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1.
BMC Infect Dis ; 24(1): 420, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38644476

ABSTRACT

BACKGROUND: This cross-sectional study investigates infection prevention and control (IPC) competencies among healthcare professionals in northwest China, examining the influence of demographic factors, job titles, education, work experience, and hospital levels. METHODS: Data from 874 respondents across 47 hospitals were collected through surveys assessing 16 major IPC domains. Statistical analyses, including Mann-Whitney tests, were employed to compare competencies across variables. RESULTS: Significant differences were identified based on gender, job titles, education, work experience, and hospital levels. Females demonstrated higher IPC competencies, while senior positions exhibited superior performance. Higher educational attainment and prolonged work experience positively correlated with enhanced competencies. Variances across hospital levels underscored context-specific competencies. CONCLUSION: Demographic factors and professional variables significantly shape IPC competencies. Tailored training, considering gender differences and job roles, is crucial. Higher education and prolonged work experience positively impact proficiency. Context-specific interventions are essential for diverse hospital settings, informing strategies to enhance IPC skills and mitigate healthcare-associated infections effectively.


Subject(s)
Health Personnel , Humans , Cross-Sectional Studies , China , Female , Male , Health Personnel/statistics & numerical data , Adult , Middle Aged , Infection Control/methods , Surveys and Questionnaires , Cross Infection/prevention & control , Clinical Competence/statistics & numerical data , Hospitals
2.
Angew Chem Int Ed Engl ; 63(9): e202313858, 2024 Feb 26.
Article in English | MEDLINE | ID: mdl-38185801

ABSTRACT

Catalysts involving post-transition metals have shown almost invincible performance on generating formate in electrochemical CO2 reduction reaction (CO2 RR). Conversely, Cu without post-transition metals has struggled to achieve comparable activity. In this study, a sulfur (S)-doped-copper (Cu)-based catalyst is developed, exhibiting excellent performance in formate generation with a maximum Faradaic efficiency of 92 % and a partial current density of 321 mA cm-2 . Ex situ structural elucidations reveal the presence of abundant grain boundaries and high retention of S-S bonds from the covellite phase during CO2 RR. Furthermore, thermodynamic calculations demonstrate that S-S bonds can moderate the binding energies with various intermediates, further improving the activity of the formate pathway. This work is significant in modifying a low-cost catalyst (Cu) with a non-metallic element (S) to achieve comparable performance to mainstream catalysts for formate generation in industrial grade.

3.
Angew Chem Int Ed Engl ; 63(5): e202314384, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38100253

ABSTRACT

Photocatalytic CO2 reduction into ideal hydrocarbon fuels, such as CH4 , is a sluggish kinetic process involving adsorption of multiple intermediates and multi-electron steps. Achieving high CH4 activity and selectivity therefore remains a great challenge, which largely depends on the efficiency of photogenerated charge separation and transfer as well as the intermediate energy levels in CO2 reduction. Herein, we construct La and Cu dual-atom anchored carbon nitride (LaCu/CN), with La-N4 and Cu-N3 coordination bonds connected by Cu-N-La bridges. The asymmetric Cu-N-La species enables the establishment of an atomic-level donor-acceptor structure, which allows the migration of electrons from La atoms to the reactive Cu atom sites. Simultaneously, intermediates during CO2 reduction on LaCu/CN demonstrate thermodynamically more favorable process for CH4 formation based on theoretical calculations. Eventually, LaCu/CN exhibits a high selectivity (91.6 %) for CH4 formation with a yield of 125.8 µmol g-1 , over ten times of that for pristine CN. This work presents a strategy for designing multi-functional dual-atom based photocatalysts.

