicating a promising method for modifying the surface of implants.


Assuntos
Implantes Dentários , Osseointegração , Animais , Osteogênese , Óxidos , Fosfatos , Ratos , Propriedades de Superfície , Titânio
5.
Ying Yong Sheng Tai Xue Bao ; 32(9): 3097-3106, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34658194

RESUMO

To investigate the interaction between Pinus tabuliformis and root microorganisms and its effects on the stability of P. tabuliformis forests, we collected rhizosphere and non-rhizosphere soil from natural and planted P. tabuliformis forests in Huanglong County of Shaanxi Province. The non-rhizosphere soil was used to analyze chemical properties, while the rhizosphere soil was used to isolate and purify phosphorus-solubilizing (organic and inorganic phosphorus) bacteria. We mea-sured the phosphate-solubilizing ability and identified those bacteria using DNA genes sequencing. The results showed that soil total carbon concentration (TC), total nitrogen concentration (TN), carbon:nitrogen (C/N), and nitrogen:phosphorus (N/P) were significantly higher in natural forest than those in the plantation. A total of 20 genera and 65 species of phosphate-solubilizing bacteria were identified in those two forests, with Bacillus, Streptomyces and Pseudomonas as the dominant group. The diversity, richness, and evenness of phosphate-solubilizing bacteria in the natural forest were higher than that in the planted forest, but dominance was lower. Streptomyces was positively correlated with soil TC, TN, C/N and N/P ratios, while Bacillus and Pseudomonas were positively correlated with soil nitrate (NO3-), ammonium (NH4+), available phosphorus (AP), and total phosphorus (TP). The solubilizing ability of phosphate-solubilizing bacteria was different between two forest types, indicating that Pseudomonas sp.34-5 shared in two forests had the strongest phosphate-solubilizing ability for calcium phosphate with 11.40 µg·mL-1 and Bacillus mycoides BF1-5 exclusive to natural forest had the strongest phosphate-solubilizing ability for lecithin with 4.58 µg·mL-1. The composition and structure of phosphorus-solubilizing bacterial community were different in two forest types, with higher diversity, richness and phosphate-solubilizing ability in natural forest than that in plantation.


Assuntos
Pinus , Rizosfera , Bacillus , Bactérias/genética , China , Florestas , Fosfatos , Solo , Microbiologia do Solo
6.
Enzyme Microb Technol ; 151: 109920, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34649691

RESUMO

Research on the ability and mechanism of genetically recombinant E. coli DH5α containing DSR A gene to enrich uranium under culture conditions provides a theoretical basis for the application of the bacteria in the treatment of uranium pollution. By exploring the influence of factors such as the initial concentration of uranium, culture time, and inoculation amount on the characteristics of uranium enrichment in genetically recombinant E. coli, using FTIR, SEM-EDS, XPS and XRD explore the mechanism of uranium-enriched bacteria. The results showed that when initial UO22+ concentration reach 600 mg/L, E. Coli D1 could not survived, indicated that the maximum tolerance concentration is lower than 600 mg/L. While concentration between 0∼500 mg/L, strains D1 can grow normally and has the ability to enrich uranium. In the prime stage, strains D1 resist toxics through release inorganic phosphates to precipitate UO22+ on cell wall, after 96 h, most UO22+ were transferred into cytoplasm and metabolized into U(IV) which is less toxic. In the metabolize process, all groups involved in metabolizing UO22+, especially protein contain groups like hydroxyl, amine and carboxyl paly a huge role. It shows that within a certain concentration rage, strains D1 has a good enrichment effect on uranium under culture conditions.


