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Waste polyethylene terephthalate (PET) plastics were used as supports to fabricate Ag3PO4/UiO-66-NH2@PET (PAU-X) for adsorption and light-responsive desorption of sulfamethoxazole (SMX).

The vortex electromagnetic wave has attracted considerable attentions due to its theoretically infinite and orthogonal orbital angular momentum (OAM) mode characteristics. However, it is very diffi...

N-doped anatase-rutile titanium dioxide (N-TiO2) is a classical semiconductor widely used in environmental remediation. Its photocatalytic performance is typically affected by its morphology, porous structure, and phase composition. Herein, disk-like mesoporous N-TiO2 was prepared by calcining MIL-125(Ti) and melamine matrix at different temperatures in air. The photocatalytic efficiency of the prepared mesoporous N-TiO2 for the photo-oxidation of gaseous benzene under visible-light irradiation was studied. With respect to light absorption and mass transfer, as-prepared N-TiO2 annealed at 500 °C (MM-500) showed the best photocatalytic activity with corresponding photodegradation and mineralization efficiencies of 99.1% and 72.0%, respectively. In addition, MM-500 exhibited excellent reusability and stability in cyclic experiments, in which 84.8% of gaseous benzene could still be photodegraded after 10 experimental cycles. Furthermore, electron spin resonance analysis indicated that •OH and •O2− radicals were the dominating reactive oxygen species during the photo-oxidation process. Their excellent performance suggests that the as-prepared N-TiO2 photocatalysts can be used to eliminate volatile organic compounds.

Peripheral nerve injury (PNI) is a serious complication of trauma. Autologous nerve transplantation is the gold standard for the treatment of long-distance peripheral nerve defects, but is often limited by insufficient donor sites, postoperative pain, and paresthesia at the donor site. Peripheral nerve tissue engineering has led to the development of neural conduits to replace autologous nerve grafts. This study aimed to evaluate a new type of electrospun nanomaterial neural conduit, enriched with tacrolimus (FK506), which is an FDA-approved immunosuppressant, for the repair of long-distance peripheral nerve injuries. Poly (lactic-co-glycolic acid) (PLGA) nanofibrous films, with FK506, were prepared by electrostatic spinning and rolled into hollow cylindrical nerve vessels with an inner diameter of 1 mm and length of 15 mm. Material characterization, mechanical testing, degradation, drug release, cytotoxicity, cell proliferation, and migration assays were performed in vitro. Long-distance sciatic nerve injuries in rats were repaired in vivo using electrospun nerve conduit bridging, and nerve regeneration and muscle and motor function recovery were evaluated by gait analysis, electrophysiology, and neuromuscular histology. Compared to PLGA, the PLGA/FK506 nanomaterial neural conduit showed little change in morphology, mechanical properties, and chemical structure. In vitro, PLGA/FK506 showed lower cytotoxicity and better biocompatibility and effectively promoted the proliferation, adhesion, and migration of Schwann cells. In vivo, PLGA/FK506 had a better effect on sciatic nerve index, compound muscle action potential intensity and delay time, and nerve regeneration quality 12 weeks post-transplantation, effectively promoting long-distance defect sciatic nerve regeneration and functional recovery in rats. FK506-enriched PLGA nanomaterial neural conduits offer an effective method for repairing long-distance peripheral nerve injury and have potential clinical applications.

We report the generation of long plasma filament confined in a helium spiral vortex at atmospheric pressure. The discharge is produced by a dielectric barrier discharge setup and confined in the center of a spiral vortex. The length of the discharge can be several centimeters with flow rate less than 1 SLM. We find that the long filamentary discharge is the trajectory of fast-traveling plasma bursts and plasma plumes, where the plasma bursts are similar to the plasma jet produced at atmospheric pressure. The speeds of the downstream and upstream plasma bursts are about 46 000 and 95 000 m/s, respectively, which are affected by the spirally upward helium gas flow. Based on the novel design of vortex-confined discharge, we show that a plasma filament with a length of 10 cm can be produced.

