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1.
Inorg Chem ; 63(16): 7464-7472, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38598182

RESUMO

Uranium accumulation in the kidneys and bones following internal contamination results in severe damage, emphasizing the pressing need for the discovery of actinide decorporation agents with efficient removal of uranium and low toxicity. In this work, cinnamic acid (3-phenyl-2-propenoic acid, CD), a natural aromatic carboxylic acid, is investigated as a potential uranium decorporation ligand. CD demonstrates markedly lower cytotoxicity than that of diethylenetriaminepentaacetic acid (DTPA), an actinide decorporation agent approved by the FDA, and effectively removes approximately 44.5% of uranyl from NRK-52E cells. More importantly, the results of the prompt administration of the CD solution remove 48.2 and 27.3% of uranyl from the kidneys and femurs of mice, respectively. Assessments of serum renal function reveal the potential of CD to ameliorate uranyl-induced renal injury. Furthermore, the single crystal of CD and uranyl compound (C9H7O2)2·UO2 (denoted as UO2-CD) reveals the formation of uranyl dimers as secondary building units. Thermodynamic analysis of the solution shows that CD coordinates with uranyl to form a 2:1 molar ratio complex at a physiological pH of 7.4. Density functional theory (DFT) calculations further show that CD exhibits a significant 7-fold heightened affinity for uranyl binding in comparison to DTPA.


Assuntos
Cinamatos , Urânio , Cinamatos/química , Cinamatos/farmacologia , Animais , Ligantes , Camundongos , Urânio/química , Urânio/metabolismo , Urânio/toxicidade , Rim/efeitos dos fármacos , Rim/metabolismo , Linhagem Celular , Teoria da Densidade Funcional , Ratos , Estrutura Molecular , Sobrevivência Celular/efeitos dos fármacos , Quelantes/química , Quelantes/farmacologia , Quelantes/síntese química
2.
Opt Express ; 31(2): 2792-2806, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785285

RESUMO

Countless waveguides have been designed based on four basic bends: circular bend, sine/cosine bend, Euler bend (developed in 1744) and Bezier bend (developed in 1962). This paper proposes an n-adjustable (NA) bend, which has superior properties compared to other basic bends. Simulations and experiments indicate that the NA bends can show lower losses than other basic bends by adjusting n values. The circular bend and Euler bend are special cases of the proposed NA bend as n equals 0 and 1, respectively. The proposed bend are promising candidates for low-loss compact photonic integrated circuits.

3.
Langmuir ; 39(36): 12910-12919, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37649325

RESUMO

The effective capture and deposition of radioactive iodine in the spent fuel reprocessing process is of great importance for nuclear safety and environmental protection. Three-dimensional (3D) fiber felt with structural diversity and tunability is applied as an efficient adsorbent with easy separation for iodine capture. Here, a bismuth-based silica aerogel fiber felt (Bi@SNF) was synthesized using a facile hydrothermal method. Abundant and homogeneous Bi nanoparticles greatly enhanced the adsorption and immobilization of iodine. Notably, Bi@SNF demonstrated a high capture capacity of 982.9 mg/g by forming stable BiI3 and Bi5O7I phases, which was about 14 times higher than that of the unloaded material. Fast uptake kinetics and excellent resistance to nitric acid and radiation were exhibited as a result of the 3D porous interconnected network and silica aerogel fiber substrate. Adjustable size and easy separation and recovery give the material potential as a radioactive iodine gas capture material.

4.
Inorg Chem ; 62(14): 5799-5809, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-36974005

RESUMO

The capture of the radionuclides strontium and cesium is of great importance to the environment, human health, and the sustainable development of nuclear energy, and zirconium phosphate with excellent ion exchange capacity has potential application in this field. In this work, we organically granulated zirconium phosphate to induce the formation of composite bead materials (CA@ZrP) with a calcium-containing phase with selectivity for Sr2+ and Cs+ higher than that of pure ZrP in low-pH environments and competing ionic environments. The adsorption performance of the material was systematically investigated. It was concluded that the adsorption performance of CA@ZrP improved with an increase in temperature, and under the dynamic adsorption experimental conditions, the treatment capacity of CA@ZrP for Sr2+ and Cs+ reached 404.79 and 302.2 bed volumes, respectively. The systematic study and characterization showed that the generation of the calcium-containing phase [Ca0.55ZrH0.9(PO4)2] promoted the exchange of Ca2+ with Sr2+ and Cs+, thus improving the selectivity of the composite beads. The highly selective composite bead material can be prepared in batches and easily recycled, providing a new idea for practical engineering applications.

