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1.
Artículo en Inglés | MEDLINE | ID: mdl-39075799

RESUMEN

INTRODUCTION: Transvenous lead extraction (TLE) is generally considered a safe procedure, albeit not without risks. While gender-based disparities have been noted in short-term outcomes following TLE, a notable gap exists in understanding the long-term consequences of this procedure. The objective of this analysis was to investigate sex differences in both acute and long-term outcomes among patients who underwent TLE at a tertiary referral center. METHODS: In this retrospective cohort study, consecutive patients who underwent TLE between January 2014 and January 2016 were enrolled. The primary outcome comprised a composite of all-cause mortality and need for repeated TLE procedures. Secondary outcomes included fluoroscopy time, lead extraction techniques, success rates, and major and minor complications. Results were compared between female and male cohorts. RESULTS: The study population comprised 191 patients (median age, 70 years), 29 (15.2%) being women and 162 men (84.8%). Study groups had similar baseline characteristics. Complete procedural success was achieved in 189 out of 191 patients (99.0%), with no significant difference observed between the two groups (p = .17). No major complications were reported in the total cohort. However, there was a significantly higher incidence of minor complications in women compared to men (17.2% vs. 2.5%, p < .01). Following a median follow-up of 6.5 years, the incidence of the primary composite outcome occurred similarly between the study groups (log-rank p = .68). CONCLUSION: Women who underwent TLE exhibited a significantly higher incidence of minor acute intra- and peri-procedural complications than men. However, no differences in long-term outcomes between genders were observed.

3.
Membranes (Basel) ; 14(6)2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38921501

RESUMEN

The combination of ion exchange membranes with carbon quantum dots (CQDs) is a promising field that could lead to significant advances in water treatment. Composite membranes formed by sulfonated poly(ether ether ketone) (SPEEK) with embedded CQDs were used for the detection and removal of heavy metal ions, such as lead and cadmium, from water. SPEEK is responsible for the capture of heavy metals based on the cation exchange mechanism, while CQDs detect their contamination by exhibiting changes in fluorescence. Water-insoluble "red" carbon quantum dots (rCQDs) were synthesized from p-phenylenediamine so that their photoluminescence was shifted from that of the polymer matrix. CQDs and the composites were characterized by several techniques: FTIR, Raman, UV/VIS, photoluminescence, XPS spectroscopies, and AFM microscopy. The heavy metal ion concentration was analyzed by inductively coupled plasma-optical emission spectroscopy (ICP-OES). The concentration ranges were 10.8-0.1 mM for Pb2+ and 10.0-0.27 mM for Cd2+. SPEEK/rCQDs showed a more pronounced turn-off effect for lead. The composite achieved 100% removal efficiency for lead and cadmium when the concentration was below a half of the ion exchange capacity of SPEEK. The regeneration of membranes in 1 M NaCl was also studied. A second order law was effective to describe the kinetics of the process.

4.
Environ Technol ; : 1-13, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38619982

RESUMEN

Microbial extracellular polymeric substances (EPS) have recently emerged as significant contributors in diverse biotechnological applications. Extracellular polymeric substances (EPS), produced by a Navicula salinicola strain, have been studied for potential applications in a specific heavy metal (lead (Pb II)) removal from wastewater. The optimisation of operational parameters, mainly pH, Pb and EPS concentrations, using the Box-Behnken design (BBD) was undertaken to enhance lead uptake. The higher Pb adsorption capacity reached 2211.029 mg/g. Hydroxyl, carbonyl, carboxyl, phosphoric, and sulfhydryl groups were identified quantitatively as potential sites for Pb adsorption. EPS exhibited a notable flocculation rate of 70.20% in kaolin clay at a concentration of 15 mg/L. They demonstrated an emulsifying activity greater than 88%, showcasing their versatile potential for both sedimentation processes and stabilising liquid-liquid systems. EPS could be excellent nonconventional renewable biopolymers for treating water and wastewater.

