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1.
Environ Sci Technol ; 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-39088742

ABSTRACT

A series of Mn and Fe metal oxide catalysts loaded onto USY, as well as single metal oxides, were prepared and characterized. The effects of interactions between the catalytic components and the introduction of gas phase NO on the catalytic ozonation of toluene were investigated. Characterization showed that there existed strong interactions between MnOx, FeOx, and USY, which enhanced the content of oxygen vacancies and acid sites of the catalysts and thus boosted the generation of reactive oxygen species and the adsorption of toluene. The MnFeOx-USY catalyst with MnOx and FeOx dimetallic oxides exhibited the most excellent performance of catalytic ozonation of toluene. On the other hand, the presence of NOx in reaction gas mixtures significantly promoted both toluene conversion and mineralization, which was attributed to the formation of nitrate species on the catalysts surface and thus the increase of both acid sites and toluene oxidation sites. Meanwhile, the reaction mechanism between O3 and C7H8 was modified in which the strong interactions between MnOx, FeOx, and USY accelerated the reaction progress based on the L-H route. In addition, the formation of the surface nitrate species not only promoted reaction progress following the L-H route but also resulted in the occurrence of the reaction via the E-R route.

2.
Environ Sci Technol ; 58(27): 12091-12100, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38916160

ABSTRACT

The widespread ozone (O3) pollution is extremely hazardous to human health and ecosystems. Catalytic decomposition into O2 is the most promising method to eliminate ambient O3, while the fast deactivation of catalysts under humid conditions remains the primary challenge for their application. Herein, we elaborately developed a splendidly active and stable Mn-based catalyst with double hydrophobic protection of active carbon (AC) and CeO2 (CeMn@AC), which possessed abundant interfacial oxygen vacancies and excellent desorption of peroxide intermediates (O22-). Under extremely humid (RH = 90%) conditions and a high space velocity of 1200 L h-1 g-1, the optimized CeMn@AC achieved nearly 100% O3 conversion (140 h) at 5 ppm, showing unprecedented catalytic activity and moisture resistance toward O3 decomposition. In situ DRIFTS and theory calculations confirmed that the exceptional moisture resistance of CeMn@AC was ascribed to the double protection effect of AC and CeO2, which cooperatively prevented the competitive adsorption of H2O molecules and their accumulation on the active sites of MnO2. AC provided a hydrophobic reaction environment, and CeO2 further alleviated moisture deterioration of the MnO2 particles exposed on the catalyst surface via the moisture-resistant oxygen vacancies of MnO2-CeO2 crystal boundaries. This work offers a simple and efficient strategy for designing moisture-resistant materials and facilitates the practical application of the O3 decomposition catalysts in various environments.


Subject(s)
Ozone , Ozone/chemistry , Catalysis , Carbon/chemistry , Manganese Compounds/chemistry , Cerium/chemistry , Oxides/chemistry
3.
Environ Sci Technol ; 57(48): 20053-20063, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-37936384

ABSTRACT

Modulating oxygen vacancies of catalysts through crystal facet engineering is an innovative strategy for boosting the activity for ozonation of catalytic volatile organic compounds (VOCs). In this work, three kinds of facet-engineered monoclinic NiO catalysts were successfully prepared and utilized for catalytic toluene ozonation (CTO). Density functional theory calculations revealed that Ni vacancies were more likely to form preferentially than O vacancies on the (110), (100), and (111) facets of monoclinic NiO due to the stronger Ni-vacancy formation ability, further affecting O-vacancy formation. Extensive characterizations demonstrated that Ni vacancies significantly promoted the formation of O vacancies and thus reactive oxygen species in the (111) facet of monoclinic NiO, among the three facets. The performance evaluation showed that the monoclinic NiO catalyst with a dominant (111) facet exhibits excellent performance for CTO, achieving a toluene conversion of ∼100% at 30 °C after reaction for 120 min under 30 ppm toluene, 210 ppm ozone, 45% relative humidity, and a space velocity of 120 000 h-1. This outperformed the previously reported noble/non-noble metal oxide catalysts used for CTO at room temperature. This study provided novel insight into the development of highly efficient facet-engineered catalysts for the elimination of catalytic VOCs.