Assuntos
Escherichia coli , Urânio , Bactérias , Escherichia coli/genética , Fosfatos , Urânio/análise
7.
Nanoscale ; 13(30): 13057-13064, 2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34477789

RESUMO

We developed a water-soluble, stable and selective "turn-on" fluorescence sensing platform based on carbon quantum dots (CQDs) for rapid determination of phosphate (Pi) in aqueous solutions and for visualization of latent fingerprints on paper. The hydroxyl groups on the surface of the synthesized CQDs can be deprotonated by Pi to trigger the intramolecular charge transfer (ICT) process and the inhibition of excited-state proton transfer (ESPT), achieving a turn-on emission response. CQDs demonstrated the capability to selectively detect Pi over other common ions and biomolecules with the linear fluorescence intensity change in the range from 0 to 100 µM. Moreover, the paper sprayed with the CQD solution showed a remarkable blue emission speckle and a fingerprint upon addition of Pi solution and finger touching, respectively. Notably, the fingerprint images including level 3 details (crossover, bifurcation, termination, and island and sweat pores) are also clearly identified and distinguished, indicating their potential application in document security. We believe that the as-synthesized CQDs will provide a new tool for Pi detection in aqueous media and paper document security.


Assuntos
Pontos Quânticos , Carbono , Fluorescência , Íons , Fosfatos
8.
J Hazard Mater ; 416: 125758, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492777

RESUMO

In this study, we investigated chemical additives present in new and used spray polyurethane foams (SPFs) and assessed the dermal transfer through direct contact. This first study shows that cured do-it-yourself spray one-component SPFs (OCFs) often contain chlorinated paraffins (C14-C37), and tris (1-chloro-2-propyl) phosphate (TCIPP), ranging 0.2-50%, and 0.9-30% w/w, respectively. Six OCFs contained CP levels ranging 22-50% w/w, whereas nine OCFs used for similar applications only contained CP levels ranging 2-17% w/w. It is unclear if the combination CPs/TCIPP is meant to improve the flame retardancy of products, and could suggest an unnecessary use of high CPs/TCIPP concentrations in OCFs. The two-component SPFs (TCFs) contained only TCIPP with levels ranging from 7.0% to 9.0%. The CPs and TCIPP were easily transferred from cured OCFs to the hands. Levels up to 590 µg per hand for CPs and up to 2.7 µg per hand for TCIPP were found. After end-of-life, it is challenging to recycle used SPFs. They may, therefore, end up at landfills where the TCIPP/CPs may leach into the environment. Therefore, further investigation is needed to assess potential exposure risks associated with general and occupational use, and the impact of landfill leaching on the environment.


Assuntos
Retardadores de Chama , Poliuretanos , Parafina , Fosfatos
9.
J Hazard Mater ; 416: 125902, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492838

RESUMO

The high salt-bearing liquid radioactive waste (evaporator bottoms, EB) makes up the most voluminous NPP waste and needs solidification. In the paper presented, we introduce a novel formation process study of the struvite-based phosphate matrices ((K, NH4)MgPO4·6H2O) and the developed phosphate matrix compositions for the solidification of high salt-bearing solutions. The solutions simulate the EB of nuclear power plants with pressurized water reactors (NPP PWR). The effect of the EB's composition and salt content on the matrices' mechanical strength was investigated. The cesium-selective nickel-potassium ferrocyanide sorbent or 10-20% of MgO over the reaction stoichiometry, introduced at the matrix synthesis stage, allowed the production of matrices with the average 137Сs leach rate of less than 10-3 g cm-2 day-1 and the mechanical strength over 5 MPa. The matrices obtained completely satisfied the cemented radioactive waste requirements and contained up to 17-17.5 wt% of salts, which was 1.7-2.5 times higher compared to the Portland cement-based matrices.


Assuntos
Resíduos Radioativos , Materiais de Construção , Fosfatos , Cloreto de Sódio , Estruvita
10.
J Hazard Mater ; 416: 125916, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492849

