Designing electrochemical catalysts has become a research hotspot due to their accelerating the polysulfide conversion of the sulfur cathode to inhibit the“shuttle effect”in lithium-sulfur ***,it is still a great ch...
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Designing electrochemical catalysts has become a research hotspot due to their accelerating the polysulfide conversion of the sulfur cathode to inhibit the“shuttle effect”in lithium-sulfur ***,it is still a great challenge to design the heterogeneous selective electrochemical catalyst for inhibiting the“shuttle effect”.Herein,nickel cobalt phosphide and cobalt phosphide as the heterogeneous catalyst active sites embedded in the nitrogen-doped hollow carbon nanocages(NiCoP@CoP/NC)are reported,used for multi-step and multi-phase sulfur electrode reaction,and it is found that metal-sulfur d-p hybridization can effectively indicate the intrinsic catalytic activity of metal *** of labor and cooperation of the bi-active NiCoP@CoP as heterogeneous catalysts propel the stepwise polysulfide *** and CoP sites preferentially accelerate the long-chain polysulfide conversion reaction(S_(8)■LiPSs)and the short-chain polysulfide conversion reactions(LiPSs■Li_(2)S),***,the hollow and porous N-doped carbon structure can successfully suppress the volume effect and improve the conductivity of the sulfur *** unique design can obtain an effective inhibition of the shuttle effect and rapid electrode *** a result,Li-S batteries demonstrate a high initial capacity of 1063 mAh g^(-1) and a low-capacity decay of 0.04% per cycle within 1000 *** work provides a feasible idea for the design of host materials in Li-S batteries.
The precise detection and measurement of dopamine(DA),a crucial neurotransmitter in the human body,plays a significant role in diagnosing,preventing,and treating neurological diseases associated with its levels.A hi...
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The precise detection and measurement of dopamine(DA),a crucial neurotransmitter in the human body,plays a significant role in diagnosing,preventing,and treating neurological diseases associated with its levels.A highly sensitive DA electrochemical sensor was constructed by combining molybdenum disulfide quantum dots(MSQDs) with multiwalled carbon nanotubes(MWCNTs).The MSQDs were synthesized using the shear exfoliation *** sensors consist of MSQDs with Mo-S edge catalytic centers for the DA redox reaction,and MWCNTs amplify the sensor *** linearity of the sensor for the detection of DA was tested in the presence of ascorbic acid(AA,50 μmol·L-1) and uric acid(UA,200 μmol·L-1),and exhibited linearity from 2 to 966 μmol·L-1of DA with 0.097 μA(mol·L-1)-1sensitivity and a low limit of detection of0.6 μmol·L-1(the ratio between signal and noise,S/N=3).Moreover,the sensitivity and selectivity of the sensor were also studied using *** is no increase in amperometric current after adding the most potentially interfering *** sensor was successfully applied to recover DA in human blood sera ***,machine learning algorithms were operated to aid in the near-precise detection of DA in the heterogeneous mixture containing AA and *** algorithms facilitate the identification and quantification of DA amidst coexisting interferents,including AA,that are commonly present in biological matrices.
The adoption of container-based cloud computing services has been prevalent, especially with the introduction of Kubernetes, which enables the automated deployment, scaling, and administration of applications in conta...
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Recently,Mg_(3)Sb_(2)-xBixalloys have attracted intensive attention,with the aim of maximizing the electrical transport performance via donor element doping,increasing the grain size,as well as electronic band structu...
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Recently,Mg_(3)Sb_(2)-xBixalloys have attracted intensive attention,with the aim of maximizing the electrical transport performance via donor element doping,increasing the grain size,as well as electronic band structure ***,less attention has been paid to other significant factors,like how these intrinsic point defects and accompanied secondary phases influence thermoelectric *** this study,the microstructure and thermoelectric transport properties of Mg_(3.2)Sb_(0.5)Bi_(1.495-x)Te_(0.005)(x=0~0.2)compounds were systematically investigated,where tuning the Bi content shows the counter-intuitive impact on the thermoelectric *** was found that the Bipoor environment associated with Bi impurities facilitated the increment of cation vacancy formation energy and then increased the carrier concentration,leading to the enhancement of power ***,the reduction of Bi-rich second phase content weakened the carrier scattering by grain boundaries whereas high carrier mobility was ***,the bipolar thermal conductivity decreased obviously due to the increased majority carrier concentration to suppress the intrinsic *** synergistic optimization pushes the average ZT value(300-573 K)up to 0.95 in the Mg_(3.2)Sb_(0.5)Bi_(1.295)Te_(0.005)***,the calculated single-leg conversion efficiency is increased up to 9.7%with the hot-side temperature of 573 K,as the record-high value in this system.