A facile, rapid and environmental-friendly method was developed to prepare ZnO with different morphologies and superficial structures just using Zn(NO3)2 and hexamethylenetetramine (HMTA) as precursors by tuning nucleation rate. Rod-like ZnO-1 and ZnO-5, and irregular ZnO-10 and ZnO-20 were obtained as the amounts of the used reagents are 1, 5, 10 and 20 mmol, respectively. Compared to ZnO-1, the responses of ZnO-5, ZnO-10 and ZnO-20 toward ethanol were improved greatly, which could be attributed to their alternative active adsorbed oxygen species (O2−/O− for ZnO-5, ZnO-10 and ZnO-20, O2− for ZnO-1). It was proposed that the different active adsorbed oxygen species might result from the different activation of ethanol with the aid of ZnO. The response of ZnO-10 toward 50 ppm ethanol is 115, about five times higher than that of ZnO-1, and the best gas-sensing performance of ZnO-10 was deemed to result from its largest specific surface area and highest percentage of adsorbed oxygen.

A silver-based coordination polymer [Ag2(idca)(H2O)2] (BUC‑16), had been successfully prepared and used as efficient adsorbent to perform adsorption toward organic pollutants like promethazine hydrochlorine (PMH, 1395 mg g−1), sulfamethoxazole (SMX, 675 mg g−1), methylene blue (MB, 1317 mg g−1) in simulated wastewater. The slow-release of Ag+ ions from BUC-16 leads to its efficient and long-term antimicrobial and alga-inhibiting (odour control) activities. This is the first study on alga-inhibiting properties of coordination polymer, to the best of our knowledge. In vitro cytotoxicity (NIH-3T3 cells) test showed that BUC-16 has lower cell toxicity, implying its good biocompatibility.

Direct Z-scheme Bi5O7I/UiO-66-NH2 (denoted as BU-x) heterojunction photocatalysts were successfully constructed through ball-milling method. Photocatalytic activities of the as-prepared BU-x samples were determined by using a typical fluoroquinolone antibiotic, ciprofloxacin (CIP). All BU-x heterojunctions exhibited better CIP removal performances than that of pristine Bi5O7I and UiO-66-NH2 upon exposure to white light irradiation. In comparison, the heterojunction with UiO-66-NH2 content of 50 wt% (BU-5) showed excellent structural stability and the optimal adsorption-photodegradation efficiency for the CIP removal. The removal efficiency of CIP (10 mg/L) over BU-5 (0.75 g/L) achieved 96.1% within 120 min illumination. Meanwhile, the effect of photocatalyst dosage, pH and inorganic anions were systemically explored. Reactive species trapping experiments, electron spin resonance (ESR) signals, Mott-Schottky measurements and density functional theory (DFT) simulation revealed that the photo-generated holes (h+), hydroxyl radical (·OH) and superoxide radical (·O2–) played crucial roles in CIP degradation. This result can be ascribed to that the unique Z-scheme charge transfer configuration retained the excellent redox capacities of Bi5O7I and UiO-66-NH2. Meanwhile, the CIP degradation pathways and the toxicity of various intermediates were subsequently analyzed. This work provided a feasible idea for removing antibiotics by bismuth-rich bismuth oxyhalide/MOF-based heterostructured photocatalysts.

Series of MIL-100(Fe)/CoS composites (MxCy) were facilely fabricated using ball-milling method. The optimum M50C50 exhibited extremely higher Fenton-like catalytic degradation activity toward bisphenol A (BPA) than the pristine MIL-100(Fe) and CoS. The significant improvement of BPA degradation was attributed to the synergetic effect between MIL-100(Fe) and CoS with the synergistic factor being 95.7%, in which the Fe-S bonds formed at the interface of the two components facilitate the Fe3+/Fe2+ cycle by improving the electron mobility both from Co to Fe and from S to Fe. Furthermore, the influence factors like co-existing inorganic ions and pH values on the catalysis activity of M50C50 were explored. The possible reaction mechanism was proposed and confirmed by both active species capture tests and electron spin resonance (ESR) determinations. It was found that M50C50 demonstrated good reusability and water stability, in which the morphology and structure were not changed obviously after five runs' operation. To our best knowledge, it is the first work concerning the interfacial interaction of Fe-MOF/MSx to promote Fe3+/Fe2+ cycle in Fe-MOFs for the purpose of organic pollutants degradation in the Fenton-like AOPs system.