4.
Angew Chem Int Ed Engl ; 62(33): e202307123, 2023 Aug 14.
Article in English | MEDLINE | ID: mdl-37353890

ABSTRACT

The conventional industrial production of nitrogen-containing fertilizers, such as urea and ammonia, relies heavily on energy-intensive processes, accounting for approximately 3 % of global annual CO2 emissions. Herein, we report a sustainable electrocatalytic approach that realizes direct and selective synthesis of urea and ammonia from co-reduction of CO2 and nitrates under ambient conditions. With the assistance of a copper (Cu)-based salphen organic catalyst, outstanding urea (3.64 mg h-1 mgcat -1 ) and ammonia (9.73 mg h-1 mgcat -1 ) yield rates are achieved, in addition to a remarkable Faradaic efficiency of 57.9±3 % for the former. This work proposes an appealing sustainable route to converting greenhouse gas and waste nitrates by renewable energies into value-added fertilizers.

5.
J Am Chem Soc ; 144(44): 20372-20384, 2022 Nov 09.
Article in English | MEDLINE | ID: mdl-36283038

ABSTRACT

The poor durability of Pt-based nanoparticles dispersed on carbon black is the challenge for the application of long-life polymer electrolyte fuel cells. Recent work suggests that Fe- and N-codoped carbon (Fe-N-C) might be a better support than conventional high-surface-area carbon. In this work, we find that the electrochemical surface area retention of Pt/Fe-N-C is much better than that of commercial Pt/C during potential cycling in both acidic and basic media. In situ inductively coupled plasma mass spectrometry studies indicate that the Pt dissolution rate of Pt/Fe-N-C is 3 times smaller than that of Pt/C during cycling. Density functional theory calculations further illustrate that the Fe-N-C substrate can provide strong and stable support to the Pt nanoparticles and alleviate the oxide formation by adjusting the electronic structure. The strong metal-substrate interaction, together with a lower metal dissolution rate and highly stable support, may be the reason for the significantly enhanced stability of Pt/Fe-N-C. This finding highlights the importance of carbon support selection to achieve a more durable Pt-based electrocatalyst for fuel cells.

7.
Water Res ; 221: 118778, 2022 Aug 01.
Article in English | MEDLINE | ID: mdl-35752093

ABSTRACT

The electrochemical oxidation method is a promising technology for the degradation of perfluorooctane sulfonate (PFOS). However, the elimination processes of PFOS are still unknown, including the electron transfer pathway, key reactive sites, and degradation mechanism. Here, we fabricated diatomite and cerium (Ce) co-modified Sb2O3 (D-Ce/Sb2O3) anode to realize efficient degradation of PFOS via peroxymonosulfate (PMS) activation. The transferred electron and the generated hydroxyl radical (•OH) can high-effectively decompose PFOS. The electron can be rapidly transferred from the highest occupied molecular orbital of the PFOS to the lowest unoccupied molecular orbital of the PMS via the D-Ce/Sb2O3 driven by a potential energy difference under electrochemical process. The active site of Ce-O in the D-Ce/Sb2O3 can greatly reduce the migration distance of the electron and the •OH, and thus improving the catalytic activity for degrading various organic micropollutants with high stability. In addition, the electrochemical process shows strong resistance and tolerance to the changing pH, inorganic ions, and organic matter. This study offers insights into the electron transfer pathway and PMS activation mechanism in PFOS removal via electrochemical oxidation, paving the way for its potential application in water purification.


Subject(s)
Alkanesulfonic Acids , Water Pollutants, Chemical , Catalytic Domain , Fluorocarbons , Peroxides/chemistry , Water , Water Pollutants, Chemical/chemistry
8.
Chem Commun (Camb) ; 57(92): 12285-12288, 2021 Nov 19.
Article in English | MEDLINE | ID: mdl-34730570

ABSTRACT

Divergent synthesis provides an indispensable route to rapid acquisition of structurally diverse chemical scaffolds from identical starting materials. Herein, we describe unprecedented divergent annulations of o-hydroxyarylenaminones promoted by tert-butyl nitrite (TBN) under mild conditions. Two different types of benzo-oxa-heterocycle, including oximinochromanones and oximinocoumaranones, were smoothly assembled with a broad substrate scope and good functional group compatibility.

