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1.
Poult Sci ; 103(4): 103476, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38401224

RESUMO

In the pigeon industry, treating and preventing diarrhea is vital because it is a serious health problem for pigeons. This study investigated the incidence of diarrhea in 3 pigeon farms in Shanghai, and analyzed the microflora through 16S rDNA high-throughput sequencing. Four strains of Escherichia coli (E. coli) isolated from pigeon diarrhea feces were administered via gavage to healthy pigeons, with each pigeon receiving 2 × 108 CFU. Pigeons that developed diarrhea after E. coli challenge were treated with 3 g of Lactobacillus salivarius SNK-6 (L. salivarius SNK-6) health sand (1.6 × 107 CFU/g). Then, a mass feeding experiment expanded to 688 pairs of pigeons with 3 replicates, each receiving 3 g of health sand containing L. salivarius SNK-6 (1.6 × 107 CFU/g) every 2 wk, and fecal status monitored and recorded. The study found that the relative abundance of the Lactobacillus genus and L. salivarius in feces from pigeons with diarrhea was significantly lower than in normal pigeon feces (P < 0.05). In contrast, E. coli showed a higher abundance and diversity in feces from pigeons with diarrhea than in normal feces (P < 0.05). Three out of the 4 isolated E. coli strains caused pigeon diarrhea, resulting in a significant reduction in microbial diversity in fecal samples (P < 0.05). Both the small group attack experiment and the mass-fed additive experiment in pigeon farms demonstrated that feeding L. salivarius SNK-6 effectively cured and prevented diarrhea. Pigeons fed with L. salivarius SNK-6 exhibited no diarrhea, while the control group had a 10% diarrhea rate. In summary, a deficiency of Lactobacillus or a high abundance of E. coli in the intestine could easily cause pigeon diarrhea. Feeding L. salivarius SNK-6 could treat pigeon diarrhea, and continuous supplementation could maintain stable preventive effects.


Assuntos
Lactobacillus , Ligilactobacillus salivarius , Animais , Lactobacillus/genética , Columbidae , Escherichia coli , Areia , China , Galinhas , Diarreia/prevenção & controle , Diarreia/veterinária , Fezes
2.
Sensors (Basel) ; 23(22)2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38005499

RESUMO

The rapid development and extensive application of the Internet of Things (IoT) have brought new challenges and opportunities to the field of communication. By integrating quantum secure communication with the IoT, we can provide a higher level of security and privacy protection to counteract security threats in the IoT. In this paper, a hybrid quantum communication scheme using six-qubit entangled states as a channel is proposed for specific IoT application scenarios. This scheme achieves hierarchical control of communication protocols on a single quantum channel. In the proposed scheme, device A transmits data to device B through quantum teleportation, while device B issues control commands to device A through remote quantum state preparation technology. These two tasks are controlled by control nodes C and D, respectively. The transmission of information from device A to device B is a relatively less important task, which can be solely controlled by control node C. On the other hand, issuing control commands from device B to device A is a more crucial task requiring joint control from control nodes C and D. This paper describes the proposed scheme and conducts simulation experiments using IBM's Qiskit Aer quantum computing simulator. The results demonstrate that the fidelity of the quantum teleportation protocol (QTP) and the remote state preparation protocol (RSP) reach an impressive value of 0.999, fully validating the scheme's feasibility. Furthermore, the factors affecting the fidelity of the hybrid communication protocol in an IoT environment with specific quantum noise are analyzed. By combining the security of quantum communication with the application scenarios of the IoT, this paper presents a new possibility for IoT communication.

3.
Sensors (Basel) ; 23(20)2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37896568

RESUMO

With the continuous development of the Internet of Things (IoT) technology, the industry's awareness of the security of the IoT is also increasing, and the adoption of quantum communication technology can significantly improve the communication security of various devices in the IoT. This paper proposes a scheme of controlled remote quantum state preparation and quantum teleportation based on multiple communication parties, and a nine-qubit entanglement channel is used to achieve secure communication of multiple devices in the IoT. The channel preparation, measurement operation, and unitary operation of the scheme were successfully simulated on the IBM Quantum platform, and the entanglement degree and reliability of the channel were verified through 8192 shots. The scheme's application in the IoT was analyzed, and the steps and examples of the scheme in the secure communication of multiple devices in the IoT are discussed. By simulating two different attack modes, the effect of the attack on the communication scheme in the IoT was deduced, and the scheme's high security and anti-interference ability was analyzed. Compared with other schemes from the two aspects of principle and transmission efficiency, it is highlighted that the advantages of the proposed scheme are that it overcomes the single fixed one-way or two-way transmission protocol form of quantum teleportation in the past and can realize quantum communication with multiple devices, ensuring both security and transmission efficiency.