5.
Inorg Chem ; 61(49): 20133-20143, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36426769

RESUMO

Effective capture of radioactive iodine is highly desirable for decontamination purposes in spent fuel reprocessing. Cu-based adsorbents with a low cost and high chemical affinity for I2 molecules act as a decent candidate for iodine elimination, but the low utilization and stability remain a significant challenge. Herein, a facile in situ confined synthesis strategy is developed to design and synthesize a copper-encapsulated flaky silicalite-1 (Cu@FSL-1) zeolite with a thickness of ≤300 nm. The maximum iodine uptake capacity of Cu@FSL-1 can reach 625 mg g-1 within 45 min, which is 2 times higher than that of a commercial silver-exchanged zeolite even after nitric acid and NOX treatment. The Cu nanoparticles (NPs) confined within the zeolite exert superior iodine adsorption and immobilization properties as well as high stability and fast adsorption kinetics endowed by the all-silica zeolite matrix. This study provides new insight into the design and controlled synthesis of zeolite-confined metal adsorbents for efficient iodine capture from gaseous radioactive streams.


Assuntos
Iodo , Neoplasias da Glândula Tireoide , Zeolitas , Humanos , Zeolitas/química , Cobre/química , Radioisótopos do Iodo , Prata
6.
Support Care Cancer ; 30(4): 3279-3289, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34984549

RESUMO

PURPOSE: Nutrition education andcounseling is the first-line approach in nutritional support for adult cancer patients; however, it is not well implemented in many clinical settings. This study aims to determine the effect of an evidence-based nutrition education and counseling (NEC) program on nutrition status among cancer patients receiving radiotherapy. SUBJECTS/METHODS: This cluster-randomized clinical trial enrolled cancer patients receiving radiotherapy from ten radiotherapy units in three hospitals. Randomization was conducted at the unit level (five units into the NEC group and five units into the usual care group). The primary outcome was nutrition status after radiotherapy measured by the Patient-Generated Subjective Global Assessment (PG-SGA). Secondary outcomes included nutrition-related blood biomarkers after radiotherapy and the use of artificial nutrition and treatment interruption during radiotherapy. RESULTS: A total of 468 patients were enrolled (241 in the NEC and 227 in the usual care group); 196 patients were female with a mean age (SD) of 59.8 (11.9). No difference was found between the NEC and usual care groups in nutrition status and blood biomarkers at baseline. After radiotherapy, patients in the NEC group had lower PG-SGA scores (5.6 vs 6.9; MD = -1.3, p < 0.001) and lower malnutrition rate (56.0% vs 70.5%; OR = 0.5; p = 0.004) compared with the usual care group. The usages of artificial nutrition and treatment interruption during radiotherapy and the level of blood biomarkers after radiotherapy did not differ between groups. CONCLUSIONS: Nutrition education and counseling is an effective approach in reducing malnutrition and can be generalized to multiple radiotherapy settings. REGISTERED UNDER CLINICALTRAILS. GOV IDENTIFIER NO: None.


Assuntos
Desnutrição , Neoplasias , Adulto , Aconselhamento , Feminino , Humanos , Desnutrição/complicações , Neoplasias/complicações , Neoplasias/radioterapia , Avaliação Nutricional , Estado Nutricional , Qualidade de Vida
7.
Sensors (Basel) ; 22(22)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36433312

RESUMO

Expendable current profiler (XCP) is one of the most vital devices detecting ocean currents. Compared with other methods, the expendable feature makes trials with XCP much faster and more hidden, while the accuracy of XCP is considerably influenced by electromagnetic noise all around. Aiming at researching the influence and reducing the noise, this study carried out laboratory simulation experiments. The designed laboratory experiments mainly have a self-developed rotation gear, an XCP prototype, a plastic flume, and two copper plates as power. Firstly, these experiments analyzed the main sources of electromagnetic noise for XCP detection. Secondly, we built a noise simulation environment and conducted XCP detection experiments under different noise in the flume. The data obtained by XCP were transmitted to the computer to be stored and processed. The results show the internal noise impact on XCP is significantly less than the external. For an excitation power of 1 mV, the offset of theoretical and actual data brought by internal noise is 12 times smaller than external and can be corrected.