5.
Huan Jing Ke Xue ; 45(2): 862-872, 2024 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-38471925

RESUMEN

Calcium-containing biochar (ES-BC) was prepared by pyrolyzing eggshell and kitchen wastes, and the ES-BC composite was used to remove phosphate (marked as ES-BC/P). Based on the high affinity of phosphate and carbonate to lead, the ES-BC/P was then used to remove lead from the water. The results showed that, in the appropriate dosage, ES-BC/P could remove lead efficiently at different initial concentrations (1-100 mg·L-1), and the removal efficiency could reach to 99%. Meanwhile, the release of phosphorus could be ignored after the reaction. As ES-BC/P was alkaline, and the lead-containing solution was weakly acidic, the addition of ES-BC/P could adjust the pH of the system automatically. The reaction kinetics and isotherm experiments showed that the lead removal by ES-BC/P was mainly monolayer chemisorption with a maximum adsorption capacity of 493.12 mg·g-1 (318 K). The characterization results showed that lead was mainly removed through the ion exchanges of Pb2+ in the solution with Ca2+ in ES-BC/P. Then, the Pb2+ combined with CO32- and PO42- to form many precipitates, including Pb5(PO4)3OH, Pb10(PO4)6(OH)2, PbCO3, and Pb3(CO3)2(OH)2. In summary, the ES-BC/P material could achieve the efficient removal of lead from the water, thereby realizing the resource utilization of the wastes.

6.
Sci Rep ; 14(1): 4372, 2024 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-38388664

RESUMEN

Due to the characteristics of electrospun nanofibers (NFs), they are considered a suitable substrate for the adsorption and removal of heavy metals. Electrospun nanofibers are prepared based on optimized polycaprolactone (PCL, 12 wt%) and polyacrylic acid (PAA, 1 wt%) polymers loaded with graphene oxide nanoparticles (GO NPs, 1 wt%). The morphological, molecular interactions, crystallinity, thermal, hydrophobicity, and biocompatibility properties of NFs are characterized by spectroscopy (scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, Thermogravimetric analysis), contact angle, and MTT tests. Finally, the adsorption efficacy of NFs to remove lead (Pb2+) from water and apple juice samples was determined using inductively coupled plasma optical emission spectroscopy (ICP-OES). The average diameter for PCL, PCL/PAA, and PCL/PAA/GO NFs was 137, 500, and 216 nm, respectively. Additionally, the contact angle for PCL, PCL/PAA, and PCL/PAA/GO NFs was obtained at 74.32º, 91.98º, and 94.59º, respectively. The cytotoxicity test has shown non-toxicity for fabricated NFs against the HUVEC endothelial cell line by more than 80% survival during 72 h. Under optimum conditions including pH (= 6), temperature (25 °C), Pb concentration (25 to 50 mg/L), and time (15 to 30 min), the adsorption efficiency was generally between 80 and 97%. The adsorption isotherm model of PCL/PAA/GO NFs in the adsorption of lead metal follows the Langmuir model, and the reaction kinetics follow the pseudo-second-order. PCL/PA/GO NFs have shown adsorption of over 80% in four consecutive cycles. The adsorption efficacy of NFs to remove Pb in apple juice has reached 76%. It is appropriate and useful to use these nanofibers as a high-efficiency adsorbent in water and food systems based on an analysis of their adsorption properties and how well they work.


