Large-field objective lens for multi-wavelength microscopy at mesoscale and submicron resolution

Conventional microscopes designed for submicron resolution in biological research are hindered by a limited field of view,typically around 1 mm.This restriction poses a challenge when attempting to simultaneously analyze various parts of a sample,such as different brain areas.In addition,conventional objective lenses struggle to perform consistently across the required range of wavelengths for brain imaging in vivo.Here we present a novel mesoscopic objective lens with an impressive field of view of 8 mm,a numerical aperture of 0.5,and a working wavelength range from 400 to 1000 nm.We achieved a resolution of 0.74μm in fluorescent beads imaging.The versatility of this lens was further demonstrated through high-quality images of mouse brain and kidney sections in a wide-field imaging system,a confocal laser scanning system,and a two-photon imaging system.This mesoscopic objective lens holds immense promise for advancing multi-wavelength imaging of large fields of view at high resolution.

Plasma jet array treatment to improve the hydrophobicity of contaminated HTV silicone rubber

An atmospheric-pressure plasma jet array specially designed for HTV silicone rubber treatment is reported in this paper. Stable plasma containing highly energetic active particles was uniformly generated in the plasma jet array. The discharge pattern was affected by the applied voltage. The divergence phenomenon was observed at low gas flow rate and abated when the flow rate increased.Temperature of the plasma plume is close to room temperature which makes it feasible for temperature-sensitive material treatment. Hydrophobicity of contaminated HTV silicone rubber was significantly improved after quick exposure of the plasma jet array, and the effective treatment area reached 120 mm？×？50 mm（length？×？width）. Reactive particles in the plasma accelerate accumulation of the hydrophobic molecules, namely low molecular weight silicone chains, on the contaminated surface, which result in a hydrophobicity improvement of the HTV silicone rubber.

Hydrophobicity changes of polluted silicone rubber introduced by spatial and dose distribution of plasma jet

The hydrophobicity of polluted silicone rubber was improved rapidly under plasma jet treatment.It is an important phenomenon of the interaction between the plasma jet and the porous surface,and shows a wide application prospect in the power system.In this process,the spatial characteristics and dose of plasma jet are very important.Therefore,the variation of hydrophobicity of polluted silicone rubber under plasma jet treatment was studied,and the spatial characteristics and dose of plasma jet on polluted silicone rubber were also investigated in the work.The results show that the surface property(hydrophilic or hydrophobic)depended on the dose of plasma applied to the surface.The effective treated area was a circle,and the contact angles changed along the radial direction of the circle.This was attributable to the diffusion of plasma bullets on the surface and the distribution of plasma species.The plasma dose could be characterized by the energy density of the plasma applied on the surface.With the increase of plasma dose,the surface contact angles first increased rapidly and then decreased gradually.

Dielectric barrier discharge-based defect engineering method to assist flash sintering

Oxygen vacancy OV plays an important role in a flash sintering (FS) process. In defect engineering, the methods of creating oxygen vacancy defects include doping, heating, and etching, and all of them often have complex processes or equipment. In this study, we used dielectric barrier discharge (DBD) as a new defect engineering technology to increase oxygen vacancy concentrations of green billets with different ceramics (ZnO, TiO_(2), and 3 mol% yttria-stabilized zirconia (3YSZ)). With an alternating current (AC) power supply of 10 kHz, low-temperature plasma was generated, and a specimen could be treated in different atmospheres. The effect of the DBD treatment was influenced by atmosphere, treatment time, and voltage amplitude of the power supply. After the DBD treatment, the oxygen vacancy defect concentration in ZnO samples increased significantly, and a resistance test showed that conductivity of the samples increased by 2–3 orders of magnitude. Moreover, the onset electric field (E) of ZnO FS decreased from 5.17 to 0.86 kV/cm at room temperature (RT);while in the whole FS, the max power dissipation decreased from 563.17 to 27.94 W. The defect concentration and conductivity of the green billets for TiO_(2) and 3YSZ were also changed by the DBD, and then the FS process was modified. It is a new technology to treat the green billet of ceramics in very short time, applicable to other ceramics, and beneficial to regulate the FS process.

Mode transition induced by back-breakdown of the gliding arc and its influence factors

Gliding arc is a mostly used non-equilibrium plasma generation method whose characteristic is affected by the backbreakdown phenomenon.Mode transition induced by back-breakdown of the gliding arc is studied in this work and effects of gas flow rate,applied voltage,electrode parameters on mode transition were studied.Experimental results show that there are two typical modes during the development of the gliding arc.Mode A comprises periodicitical development of the arc from the minimum gap breakdown to the longest extinguishment,while the arc in mode B continues to produce a back-breakdown at the ends of the electrodes.As the flow rate descends,the gliding arc gradually changes from mode A to B.It is the decrease of the arc velocity caused by lower flow rate leads to the occurrence of back-breakdown,which generates mode B.Smaller electrode opening angle,shorter length and wider minimum gap reduce the gliding speed,so that arc is more likely to enter mode B.As the applied voltage is increased,enhancing of the electric field strength on the breakdown path of the back-breakdown and thickening of the arc's diameter allow the gliding arc to enter mode B at a higher arc speed.

Interaction between plasma jet and silicone rubber covered by porous inorganic contaminants:Surface hydrophobicity or hydrophilicity?

The variation of surface hydrophobicity of silicone rubber materials covered with porous inorganic pollution layer under the action of atmospheric pressure plasma jet presents some new features,which have important engineering applications in the field of outdoor insulation of power systems.Interaction of the plasma with the polluted silicone rubber is studied and surface hydrophobicity is measured.Experimental results show that the exposure of plasma greatly accelerates the transfer of low molecular weight siloxanes(LMWs)in the pollution layer.However,the surface hydrophobicity is determined by the LMWs contents and the exposure time.Two acceleration effects of plasma during and after plasma exposure are proposed,their influence on surface hydrophobicity is analysed and related mechanisms are clarified.In addition,the competing influence of plasmainduced acceleration of the transfer of LMWs towards the surface and plasmaoxidation of LMWs on surface hydrophobicity is discussed.

Interfacial bonding enhancement of the RTV recoating with sandwiched contaminant by plasma jet

Room temperature vulcanised(RTV)silicone rubber is widely used in electrical power system,applied to the glass or porcelain insulator surface to enhance insulation.RTV coatings get contaminated after long-term operation and need to be recoated.Contaminants accumulate and embed into the surface of base RTV coating,forming a hard-to-remove inorganic transition layer.Such sandwiched contaminant layer destroys the adhesion between original and reapplied silicone rubber coating greatly.Authors’study innovatively reports a method to enhance interfacial bond properties of the RTV recoating with sandwiched contaminant layer,by using an atmospheric-pulsed discharge plasma jet(APPJ)for surface treatment.Water boiling test and 180-degree peel test were conducted to evaluate interfacial bond properties macroscopically.Scanning electron microscopy(SEM)was applied to observe the cross-section of recoating interface,while Fourier-transform infrared spectroscopy(FTIR)to detect chemical changes of contaminant layer,giving out microscopic and theoretical explanation.

A note on the collapsing geometry of hyperkahler four manifolds

We make some observations concerning the one-dimensional collapsing geometry of four-dimensional hyperk?hler metrics.