8.
Dig Dis Sci ; 66(9): 3002-3014, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-32974809

RESUMO

BACKGROUND AND AIMS: In the present study, we investigated the differentially expressed genes (DEGs), pathways and immune cell infiltration characteristics of pediatric and adult ulcerative colitis (UC). METHODS: We conducted DEG analysis using the microarray dataset GSE87473 containing 19 pediatric and 87 adult UC samples downloaded from the Gene Expression Omnibus. Gene ontology and pathway enrichment analyses were conducted using Metascape. We constructed the protein-protein interaction (PPI) network and the drug-target interaction network of DEGs and identified hub modules and genes using Cytoscape and analyzed immune cell infiltration in pediatric and adult UC using CIBERSORT. RESULTS: In total, 1700 DEGs were screened from the dataset. These genes were enriched mainly in inter-cellular items relating to cell junctions, cell adhesion, actin cytoskeleton and transmembrane receptor signaling pathways and intra-cellular items relating to the splicing, metabolism and localization of RNA. CDC42, POLR2A, RAC1, PIK3R1, MAPK1 and SRC were identified as hub DEGs. Immune cell infiltration analysis revealed higher proportions of naive B cells, resting memory T helper cells, regulatory T cells, monocytes, M0 macrophages and activated mast cells in pediatric UC, along with lower proportions of memory B cells, follicular helper T cells, γδ T cells, M2 macrophages, and activated dendritic cells. CONCLUSIONS: Our study suggested that hub genes CDC42, POLR2A, RAC1, PIK3R1, MAPK1 and SRC and immune cells including B cells, T cells, monocytes, macrophages and mast cells play vital roles in the pathological differences between pediatric and adult UC and may serve as potential biomarkers in the diagnosis and treatment of UC.


Assuntos
Colite Ulcerativa , Biologia Computacional/métodos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Transdução de Sinais/genética , Adulto , Biomarcadores , Criança , Colite Ulcerativa/sangue , Colite Ulcerativa/genética , Colite Ulcerativa/patologia , Perfilação da Expressão Gênica/métodos , Humanos , Imunidade Celular/fisiologia , Comunicação Parácrina/fisiologia
9.
Int J Cancer ; 147(12): 3297-3304, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-32449165

RESUMO

Sirtuin 2 (SIRT2) belongs to the sirtuins family. It exists in many tissues and organs of the human body and regulates a wide range of biological functions. Studies have found that the abnormal expression of SIRT2 was associated with a variety of malignant tumors. SIRT2 possesses an important role in tumorigenesis, with both tumor-promoting and tumor-suppressing function. However, the mechanisms in which SIRT2 plays the roles in cancer are still controversial. This article reviews the role and molecular mechanism of SIRT2 in tumor evolution, and provides ideas for future research in this field, to guide the targeted therapy and drug development of related malignancies.


Assuntos
Neoplasias/metabolismo , Sirtuína 2/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Evolução Clonal , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico
10.
Phys Rev Lett ; 124(8): 083901, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32167354

RESUMO

Exceptional points (EPs), branch points of complex energy surfaces at which eigenvalues and eigenvectors coalesce, are ubiquitous in non-Hermitian systems. Many novel properties and applications have been proposed around the EPs. One of the important applications is to enhance the detection sensitivity. However, due to the lack of single-handed superchiral fields, all of the proposed EP-based sensing mechanisms are only useful for the nonchiral discrimination. Here, we propose theoretically and demonstrate experimentally a new type of EP, which is called a radiation vector EP, to fulfill the homogeneous superchiral fields for chiral sensing. This type of EP is realized by suitably tuning the coupling strength and radiation losses for a pair of orthogonal polarization modes in the photonic crystal slab. Based on the unique modal-coupling property at the vector EP, we demonstrate that the uniform superchiral fields can be generated with two beams of lights illuminating the photonic crystal slab from opposite directions. Thus, the designed photonic crystal slab, which supports the vector EP, can be used to perform surface-enhanced chiral detection. Our findings provide a new strategy for ultrasensitive characterization and quantification of molecular chirality, a key aspect for various bioscience and biomedicine applications.