Asunto(s)
Resinas Acrílicas , Agua Potable , Grafito , Malus , Nanofibras , Poliésteres , Contaminantes Químicos del Agua , Agua Potable/análisis , Nanofibras/toxicidad , Nanofibras/química , Plomo/toxicidad , Plomo/análisis , Adsorción , Contaminantes Químicos del Agua/análisis , Cinética , Espectroscopía Infrarroja por Transformada de Fourier
7.
Environ Res ; 249: 118360, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38325779

RESUMEN

For human health and environment safety, it is of great significance to develop novel materials with high effectiveness for removal of lead from not only aqueous solutions but also human body and traditional Chinese medicines. Here, functional kiwi peel composite, manganese dioxide decorated kiwi peel powder (MKPP), is proposed for the removal of Pb2+ effectively. The adsorption of Pb2+ in aqueous solution is a highly selective and endothermic process and kinetically follows a pseudo-second-order model, which can reach equilibrium with the capacity of 192.7 mg/g within 10 min. Comprehensive factors of hydration energy, charge-to-radius ratio and softness of Pb2+ make a stronger affinity between MKPP and Pb2+. The possible adsorption mechanism involves covalent bond, electrostatic force and chelation, etc. MKPP can be efficiently regenerated and reused with high adsorption efficiency after five cycles. Besides, MKPP can remove over 97% of Pb2+ from real water samples. MKPP can also alleviate lead poisoning to a certain extent and make the Pb level of TCM extract meet the safety standard. This work highlights that MKPP is a promising adsorbent for the removal of Pb2+ and provides an efficient strategy for reusing kiwi peel as well as dealing with the problem of Pb pollution.


Asunto(s)
Medicamentos Herbarios Chinos , Plomo , Compuestos de Manganeso , Óxidos , Contaminantes Químicos del Agua , Plomo/aislamiento & purificación , Plomo/química , Compuestos de Manganeso/química , Adsorción , Óxidos/química , Medicamentos Herbarios Chinos/química , Humanos , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Medicina Tradicional China , Purificación del Agua/métodos
8.
Int J Biol Macromol ; 255: 128032, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37977462

RESUMEN

Biological synthesis of nanoparticles is cost-effective as well as safer than physical and chemical methods. This study focuses on the biological synthesis of silver nanoparticles using Glutamicibacter uratoxydans which remains still unexplored. The synthesized silver nanoparticles are encapsulated with chitosan to prepare nanobiocomposite. Actinobacteria were isolated from mesophilic soil and screened for heavy metal resistance. The potent heavy metal resistant isolate was identified by 16SrRNA sequencing and used for the biological synthesis of silver particles. The characterization of chitosan- silver nano-bio composite was carried out by UV-Vis spectroscopy, FTIR spectroscopy, and XRD. Morphology was analyzed by scanning electron microscopy. The particle size and stability were studied using Dynamic light scattering and Zeta potential analysis. The nano-bio composite was tested for lead removal efficiency and antibiofilm activity. The potent isolate was identified as Glutamicibacter uratoxydans and it was named as Glutamicibacter uratoxydans VRAK 24. The UV spectra showed maximum absorbance at 410 nm. The FTIR spectra and XRD confirmed chitosan encapsulation with silver nanoparticle. The size of nanobiocomposite was found to be 0.376. The stability of nanobiocomposite recorded a zeta potential value of -5.37 mV. The lead removal efficiency was found to be 87.69 %. In addition, the nanobiocomposite exhibited highest anti-biofilm activity against S.aureus when compared to E.coli. The research findings, concluded that the synthesized nanobiocomposite showed better anti-biofilm activity. Also, nanobiocomposite was found to be a good adsorbent for the removal of heavy metal lead.


Asunto(s)
Quitosano , Nanopartículas del Metal , Plata/farmacología , Plata/química , Antibacterianos/química , Nanopartículas del Metal/química , Quitosano/farmacología , Quitosano/química , Espectroscopía Infrarroja por Transformada de Fourier , Biopelículas , Pruebas de Sensibilidad Microbiana
9.
J Environ Sci (China) ; 139: 281-292, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38105055