RESUMO

Cadmium (Cd) pollution in paddy soil seriously endangers food safety production. To investigate the effects and microbiological mechanisms of calcium-magnesium-phosphate (CMP) fertilizer application on Cd reduction in rice, field experiments were conducted in Cd-contaminated paddy soil. Compared with conventional compound fertilizer, CMP fertilizer treatments inhibited Cd uptake through plant roots, significantly decreasing Cd content in rice grains from 0.340 to 0.062 mg/kg. Soil pH and total Ca, Mg and P contents increased after CMP fertilizer application, resulting in a further decrease in soil available Cd content from 0.246 to 0.181 mg/kg. Specific extraction analysis recorded a decrease in both available Fe content and the ratio of nitrate to ammonium nitrogen, indicating that the soil Fe-N cycle was affected by the addition of CMP fertilizer. This finding was also recorded using soil bacterial community sequencing, with CMP fertilizer promoting the progress of nitrate-dependent Fe-oxidation driven by Thiobacillus (1.60-2.83%) and subsequent dissimilatory nitrate reduction to ammonium (DNRA) driven by Ignavibacteriae (1.01-1.92%); Fe-reduction driven by Anaeromyxobacter (3.09-2.23%) was also inhibited. Our results indicate that CMP fertilizer application regulates the Fe-N coupling cycle driven by the soil microbial community to benefit remediation of Cd contaminated paddy soil.


Assuntos
Microbiota , Oryza , Poluentes do Solo , Cádmio/análise , Cádmio/toxicidade , Cálcio , Fertilizantes/análise , Ferro , Óxido de Magnésio , Nitrogênio , Fosfatos , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
11.
J Hazard Mater ; 416: 126240, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492991

RESUMO

Mineral dissolution and secondary phase precipitation may control the fate of inorganic contaminants introduced to soils and sediments during liquid waste discharges. When the solutions are aggressive enough to induce transformation of native minerals, incorporated contaminants may be released during dissolution due to percolation of meteoric waters. This study evaluated the release of uranium (U) from Hanford sediments that had been previously reacted for 180 or 365 days with liquid waste solutions containing U with and without 3 mM dissolved phosphate at pH 2 and 3. Flow-through column experiments were conducted under continuous saturated flow with a simulated background porewater (BPW; pH ~7) for 22 d. Up to 5% of the total U was released from the sediments reacted under PO4-free conditions, attributable to the dissolution of becquerelite and boltwoodite formed during weathering. Contrastingly, negligible U was released from PO4-reacted sediments, where meta-ankoleite was identified as the main U-mineral phase. Linear combination fits of U LIII-edge EXAFS spectra of sediments before and after BPW leaching and thermodynamic calculations suggest that the formed becquerelite and meta-ankoleite transformed into schoepite and a phosphuranylite-type phase, respectively. These results demonstrate the stabilization of U as recalcitrant uranyl minerals formed in sediments and highlight the key role of PO4 in U release at contaminated sites.


Assuntos
Urânio , Poluentes Radioativos da Água , Sedimentos Geológicos , Minerais , Fosfatos , Urânio/análise , Poluentes Radioativos da Água/análise
12.
BMJ Open ; 11(9): e044473, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34489265

RESUMO

OBJECTIVES: This research aims to explore the impact of serum phosphate on the mortality of critically ill patients. DESIGN: A retrospective large cohort study. SETTING: Our data were extracted from a publicly accessible database named 'Multiparameter Intelligent Monitoring in Intensive Care Database III'. PARTICIPANTS: 27 131 patients were included by clear definitions of selection and exclusion criteria. INTERVENTIONS: We used initial phosphate at admission as a design variable. Patients were divided into six groups with different serum phosphate levels and five groups at different intensive care unit (ICU) departments. PRIMARY AND SECONDARY OUTCOMES: 28-day and 90-day mortality were primary outcomes. All-cause mortality and length of stay ICU were secondary outcomes. RESULTS: Patients with very-high-normal serum phosphate, hypophosphataemia and hyperphosphataemia had worse outcomes. And the relationship between serum phosphate and the probability of 28-day or 90-day mortality had a linear relationship. After adjustment for potential confounders, hypophosphataemia and hyperphosphataemia were not significantly associated with 28-day or 90-day mortality. Nevertheless, at the medical ICU, hyperphosphataemia was associated with increased 28-day or 90-day mortality (HR=0.64, 95% CI 0.48 to 0.84, p=0.0017; HR=0.72, 95% CI 0.57 to 0.91, p=0.0067, respectively), using group 2 (≥2.5 mg/dL and <3.0 mg/dL) as the reference group. CONCLUSIONS: Patients with very-high-normal serum phosphate also had worse outcomes, it might be necessary to re-evaluate the definitions of the normal reference range for serum phosphate. Hypophosphataemia and hyperphosphataemia are not the independent risk factors of 28-day or 90-day ICU mortality, which leads us to consider whether phosphate monitoring is not a necessary measure in critically ill patients. But hyperphosphataemia was associated with increased 28-day or 90-day mortality at the medical ICU, which emphasises the potential importance of early diagnosis and treatment of hyperphosphataemia for the patients who were admitted to the medical ICU.