11.
Andrologia ; 52(2): e13490, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31782182

RESUMO

To compare the difference of mean platelet volume (MPV), platelet lymphocyte ratio (PLR), neutrophil-lymphocyte ratio (NLR), platelet (PLT) and leucocyte between testicular torsion (TT), epididymo-orchitis and healthy controls and further evaluate predictive values of these haematologic parameters in diagnosis and the differential diagnosis of TT. Databases were systematically retrieved, and reference search was also conducted manually. We applied Stata software 12.0 to perform a systematic review and meta-analysis. Ultimately, five case-control studies with 672 participants were recruited for analyses. Pooled analyses indicated that TT patients had lower NLR (WMD = -1.66, 95% CI = -3.25 to -0.06) and PLT (WMD = -27.39, 95% CI = -48.03 to -6.75) compared to epididymo-orchitis patients. In the meantime, TT patients had higher NLR and leucocyte than healthy controls (p < .05). That is to say, when a man develops TT, his NLR and leucocyte will rise up but his NLR will not reach the level of epididymo-orchitis. To sum up, NLR, PLT and leucocyte were vital factors for TT diagnosis. Leucocyte is an useful parameter for diagnosing both TT and epididymo-orchitis, but it cannot be used in differentiating the two diseases. NLR is beneficial parameter for differential diagnosis between TT and epididymo-orchitis. PLT can also be utilised in differential diagnosis among young patients.


Assuntos
Torção do Cordão Espermático/diagnóstico , Epididimite/sangue , Epididimite/diagnóstico , Humanos , Contagem de Linfócitos , Masculino , Volume Plaquetário Médio , Orquite/sangue , Orquite/diagnóstico , Torção do Cordão Espermático/sangue
12.
Sensors (Basel) ; 19(2)2019 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-30669535

RESUMO

Early detection of changes in transient running status from sensor signals attracts increasing attention in modern industries. To achieve this end, this paper presents a new differential equation-based prediction model that can realize one-step-ahead prediction of machine status. Together with this model, an analysis of continuous monitoring of condition signal by means of a null hypothesis testing is presented to inspect/diagnose whether an abnormal status change occurs or not during successive machine operations. The detection operation is executed periodically and continuously, such that the machine running status can be monitored with an online and real-time manner. The effectiveness of the proposed method is demonstrated using three representative real-engineering applications: external loading status monitoring, bearing health status monitoring and speed condition monitoring. The method is also compared with those benchmark methods reported in the literature. From the results, the proposed method demonstrates significant improvements over others, which suggests its superiority and great potentials in real applications.

13.
Pancreatology ; 15(4): 337-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26048200

RESUMO

BACKGROUND AND OBJECTIVES: Chinese herbal drug Da-Cheng-Qi decoction (DCQD) has been widely used for decades to treat acute pancreatitis (AP). Previous trials are mostly designed to state the potential mechanisms of the therapeutic effects rather than to detect its whole effect on metabolism. This study aimed to investigate the efficacy of DCQD on metabolism in AP. METHODS: Twenty-two male adult Sprague-Dawley rats were randomized into three groups. AP was induced by retrograde ductal infusion of 3.5% sodium taurocholate solution in DCQD and AP group, while 0.9% saline solution was used in sham operation (SO) group. Blood samples were obtained 12 h after drug administration and a 600 MHz superconducting Nuclear Magnetic Resonance (NMR) spectrometer was used to detected plasma metabolites. Principal Components Analysis (PCA) and Partial Least Squares-Discriminant Analysis after Orthogonal Signal Correction (OSC-PLS-DA) were applied to analyze the Longitudinal Eddy-delay (LED) and Carr-Purcell-Meiboom-Gill (CPMG) spectra. RESULTS: Differences in concentrations of metabolites among the three groups were detected by OSC-PLS-DA of 1HNMR spectra (both LED and CPMG). Compared with SO group, DCQD group had higher levels of plasma glycerol, glutamic acid, low density lipoprotein (LDL), saturated fatty acid (FA) and lower levels of alanine and glutamine, while the metabolic changes were reversed in the AP group. CONCLUSIONS: Our results demonstrated that DCQD was capable of altering the changed concentrations of metabolites in rats with AP and 1HNMR-based metabolomic approach provided a new methodological cue for systematically investigating the efficacies and mechanisms of DCQD in treating AP.


