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Results show that the cathode supported tubular design may have future promise.
This method is useful for applications, such as field-emission lamps and x-ray tubes, which do not require nanofabricated cathode structures.
Proceedings ArticleDOI
Zhifei Wen, Rebecca Fahrig, Norbert J. Pelc 
05 Jun 2003
11 Citations
We conclude that fixed anode x-ray tubes can be used in a magnetic field although its desired electron optics must be fairly “straight” and the cathode-anode axis must be well aligned with the field.
This new kind of air-cathode, with a simple fabrication process, greatly reduced the energy consumption, cost and complexity of air-cathode fabrication.
Of all the display devices which have been so far proposed, the cathode ray tube still offers a number of advantages of its own: high luminous efficiency, easy addressing a wide dynamic range of brightness, and a well-established manufacturing process.
The tonal gradation of the picture which the tube produces is satisfactory when viewed on modern cathode-ray tubes.
This cold cathode is not only promising for pulse x-ray generation but also for the fabrication of sophisticated devices which require stable high current density operation.
This allows the implementation of almost every cathode material.
Journal ArticleDOI
C. C. Lauritsen, Benedict Cassen 
01 Sep 1930-Physical Review
6 Citations
The tube has been equipped with a hot cathode and a tungsten target, thus rendering it more suitable for spectrographic work.
The unique combination of efficient cathode emission and hot injection possible in these devices suggests that a solid state analogue of the cathode ray tube may be realizable.

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Is nickel better for electroplating than zinc?
5 answers
Nickel is not necessarily better than zinc for electroplating, as both metals have their advantages depending on the specific application. Nickel impurities in zinc electrodeposition hinder the process by generating hydrogen bubbles, reducing useful current, and affecting the purity of the produced zinc. On the other hand, zinc-nickel alloy coatings exhibit enhanced corrosion resistance and microhardness compared to pure zinc coatings, with a significant decrease in corrosion rate and improved structural properties. Additionally, the electrodeposition of Zn-Ni alloy films from specific baths can result in coatings with superior properties, such as lower dissolution rates, better corrosion resistance, and improved microhardness. Therefore, the choice between nickel and zinc for electroplating depends on the desired characteristics of the final product.
Definition of reduce Graphene Oxide?
4 answers
Reduced Graphene Oxide (rGO) is a material obtained through the reduction of Graphene Oxide (GO), which is typically produced from graphite oxidation processes. Various methods, such as chemical exfoliation and controlled reduction, are employed to reduce GO to rGO. rGO exhibits attractive properties for optoelectronic applications, with potential for mass production at a lower cost. One method involves suspending GO in a liquid medium with iodide, partially reducing it, and further reducing it through UV irradiation to obtain rGO. The preparation method for rGO involves simultaneous reduction and activation processes, increasing the interlayer distance and specific surface area compared to conventional methods. Overall, rGO offers tunable properties, high transparency, and conductivity, making it a promising material for various applications.
How does computer simulation contribute to the understanding of carbonization and graphitization processes in coal?
5 answers
Computer simulations play a crucial role in enhancing the understanding of carbonization and graphitization processes in coal. By utilizing numerical methods, such as those proposed in MATLAB-based models for coke oven heat transfer, researchers can simulate the complex thermal behaviors during carbonization. Molecular dynamics simulations, as seen in laser-induced graphitization studies, provide insights into the structural transformations at the atomic level during heating and cooling processes. Additionally, high-temperature thermal simulation experimentsand numerical investigations on coal swelling during carbonizationoffer valuable data on the evolution of graphite lattice structures and the physical changes coal undergoes under different conditions. These simulations help in predicting behavior, optimizing processes, and advancing knowledge of coal transformation mechanisms.
How does the chemical composition of Nb2O5 affect the redox properties of a GCE modified electrode?
5 answers
The chemical composition of Nb2O5 significantly influences the redox properties of a GCE modified electrode. Different studies have explored the synthesis and modification of Nb2O5 to enhance its electrochemical performance. For instance, the synthesis of Nb2O5/rGO composites has shown improved specific capacitance and electron transfer compared to rGO alone. Additionally, in situ doping of alkali metals in Nb2O5 has demonstrated a twofold enhancement in photoelectrochemical water splitting efficiencies, indicating improved charge carrier density and surface charge transfer. Moreover, Nb2O5/graphene nanocomposites have exhibited superior electrochemical conductivity and cyclic stability, making them effective electrodes for supercapacitor applications. These findings collectively highlight the crucial role of Nb2O5 chemical composition in enhancing the redox properties of GCE modified electrodes.
Why do thermal conductivities in a lithium battery go in different directions?
4 answers
Thermal conductivities in lithium batteries exhibit different behaviors due to various factors highlighted in the research. Single-crystal LiCoO2 displays strong anisotropy, temperature dependence, and size effects, resulting in high thermal conductivities, while polycrystalline LiCoO2 is more isotropic with lower thermal conductivities due to random grain orientations and grain boundary thermal resistance. Battery aging affects the through-plane thermal conductivity, with reduced state of health leading to a linear decline of up to -40%, impacting thermal management system design. Changes in thermal conductivity during charge-discharge cycles are linked to volume changes, formation of low conductivity compounds, and interface resistance, affecting heat transfer and ionic transport in the cathode. These insights emphasize the importance of understanding thermal transport processes for effective battery design and thermal management.