Subject(s)
Ozone , Volatile Organic Compounds , Toluene/chemistry , Oxides , Oxygen , Catalysis
4.
Mol Biol Rep ; 50(4): 3515-3523, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36787051

ABSTRACT

BACKGROUND: There are several investigations that have revealed that cerebral dopamine (DA) plays a pivotal role in the occurrence of premature ejaculation (PE). Although tyrosine hydroxylase (TH) is an essential enzyme for the synthesis of DA, only few investigations have described the role of TH in regulation mechanisms for ejaculation till now. To investigate whether there is a correlation between TH expression level in the brain and different ejaculation behavior in rats. Then explore whether the TH expression in the brain will change after acute dapoxetine treatment in rats with Rapid ejaculation. METHODS AND RESULTS: Rats (male, S-D rats, 6-8 weeks) were separated into three groups based on their ejaculation frequency: Rapid, Normal, and Sluggish. Expression level of DA in the brain was determined by enzyme-linked immune sorbent assay (ELISA) kit, TH expression level in the brain was determined by immunohistochemistry and Western Blot (WB) techniques. Among the three groups, DA and TH expression level were the highest in the Rapid ejaculation group, while the lowest was the Sluggish ejaculation group. The results also showed that TH level was positively associated with ejaculation frequency (r = 0.8038, P < 0.001) and negatively associated with ejaculation latency (r=-0.6199, P = 0.018). Furthermore, acute dapoxetine therapy in rats with Rapid ejaculation downregulated TH level in the brain. CONCLUSION: Changes in ejaculation behavior were significantly linked with TH level. Upregulated TH in selected brain regions related with ejaculation could cause rapid ejaculation. The effect of dapoxetine in prolonging ejaculation could be related to TH downregulation within the brain.


Subject(s)
Premature Ejaculation , Humans , Male , Rats , Animals , Premature Ejaculation/drug therapy , Tyrosine 3-Monooxygenase , Treatment Outcome , Selective Serotonin Reuptake Inhibitors
5.
Angew Chem Int Ed Engl ; 62(43): e202313099, 2023 Oct 23.
Article in English | MEDLINE | ID: mdl-37694769

ABSTRACT

The development of practical materials for (de)hydrogenation reactions is a prerequisite for the launch of a sustainable hydrogen economy. Herein, we present the design and construction of an atomically dispersed dual-metal site Co/Cu-N-C catalyst allowing significantly improved dehydrogenation of formic acid, which is available from carbon dioxide and green hydrogen. The active catalyst centers consist of specific CoCuN6 moieties with double-N-bridged adjacent metal-N4 clusters decorated on a nitrogen-doped carbon support. At optimal conditions the dehydrogenation performance of the nanostructured material (mass activity 77.7 L ⋅ gmetal -1 ⋅ h-1 ) is up to 40 times higher compared to commercial 5 % Pd/C. In situ spectroscopic and kinetic isotope effect experiments indicate that Co/Cu-N-C promoted formic acid dehydrogenation follows the so-called formate pathway with the C-H dissociation of HCOO* as the rate-determining step. Theoretical calculations reveal that Cu in the CoCuN6 moiety synergistically contributes to the adsorption of intermediate HCOO* and raises the d-band center of Co to favor HCOO* activation and thereby lower the reaction energy barrier.