4.
Nano Lett ; 23(21): 10074-10080, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37903224

RESUMO

By stacking monolayer black phosphorus (MBP) with nonpolarized and ferroelectric polarized bilayer hexagonal boron nitride (h-BN), we demonstrate that ferroelectric proximity effects have a strong influence on the charge carrier lifetime of MBP using nonadiabatic (NA) molecular dynamics simulations. Through enhancing the motion of phosphorus atoms, ferroelectric polarization enhances the overlap of electron-hole wave functions that improves NA coupling and decreases the bandgap, resulting in a rapid electron-hole recombination completing within a quarter of nanoseconds, which is two times shorter than that in nonpolarized stackings. In addition to the dominant in-plane Ag2 mode in free-standing MBP, the out-of-plane high-frequency Ag1 and low-frequency interlayer breathing modes presented in the heterojunctions drive the recombination. Notably, the resonance between the breathing mode within bilayer h-BN and the B1u mode of MBP provides an additional nonradiative channel in ferroelectric stackings, further accelerating charge recombination. These findings are crucial for charge dynamics manipulation in two-dimensional materials via substrate ferroelectric proximity effects.

5.
J Am Chem Soc ; 145(41): 22826-22835, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37796526

RESUMO

A twist angle at a van der Waals junction provides a handle to tune its optoelectronic properties for a variety of applications, and a comprehensive understanding of how the twist modulates electronic structure, interlayer coupling, and carrier dynamics is needed. We employ time-dependent density functional theory and nonadiabatic molecular dynamics to elucidate angle-dependent intervalley carrier transfer and recombination in bilayer WS2. Repulsion between S atoms in twisted configurations weakens interlayer coupling, increases the interlayer distance, and softens layer breathing modes. Twisting has a minor influence on K valleys while it lowers Γ valleys and raises Q valleys because their wave functions are delocalized between layers. Consequently, the reduced energy gaps between the K and Γ valleys accelerate the hole transfer in the twisted structures. Intervalley electron transfer proceeds nearly an order of magnitude faster than hole transfer. The more localized wave functions at K than Q values and larger bandgaps result in smaller nonadiabatic couplings for intervalley recombination, making it 3-4 times slower in twisted than high-symmetry structures. B2g breathing, E2g in-plane, and A1g out-of-plane modes are most active during intervalley carrier transfer and recombination. The faster intervalley transfer and extended carrier lifetimes in twisted junctions are favorable for optoelectronic device performance.

6.
Materials (Basel) ; 16(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36837127

RESUMO

Crystal coating is an important process in laser crystal applications. According to the crystal characteristics of neodymium-doped yttrium vanadate (Nd:YVO4), its intrinsic parameters, and optical film design theory, Ta2O5 and SiO2 were selected separately as high and low refractive index materials. The optical properties and surface roughness of the films were characterized by OptiLayer and Zygo interferometers, and the effects of ion source bias on refractive index and surface roughness were investigated so that the optimal ion source parameters were determined. Optical monitoring and quartz crystal control were combined to accurately control the thickness of each film layer and to reduce the monitoring error of film thickness. The prepared crystal device was successfully applied to the 1176 nm laser output system.

7.
JACS Au ; 2(1): 234-245, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35098240

RESUMO

Polarons play a major role in determining the chemical properties of transition-metal oxides. Recent experiments show that adsorbates can attract inner polarons to surface sites. These findings require an atomistic understanding of the adsorbate influence on polaron dynamics and lifetime. We consider reduced rutile TiO2(110) with an oxygen vacancy as a prototypical surface and a CO molecule as a classic probe and perform ab initio adiabatic molecular dynamics, time-domain density functional theory, and nonadiabatic molecular dynamics simulations. The simulations show that subsurface polarons have little influence on CO adsorption and CO can desorb easily. On the contrary, surface polarons strongly enhance CO adsorption. At the same time, the adsorbed CO attracts polarons to the surface, allowing them to participate in catalytic processes with CO. The CO interaction with polarons changes their orbital origin, suppresses polaron hopping, and stabilizes them at surface sites. Partial delocalization of polarons onto CO decouples them from free holes, decreasing the nonadiabatic coupling and shortening the quantum coherence time, thereby reducing charge recombination. The calculations demonstrate that CO prefers to adsorb at the next-nearest-neighbor five-coordinated Ti3+ surface electron polaron sites. The reported results provide a fundamental understanding of the influence of electron polarons on the initial stage of reactant adsorption and the effect of the adsorbate-polaron interaction on the polaron dynamics and lifetime. The study demonstrates how charge and polaron properties can be controlled by adsorbed species, allowing one to design high-performance transition-metal oxide catalysts.