How vertically oriented nanotubes grow on aluminum foil?
4 answers
Vertically aligned carbon nanotubes (VA-CNTs) can be grown on aluminum foil through various methods. One approach involves synthesizing VA-CNTs on Al foil using the Floating Catalyst Chemical Vapor Deposition (FCCVD) method at 610 °C, with ethanol as the carbon source and ferrocene as the catalyst. Another method is the Aerosol-Assisted Catalytic Chemical Vapour Deposition (CCVD) process, which utilizes acetylene as the carbon source and ferrocene as the catalyst precursor, operating at 615 °C to obtain dense forests of VACNTs on Al foil. Additionally, VA-CNTs can be grown from Langmuir–Blodgett (LB) films with accumulated nanoparticles, showing different growth rates based on the size of the catalyst nanoparticles and the catalyst area ratio. These methods demonstrate the feasibility of growing vertically oriented nanotubes on aluminum foil for various applications.
What kind of componentes are from argyrodite electrolyte expose to air?
4 answers
When argyrodite electrolytes are exposed to air, they face challenges related to air stability and performance degradation. These components are known to suffer from issues such as decreased ionic conductivity, generation of toxic gases like H2S, and structural instability when exposed to moisture in the air. To address these concerns, researchers have explored various strategies, including the addition of excess iodine, Bi and O co-doping, and modification of chalcogen chemistry. These modifications have led to improved air stability, enhanced ionic conductivity, and better compatibility with lithium anodes and high-voltage cathodes. The advancements in argyrodite electrolytes aim to overcome the challenges associated with exposure to air, making them more suitable for practical applications in solid-state batteries.
What kind of components are from argyrodite electrolyte expose to air?
5 answers
When argyrodite electrolytes are exposed to air, the components such as iodine, bismuth, oxygen, and chlorine play crucial roles in enhancing the stability and performance of the solid electrolytes. Iodine is added in excess to improve air stability and electrochemical performance, resulting in higher ionic conductivity and lower activation energy. Bismuth and oxygen co-doping in argyrodite electrolytes lead to ultrahigh ionic conductivity and excellent air stability, with the formation of Li-Bi alloy aiding in reducing Li+ diffusion energy barriers. Modification of chalcogen chemistry in argyrodite sulfides results in improved electrochemical compatibility with electrodes, stability to oxygen and humidity, and the formation of beneficial electrolyte-electrode interphases. These components collectively contribute to the enhanced stability and performance of argyrodite electrolytes when exposed to air.
What is the most available spent Lithium ion battery type EV market?
5 answers
The most available spent Lithium-ion battery type in the electric vehicle (EV) market is lithium cobalt oxide (LiCoO2) cathode material, as indicated by the characterization of 40 samples of spent LIBs. While various cathode materials like LiFePO4 (LFP), LiCoO2 (LCO), and LiNixCoyMn1-x-yO2 (NCM) dominate the market, the demand for LiMn2O4 (LMO) cathode batteries is increasing, enhancing the recycling value of LMO batteries. Additionally, spent Li-ion batteries (SLIBs) are estimated to reach 125 million tons by 2030, emphasizing the importance of sustainable recycling strategies for both cathode and anode materials. Effective end-of-use management through refurbishing and material recovery is crucial for sustainable development and circular economy principles in the battery industry.
How does hcl help doping and affect morphology in NMC syntheis?
5 answers
HCl plays a crucial role in doping and morphology control during NMC synthesis. In the context of silicon nanowires, the introduction of HCl during doping significantly improves surface morphology, resulting in smoother surfaces and reduced tapering. Similarly, in polyaniline thin films, HCl doping influences morphology, with SEM showing irregular granular structures. Furthermore, in NMC cathode materials, elemental doping with lithium halide salts, such as LiBr or LiCl, enhances capacity retention and rate performance by affecting cathode porosity and surface morphology. These findings highlight the importance of HCl in doping processes, showcasing its impact on morphology and performance improvements in various material systems.
How does hcl help doping of transition metals and affect morphology in NMC syntheis?
5 answers
HCl plays a crucial role in doping transition metals and influencing morphology in various synthesis processes. In the context of NMC cathode materials, the addition of lithium halide salts, such as LiBr or LiCl, during calcination leads to effective doping with halogens like Br, Cl, or F, significantly impacting lithiation processes and cathode properties. Similarly, in the growth of silicon nanowires, the introduction of HCl during in situ doping results in improved surface morphology, reduced tapering, and enhanced dopant incorporation efficiency, leading to smoother surfaces and minimal wire diameter variations. Additionally, in the epitaxial growth of 4H-SiC, HCl-assisted growth enhances surface morphology and growth rates by facilitating silicon cluster etching, demonstrating the importance of HCl in morphology control during doping processes.