9.
Carbohydr Polym ; 266: 118122, 2021 Aug 15.
Article in English | MEDLINE | ID: mdl-34044938

ABSTRACT

Hydrogels often have poor mechanical properties which limit their application in load-bearing tissues such as muscle and cartilage. In this work, a near-infrared light-triggered stretchable thermal-sensitive hydrogel with ultra-high drug loading was developed by a combination of natural polymeric nanocrystals, a network of synthetic thermo-responsive polymer, and magnetic Fe3O4 nanoparticles. The hydrogels comprise cellulose nanocrystals (CNCs) decorated with Fe3O4 nanoparticles (Fe3O4/CNCs) dispersed homogeneously in poly(N-isopropylacrylamide) (PNIPAm) networks. The composite hydrogels exhibit an extensibility of 2200%. Drug loading of vancomycin (VCM) reached a high value of 10.18 g g-1 due to the dispersion of Fe3O4/CNCs and the interactions between the CNCs and the PNIPAm network. Importantly, the hydrogels demonstrated a thermo-response triggered by NIR, with the temperature increasing from 26 to 41 °C within 60 s. The hydrogels have high biocompatibility evidenced by cell proliferation tests, illustrating that these hydrogels are promising as dressings for wound closure, and wound healing.


Subject(s)
Cellulose/chemistry , Drug Carriers/chemistry , Hydrogels/chemistry , Magnetite Nanoparticles/chemistry , Acrylic Resins/chemistry , Acrylic Resins/radiation effects , Acrylic Resins/toxicity , Cellulose/radiation effects , Cellulose/toxicity , Drug Carriers/radiation effects , Drug Carriers/toxicity , Drug Liberation , HEK293 Cells , Humans , Hydrogels/radiation effects , Hydrogels/toxicity , Infrared Rays , Magnetite Nanoparticles/radiation effects , Magnetite Nanoparticles/toxicity , Nanocomposites/chemistry , Nanocomposites/radiation effects , Nanocomposites/toxicity , Porosity , Temperature , Vancomycin/chemistry
10.
J Org Chem ; 85(18): 11989-11996, 2020 Sep 18.
Article in English | MEDLINE | ID: mdl-32791836

ABSTRACT

Acyl oximes are directly used as the acyl radical precursors in the hydroacylation reactions for the first time. In this work, acyl radicals can be effectively generated via ß-scission of a phosphoranyl radical under photocatalytic conditions. As a result, the hydroacylation of alkenes triggered by the resulting acyl radicals leads to facile syntheses of a range of valuable ketones.

11.
ACS Appl Mater Interfaces ; 12(31): 34858-34872, 2020 Aug 05.
Article in English | MEDLINE | ID: mdl-32657571

ABSTRACT

The poor electronic conductivity of Na2FeSiO4 always limits its electrochemical reactivities and no effective solution has been found to date. Herein, the novel Ni-substituted Na2Fe1-xNixSiO4@C nanospheres (50-100 nm) encapsulated with a 3D hierarchical porous skeleton (named as alveolation-like configuration) constructed using in situ carbon are first synthesized via a facile sol-gel method, and the effects of Ni substitution combined with the design of a unique carbon network on Na-storage properties are assessed systematically, focusing on alleviating the inherent defects of the Na2FeSiO4 cathode material. A series of characterization technologies such as X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy and so forth, coupled with the electrochemical measurements and first-principles calculations, are used to explore the structure, morphology and electrochemical behaviors of the as-prepared materials. The results show that the synergism between Ni substitution and the special alveolation-like configuration enables fast Na ions mobility (from 10-14 to 10-12 cm2 s-1), reduces band gap energy (from 2.82 to 1.79 eV) and lowers Na-ion diffusion barriers, finally reciprocating the vigorous electrochemical kinetics of the electrode. Especially, the elaborately designed material-Na2Fe0.97Ni0.03SiO4@C-displays superior Na-storage properties of around 197.51 mA h g-1 (corresponding to 1.43 Na+ intercalation) at 0.1 C within 1.5-4.5 V along with desirable capacity retention (84.44% after 100 cycles), and the rate capability is also markedly enhanced (a capacity of 133.62 mA h g-1 at 2 C). Such the effective methodology employed in this work opens a potential pathway to synthesize the silicate cathode material with excellent electrochemical properties.