Assuntos
Medicamentos de Ervas Chinesas/farmacocinética , Medicamentos de Ervas Chinesas/uso terapêutico , Pancreatite/tratamento farmacológico , Pancreatite/metabolismo , Alanina/sangue , Animais , Biotransformação , LDL-Colesterol/sangue , Ácidos Graxos/sangue , Ácido Glutâmico/sangue , Glutamina/sangue , Glicerol/sangue , Espectroscopia de Ressonância Magnética , Masculino , Metabolômica , Ratos , Ratos Sprague-Dawley
14.
Int J Mol Sci ; 16(5): 11678-88, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-26006241

RESUMO

Large-scale genome-wide association studies (GWAS) have revealed that rs10757278 polymorphism (or its proxy rs1333049) on chromosome 9p21 is associated with myocardial infarction (MI) susceptibility in individuals of Caucasian ancestry. Following studies in other populations investigated this association. However, some of these studies reported weak or no significant association. Here, we reevaluated this association using large-scale samples by searching PubMed and Google Scholar databases. Our results showed significant association between rs10757278 polymorphism and MI with p = 6.09 × 10-22, odds ratio (OR) = 1.29, 95% confidence interval (CI) 1.22-1.36 in pooled population. We further performed a subgroup analysis, and found significant association between rs10757278 polymorphism and MI in Asian and Caucasian populations. We identified that the association between rs10757278 polymorphism and MI did not vary substantially by excluding any one study. However, the heterogeneity among the selected studies varies substantially by excluding the study from the Pakistan population. We found even more significant association between rs10757278 polymorphism and MI in pooled population, p = 3.55 × 10-53, after excluding the study from the Pakistan population. In summary, previous studies reported weak or no significant association between rs10757278 polymorphism and MI. Interestingly, our analysis suggests that rs10757278 polymorphism is significantly associated with MI susceptibility by analyzing large-scale samples.


Assuntos
Cromossomos Humanos Par 9/genética , Infarto do Miocárdio/genética , Polimorfismo Genético , Povo Asiático/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , População Branca/genética
15.
Ann Surg ; 259(6): 1201-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24169172

RESUMO

OBJECTIVE: To clarify the roles of organ failure and infection in the outcome of necrotizing pancreatitis. BACKGROUND: Results of previous cohort studies that focused on the roles of infection and organ failure in acute pancreatitis are controversial. METHODS: In this study, we collected the medical records of 447 patients with necrotizing pancreatitis from January 2009 to June 2012. Data associated with organ failure and infection were analyzed. RESULTS: The overall mortality rate was 13% (58/447). Intervention was performed in 223 of 447 patients. Among these 223 patients, 134 were confirmed to be with infected necrosis by a positive culture. The mortality rate was 15% (13/89) in the sterile necrosis group and 18% (24/134) in the infected necrosis group (P = 0.52). A multivariate analysis of death predictors indicated that bacteremia (odds ratio [OR] = 2.76, 95% confidence interval [CI], 1.23-5.46, P < 0.001), age (OR = 1.07, 95% CI, 1.03-1.11, P < 0.001), American Society of Anesthesiologists class (OR = 3.56, 95% CI, 1.65-7.18, P = 0.001), persistent organ failure in the first week (OR = 16.72, 95% CI, 7.04-32.56, P < 0.001), and pancreatic necrosis (OR = 1.73, 95% CI, 1.14-2.98, P = 0.008) were significant factors. CONCLUSIONS: Among patients with necrotizing pancreatitis, the effects of organ failure on mortality are more critical than those of infection. Bacteremia, age, American Society of Anesthesiologists class, persistent organ failure in the first week, and pancreatic necrosis were identified as the predictors of mortality.


Assuntos
Bacteriemia/etiologia , Insuficiência de Múltiplos Órgãos/etiologia , Pancreatite Necrosante Aguda/complicações , Adulto , Idoso , Bacteriemia/diagnóstico , Bacteriemia/epidemiologia , Causas de Morte/tendências , China/epidemiologia , Intervalos de Confiança , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/diagnóstico , Insuficiência de Múltiplos Órgãos/epidemiologia , Razão de Chances , Pancreatite Necrosante Aguda/diagnóstico , Pancreatite Necrosante Aguda/mortalidade , Prognóstico , Estudos Prospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Tomografia Computadorizada por Raios X , Adulto Jovem
16.
Microsyst Nanoeng ; 10: 82, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38915830

RESUMO

[This corrects the article DOI: 10.1038/s41378-022-00478-9.].

17.
J Hazard Mater ; 470: 134237, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38593662

RESUMO

Ti-based MOFs exhibit ultra-high stability in radioactive waste gases containing nitrogen oxides (NOX) and are effective in capturing radioactive iodine. In this study, NH2-MIL-125 was synthesized via a one-pot solvothermal method and its adsorption performance for iodine was investigated using batch adsorption experiments, the stability of materials was tested by simulating post-processing conditions. The results indicated that NH2-MIL-125 had a maximum iodine adsorption capacity of 1.61 g/g at 75 â„ƒ and reached adsorption equilibrium within 60 min, and the adsorption capacity of methyl iodine reached 776.9 mg/g. The material also exhibited excellent stability and iodine adsorption performance in the presence of NOX. After soaking in NO2 for 24 h, its structure remained stable and the adsorption capacity for iodine remained at 231.5 mg/g. The excellent co-adsorption performance of NH2-MIL-125 on iodine and NOX was attributed to the synergistic effects of Ti-OH groups and amino functional groups. These findings provide a reference for the capture of radioactive iodine and also demonstrate the potential of NH2-MIL-125 for iodine capture during spent fuel reprocessing.