6.
Environ Sci Technol ; 56(17): 12625-12634, 2022 09 06.
Article in English | MEDLINE | ID: mdl-35947769

ABSTRACT

Regeneration of spent V2O5-WO3/TiO2 catalysts is highly desirable, especially for those containing hypertoxic As, which is categorized as hazardous waste. However, common solution-leaching methods suffer from the trade-off between As removal and V2O5 retention, and it would be necessary to introduce extra proceedings like ingredients reimplantation and As-bearing waste treatment after regeneration. Herein, a formic acid-mediated regeneration strategy has been developed to achieve superior catalytic activity, short timescale regeneration, and nontoxic metallic As recycling with controllable and safe conduction. The specific activity of the optimal regenerated catalyst reaches 98.3% of the fresh catalyst with 99.1% As removal and less than 1.8% V loss within 15 min. Structure characterizations reveal that the distorted VOx molecular structure, surface acidity, and redox property recover to the fresh level after regeneration. In situ investigation of the regeneration process indicates that As-OH removal together with V-OH generation occurs at the first regeneration stage, followed by the active center V═O sites over-reduction at the second stage. The retained V═O species by suitable regeneration temperature and time are essential for NH3-selective catalytic reduction (SCR) since As existence and VOx over-reduction will separately cause unstable and excessive NH3 adsorption to further suppress the reaction cycle. The developed strategy and improved understanding of active site protection would exert benefits on the development of efficient and time-saving regeneration methods for spent catalysts.


Subject(s)
Poisons , Ammonia/chemistry , Catalysis , Formates , Titanium/chemistry
7.
Environ Sci Technol ; 56(22): 15695-15704, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-36259958

ABSTRACT

Mn-based catalysts hold the promise of practical applications in catalytic ozonation of toluene at room temperature, yet improvement of toluene conversion and COx selectivity remains challenging. Here, an innovative α-MnO2/ZSM-5 catalyst modified with SO42- was successfully prepared, and both characterizations and density functional theory (DFT) calculations showed that SO42- introduction facilitated the formation of oxygen vacancies, Lewis and Brönsted acid sites, and active oxygen species and enhanced the adsorption ability of toluene on α-MnO2/ZSM-5. Characterizations also showed that SO42- introduction made the catalyst possess larger specific surface area, superior reducibility, and stronger surface acidity. As a result, α-MnO2/ZSM-5 with a S/Mn molar ratio of 0.019 exhibited the best toluene conversion and COx selectivity, 87 and 94%, respectively, after the reaction for 8 h at 30 °C under an initial concentration of 5 ppm toluene and 45 ppm ozone, relative humidity of 45%, and space velocity of 32,000 h-1, far superior to those of non-noble catalysts reported to date under comparable reaction conditions. The synergistic role of increased oxygen vacancies and acid sites of α-MnO2/ZSM-5 modified with SO42- resulted in excellent toluene conversion and COx selectivity. The findings represented a critical step toward the rational design and synthesis of highly efficient catalysts for catalytic ozonation of toluene.

8.
Environ Sci Technol ; 56(10): 6282-6293, 2022 05 17.
Article in English | MEDLINE | ID: mdl-35512288

ABSTRACT

Microorganisms residing in the human respiratory tract can be exhaled, and they constitute a part of environmental microbiotas. However, the expiratory microbiota community and its associations with environmental microbiotas remain poorly understood. Here, expiratory bacteria and fungi and the corresponding microbiotas from the living environments were characterized by DNA amplicon sequencing of residents' exhaled breath condensate (EBC) and environmental samples collected from 14 residences in Nanjing, China. The microbiotas of EBC samples, with a substantial heterogeneity, were found to be as diverse as those of skin, floor dust, and airborne microbiotas. Model fitting results demonstrated the role of stochastic processes in the assembly of the expiratory microbiota. Using a fast expectation-maximization algorithm, microbial community analysis revealed that expiratory microbiotas were differentially associated with other types of microbiotas in a type-dependent and residence-specific manner. Importantly, the expiratory bacteria showed a composition similarity with airborne bacteria in the bathroom and kitchen environments with an average of 12.60%, while the expiratory fungi showed a 53.99% composition similarity with the floor dust fungi. These differential patterns indicate different relationships between expiratory microbiotas and the airborne microbiotas and floor dust microbiotas. The results here illustrated for the first time the associations between expiratory microbiotas and indoor microbiotas, showing a potential microbial exchange between the respiratory tract and indoor environment. Thus, improved hygiene and ventilation practices can be implemented to optimize the indoor microbial exposome, especially in indoor bathrooms and kitchens.