12.
ACS Nano ; 14(8): 9440-9448, 2020 Aug 25.
Article in English | MEDLINE | ID: mdl-32574040

ABSTRACT

Chiral photonic crystals derived from the self-assembly of cellulose nanocrystals (CNCs) have found important applications in optical devices due to the capacity to adjust the chiral nematic phase under external stimulus, in particular an applied magnetic field. To date, strong magnetic fields have been required to induce an optical response in CNC films. In this work, the self-assembly of films of CNCs can be tuned by applying an ultrasmall magnetic field. The CNCs, decorated with Fe3O4 nanoparticles (Fe3O4/CNCs), were dispersed in suspensions of neat CNCs so as to alter the magnetic response of the CNCs. A subsequent process of dispersion not only prevents the clumping of the magnetic nanoparticles but also enhances the sensitivity to an applied magnetic field. A small magnetic field of 7 mT can tune the self-assembly and the microstructure of the CNCs. The pitch of the chiral structure decreased with an increase in applied magnetic field, from 302 to 206 nm, for fields from 7 to 15 mT. This phenomenon is opposite that observed for neat CNCs, in which the pitch is observed to increase with an increase in the external magnetic strength. The optical response under application of an ultrasmall magnetic field could help with theoretical research and enable more applications, such as sensors or nanotemplating agents.

13.
ACS Appl Mater Interfaces ; 12(17): 19483-19494, 2020 Apr 29.
Article in English | MEDLINE | ID: mdl-32239909

ABSTRACT

A crucial challenge for the commercialization of Ni-rich layered cathodes (LiNi0.88Co0.09Al0.03O2) is capacity decay during the cycling process, which originates from their interfacial instability and structural degradation. Herein, a one-step, dual-modified strategy is put forward to in situ synthesize the yttrium (Y)-doped and yttrium orthophosphate (YPO4)-modified LiNi0.88Co0.09Al0.03O2 cathode material. It is confirmed that the YPO4 coating layer as a good ion conductor can stabilize the solid-electrolyte interface, while the formative strong Y-O bond can bridle TM-O slabs to intensify the lattice structure in the state of deep delithium (>4.3 V). In particular, both the combined advantages effectively withstand the anisotropic strain generated upon the H2-H3 phase transition and further alleviate the crack generation in unit-cell dimensions, assuring a high-capacity delivery and fast Li+ diffusion kinetics. This dual-modified cathode shows advanced cycling stability (94.1% at 1C after 100 cycles in 2.7-4.3 V), even at a high cutoff voltage and high rate, and advanced rate capability (159.7 mAh g-1 at 10C). Therefore, it provides a novel solution to achieve both high capacity and highly stable cyclability in Ni-rich cathode materials.