18.
Micromachines (Basel) ; 15(4)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38675327

RESUMO

Electro-optic modulation devices are essential components in the field of integrated optical chips. High-speed, low-loss electro-optic modulation devices represent a key focus for future developments in integrated optical chip technology, and they have seen significant advancements in both commercial and laboratory settings in recent years. Current electro-optic modulation devices typically employ architectures based on thin-film lithium niobate (TFLN), traveling-wave electrodes, and impedance-matching layers, which still suffer from transmission losses and overall design limitations. In this paper, we demonstrate a lithium niobate electro-optic modulation device based on bound states in the continuum, featuring a non-overlay structure. This device exhibits a transmission loss of approximately 1.3 dB/cm, a modulation bandwidth of up to 9.2 GHz, and a minimum half-wave voltage of only 3.3 V.

19.
Sci Total Environ ; 924: 171636, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38485021

RESUMO

Struvite (MgNH4PO4·6H2O, Magnesium ammonium phosphate, MAP), recovered from wastewater, has potential application as a slow-release fertilizer. However, crystal size distribution (CSD) of recovered MAP typically lied in the range of 50-300 µm, due to fast nucleation rate and notably narrow metastable zone width (MSZW) of MAP, with purity levels 40-90 %. In order to control the rate of nucleation, a novel magnesium source with the form of MgHPO4·3H2O wrapped with Mg(OH)2 was prepared, referred to as P-3. This compound gradually released Mg2+ and PO43-, regulating solution concentration kept in MSZW to promote crystal growth. The inherent Mg(OH)2 within P-3 also acted as a pH regulator in wastewater, eliminating the necessity for additional acid or alkali adjustments during crystallization process. The MAP precipitated by P-3 exhibited an impressive CSD of 5000-7000 µm, with a maximum size reaching 10,000 µm. This represented the largest CSD reported in literature for recovered MAP from wastewater. The significance of the ultra-large MAP precipitated by P-3 lied in its enhanced resistance to impurity adsorption, resulting in MAP with a remarkable purity 97 %, under conditions of low heavy metal ion concentration approximately 5 mg/L. Furthermore, the removal efficiency of ammonia nitrogen (NH4+) can reach 92 %. In comparison, two other magnesium sources, soluble salts (MgCl2 and Na2HPO4, P-1) and a combination of insoluble salts (Mg(OH)2 and MgHPO4, P-2) were evaluated alongside P-3. The CSD of MAP precipitated from P-1, P-2 was both <100 µm, with purity levels of 90 and 92 % and NH4+ removal efficiency of 92 and 90 %, respectively. Importantly, the strategy of obtaining ultra-large size MAP from wastewater in this study provided novel insights into the crystallization of other insoluble salts with large sizes.

20.
Environ Pollut ; 357: 124442, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38944180

RESUMO

The extraction of 99TcO4- from radioactive effluents is extremely crucial for the purposes of nuclear disposal and environmental remediation. Herein, utilizing a facile and low-cost synthesis method, we report a pyridinium-based cationic polymer network, CPP-Cl, with impressive adsorption performance and ultrafast adsorption kinetics towards ReO4-. The structure featuring highly density of charged pyridinium units was synthesized, making it an effective adsorbent for capturing ReO4-. The material showed fast ReO4- adsorption kinetics reaching adsorption equilibrium within 30 s, an excellent capture capability of 1069.7 mg/g, and exceptional separation efficiency of 94.3% for removing 1000 ppm ReO4-. Furthermore, it possessed excellent reusability in multiple sorption/desorption trials and good uptake capacity within a widely ranging pH values. It is noteworthy that the extraction efficiency of CPP-Cl for ReO4- from simulated nuclear waste can be up to 94.2%. The favorable performance of the material in multiple tests revealed that CPP-Cl has tremendous potential as a high-efficiency sorbent for capturing 99TcO4-/ReO4- in complex nuclear associated environmental systems.

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