Subject(s)
Air Pollution, Indoor , Microbiota , Air Pollution, Indoor/analysis , Bacteria/genetics , Dust/analysis , Fungi , Humans , Ventilation
9.
J Sex Med ; 18(1): 72-82, 2021 01.
Article in English | MEDLINE | ID: mdl-33339761

ABSTRACT

BACKGROUND: Although temperament-character traits and attitudes toward premature ejaculation (PE) are known to be associated with PE, it is of great significance to study them in PE. Moreover, few studies have evaluated these traits and attitudes in the new classification of 4 subtypes of PE. AIM: We investigated the temperament-character traits and attitudes toward PE in 4 types of PE and their associations with PE. METHODS: Between December 2018 and December 2019, we conducted a survey in our hospital, and enrolled 350 men who complained of PE and 252 men without any complaint of PE. Temperament-character traits and attitudes toward PE were independently assessed by the Temperament and Character Inventory-Revised and several targeted questions, respectively. The Index of Premature Ejaculation (IPE) was used to evaluate ejaculation control, sexual life satisfaction, and distress caused by PE. OUTCOMES: The outcomes included differences of temperament-character traits and attitudes toward PE among 2 groups and their associations with PE. RESULTS: Of the 2 groups, men with PE complaints had lower novelty seeking/self-transcendence (NS/ST) scores and higher harm avoidance (HA) scores vs men without any complaints of PE. Among the 4 types of PE, men with variable PE had the highest score of HA and lowest score of NS; the lowest score of ST was recorded in men with lifelong PE. Additionally, the total and subdomain scores of IPE in men with subjective PE were higher than the other subtypes of PE. After adjusting for age, positive correlations were observed in HA score and total and subdomain scores of IPE, whereas the inverse was true corresponding to NS and ST. CLINICAL IMPLICATIONS: The current study has provided a new perspective for understanding the impact of psychological factors on PE. STRENGTHS & LIMITATIONS: This is the first study to systematically assess the effects of personality traits and attitudes on PE, especially among the 4 types of PE. The main drawback is that the generalizability of this study may be limited by the fact that it was conducted in a single cultural/societal background. CONCLUSION: Men who complained of PE tended to react with indifference or rejection to novelty, tended to feel unsatisfied, cannot effectively adapt to changes in the surrounding environment, and tended to avoid situations involving risk. These characteristics could lead to their becoming disheartened when faced with PE. Furthermore, the attitude of men with PE reflects the needs of the patient during treatment from one aspect. Gao P, Gao J Wang Y, et al. Temperament-Character Traits and Attitudes Toward Premature Ejaculation in 4 Types of Premature Ejaculation. J Sex Med 2021;18:72-82.


Subject(s)
Premature Ejaculation , Attitude , Character , Ejaculation , Humans , Male , Temperament
10.
Environ Sci Technol ; 54(22): 14740-14749, 2020 11 17.
Article in English | MEDLINE | ID: mdl-33151663

ABSTRACT

The deactivation of selective catalytic reduction (SCR) catalysts by arsenic is a serious problem for NH3-SCR. However, it is tough to design catalysts with good resistance to arsenic compared to other poisons such as alkali metal, SO2, etc., because As not only deteriorates surface acidity but also redox property, causing excessive N2O generation. A novel CeO2-WO3-Al2O3 catalyst is developed with excellent arsenic resistance in this study, which presents only less than 10% activity loss compared to nearly 40% loss for CeO2-WO3 with same arsenic loading (As: 2.1 wt %). Moreover, a significant negative impact on the N2O generation for poisoning catalysts from 26.7 to 7.5 ppm has also been found. The characterization results demonstrated that the interaction between cerium and arsenic lead to Lewis acid sites and oxygen vacancies loss as well as unexpected oxidation sites formation. However, the introduction of Al weakens the deactivation effect by replacing cerium to interact with arsenic. Three aspects are proposed for obtaining excellent arsenic-resistant performance: (1) the protection of Lewis acid sites, (2) release of oxygen vacancies from As restriction, and (3) confinement of As5+ oxidizing capacity. This study may provide an effective strategy to design and develop novel virtuous antipoisoning catalysts.