RESUMEN

Realizing campus sustainability requires the environmental-friendly and economical treatment of tremendous fallen leaves. Producing fallen leaf biochar at a low temperature is a candidate approach. In this study, six common types of fallen leaves on the campus were pyrolyzed at 300 °C. The obtained biochars were characterized and the adsorption mechanisms of lead (Pb) by the fallen leaf biochars were investigated. The adsorption capacity of leaf biochar for Pb was relatively high, up to 209 mg/g (Yulania denudata leaf biochar). Adsorption of Pb onto active sites was the rate-limiting step for most leaf biochars. But for Platanus leaf biochar, intraparticle diffusion of Pb2+ dominated owing to the lowest adsorption capacity. However, the highest exchangeable Pb fraction (27%) indicated its potential for removing aqueous Pb2+. Ginkgo and Prunus cerasifera leaf biochar immobilized Pb by surface complexation and precipitation as lead oxalate. Hence, they were suitable for soil heavy metal remediation. This study shed the light on the sustainable utilization of campus fallen leaves and the application of fallen leaf biochars in heavy metal remediation.


Asunto(s)
Plomo , Metales Pesados , Temperatura , Pirólisis , Carbón Orgánico/química , Hojas de la Planta , Adsorción
10.
Environ Sci Pollut Res Int ; 30(57): 120461-120471, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37940829

RESUMEN

Lead, a toxic heavy metal present in soil, hampers biological activities and affects the metabolism of plants, animals, and human beings. Its higher concentration may disturb the various physio-chemical processes, which result in stunted and poor plant growth. An interactive approach of plant growth promoting rhizobacteria (PGPR) and L-tryptophan can be used to mitigate the lethal effects of lead. A pot experiment was conducted, and two weeks before sowing, the level of lead (300 mg kg-1) was maintained by spiking the PbCl2 salt. Pseudomonas fluorescens and L-tryptophan were applied individually as well as in combination to segregate the effect of both in contaminated soil under a completely Randomized Design (CRD). Statistical analysis revealed that plant growth was significantly reduced up to 22% due to lead contamination. However, the interactive approach of PGPR and L-tryptophan significantly improved the plant growth, physiology, and yield with relative productive index (RPI) under a lead-stressed environment. Moreover, integrated use of PGPR and L-tryptophan demonstrated a considerable increase (22%) in lead removal efficiency (LRE) by improving bioconcentration factor (BCF) and translocation factor (TF) for shoot without increasing the lead concentration in achenes. The reduced lead concentration in achene was due to its immobilization in shoot and root by negatively charged particles and improved the lead sequestration in vegetative parts which abridged the translocation of lead into achenes.


Asunto(s)
Alphaproteobacteria , Helianthus , Pseudomonas fluorescens , Contaminantes del Suelo , Animales , Humanos , Plomo/análisis , Pseudomonas fluorescens/metabolismo , Triptófano , Biodegradación Ambiental , Alphaproteobacteria/metabolismo , Suelo , Contaminantes del Suelo/análisis
11.
Molecules ; 28(21)2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37959815

RESUMEN

In this study, phosphoric acid was used to attach anions to the weak interlayer structure of sericite, one of the clay minerals composed of a tetrahedral structure of silicate, to increase the adsorption capacity of cations. Natural sericite beads (NSB) and activated sericite beads with phosphoric acid (PSB) were prepared as beads in order to increase reusability and facilitate the separation of adsorbates and adsorbents. Using this, lead (Pb(II)) removal efficiency from an aqueous solution was comparatively analyzed. The pHpzc was 6.43 in NSB but lowered to 3.96 in PSB, confirming that more acidic functional groups were attached to the PSB surface. According to FT-IR analysis, P=O, P-O-C, P=OOH and P-O-P bonds appeared on the surface of the PSB adsorbent, and the peaks of carboxyl groups and OH-groups were large and broad. The maximum adsorption capacity of Langmuir was 52.08 mg/g for NSB and 163.93 mg/g for PSB. The adsorption process was close to physical adsorption for NSB and chemical adsorption for PSB, and both adsorbents were endothermic reactions in nature in that the higher the temperature, the higher the adsorption efficiency. The adsorption mechanism of Pb(II) to PSB was achieved by ion exchange, electrostatic interaction, hydrogen bonding, and complexation. The adsorption of Pb(II) using PSB was not significantly affected by the adsorption of competing ions and showed a high adsorption efficiency of 94% in reuse up to 6 times. This confirms the favorable feasibility of removing Pb(II) from industrial wastewater using PSB.