Non-radiative optical modes attracted enormous attention in optics due to strong light confinement and giant Q-factor at its spectral *** destructive interference of multipoles leads to zero net-radiation and strong f...
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Non-radiative optical modes attracted enormous attention in optics due to strong light confinement and giant Q-factor at its spectral *** destructive interference of multipoles leads to zero net-radiation and strong field *** radiationless states disappear in the far-field,localize enhanced near-field and can be excited in *** the other hand,the optical modes turn out to be completely confined due to no losses at discrete point in the radiation continuum,such states result in infinite Q-factor and *** radiationless states provide a suitable platform for enhanced light matter interaction,lasing,and boost nonlinear processes at the state *** modes are widely investigated in different material configurations for various applications in both linear and nonlinear metasurfaces which are briefly discussed in this review.
Zeolite imidazole skeleton(ZIF-8)is a promising option for self-cleaning of building exterior walls due to its large specific surface area,high antibacterial activity and low ***,it suffers from low antibacterial effi...
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Zeolite imidazole skeleton(ZIF-8)is a promising option for self-cleaning of building exterior walls due to its large specific surface area,high antibacterial activity and low ***,it suffers from low antibacterial efficiency and yield under visible light *** address the issues,we developed the photocatalytic materials T-ZIF-8-TDI(thermally treated-ZIF-8-toluene 2,4-diisocyanate)by modifying ZIF-8 with thermal oxygen sensitization and chemical *** results show that the yield of T-ZIF-8-TDI photocatalytic antibacterial agent is increased to 11.5 times of that of T-ZIF-8,while maintaining the crystal structure of T-ZIF-8 and thermal stability up to 60℃.Furthermore,T-ZIF-8-TDI exhibits extended optical response range to the nearinfrared region,significantly narrowed band gap,improved photogenerated elec tron-hole separation efficiency,reduced recombination rate,and excellent photocatalytic *** the concentration of antibacterial agent is 600 mg·L^(-1),the antibacterial rate of Escherichia coli(***)reaches 99.99%irradiated by visible light for30 min,and when the concentration of antibacterial agent is 200 mg·L^(-1),the antibacterial rate of Staphylococcus aureus(***)reaches 99.99%irradiated by visible light for 25 *** also analyzed the reasons in detail from the aspects of bacterial species and antibacterial mechanism,and proposed the antibacterial mechanism of·O_(2)^(-)and h^(+)as the main active *** findings suggest that T-ZIF-8-TDI photocatalytic antibacterial agent has potential for use in self-cleaning of building exterior walls.
Lithium-sulfur(Li-S)batteries with high energy density suffer from the soluble lithium polysulfide species,Traditional metal sulfides containing a single metal element used as electrocatalysts for Li-S batteries commo...
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Lithium-sulfur(Li-S)batteries with high energy density suffer from the soluble lithium polysulfide species,Traditional metal sulfides containing a single metal element used as electrocatalysts for Li-S batteries commonly have limited catalytic abilities to improve battery ***,based on the Hume-Rothery rule and solvothermal method,the high-entropy sulfide NiCoCuTiVS_(x)derived from Co_(9)S_(8)was designed and synthesized,to realize the combination of small local strain and excellent catalytic *** all five metal elements(Ni,Co,Cu,Ti,and V)capable of chemical interactions with soluble polysulfides,NiCoCuTiVS_(x)exhibited strong chemical confinement of polysulfides and promoted fast kinetics for polysulfides ***,the S/NiCoCuTiVS_(x)cathode can maintain a high discharge capacity of 968.9 mA h g^(-1)after 200 cycles at 0.5 C and its capacity retention is 1.3 times higher than that of S/Co_(9)S_(8).The improved cycle stability can be attributed to the synergistic effect originating from the multiple metal elements,coupled with the reduced nucleation and activation barriers of Li_(2)*** present work opens a path to explore novel electrocatalyst materials based on high entropy materials for the achievement of advanced Li-S batteries.