Subject(s)
Arsenic , Cerium , Aluminum Oxide , Ammonia , Catalysis , Oxidation-Reduction , Tungsten
11.
Mol Biol Rep ; 47(5): 3605-3613, 2020 May.
Article in English | MEDLINE | ID: mdl-32347420

ABSTRACT

This study is to explore the relationship between vascular endothelial growth factor (VEGF) and pathological changes in cryptorchidism by using murine model of intraperitoneal cryptorchidism with surgical operation. To investigate the relationship between the changes of VEGF expression and heat stress inducing germ cell damage in testicular tissue. Six-week-old ICR male mice were operated to make unilateral cryptorchidism mouse model. Here in our study, a remarkable damaged of germ cells are seen in murine model of unilateral cryptorchidism. And the expression of VEGF was significantly changed in a time dependent way and consistent with the pathological changes of testis, this leading us to conclude that there was a negative correlation between VEGF levels and germ cell damage in unilateral cryptorchidism mouse model. We propose that there is a time dependent decrease of VEGF expression in cryptorchidism and confirm that VEGF is essential in spermatogenesis disorder caused by cryptorchidism and non-obstructive azoospermia.


Subject(s)
Cryptorchidism/pathology , Spermatogenesis/physiology , Vascular Endothelial Growth Factor A/metabolism , Animals , Apoptosis , Cryptorchidism/metabolism , Cryptorchidism/surgery , Disease Models, Animal , Germ Cells/metabolism , Male , Mice , Mice, Inbred ICR , Testis/metabolism
12.
Environ Sci Technol ; 53(22): 13332-13343, 2019 Nov 19.
Article in English | MEDLINE | ID: mdl-31642660

ABSTRACT

A series of Na-OMS-2 catalysts was prepared by a facile solid-state reaction method. Their physiochemical properties were characterized, and the catalytic activity for ozone decomposition was evaluated. The results showed that the introduction of Na+ in the tunnel framework of OMS-2 facilitated lattice defect formation, which significantly enhanced oxygen vacancies, which are believed to be the active sites for ozone decomposition. Density functional theory calculations also showed that both the oxygen vacancy formation energy and ozone adsorption energy over Na-OMS-2 decreased because of Na+ introduction. Sodium ion introduction significantly improved the OMS-2 catalytic activity for ozone decomposition. The Na-OMS-2 catalyst with a Na/Mn molar ratio of 1/4 exhibited ozone conversion at 92.5% at 25 ± 1 °C after reaction for 6 h under an initial ozone concentration of 45 ± 2 ppm, a relative humidity of 30 ± 2%, and a space velocity of 660 000 h-1. This showed that this catalyst was far superior to manganese oxide catalysts reported to date. Furthermore, the research results also showed that the catalytic activity of Na-OMS-2 deactivated by the accumulation of oxygen-related intermediates was recovered by calcination at 425 °C under N2 atmosphere for 0.5 h. Finally, a complete mechanism for ozone decomposition, catalyst deactivation, and regeneration was proposed.


Subject(s)
Ozone , Adsorption , Catalysis , Oxygen , Sodium
13.
Environ Sci Technol ; 52(15): 8578-8587, 2018 08 07.
Article in English | MEDLINE | ID: mdl-29925229