8.
Environ Sci Pollut Res Int ; 29(21): 31441-31452, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35006570

RESUMO

A comprehensive study was conducted on the characteristics of oxygen-controlled carbonization process of sewage sludge (SS) using thermogravimetric analysis and lab-scale carbonization experiment. Reaction temperature of SS carbonization was varied between 250 and 650 °C in carrier gas with different O2 contents. The thermal process of SS in low oxygen could be divided into three stages: dehydration (below 160 °C), devolatilization (160-380 °C), stubborn volatile decomposition and fixed carbon combustion (380-600 °C). Based on Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods, the reaction activation energy (E) of SS carbonization process in 10% O2 was the lowest, with values of 98.50 kJ mol-1 (KAS) and 103.49 kJ mol-1 (FWO). The properties of the obtained char, tar, and gas products were analyzed by FTIR and GC-MS. With the increase of carbonization temperature, char yield decreased and gas yield increased. The highest yield of tar was 27.76% (N2) and 27.04% (10% O2) at 450 °C. Low-oxygen atmosphere at the same temperature did not change the yield of char but increased the fixed carbon content and its aromaticity. Oxygen would participate in secondary cracking in tar and promote gas generation above 350 °C. It was found that the presence of oxygen not only increased the concentration of H2, CO, and CH4 in gas product, but also improved the quality of tar in terms of high aromatic content and low nitrogen-containing compounds.


Assuntos
Oxigênio , Esgotos , Carbono , Cinética , Temperatura
9.
J Phys Chem Lett ; 12(44): 10886-10892, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34730966

RESUMO

The nonadiabatic (NA) process is crucial to photochemistry and photophysics and requires an atomistic understanding. However, conventional NA molecular dynamics (MD) for condensed-phase materials on the nanoscale are generally limited to the semilocal exchange-correlation functional, which suffers from the bandgap and thus NA coupling (NAC) problems. We consider TiO2 and a black phosphorus monolayer as two prototypical systems, perform NA-MD simulations of nonradiative electron-hole recombination, and demonstrate for the first time that density functional theory (DFT) half-electron self-energy correction can reproduce the bandgap, effective masses of carriers, luminescence line widths, NAC, and excited-state lifetimes of the two systems at the hybrid functional level while the computational cost remains at that of the Predew-Burke-Ernzerhof functional. Our study indicates that the DFT-1/2 method can greatly accelerate NA-MD simulations while maintaining the accuracy of the hybrid functional, providing an advantage for studying photoexcitation dynamics for large-scale condensed-phase materials.

10.
J Phys Chem Lett ; 12(6): 1664-1670, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33555885

RESUMO

Metal halide perovskites are promising materials for photovoltaics and optoelectronics. However, transfer of an electron from perovskite to oxygen leads to the formation of superoxide that significantly decreases the stability and charge carrier lifetime of perovskites, which constitutes major issues for real applications. Using nonadiabatic (NA) molecule dynamics simulations, we demonstrate that the introduction of a perylene diimide (PDI) molecule into the CH3NH3PbI3 system adsorbed with an oxygen molecule creates a midgap state above the trap state generated by the oxygen molecule, and thus the PDI midgap state can rapidly capture the photogenerated electron of perovskite at about 100 ps prior to the O2-related trap state, which takes about double the time. The route simultaneously avoids the formation of superoxide and enhances the stability of perovskites. The fast electron trapping originates from the strong NA coupling and small energy gap between the PDI midgap state and the CH3NH3PbI3 conduction band minimum. Our simulations suggest that a rational choice an electron-accepting molecule can improve the stability and performance of perovskite solar cells and photoelectric devices.

11.
Waste Manag ; 121: 33-41, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33341692

RESUMO

Bottom ash contains unfavorable contaminants that could leach into the circulating water used for wet treatment, and its improper disposal of bottom ash could cause ecological pollution. This study was to discuss the partition of heavy metals and salts of bottom ash into circulating water and ash stockpile runoff in wet treatment plants in southern China. The leachability of bottom ash before and after the wet treatment was also investigated. The checked heavy metals Pb, Cu, and Ni and dissolved salts Cl- and SO42- show lower available fractions in leachate from the treated bottom ash than that in raw bottom ash. Circulating water is contaminated by target heavy metals, which the contents of Cu and Pb is higher than its limit for urban wastewater discharge. The circulating water owned the highest concentration of Cl- and SO42-, above10000 mg/L, and 1100 mg/L, which is far higher than the limits. The detected heavy metals, Cl- and SO42- in runoff also exceed the limits for urban wastewater discharge. Locations for bottom ash processing and storage sites should be selected to control and prevent any leaching and runoff impacts. Any runoff and circulation water should be discharged to the lined landfill's leachate collection system or suitable industrial wastewater treatment facilities.