12.
Int J Mol Sci ; 24(18)2023 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-37762092

RESUMEN

Microporous sodium titanosilicate, Na2TiSiO5, has been successfully prepared using the sol-gel method. The structural and morphological characterization of synthesized product has been made via thermal analyses (TG-DTG), X-ray diffraction (XRD), and electron microscopy (SEM and TEM). Adsorption properties of the synthesized Na2TiSiO5 nanopowder for Pb(II) removal of aqueous media was investigated in different experimental conditions such as the contact time, the initial metal concentration, the pH, and the temperature. The Pb(II) adsorption on Na2TiSiO5 was discussed according to the kinetics and thermodynamics models. The adsorption kinetics of Pb(II) have been better described by the PS-order kinetic model which has the highest fitting correlation coefficients (R2: 0.996-0.999) out of all the other models. The adsorption results have been successfully fitted with the Langmuir and Redlich-Paterson models (R2: 0.9936-0.9996). The calculated thermodynamic parameters indicate that the Pb(II) adsorption is an endothermic process, with increased entropy, having a spontaneous reaction. The results have revealed a maximum adsorption capacity of 155.71 mg/g at 298 K and a very high adsorption rate at the beginning, more than 85% of the total amount of Pb(II) being removed within the first 120 min, depending on the initial concentration.


Asunto(s)
Plomo , Sodio , Termodinámica , Entropía , Temperatura
13.
Am J Cardiol ; 203: 444-450, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37542954

RESUMEN

The outcomes of leadless pacemaker (LP) implantation after transvenous lead removal (TLR) of infected cardiac implantable electronic devices (CIEDs) are not well-established. This study sought to describe the outcomes of LP implantation after TLR of infected CIED. We conducted a literature search using PubMed and Embase for a combination of terms including LP implantation, transvenous lead extraction, TLR, transvenous lead explant, infected CIED, infected pacemaker, and infected implantable cardioverter defibrillator. The inclusion criterion was LP implantation after TLR of infected CIED. The exclusion criterion was TLR for noninfectious reasons. Study end points included procedural complications and LP infection during follow-up. Of 132 publications reviewed, 13 studies with a total of 253 patients (74 ± 14 years of age, 174 [69%] males) were included. The most common indication of the initial device implantations was a high-degree atrioventricular block (n = 100 of 253, 39.5%). Of the 253 patients included, 105 patients (41.5%) underwent concomitant LP implantation during the TLR procedure, and 36 patients (14.2%) had temporary transvenous pacing as a bridge from TLR to LP implantation. Of the 148 patients with data on the type of CIED infection, 56.8% had systemic CIED infection and 43.2% had isolated pocket infection. Staphylococcus aureus was the most common causative organism in 33% of the reported patients. The LP was implanted an average of 5.4 ± 10.7 days after TLR of infected CIED. During the LP implantation, 1 patient (0.4%) had unsuccessful implantation because of an intraprocedural complication requiring sternotomy. After LP implantation, 2 patients (0.8%) developed groin hematoma, 2 patients (0.8%) developed femoral arteriovenous fistula, and 1 patient (0.4%) developed pericardial effusion requiring pericardiocentesis. During a mean follow-up of 11.3 ± 10.6 months, 3 patients (1.2%) developed pacemaker syndrome, 1 patient (0.4%) developed acute on chronic heart failure exacerbation, and only 1 patient (0.4%) developed LP-related infection requiring LP retrieval. This study suggests that LP implant is feasible and safe after removal of infected CIED with cumulative adverse events at 4% and a reinfection rate of 0.4%. Large prospective studies are needed to better evaluate the best timing of LP implantation after TLR of an infected CIED.