ABSTRACT

An extraordinary deactivation offset effect of calcium and arsenic on CeO2-WO3 catalyst had been found for selective catalytic reduction of NO with NH3 (NH3-SCR). It was discovered that the maximum NO x conversion of As-Ca poisoned catalyst reached up to 89% at 350 °C with the gaseous hourly space velocity of 120 000 mL·(g·h)-1. The offset effect mechanisms were explored with respect to the changes of catalyst structure, surface acidity, redox property and reaction route by XRD, XPS, H2-TPR, O2-TPD, NH3-TPD and in situ Raman, in situ TG, and DRIFTS. The results manifested that Lewis acid sites and reducibility originating from CeO2 were obviously recovered, because the strong interaction between cerium and arsenic was weakened when Ca and As coexisted. Meanwhile, the CaWO4 phase generated on Ca poisoned catalyst almost disappeared after As doping together, which made for Brønsted acid sites reformation on catalyst surface. Furthermore, surface Ce4+ proportion and oxygen defect sites amount were also restored for two-component poisoned catalyst, which favored NH3 activation and further reaction. Finally, the reasons for the gap of catalytic performance between fresh and As-Ca poisoned catalyst were also proposed as follows: (1) surface area decrease; (2) crystalline WO3 particles generation; and (3) oxygen defect sites irreversible loss.


Subject(s)
Arsenic , Cerium , Ammonia , Calcium , Catalysis
14.
J Environ Sci (China) ; 66: 94-103, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29628112

ABSTRACT

Effects of carrier gas composition (N2/air) on NH3 production, energy efficiency regarding NH3 production and byproducts formation from plasma-catalytic decomposition of urea were systematically investigated using an Al2O3-packed dielectric barrier discharge (DBD) reactor at room temperature. Results show that the presence of O2 in the carrier gas accelerates the conversion of urea but leads to less generation of NH3. The final yield of NH3 in the gas phase decreased from 70.5%, 78.7%, 66.6% and 67.2% to 54.1%, 51.7%, 49.6% and 53.4% for applied voltages of 17, 19, 21 and 23kV, respectively when air was used as the carrier gas instead of N2. From the viewpoint of energy savings, however, air carrier gas is better than N2 due to reduced energy consumption and increased energy efficiency for decomposition of a fixed amount of urea. Carrier gas composition has little influence on the major decomposition pathways of urea under the synergetic effects of plasma and Al2O3 catalyst to give NH3 and CO2 as the main products. Compared to a small amount of N2O formed with N2 as the carrier gas, however, more byproducts including N2O and NO2 in the gas phase and NH4NO3 in solid deposits were produced with air as the carrier gas, probably due to the unproductive consumption of NH3, the possible intermediate HNCO and even urea by the abundant active oxygen species and nitrogen oxides generated in air-DBD plasma.


Subject(s)
Air Pollutants/chemistry , Ammonia/chemistry , Urea/chemistry , Catalysis , Models, Chemical , Nitrogen Oxides
15.
Molecules ; 22(3)2017 Feb 27.
Article in English | MEDLINE | ID: mdl-28264456

ABSTRACT

A series of nanostructured Pt-Au/MOx-CeO2 (M = Mn, Fe, Ti) catalysts were prepared and their catalytic performance for the co-oxidation of carbon monoxide (CO) and hydrogen (H2) were evaluated at room temperature. The results showed that MOx promoted the CO oxidation of Pt-Au/CeO2, but only the TiO2 could enhance co-oxidation of CO and H2 over Pt-Au/CeO2. Related characterizations were conducted to clarify the promoting effect of MOx. Temperature-programmed reduction of hydrogen (H2-TPR) and X-ray photoelectron spectroscopy (XPS) results suggested that MOx could improve the charge transfer from Au sites to CeO2, resulting in a high concentration of Ce3+ and cationic Au species which benefits for the CO oxidation. In-situ diffuse reflectance infrared Fourier transform spectroscopy (In-situ DRIFTS) results indicated that TiO2 could facilitate the oxidation of H2 over the Pt-Au/TiO2-CeO2 catalyst.


