Sensors for monitoring temperature, heat flux, and thermal radiation are essential for applications such as electronic skin. While pyroelectric and thermoelectric effects are suitable candidates as functional elements in such devices, both concepts show individual drawbacks in terms of zero equilibrium signals for pyroelectric materials and small or slow response of thermoelectric materials. Here, these drawbacks are overcome by introducing the concept of thermodiffusion‐assisted pyroelectrics, which combines and enhances the performance of pyroelectric and ionic thermoelectric materials. The presented integrated concept provides both rapid initial response upon heating and stable synergistically enhanced signals upon prolonged exposure to heat stimuli. Likewise, incorporation of plasmonic metasurfaces enables the concept to provide both rapid and stable signals for radiation‐induced heating. The performance of the concept and its working mechanism can be explained by ion–electron interactions at the interface between the pyroelectric and ionic thermoelectric materials. 相似文献
为了进一步推动国内含H_2S地下储气库的优化运行,以华北地区X地下储气库为例,为防止其运行过程中采出的天然气因含H_2S引发的安全问题,提出了有针对性的脱硫运行技术对策。主要包括:井筒抗硫技术、含硫气井井口失控远程点火技术和地面H_2S处理技术。地下选用国产宝钢生产的D114.3 mm BGT1气密封型防硫化氢螺纹油管及耐压强度达34.5 MPa的井下安全阀。对含硫井口配备失控远程点火系统。在地面主要采用"活性炭+脱硫剂"分层装填脱硫塔的方式实现采出混合气体脱硫,并结合储气库井受双向压力及井底热传导效应促进硫溶解。通过摸索并实施一系列针对性的技术对策,X储气库完全自主实现零事故安全运行,为类似地下储气库的建设及运行提供了一定的参考。 相似文献
Scanning probe lithography is used to directly pattern monolayer transition metal dichalcogenides (TMDs) without the use of a sacrificial resist. Using an atomic‐force microscope, a negatively biased tip is brought close to the TMD surface. By inducing a water bridge between the tip and the TMD surface, controllable oxidation is achieved at the sub‐100 nm resolution. The oxidized flake is then submerged into water for selective oxide removal which leads to controllable patterning. In addition, by changing the oxidation time, thickness tunable patterning of multilayer TMDs is demonstrated. This resist‐less process results in exposed edges, overcoming a barrier in traditional resist‐based lithography and dry etch where polymeric byproduct layers are often formed at the edges. By patterning monolayers into geometric patterns of different dimensions and measuring the effective carrier lifetime, the non‐radiative recombination velocity due to edge defects is extracted. Using this patterning technique, it is shown that selenide TMDs exhibit lower edge recombination velocity as compared to sulfide TMDs. The utility of scanning probe lithography towards understanding material‐dependent edge recombination losses without significantly normalizing edge behaviors due to heavy defect generation, while allowing for eventual exploration of edge passivation schemes is highlighted, which is of profound interest for nanoscale electronics and optoelectronics. 相似文献
Triple-negative breast cancer (TNBC) is one type of the most aggressive breast cancers with poor prognosis. It is of great urgency to develop new therapeutics for treating TNBC. Based on current treatment guideline and genetic information of TNBC, a combinational therapy platform integrating chemotherapy drugs and mRNA encoding tumor suppressor proteins may become an efficacious strategy. In this study, we developed paclitaxel amino lipid (PAL) derived nanoparticles (NPs) to incorporate both chemotherapy drugs and P53 mRNA. The PAL P53 mRNA NPs showed superior properties compared to Abraxane® and Lipusu® used in the clinic including high paclitaxel loading capacity (24 wt.%, calculated by paclitaxel in PAL), PAL encapsulation efficiency (94.7% ± 6.8%) and mRNA encapsulation efficiency (88.7% ± 0.7%). Meanwhile, these NPs displayed synergetic cytotoxicity of paclitaxel and P53 mRNA in cultured TNBC cells. More importantly, we demonstrated in vivo anti-tumor efficacy of PAL P53 mRNA NPs in an orthotopic TNBC mouse model. Overall, these chemotherapy drugs derived mRNA NPs provide a new platform to integrate chemotherapy and personalized medicine using tumor genetic information, and therefore represent a promising approach for TNBC treatment.
Flame spread over solid fuels in high‐pressure situations, such as nuclear containment shells during a pressurized period, has potential to result in catastrophic disaster, thus requiring further knowledge. This paper experimentally reveals the flame spread behaviors over fuel cylinders in high pressures. Polyethylene and polymethyl‐methacrylate cylinders with the diameter of 4.0 mm are used in this study. Ambient gas is air, and total pressures are varied from naturally normal pressure (100 kPa) to elevated pressure (500 kPa). Flame characteristics including flame appearance and flame size and burning rate and flame spread rate are investigated. Results show that in high pressure, the flame appearance is significantly affected. As the pressure increases, the blue flame disappeared, and the color of flame tip changes from luminous yellow to orange as well the orange part extends down towards the base of flame. The dimensionless flame height increases with pressure for pressure below 150 kPa and then decreases with pressure above that level. The burning rates show increasing trend with pressure and are proportional to P0.6 and P0.79 for polymethyl‐methacrylate and polyethylene, respectively. Besides, flame spread rates for polymethyl‐methacrylate and polyethylene both were found to be proportional to P0.5. 相似文献
In the present work Ba(Ti1-xCex)O3 ceramics are prepared through a standard solid-state sintering process. Crystal structures, dielectric properties, ferroelectric properties and electrocaloric... 相似文献