C-arm-image-assisted navigation systems for orthopedic surgery have been applied clinically for several years. Pedicle screw implantation is one of the important applications. A precise definition of a C-arm X-ray projection model is the key requirement for a C-arm-assisted navigation system. This study proposes using a high-pass filter to extract the contour of large markers of the image calibrator and an adaptive threshold method to segment images of small markers, thus improving the overall recognition rate of markers and enhancing the robustness of image calibration. A method for time synchronization of X-ray imaging and the detection of a patient’s lumbar position data for respiration compensation is also proposed. Positioning accuracy evaluation of the developed C-arm-assisted navigation system was carried out clinically. The results show that the mean positioning error is 2.409 mm and that the mean direction error is 1.449°.

We report that the response of the ferrofluid drop in the magnetic field can be described by the concept of a magnetic dipole. The gradient of the magnetic field in space is measured by the proposed model. Ferrofluid material not only exhibits the fluid property like surface tension and element transport but also can be manipulated by the magnetic field. A model is proposed that regards the bulk magnetization of the ferrofluid drop in the magnetic field as a magnetic dipole. The magnetic length coefficient denoting the ratio of the magnetic length of the dipole and the length of the major axis of the deformed drop is found scaling relation and is consistent with experimental results. A function is proposed that represents the responses of the deformation and traveling motion of the drop due to the presence of the magnetic field. The prolate-shaped traveling ferrofluid drops are demonstrated to measure the gradient of the magnetic field in space.

Two silver-based coordination polymers, [Ag2(O-IPA)(H2O)]·(H3O) (CP1) and [Ag2(bpe)2(Cl)2] (CP2), were facilely synthesized from AgNO3 and 5-hydroxyisophthalic acid (HO-H2IPA)/1,1′-(1,4-phenylene-bis(methylene))-bis(pyridine-3-carboxylic acid) (1pbb3ca) and 1,2-di(4-pyridyl)ethylene (bpe) by the slow evaporation method at room temperature. These two coordination polymers exhibited excellent and long-term antibacterial properties toward Gram-negative bacteria named Escherichia coli (E. coli), in which CP1 achieved the lowest minimum inhibitory concentration (MIC) of 5 ppm and largest inhibition zone of 11.12 mm due to its fastest Ag+ release rate and highest equilibrium concentration. These coordination polymers could destroy the membrane of the bacteria, leading to the death of cells. The stable and slow release of Ag+ ions in aqueous solutions for 5 d ensure the potentially further application in the purification of polluted water or medical purpose.

We report the evolution of multi-burst filamentary streamer discharge generated by a Tesla coil power in normal air. The multi-burst discharge shows a self-similar pattern from successive branching discharge. The upstream streamer is also observed in the experiment with a floating electrode. The trajectory of the streamer produced in the second wave packet follows the pathway of the streamer produced in the first wave packet. The expanding speeds of the second burst streamers are found to be faster than the speeds of the first burst streamers. We show that the second (and the following) burst streamer propagates inside the hot gas channel generated by the first (and the previous) burst streamer. The rotational temperature of the nitrogen molecules in the hot gas channel generated by the streamer in the first wave packet was measured by the optical spectrum method. By interrupting the hot gas channel, the presence of the hot gas channel is found to be crucial for the propagation of the following burst streamer.