Asunto(s)
Desfibriladores Implantables , Marcapaso Artificial , Infecciones Relacionadas con Prótesis , Masculino , Humanos , Femenino , Resultado del Tratamiento , Infecciones Relacionadas con Prótesis/epidemiología , Infecciones Relacionadas con Prótesis/terapia , Infecciones Relacionadas con Prótesis/etiología , Remoción de Dispositivos/efectos adversos , Marcapaso Artificial/efectos adversos , Desfibriladores Implantables/efectos adversos , Estudios Retrospectivos
14.
Environ Res ; 236(Pt 1): 116731, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37517492

RESUMEN

Biochar derived from soybean straw with AAEMs (alkali and alkaline earth metals) enrichment could efficiently remove heavy metals from contaminated water. In this study, the influences of pyrolysis temperature on the physicochemical property and adsorption performance of soybean straw biochar were investigated. The contributions of different adsorption mechanisms were analyzed quantitatively. The results show that the soybean straw biochar exhibits excellent Pb2+ adsorption performance (157.2-227.2 mg g-1), with an order of BC800 > BC400 > BC600 > BC700 > BC500. The mechanisms of metal ion exchange (37.49%-72.58%) and precipitation with minerals (22.38%-58.03%) mainly control the Pb2+ adsorption, whereas complexation with organic functional groups (OFGs) and cation-Cπ interaction make the less contribution. The order of cation exchange capacity (CEC) is BC400 > BC800 > BC700 > BC600 > BC500, showing a high correlation (0.965) with the contribution of metal ion exchange with AAEMs. Moreover, Ca exhibits the strongest exchange capacity. The contribution of precipitation is consistent with the variation of soluble CO32- content in biochar. These results suggest that soybean straw biochar rich in AAEMs is a prospective adsorbent for Pb2+ elimination.


Asunto(s)
Carbón Orgánico , Plomo , Adsorción , Carbón Orgánico/química , Agua , Cationes
15.
Nanomaterials (Basel) ; 13(10)2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-37242100

RESUMEN

Real water remediation is an important issue that requires the development of novel adsorbents with remarkable adsorption properties, permitting reusability. In this work, the surface and adsorption properties of bare magnetic iron oxide nanoparticles were systematically studied, before and after the application of a maghemite nanoadsorbent in two real Peruvian effluents severely contaminated with Pb(II), Pb(IV), Fe(III), and others. We were able to describe the Fe and Pb adsorption mechanisms that occurred at the particle surface. 57Fe Mössbauer and X-ray photoelectron spectroscopy results together with kinetic adsorption analyses gave evidence for two involved surface mechanisms: (i) surface deprotonation of maghemite nanoparticles (isoelectric point of pH = 2.3), forming Lewis sites bonding Pb complexes; and (ii) the formation of a thin inhomogeneous secondary layer of iron oxyhydroxide and adsorbed Pb compounds, as favored by surface physicochemical conditions. The magnetic nanoadsorbent enhanced the removal efficiency to values of ca. 96% and provided adsorptive properties with reusability due to the conserved morphological, structural, and magnetic properties. This makes it favorable for large-scale industrial applications.