Subject(s)
Carbon Monoxide/chemistry , Gold/chemistry , Hydrogen/chemistry , Oxides/chemistry , Platinum/chemistry , Catalysis , Cerium/chemistry , Ferric Compounds/chemistry , Manganese Compounds/chemistry , Nanostructures/chemistry , Oxidation-Reduction , Temperature , Titanium/chemistry
16.
Molecules ; 21(11)2016 Nov 14.
Article in English | MEDLINE | ID: mdl-27854237

ABSTRACT

A series of MnOx-CeO2 and MnOx-TiO2 catalysts were prepared by a homogeneous precipitation method and their catalytic activities for the NO oxidation in the absence or presence of SO2 were evaluated. Results show that the optimal molar ratio of Mn/Ce and Mn/Ti are 0.7 and 0.5, respectively. The MnOx-CeO2 catalyst exhibits higher catalytic activity and better resistance to SO2 poisoning than the MnOx-TiO2 catalyst. On the basis of Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), and scanning transmission electron microscope with mapping (STEM-mapping) analyses, it is seen that the MnOx-CeO2 catalyst possesses higher BET surface area and better dispersion of MnOx over the catalyst than MnOx-TiO2 catalyst. X-ray photoelectron spectroscopy (XPS) measurements reveal that MnOx-CeO2 catalyst provides the abundance of Mn3+ and more surface adsorbed oxygen, and SO2 might be preferentially adsorbed to the surface of CeO2 to form sulfate species, which provides a protection of MnOx active sites from being poisoned. In contrast, MnOx active sites over the MnOx-TiO2 catalyst are easily and quickly sulfated, leading to rapid deactivation of the catalyst for NO oxidation. Furthermore, temperature programmed desorption with NO and O2 (NO + O2-TPD) and in situ diffuse reflectance infrared transform spectroscopy (in situ DRIFTS) characterizations results show that the MnOx-CeO2 catalyst displays much stronger ability to adsorb NOx than the MnOx-TiO2 catalyst, especially after SO2 poisoning.


Subject(s)
Cerium/chemistry , Manganese Compounds/chemistry , Nitric Oxide/chemistry , Oxides/chemistry , Titanium/chemistry , Adsorption , Catalysis , Oxidation-Reduction , Photoelectron Spectroscopy , Surface Properties , Temperature , X-Ray Diffraction
17.
World J Mens Health ; 2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38311371

ABSTRACT

PURPOSE: Explore the causal relationship between the gut microbiota and erectile dysfunction (ED) at phylum, class, order, family, and genus levels, and identify specific pathogenic bacteria that may be associated with the onset and progression of ED. MATERIALS AND METHODS: The genetic variation data of 196 human gut microbiota incorporated in our study came from the human gut microbiome Genome Wide Association Studies (GWAS) dataset released by the MiBioGen Consortium. The GWAS statistics for ED were extracted from one study by Bovijn et al., which included 223,805 participants of European ancestry, of whom 6,175 were diagnosed with ED. Subsequently, Mendelian randomization (MR) analysis was carried out to explore whether a causal relationship exists between the gut microbiota and ED. Additionally, bidirectional MR analysis was performed to examine the directionality of the causal relationship. RESULTS: Through MR analysis, we found that family Lachnospiraceae (odds ratio [OR]: 1.27, 95% confidence interval [CI]: 1.05-1.52, p=0.01) and its subclass genus LachnospiraceaeNC2004 group (OR: 1.17, 95% CI: 1.01-1.37, p=0.04) are associated with a higher risk of ED. In addition, genus Oscillibacter (OR: 1.17, 95% CI: 1.02-1.35, p=0.03), genus Senegalimassilia (OR: 1.32, 95% CI: 1.06-1.64, p=0.01) and genus Tyzzerella3 (OR: 1.14, 95% CI: 1.02-1.27, p=0.02) also increase the risk of ED. In contrast, the inverse variance weighted estimate of genus RuminococcaceaeUCG013 (OR: 0.77, 95% CI: 0.61-0.96, p=0.02) suggests that it has a protective effect against the occurrence of ED. CONCLUSIONS: This study preliminarily identified 6 bacterial taxa that may have a causal relationship with ED, including family Lachnospiraceae, genus Lachnospiraceae NC2004 group, Oscillibacter, Senegalimassilia, Tyzzerella 3 and Ruminococcaceae UCG013. These identified important bacterial taxa may serve as candidates for microbiome intervention in future ED clinical trials.