In this study, the Bi24O31Br10 nanosheets were successfully synthesized using hydrothermal method. Subsequently, series binary BUC-21/Bi24O31Br10 composites were fabricated by facile ball-milling method. The results suggested that the introduction of a specific quality of Bi24O31Br10 on the surface of BUC-21 could enhance the utilization efficiency of white light and suppress the photo-induced carriers recombination to promote the photocatalytic efficiency. The BB-100 (the mass ratio of BUC-21/Bi24O31Br10 being 1) exhibited the best performance, in which 99.9% Cr(VI) ions were photoreduced into Cr(III) upon the white light irradiation within 120 min. As well, the influences of small organic acids, initial pH, light intensities along with the co-existing matters on the Cr(VI) removal were investigated. Furthermore, the Box-Behnken experimental design methodology proved that the photoreduction process was significantly influenced by the co-existing inorganic anions and negatively charged dissolved organic matters (DOM). After 4-run recycling for the adsorption-photoreduction of Cr(VI) experiments, the BB-100 still exhibited satisfied reduction activity with good stability and reusability. A possible reaction mechanism was proposed and clarified through the electrochemical determination, time-resolved photoluminescence decay spectra, active species trapping experiments, electron spin resonance analyses (ESR) and density functional theory (DFT) calculation.

Two silver-based coordination polymers, [Ag2(bpy)2(cbda)] (BUC-51) and [Ag3(bpy)3(cpda)]·(NO3)·9H2O (BUC-52), have been successfully prepared by slow evaporation at room temperature. These coordination polymers exhibited good adsorptive performances toward series organic dyes with sulfonic groups, which could be ascribed to the Ag cdots O interaction between the silver(I) atoms in CPs and the oxygen atoms from sulfonic groups attached to organic dyes. Both BUC-51 and BUC-52 favoured slow release of Ag+ ions resulting into outstanding long-term antibacterial abilities toward Gram-negative bacteria, Escherichia coli (E. coli), which was tested by a minimal inhibition concentration (MIC) benchmark and an inhibition zone testing method. Both scanning electron microscope (SEM) and transmission electron microscope (TEM) images demonstrated that these two Ag-based coordination polymers could destroy the bacterial membrane and further cause death. Additionally, the excellent stability in common solvents and good optical stability under UV–visible light facilitated their adsorptive and antibacterial applications.

The traveling and dancing behaviors of the bouncing drops on the oscillating liquid bath have been reported in several investigations. It was shown that the normal force during the impact of the drop on an inclined liquid surface is responsible for the traveling of a 0.8 mm-sized drop. Here, we report that a pair of vortexes can be induced by the repeated impact of a 2 mm-sized drop on an oscillatory liquid bath. The traveling of a large drop on the oscillatory liquid bath with an inclined bottom is found to be associated with the induced asymmetric vortex flow underneath the liquid surface. The effect of the vortex flow becomes significant for the size of a drop larger than 1.8 mm. Two-coupled drops with different sizes are found to be self-propelled on the oscillatory liquid bath with a flat bottom. The coupled drops propagate toward the direction of the small-sized drop. The distribution of the vortex flow is investigated by the particle image velocimetry (PIV) technique and the numerical simulation of the acoustic streaming model. PIV measurement and numerical simulation of the speed distribution of the vortex flows induced by the single bouncing drop and two-coupled drops show consistent results. It is suspected that the traveling of two-coupled drops is associated with the motion of the small drop and the liquid flow near the liquid surface.The traveling and dancing behaviors of the bouncing drops on the oscillating liquid bath have been reported in several investigations. It was shown that the normal force during the impact of the drop on an inclined liquid surface is responsible for the traveling of a 0.8 mm-sized drop. Here, we report that a pair of vortexes can be induced by the repeated impact of a 2 mm-sized drop on an oscillatory liquid bath. The traveling of a large drop on the oscillatory liquid bath with an inclined bottom is found to be associated with the induced asymmetric vortex flow underneath the liquid surface. The effect of the vortex flow becomes significant for the size of a drop larger than 1.8 mm. Two-coupled drops with different sizes are found to be self-propelled on the oscillatory liquid bath with a flat bottom. The coupled drops propagate toward the direction of the small-sized drop. The distribution of the vortex flow is investigated by the particle image velocimetry (PIV) technique and the numerical simulation of...