Energetic compounds bearing the trinitromethyl group are garnering broad attraction as potential candidates for a new generation of high energy dense *** this work,an effective dual modulation strategy involving both ...
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Energetic compounds bearing the trinitromethyl group are garnering broad attraction as potential candidates for a new generation of high energy dense *** this work,an effective dual modulation strategy involving both molecular isomerization and crystal morphology control was employed to design and optimize trinitromethyl-oxadiazole with improved comprehensive *** this dual strategy,3,5-bis(trinitromethyl)-1,2,4-oxadiazole(3)was synthesized,resulting in the formation of two distinct crystal morphologies(needle and sheet)corresponding to two crystal forms(3-a and3-b).Encouragingly,while maintaining ultra-high oxygen balance(21.73%),3 achieves impressive densities(1.97-1.98 g/cm^(3)).To our knowledge,the density of 1.98 g/cm^(3)for 3-a sets a new record among that of nitrogen-rich monocyclic ***,practical crystal morphology prediction was creatively introduced to guide the experimental crystallization conditions of 3,increasing the impact sensitivity and friction sensitivity from 1 J to 80 N(3-a)to 10 J and 240 N(3-b),***,the crystal structural analyses and theoretical calculations were conducted to elucidate the reasons of differences between 3-a and 3-b in density and *** work provides an efficient strategy to enhance performance of trinitromethyl derivatives,broadening the path and expanding the toolbox for energetic materials.
In this study,the PH13-8Mo stainless steel parts doped without and with cerium(Ce)were fabricated via laser powder bed fusion followed by post-heat treatment,and systematically compared in terms of microstructure,phas...
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In this study,the PH13-8Mo stainless steel parts doped without and with cerium(Ce)were fabricated via laser powder bed fusion followed by post-heat treatment,and systematically compared in terms of microstructure,phase constituent,and tensile *** comparative results show that doping Ce-modified grains with the equiaxed morphology and finer size,increased the mechanical stability of austenite,and enhanced the sphericity of oxide inclusion in the resultant ***,the coherency between the newly-formed CeAlO 3 inclusion and matrix was effectively im proved after doping Ce,as compared to the original aluminum oxide inclusion without doping *** resultant PH13-8Mo parts doped with Ce yielded an ultimate tensile strength of 1446±20 MPa with a fracture elongation of 16.0%±1.5%,for the first time meeting the AMS 5629E H1000 standard for the PH13-8Mo made by additive manufacturing(AM).The enhanced strength results from the strengthening effects of nanoscale precipitation(inclusion)and grain ***,the ductilizing mechanism can be attributed to the enhanced inclusion sphericity and ameliorative coherency between the inclusion and matrix,and improved misorientation angle of grain boundary owing to the modification by Ce,which efficiently re-duced the stress concentration and enhanced cracking resistance during ***,doping rare earth elements presents a promising pathway to synergistically improve the strength and ductility of stainless steels by AM.
A noninvasive brain-computer interface is a central task in the comprehensive analysis and understanding of the brain and is an important challenge in international brain-science *** implanted brain-computer interface...
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A noninvasive brain-computer interface is a central task in the comprehensive analysis and understanding of the brain and is an important challenge in international brain-science *** implanted brain-computer interfaces are cranial and invasive,which considerably limits their *** development of new noninvasive reading and writing technologies will advance substantial innovations and breakthroughs in the field of brain-computer ***,we review the theory and development of the ultrasound brain functional imaging and its ***,we introduce latest advancements in ultrasound brain modulation and its applications in rodents,primates,and human;its mechanism and closed-loop ultrasound neuromodulation based on electroencephalograph are also ***,high-frequency acoustic noninvasive brain-computer interface is prospected based on ultrasound super-resolution imaging and acoustic tweezers.
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