Assuntos
Estado Terminal , Unidades de Terapia Intensiva , Estudos de Coortes , Mortalidade Hospitalar , Humanos , Fosfatos , Estudos Retrospectivos
13.
J Biomed Nanotechnol ; 17(8): 1535-1544, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34544531

RESUMO

This study aimed to detect miR-455-5p and S1PR1 proteins using nanoparticle-assisted polymerase chain reaction (nano-PCR) to determine their correlation with cervical carcinoma prognosis. To achieve this study's goals, we selected 48 cervical carcinoma patients between January 2014 to January 2016 and subjected them to the miR-455-5p test by nano-PCR. The collected samples were then divided into two groups based on miR-455-5p levels. We had four HeLa cell groups, one group as the control, and one group overexpressed the miR-455-5p protein. A third group was miR-455-5p silent, and a separate group overexpressed both the miR-455-5p and S1PR1 proteins. Results also proved that the nano-PCR had a higher sensitivity than RT-PCR, and patients with poor prognosis had lesser miR-455-5p levels. Similarly, high levels of miR-455-5 contributed to cancer cell apoptosis and migration inhibition by targeting S1PR1 expression negatively. These two biomarkers are therefore significantly related to the prognosis of cervical carcinoma patients.


Assuntos
Carcinoma , Nanopartículas Metálicas , MicroRNAs , Neoplasias do Colo do Útero , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Ouro , Células HeLa , Humanos , Fosfatos , Reação em Cadeia da Polimerase , Esfingosina , Neoplasias do Colo do Útero/genética
14.
J Vet Intern Med ; 35(5): 2287-2295, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34469023

RESUMO

BACKGROUND: Medical dissolution of struvite uroliths in dogs is commonly recommended, but data on success rates and complications are limited. OBJECTIVES: To evaluate the efficacy of medical dissolution for suspected struvite cystoliths in dogs. ANIMALS: Fifty client-owned dogs fed a therapeutic dissolution diet, with or without administration of antimicrobials, for treatment of suspected struvite cystoliths. METHODS: Single institution, retrospective case series. Medical records were reviewed for dogs with at least 1 follow-up visit. Dissolution success, complications, and possible predictors of success were evaluated. RESULTS: Full dissolution of cystoliths was achieved in 58% (29/50) of dogs within a median of 35 days (range, 13-167). Of 21 dogs without success, 7 each had partial dissolution, no dissolution, or undetermined outcome. Uroliths containing >10% nonstruvite mineral were common in the nonsuccess group (11/16 analyzed). Maximum urolith diameter, number of uroliths, and baseline urine pH did not differ significantly between dogs with and without success. Dissolution was more likely in dogs receiving antimicrobial therapy (OR = 16.3, 95% confidence interval 1.9-787.4, P = .002). Adverse events occurred in 9 dogs (18%); urethral obstructions were the most common, but 3 of 4 dogs with this complication were obstructed on presentation, before trial initiation. CONCLUSIONS AND CLINICAL IMPORTANCE: Results support a medical dissolution trial for dogs with suspected struvite cystoliths. If no reduction in urolith size or number occurs by 1 month, a nonstruvite composition is likely, and alternative interventions should be considered. Dogs presenting with urethral obstructions should not be considered candidates for medical dissolution.