In our daily experience, the drops falling on a water pool usually immediately merge into water. The liquid drops floating at different environments are fascinating but attract less attention. Here, we report that the water drops are capable of floating on a water surface without heating, shearing, or oscillating the water pool. Water drops are generated from a beveled needle and fall on the clean water in an acrylic container. Water drops released from a beveled needle are found to travel on the water surface in a speed of tens of millimeter/second for several centimeters, which can be adjusted by the injection rate. A particle image velocimetry (PIV) technique is employed on the air, water drop, and water pool to confirm the rotation-induced shear effect for the delay coalescence. TiO2 particles and water aerosols served as visualized particles for PIV measurements in air, drop, and water pool. We show that the water drop can float on the water surface if it rotates or slides fast enough. The relative motion of the drop and the underneath surface plays an important role in the delay coalescence. The flow in the air layer between the drop and water pool not only shears the drop but also replenishes the loss of squeeze-out air in the thin layer.

We report the generation and evolution of a finger-shaped bubble in liquid by dielectric discharge setup. The spherical gas bubble is deformed into a finger-shaped bubble after the ignition of plasma. The presence of the filamentary discharge in the bubble not only provides the local heating to the bubble, it also changes the distribution of the electric field in the bubble and the bubble mutually provides the pathway to the discharge. The reduced surface tension on the liquid-gas interface due to the rise of temperature by plasma heating and the nonuniform electric field caused by the presence of filamentary discharge might induce the concave-shaped bubble. We also observe the formation of the quasi-two-dimensional bubble, which is generated from the bubble and attached on one side of the electrodes. It is found that the discharge induces the growth of the periodic fluctuations in the thin layer of gas.

The optical surface defects have a significant impact on functions and reliability of the whole optical system. In recent years, with the great attention on research of large-scale high-power solid-state laser device at home and abroad, the detection of optical surface defect has also been highly valued. Through continuous exploration, defect detection technology has made some achievements, but there are still some urgent technical problems to be solved. In this paper, the technology situation of optical surface defect will be summarized in two aspects: the surface cleanliness and surface flaws. Moreover, the technical difficulties and the problems which are currently facing will be analysis.

Inertial confinement fusion has been concerned in the year 1963. It was from the 1970s that China began to study inertial confinement fusion devices, and got lots of achievements in recent decades. The development of Inertial Confinement Fusion has an important and special meaning, whether to the national economy, military applications or for basic research. This paper comprehensively discussed the process of several large-scale ICF laser devices, the major technical indicators and the main experiment related to the devices.

We report on the observations of diffusion-limited aggregation-like patterns during the thin film removal process by an atmospheric plasma jet. The fractal patterns are found to have various structures like dense branching and tree-like patterns. The determination of surface morphology reveals that the footprints of discharge bursts are not as random as expected. We propose a diffusion-limited aggregation model with a few extra requirements by analogy with the experimental results, and thereby present the beauty of nature. We show that the model simulates not only the shapes of the patterns similar to the experimental observations, but also the growing sequences of fluctuating, oscillatory, and zigzag traces.

C-Arm image-assisted surgical navigation system has been broadly applied to spinal surgery. However, accurate path planning on the C-Arm AP-view image is difficult. This research studies 2D-3D image registration methods to obtain the optimum transformation matrix between C-Arm and CT image frames. Through the transformation matrix, the surgical path planned on preoperative CT images can be transformed and displayed on the C-Arm images for surgical guidance. The positions of surgical instruments will also be displayed on both CT and C-Arm in the real time. Five similarity measure methods of 2D-3D image registration including Normalized Cross-Correlation, Gradient Correlation, Pattern Intensity, Gradient Difference Correlation, and Mutual Information combined with three optimization methods including Powell’s method, Downhill simplex algorithm, and genetic algorithm are applied to evaluate their performance in converge range, efficiency, and accuracy. Experimental results show that the combination of Normalized Cross-Correlation measure method with Downhill simplex algorithm obtains maximum correlation and similarity in C-Arm and Digital Reconstructed Radiograph (DRR) images. Spine saw bones are used in the experiment to evaluate 2D-3D image registration accuracy. The average error in displacement is 0.22 mm. The success rate is approximately 90% and average registration time takes 16 seconds.