16.
Nanomaterials (Basel) ; 13(8)2023 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-37110986

RESUMEN

Zeolitic imidazolate frameworks (ZIFs) are increasingly gaining attention in many application fields due to their outstanding porosity and thermal stability, among other exceptional characteristics. However, in the domain of water purification via adsorption, scientists have mainly focused on ZIF-8 and, to a lesser extent, ZIF-67. The performance of other ZIFs as water decontaminants is yet to be explored. Hence, this study applied ZIF-60 for the removal of lead from aqueous solutions; this is the first time ZIF-60 has been used in any water treatment adsorption study. The synthesized ZIF-60 was subjected to characterization using FTIR, XRD and TGA. A multivariate approach was used to investigate the effect of adsorption parameters on lead removal and the findings revealed that ZIF-60 dose and lead concentration are the most significant factors affecting the response (i.e., lead removal efficiency). Further, response surface methodology-based regression models were generated. To further explore the adsorption performance of ZIF-60 in removing lead from contaminated water samples, adsorption kinetics, isotherm and thermodynamic investigations were conducted. The findings revealed that the obtained data were well-fitted by the Avrami and pseudo-first-order kinetic models, suggesting that the process is complex. The maximum adsorption capacity (qmax) was predicted to be 1905 mg/g. Thermodynamic studies revealed an endothermic and spontaneous adsorption process. Finally, the experimental data were aggregated and used for machine learning predictions using several algorithms. The model generated by the random forest algorithm proved to be the most effective on the basis of its significant correlation coefficient and minimal root mean square error (RMSE).

17.
J Environ Manage ; 339: 117925, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37060696

RESUMEN

For fabricating a membrane with hydrophilic and complexing agent groups, a new dithiocarbamate-based polymer (DTCP) containing dithiocarbamate, thioamide, and ethereal oxygen groups was synthesized and blended in polysulfone (PSF) matrix with 1, 2, 5, and 10 wt% proportion. The membranes were produced by the nonsolvent induced phase separation method. For DTCP characterization, NMR, FTIR, TGA and GPC techniques were used. SEM images show that no morphological change can be seen even in 10 wt% blended membranes. AFM surface images show that the roughness of 5 and 10 wt% membranes extremely increased. The performance of the DTCP/PSF membranes were investigated in the separation of lead ions and Reactive Yellow 39 dye from the contaminated water. The outcomes indicated that by increasing the amount of DTCP up to 10 wt%, the pure water flux, bovine serum albumin flux, and the lead removal increased very efficiently compared to the bare one. Blending of more than 1 wt% DTCP, cause to removal of 99.6% lead ions. The water contact angle decreased by the adding of DTCP, caused to increase fouling resistance. The results of this research shows that the synthesized DTCP can be used as a good additive for improving membrane permeability, anti-fouling and especially heavy metal removal efficiency.


Asunto(s)
Purificación del Agua , Purificación del Agua/métodos , Membranas Artificiales , Plomo , Agua/química , Polímeros
18.
Nanomaterials (Basel) ; 13(6)2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36985971

RESUMEN

In this work, polyethyleneimine-grafted graphene oxide (PEI/GO) is synthesized using graphene, polyethyleneimine, and trimesoyl chloride. Both graphene oxide and PEI/GO are characterized by a Fourier-transform infrared (FTIR) spectrometer, a scanning electron microscope (SEM), and energy-dispersive X-ray (EDX) spectroscopy. Characterization results confirm that polyethyleneimine is uniformly grafted on the graphene oxide nanosheets and, thus, also confirm the successful synthesis of PEI/GO. PEI/GO adsorbent is then evaluated for the removal of lead (Pb2+) from aqueous solutions, and the optimum adsorption is attained at pH 6, contact time of 120 min, and PEI/GO dose of 0.1 g. While chemosorption is dominating at low Pb2+ concentrations, physisorption is dominating at high concentrations and the adsorption rate is controlled by the boundary-layer diffusion step. In addition, the isotherm study confirms the strong interaction between Pb2+ ions and PEI/GO and reveals that the adsorption process obeys well the Freundlich isotherm model (R2 = 0.9932) and the maximum adsorption capacity (qm) is 64.94 mg/g, which is quite high compared to some of the reported adsorbents. Furthermore, the thermodynamic study confirms the spontaneity (negative ΔG° and positive ΔS°) and the endothermic nature (ΔH° = 19.73 kJ/mol) of the adsorption process. The prepared adsorbent (PEI/GO) offers a potential promise for wastewater treatment because of its fast and high uptake removal capacity and could be used as an effective adsorbent for the removal of Pb2+-ions and other heavy metals from industrial wastewater.