14.
ACS Appl Mater Interfaces ; 11(43): 40022-40033, 2019 Oct 30.
Article in English | MEDLINE | ID: mdl-31577125

ABSTRACT

The Ni-rich layered oxides are considered as a candidate of next-generation cathode materials for high energy density lithium-ion batteries; however, the finite cyclic life and poor thermostability impede their practical applications. There is often a tradeoff between structure stability and high capacity because the intrinsical instability of oxygen framework will lead to the structural transformation of Ni-rich materials. Because of the strong binding energy between the Te atom and O atom, herein a new technology of surface tellurium (Te) doping in the Ni-rich layered oxide (LiNi0.88Co0.09Al0.03O2) is proposed to settle the above predicament. Based on density function theory calculations and experiment analysis, it has been confirmed that the doped Te6+ ions are positioned in the TM layer near the oxide surface, which can constrain the TM-O slabs by strong Te-O bonds and prevent oxygen release from the surface, thus enhancing the stability of the lattice framework in deep delithium (>4.3 V). Especially, 1 wt % Te doping (Te 1%-NCA) shows the superiority in performance improvement. Furthermore, the reversibility of H2-H3 phase transition is also improved to relieve effectively the capacity decline and the structural transformations at extended cycling, which can facilitate the fast Li+ diffusion kinetic. Consequently, Te 1%-NCA cathode exhibits the improved cycling stability even at high voltages (4.5 and 4.7 V), good rate capability (159.2 mA h g-1 at 10 C), and high thermal stability (the peak temperature of 258 °C). Therefore, the appropriate Te surface doping provides a significant exploration for industrial development of the high-performance Ni-rich cathode materials with high capacity and structural stability.

15.
ACS Appl Mater Interfaces ; 11(35): 31980-31990, 2019 Sep 04.
Article in English | MEDLINE | ID: mdl-31403763

ABSTRACT

Na2FeSiO4, as one of the promising cathode materials in sodium-ion batteries, has attracted great interests. However, studies on the kinetic behaviors of Na ions insertion/extraction in Na2FeSiO4 composite electrode have been barely considered, until now. Importantly, the specific capacity and rate capability of Na2FeSiO4 cathode materials are greatly correlated with the kinetics of Na+ transfer in the host material. Herein, on the basis of the characterizations of microstructure and morphologies (i.e., Rietveld refinement, FESEM, HRTEM, etc.), the electrochemical kinetics of Na ions extraction in Na2FeSiO4/C electrode are first studied in detail via two electrochemical techniques (EIS and GITT), establishing the rate-controlling steps of Na+ transport in Na2FeSiO4/C, evaluating series of kinetic parameters, as well as calculating the Na+ diffusion coefficient at various state-of-desodiation. Changes of impedance response of Na2FeSiO4/C electrode depending on the different levels of desodiation show that a serial features of electrode process for Na ions migration have tremendous discrepancies, indicating that the kinetics of Na+ extraction from Na2FeSiO4/C electrode are largely influenced by different electrode reaction processes. These results provide useful insight into the inner properties of Na2FeSiO4/C electrode, and it is significant to optimize the electrochemical performance of Na2FeSiO4/C. Moreover, two models of equivalent circuits are also constructed to simulate the electrode processes and describe the behaviors of Na ions transfer in Na2FeSiO4/C.

16.
Chemistry ; 25(18): 4673-4677, 2019 Mar 27.
Article in English | MEDLINE | ID: mdl-30840339

ABSTRACT

One-pot ring-opening/ring-closure process of combining methyleneindolinone with 3-aminooxindole has been developed in this work. Novel polycyclic spirooxindoles were efficiently assembled under mild conditions in high yields (up to 95 %) with moderate to good diastereoselectivities (up to >95:5 d.r.) through simple filtration.