Assuntos
Metais Pesados , Eliminação de Resíduos , China , Cinza de Carvão , Incineração , Metais Pesados/análise , Sais , Resíduos Sólidos/análise
12.
Phys Chem Chem Phys ; 21(41): 23094-23101, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31603158

RESUMO

Proton exchange fuel cells (PEFCs) are one of the most popular and promising energy conversion devices because of their highly stable and efficient membranes in acidic media, but there is a lack of durable non-noble metal electrocatalysts suitable for acidic environments. Herein, we designed a new type of electrocatalysts consisting of transition metal halide molecules covered by graphene sheets, which is supported by experiments. To rapidly screen the best catalysts from numerous candidate materials, the electronic structures, reaction free energies and overpotentials of those graphene-covered halide catalysts were studied by the first-principles calculations to predict the catalytic activities for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). An intrinsic descriptor, the electrostatic force induced by the metallic ions, was found to well describe the catalytic activities and provide a better understanding of the local electrical field effects on catalytic activities. The spin-down d-band center was also introduced to describe catalytic activities of the catalysts. The results demonstrate that the graphene-covered CrBr2 shows the best bifunctional catalytic activities for fuel cells while graphene-covered CoF2 could well facilitate H2O2 production. These catalysts are better than the best commercial noble metal catalysts (e.g., Pt and RuO2) in terms of overpotentials and activities. This work provides a theoretical base for rationally designing durable electrocatalysts with excellent catalytic activities.

13.
ACS Appl Mater Interfaces ; 11(28): 25264-25270, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31265219

RESUMO

Introducing anion vacancies on two-dimensional transition-metal dichalcogenides (TMDs) would significantly improve their catalytic activity. In this work, we proposed a solid-phase reduction (SPR) strategy to simultaneously achieve efficient exfoliation and controlled generation of chalcogen vacancies on TMDs. Consecutive sulfur vacancies were successfully created on the basal plane of the bulk MoS2 and WS2, and their interlamellar distances were distinctly expanded after the SPR treatment (about 16%), which can be conveniently exfoliated by only gentle shaking. The S-vacancy significantly increases the hydrogen-evolution reaction activity of the MoS2 and WS2 nanosheets, with overpotential of -238 and -241 mV at 10 mA cm-2, respectively. We anticipate that our SPR strategy will supply a general platform for the development of TMD-based electrocatalysts for industrial water splitting and hydrogen production in the near future.

14.
Adv Mater ; 31(13): e1805252, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30536475

RESUMO

Carbon nanomaterials are promising metal-free catalysts for energy conversion and storage, but the catalysts are usually developed via traditional trial-and-error methods. To rationally design and accelerate the search for the highly efficient catalysts, it is necessary to establish design principles for the carbon-based catalysts. Here, theoretical analysis and material design of metal-free carbon nanomaterials as efficient photo-/electrocatalysts to facilitate the critical chemical reactions in clean and sustainable energy technologies are reviewed. These reactions include the oxygen reduction reaction in fuel cells, the oxygen evolution reaction in metal-air batteries, the iodine reduction reaction in dye-sensitized solar cells, the hydrogen evolution reaction in water splitting, and the carbon dioxide reduction in artificial photosynthesis. Basic catalytic principles, computationally guided design approaches and intrinsic descriptors, catalytic material design strategies, and future directions are discussed for the rational design and synthesis of highly efficient carbon-based catalysts for clean energy technologies.


Assuntos
Carbono/química , Fontes de Energia Elétrica , Nanoestruturas/química , Energia Solar , Materiais Biomiméticos/química , Dióxido de Carbono/química , Catálise , Corantes/química , Hidrogênio/química , Iodo/química , Modelos Moleculares , Oxirredução , Oxigênio/química , Processos Fotoquímicos , Fotossíntese , Água/química
15.
Carbohydr Polym ; 140: 356-61, 2016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-26876862

RESUMO

In this work, we have proven that starch nanofibrous membranes with high tensile strength, water stability and non-cytotoxicity can be produced by electrospinning of starch solution and post-treatment with GTA in vapor phase. GTA vapor phase crosslinking plays a key role in forming water-stable nanofiber membrane and improving the mechanical properties. Comparing with non-crosslinked starch fibers, the crosslinked fibers are increased by nearly 10 times in tensile strength. The crosslinked starch fibrous membranes are non-cytotoxic. They may find applications in the fields of tissue engineering, pharmaceutical therapy and medical.


Assuntos
Antibacterianos/química , Eletricidade , Glutaral/química , Amido/química , Antibacterianos/farmacologia , Estabilidade de Medicamentos , Escherichia coli/efeitos dos fármacos , Temperatura , Resistência à Tração , Volatilização , Água/química
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