18.
Nat Commun ; 15(1): 3592, 2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38678057

ABSTRACT

Supported nanoclusters (SNCs) with distinct geometric and electronic structures have garnered significant attention in the field of heterogeneous catalysis. However, their directed synthesis remains a challenge due to limited efficient approaches. This study presents a plasma-assisted treatment strategy to achieve supported metal oxide nanoclusters from a rapid transformation of monomeric dispersed metal oxides. As a case study, oligomeric vanadia-dominated surface sites were derived from the classic supported V2O5-WO3/TiO2 (VWT) catalyst and showed nearly an order of magnitude increase in turnover frequency (TOF) value via an H2-plasma treatment for selective catalytic reduction of NO with NH3. Such oligomeric surface VOx sites were not only successfully observed and firstly distinguished from WOx and TiO2 by advanced electron microscopy, but also facilitated the generation of surface amide and nitrates intermediates that enable barrier-less steps in the SCR reaction as observed by modulation excitation spectroscopy technologies and predicted DFT calculations.

19.
Andrology ; 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38436126

ABSTRACT

BACKGROUND: Since the outbreak of coronavirus disease 2019, it has had a serious impact on people's physical and mental health. However, in our clinical work, we have found that the erectile function of coronavirus disease 2019 patients with neurological decline was often seriously affected. OBJECTIVES: To further explore the relationship between erectile dysfunction and neurological dysfunction caused by coronavirus disease 2019. MATERIALS AND METHODS: We conducted a survey from August 2022 to February 2023 at the First Affiliated Hospital of Anhui Medical University and the Third People's Hospital of Linyi City. A total of 251 subjects with a history of coronavirus disease 2019 infection were included. Symptoms and changes in erectile function after the coronavirus disease 2019 infection were collected and assessed using the International Index of Erectile Function-5 scale and several targeted questions. RESULTS: In this study, we found that in patients infected with novel coronavirus, the proportion of erectile dysfunction was higher in those with neurological manifestations such as olfactory and taste impairment or psychological symptoms such as anxiety. DISCUSSION: We found that neurological decline and psychological factors were independent and significant risk factors for erectile dysfunction caused by coronavirus disease 2019. CONCLUSION: Patients with neurological damage or psychiatric symptoms are more likely to have erectile dysfunction, suggesting that the 2019 novel coronavirus may affect erectile function by damaging nerves. This provides a new insight into the mechanism of erectile dysfunction.

20.
J Environ Sci (China) ; 25(1): 213-9, 2013 Jan 01.
Article in English | MEDLINE | ID: mdl-23586317

ABSTRACT

A group parameter approach using "total organic halogen" is effective for monitoring gaseous organic halogen compounds, including fluorine, chlorine, and bromine compounds, generated from combustion. We described the use of barrier-discharge radiofrequency-helium-plasma/atomic emission spectrometry, for the detection of semi- and low-volatile organic halogen compounds (SLVOXs), which can be collected by Carbotrap adsorbents and analyzed using thermal desorption. The optimal carrier gas flow rates at the injection and desorption lines were established to be 100 mL/min. The detection range for SLVOXs in the gaseous samples was from 10 ng to tens of micrograms. Measuring F was more difficult than measuring C1 or Br, because the wavelength of F is close to that of air. The barrier-discharge radiofrequency-helium-plasma/atomic emission spectrometry measured from 85% to 103% of the SLVOXs in the gas sample. It has been found that Carbotrap B is appropriate for high-boiling-point compounds, and Carbotrap C is suitable for the determination of organic halogen compounds with lower boiling points, in the range 200-2300C. Under optimal analysis conditions, a chlorine-containing plastic was destroyed using different oxygen concentrations. Lower oxygen concentrations resulted in the production of lower amounts of organic halogen compounds.


Subject(s)
Halogens/analysis , Volatile Organic Compounds/analysis , Oxygen/chemistry
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