19.
Membranes (Basel) ; 13(2)2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36837673

RESUMEN

Lead (Pb) exposure can be harmful to public health, especially through drinking water. One of the promising treatment methods for lead contaminated water is the adsorption-filtration method. To ensure the cost-effectiveness of the process, naturally derived adsorbent shall be utilised. In this study, hydroxyapatite particles, Ca10(PO4)6(OH)2 (HAP) derived from waste cockle shell, were incorporated into the outer layer of polysulfone/HAP (PSf/HAP) dual-layer hollow fibre (DLHF) membrane to enhance the removal of lead from the water source due to its hydrophilic nature and excellent adsorption capacity. The PSf/HAP DLHF membranes at different HAP loadings in the outer layer (0, 10, 20, 30 and 40 wt%) were fabricated via the co-extrusion phase inversion technique. The performance of the DLHF membranes was evaluated in terms of pure water flux, permeability and adsorption capacity towards lead. The results indicated that the HAP was successfully incorporated into the outer layer of the membrane, as visibly confirmed by microscopic analysis. The trend was towards an increase in pure water flux, permeability and lead adsorption capacity as the HAP loading increased to the optimum loading of 30 wt%. The optimized DLHF membrane displayed a reduced water contact angle by 95%, indicating its improved surface hydrophilicity, which positively affects the pure water flux and permeability of the membrane. Furthermore, the DLHF membrane possessed the highest lead adsorption capacity, 141.2 mg/g. The development of a hybrid inorganic-organic DLHF membrane via the incorporation of the naturally derived HAP in the outer layer is a cost-effective approach to treat lead contaminated water.

20.
Int J Cardiol ; 378: 32-38, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36841289

RESUMEN

BACKGROUND: Transvenous lead extraction (TLE) has shown a safe and efficacy profile in the intraoperative and short-term setting; however, data on long-term outcomes are limited. OBJECTIVE: The purpose of this study was to assess long-term outcomes and prognostic factors in patients who underwent TLE. METHODS: Consecutive patients with cardiac implantable electronic device (CIED) who underwent TLE between 2014 and 2016 were retrospectively studied. The primary outcome was the composite endpoint of death and repeated TLE stratified by infective/non-infective indication. Individual components of the primary outcome were also evaluated. RESULTS: One hundred ninety-one patients were included in the analysis, 50% extracted for CIED-related infection. Complete procedural success was achieved in 189 patients (99%) with no major acute complications. After a median of 6.5 years, infection indication was associated with significantly lower event-free survival (67% vs. 83% non-infection group, adjusted hazard ratio [aHR] 1.97, 95% confidence interval [CI] 1.02-3.81, p = 0.04). All-cause mortality rate was higher in the TLE infection group (30% vs. 10%, p < 0.01). The rate of repeated TLE did not differ between groups (4% vs. 7%, p = 0.62). Among patients who had TLE for infection, the presence of vegetation (aHR 2.56; 95%CI 1.17-5.63, p = 0.02) and positive blood cultures (aHR 2.64; 95%CI 1.04-6.70, p = 0.04) were independently associated with the primary outcome. CONCLUSION: Patients who underwent TLE for CIED-related infection exhibit a high mortality risk during long-term follow-up. Vegetation and positive blood cultures in patients with CIED-related infection are associated with a worse prognosis regardless of successful and uncomplicated TLE.


Asunto(s)
Desfibriladores Implantables , Marcapaso Artificial , Humanos , Desfibriladores Implantables/efectos adversos , Estudios Retrospectivos , Centros de Atención Terciaria , Remoción de Dispositivos , Marcapaso Artificial/efectos adversos , Resultado del Tratamiento
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