17.
Gut ; 68(10): 1827-1837, 2019 10.
Article in English | MEDLINE | ID: mdl-30705050

ABSTRACT

OBJECTIVE: Chronic pancreatitis (CP) is an inflammatory disease with progressive fibrosis leading to exocrine and endocrine dysfunction. Currently, there are no approved effective therapies for CP. Stimulator of interferon genes (STING) signalling is a key innate immune sensor of DNA. In this study, we evaluated the role of STING signalling in CP. DESIGN: We used an experimental model of CP to test the effect of STING signalling in STING wild-type and knockout mice as well as bone marrow chimaeras (BMCs). STING was activated using a pharmacological agent. Since we found changes in Th17 cells, we used neutralising and control antibodies to determine the role of IL-17A. The effect of STING signalling was further explored in IL-17A generation and we examined the effect of IL-17A on pancreatic stellate cells (PSCs). Human pancreas from patients with CP and without CP were also stained for IL-17A. RESULTS: STING activation decreased CP-associated pancreatic inflammation and fibrosis, whereas absence of STING led to worsening of the disease. BMCs showed that leucocytes play an important role in STING signalling-mediated amelioration of experimental CP. STING deletion was associated with increased Th17 cell infiltration in the pancreas, whereas STING agonist limited this Th17 response. Importantly, anti-IL-17A antibody treatment mitigated the severity of CP in the absence of STING signalling. STING deficiency promoted Th17 polarisation and PSCs express functional IL-17 receptor by upregulating fibrosis genes. Compared with tumour margins, pancreas from patients with CP had significant increase in IL-17A+ cells. CONCLUSION: Unlike acute pancreatitis, STING activation is protective in CP. STING signalling is important in regulating adaptive immune responses by diminishing generation of IL-17A during CP and presents a novel therapeutic target for CP.


Subject(s)
Gene Expression Regulation , Immunity, Cellular/genetics , Membrane Proteins/genetics , Pancreatitis/immunology , Th17 Cells/immunology , Animals , Blotting, Western , Cells, Cultured , Chronic Disease , DNA/genetics , Disease Models, Animal , Humans , Immunohistochemistry , Mice , Mice, Inbred C57BL , Mice, Knockout , Pancreatitis/metabolism , Pancreatitis/pathology , Polymerase Chain Reaction , Signal Transduction , Th17 Cells/metabolism
18.
Materials (Basel) ; 11(12)2018 Dec 17.
Article in English | MEDLINE | ID: mdl-30562972

ABSTRACT

Sodium-ion batteries are promising alternative electrochemical energy storage devices due to the abundance of sodium resources. One of the challenges currently hindering the development of the sodium-ion battery technology is the lack of electrode materials suitable for reversibly storing/releasing sodium ions for a sufficiently long lifetime. Redox-active polymers provide opportunities for developing advanced electrode materials for sodium-ion batteries because of their structural diversity and flexibility, surface functionalities and tenability, and low cost. This review provides a short yet concise summary of recent developments in polymer electrode materials for sodium-ion batteries. Challenges facing polymer electrode materials for sodium-ion batteries are identified and analyzed. Strategies for improving polymer electrochemical performance are discussed. Future research perspectives in this important field are projected.

19.
ACS Appl Mater Interfaces ; 10(50): 43730-43739, 2018 Dec 19.
Article in English | MEDLINE | ID: mdl-30475572

ABSTRACT

Redox-active polyimide materials hold a great promise for electrochemical energy storage applications, especially for flexible energy storage devices. However, the low utilization efficiency due to poor electrical conductivity of the materials remains one of the greatest challenges. In this work, we designed and prepared polyimide-graphene composite materials and tested their electrochemical properties in sodium-ion capacitors. By manipulating the interfacial chemistry and interactions between the polyimide and graphene, composite electrode materials with different polyimide particle sizes and morphologies were obtained. Sodium-ion storage capacity was significantly improved, from ∼50 mAh g-1 for pure polyimide to 225 mAh g-1 for a polyimide-graphene composite. A hybrid sodium-ion capacitor fabricated with freestanding polyimide-graphene composite as the negative electrode and reduced graphene oxide as the positive electrode delivered energy densities of 55.5 and 21.5 Wh kg-1 at power densities of 395 and 3400 W kg-1, respectively. A flexible sodium-ion capacitor with outstanding mechanical properties was also demonstrated.

20.
J Org Chem ; 83(19): 12284-12290, 2018 10 05.
Article in English | MEDLINE | ID: mdl-30183297

ABSTRACT

A facile and enantioselective access to a functionalized octahydroacridine scaffold was developed via an organocatalytic domino sequence between cyclohexenone and 2- N-substituted benzaldehyde. High levels of yields (up to 99%) and enantioselectivities (up to 99:1 er) were readily achieved in this developed organocatalytic transformation, which holds promising applications in the construction of complex multicyclic systems for further pharmacological studies.

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