Assuntos
Doenças do Cão , Cálculos da Bexiga Urinária , Animais , Doenças do Cão/tratamento farmacológico , Cães , Compostos de Magnésio , Fosfatos , Estudos Retrospectivos , Solubilidade , Estruvita , Cálculos da Bexiga Urinária/veterinária
15.
Huan Jing Ke Xue ; 42(10): 4789-4797, 2021 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-34581121

RESUMO

Peroxymonosulfate(PMS)-based advanced oxidation processes were widely used for the degradation of organic pollutants. Electron-rich azo dye Acid Orange 7(AO7) was selected as the target organic matter in this work. The differences, influencing factors, efficiency, and mechanisms of a PMS/Co2+ homogeneous system in the degradation of organic pollutants with two different buffers of boric acid(Lewis acid) and phosphoric acid(Bronstede acid) were investigated. The k value of AO7 degradation in the PMS/Co2+ homogeneous system with phosphate buffer was greater than that with borate buffer, but the degradation percentage during the first 10 seconds of the reaction was lower in the former case. These differences were affected by buffer concentration, the PMS and Co2+ dosages, and pH. In the phosphate buffer, ·OH or SO4-· contributed to organic degradation in the PMS/Co2+ system, while in the borate buffer, the nonradical pathway(1O2) made a critical contribution to the removal of organics. This study provides a reference for the application of different types of buffers in the homogeneous catalysis of PMS.


Assuntos
Boratos , Poluentes Ambientais , Catálise , Oxirredução , Peróxidos , Fosfatos
16.
Huan Jing Ke Xue ; 42(10): 4815-4825, 2021 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-34581124

RESUMO

A cerium-modified water hyacinth biochar adsorbent(Ce-BC) was developed through co-precipitation-pyrolysis to remove phosphate from wastewater. The study investigated the effects of Ce-BC dosing, wastewater pH, reaction time, and coexisting competing ions on the adsorption process. The results showed that the best adsorption performance was achieved with a maximum adsorption capacity of 35.00 mg·g-1 at a Ce-BC dosage of 0.4 g·L-1 and an initial pH range of 3-10 in the phosphate solution. The adsorption process of phosphate by the Ce-BC followed the quasi-second-order kinetic model, and a phosphate removal efficiency of 98% within 1 h was achieved. In addition, Ce-BC had a strong anti-competitive anion interference and a good regeneration ability; after four cycles of regeneration, the adsorption efficiency remained above 90%. Characterization using field emission scanning electron microscopy-energy dispersive spectrometry(FESEM-EDS), Fourier-transform infrared spectroscopy(FTIR), X-ray diffraction(XRD), and X-ray photoelectron spectroscopy(XPS) showed that the adsorption mechanism of Ce-BC with respect to phosphate mainly involved ligand exchange and inner sphere complexation. The Ce-BC adsorbent prepared in this study effectively removed and recovered phosphates found in domestic sewage, thereby avoiding the eutrophication of water bodies as well as enabling the recovery and utilization of phosphorus resources.


Assuntos
Cério , Eichhornia , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Cinética , Fosfatos , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise
17.
Molecules ; 26(17)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34500595

RESUMO

Amine-containing drugs often show poor pharmacological properties, but these disadvantages can be overcome by using a prodrug approach involving self-immolative linkers. Accordingly, we designed l-lactate linkers as ideal candidates for amine delivery. Furthermore, we designed linkers bearing two different cargos (aniline and phenol) for preferential amine cargo release within 15 min. Since the linkers carrying secondary amine cargo showed high stability at physiological pH, we used our strategy to prepare phosphate-based prodrugs of the antibiotic Ciprofloxacin. Therefore, our study will facilitate the rational design of new and more effective drug delivery systems for amine-containing drugs.


Assuntos
Aminas/química , Preparações Farmacêuticas/química , Fosfatos/química , Pró-Fármacos/química , Antibacterianos/química , Ciprofloxacina/química , Sistemas de Liberação de Medicamentos/métodos , Concentração de Íons de Hidrogênio , Ácido Láctico/química
18.
Ecotoxicol Environ Saf ; 225: 112771, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34530258

RESUMO

Tri-ortho-cresyl phosphate (TOCP) has been used commercially as a plasticizer and a flame retardant, which has been reported to cause multiple toxicities in humans and other animals. However, the effect of TOCP on female reproductive system is still unclear. The aim of this investigation was to evaluate the reproductive toxicity of TOCP in female avian and investigate its molecular mechanism. In the current study, 50 adult hens were given a single oral dose of TOCP (750 mg/kg). Egg laid by the hens were harvested and counted. Egg quality is assessed by determining the shell strength and thickness. Samples of ovary, shell gland, and serum were collected on day 0, 2, 7, and 21 after the administration. The morphological and pathological changes in tissues were examined. Cell death, follicular development, and steroidogenesis were determined to assess the toxicity of TOCP on laying hens. The results showed that egg production, egg weight, and eggshell strength significantly decreased after TOCP exposure. The calcium levels in serum and eggshell decreased and the expression levels of the eggshell formation-related genes calbindin-D28k (CaBP-D28k) and carbonic anhydrase 2 (CA2) were downregulated. The inhibitory effects of TOCP on follicular development and steroidogenesis were observed with changes in the levels of the related proteins such as forkhead box O1 (FoxO1) and mothers against decapentaplegic homolog 2/3 (Smad2/3). Cell death was identified, which might lead to follicular development disorder. Taken together, TOCP reduced the quantity and quality of the eggs laid by the hens through disrupting follicular development, steroidogenesis, and shell gland function.


Assuntos
Galinhas , Casca de Ovo , Animais , Ovos , Feminino , Humanos , Ovário , Fosfatos
19.
Nano Lett ; 21(18): 7579-7586, 2021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34469158

RESUMO

Na-ion and K-ion batteries are promising alternatives for large-scale energy storage due to their abundance and low cost. Intercalation of these large ions could cause irreversible structural deformation and partial to complete amorphization in the crystalline electrodes. A lack of understanding of the dynamic changes in the amorphous nanostructure during battery operation is the bottleneck for further developments. Here, we report the utilization of in-operando digital image correlation and XRD techniques to probe dynamic changes in the amorphous phase of iron phosphate during potassium ion intercalation. In-operando XRD demonstrates amorphization in the electrode's nanostructure during the first charge and discharge cycle. Additionally, ex situ HR-TEM further confirms the amorphization after potassium-ion intercalation. An in situ strain analysis detects reversible deformations associated with redox reactions in the amorphous phases. Our approach offers new insights into the mechanism of ion intercalation in the amorphous nanostructure which are highly potent for the development of next-generation batteries.


Assuntos
Fosfatos , Potássio , Eletrodos , Íons , Ferro
20.
Bioresour Technol ; 341: 125894, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34523556

RESUMO

Phosphate additives especially superphosphate can reduce nitrogen loss, and increase phosphorus availability in composting. This study investigated the changes of different heavy metals fractions and their relationship with bacterial community and abiotic factors during pig manure composting with adding equimolar H3PO4, H2SO4 and K2HPO4. Results showed that both acidic and alkaline labile phosphate increased the potential ecological risk of heavy metals compared to control, but K2HPO4 decreased the accumulation of exchangeable Zn and Mn by 12% and 15% than that with H3PO4 and H2SO4 addition. Network analysis showed that K2HPO4 enhanced the proportion of negative links in bacterial species with heavy metals, but H3PO4 decreased the stability of bacterial network. Redundancy analysis demonstrated that pH was the key factor on metal speciation and risk with phosphate additives than bacterial role. The study presented theoretical basis for additive selection in controlling composting nitrogen fixation and environmental risk.


Assuntos
Compostagem , Metais Pesados , Animais , Esterco , Metais Pesados/análise , Fosfatos , Solo , Suínos
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