This work is inspired by the expansion of the plasma bubble in a narrow gap reported by Chu and Lee [Phys. Rev. Lett. 107, 225001 (2011)]. We report the unstable phenomena of the plasma-liquid interface with different curvature in a Hele-Shaw cell. Dielectric barrier discharge is produced in the cell at atmospheric pressure which is partially filled with silicone oil. We show that the Saffman-Taylor-like instability is observed on the bubble-type, channel-type, and drop-type interfaces. The Schlieren observation of the plasma-drop interaction reveals that there is a vapor layer around the drop and the particle image velocimetry shows the liquid flow inside the drop. We propose that the thermal Marangoni effect induced by the plasma heating is responsible for the unstable phenomena of the plasma-liquid interaction. The fluctuation of the interface is shown consistently with the Saffman-Taylor instability modified by the temperature-dependent velocity and surface tension.

The dusty plasma liquid formed by micro-meter sized particles negatively charged and suspended in a low pressure discharge background is a good candidate to study the generic spatio-temporal dynamical behaviors at the kinetic level through direct optical video-microscopy, because of the sub-mm interparticle spacing and the slow time scale. In this paper, starting from the basic picture of the avalanche type stick-slip cooperative hopping process under the interplay of mutual coupling and the stochastic thermal agitation, we briefly review our recent study on particle micro-motion and the associated structural rearrangement. The effect of mesoscopic confinement and external slow shear drive are also discussed., Comment: 12th International Congress on Plasma Physics, 25-29 October 2004, Nice (France)

We have investigated the behavior of bouncing drops on a liquid surface by using particle image velocimetry analysis. A drop on an oscillating liquid surface is observed to not coalesce with the liquid and to travel along the surface if the oscillation is strong enough. A streaming vortex pair, induced by the alternatively distorted liquid surface, shows up below a bouncing drop. The time-averaged flow fields of the vortices are measured. In our quasi-one-dimensional setup, there are three stable distances for the drops, which can be characterized by the Faraday wavelength. The interactions of the vortex-mediated bouncing drops are deduced from the streamlines in the liquid bulk. We further show that a three-dimensional vortex ring is induced by a bouncing drop in a square cell.

To investigate the distribution characteristics and correlation of inorganic element contents in Alismatis Rhizoma and rhizospheric soils from three habitats (Jianou, Fujian; Guangchang, Jiangxi; Pengshan, Sichuan).The inorganic element contents were detected with inductively coupled plasma mass spectrometry (ICP-MS).The results showed that inorganic element contents in Alismatis Rhizoma from different habitats presented regular distribution characteristics. In all samples, the contents of S, P, K, Mg and Ca were relatively high. The contents of S, P, K, Fe, Mg, Ca, Al and Zn in Alismatis Rhizoma from Fujian with low-content harmful heavy metal were more than those of other two places. Alismatis Rhizoma from different habitats showed remarkable ability to enrich P, S, Zn, Mg and Cu, especially to P and S. The contents of inorganic element in Alismatis Rhizoma and rhizosperic soil showed certain correlation.These results provide scientific evidence for artificial modification of effective components biosynthesis in Alisma orientalis, and it could also provide a reference for forming mechanism of genuine characteristics and quality of Alismatis Rhizoma.

We investigate the three-dimensional evolution of shock impact on a membraneless gas bubble. When a shock wave impacts a gas interface, gas layer is generally perturbed via the Richtmyer-Meshkov instability. We show the vortex structure evolves from the merging process of the extending spikes on the compressed D-shaped surface via the Richtmyer-Meshkov instability. The spikes are found to have a linear growth before 11 $\ensuremath{\mu}$s (of 1.4 mm). A ripple-typed fluctuating ring structure is observed and discussed with the scaling relation. We also notice that a thin layer exists in the intersection of the counterpropagating shock shells. The superposition of the rarefaction waves from both sides of the intersection is suspected to be responsible for the density change.

We investigate the evolution of the plasma bubble in a narrow gap. According to the morphological changes, we further show that there are three phases during the evolution for spherical fluctuating, radial fingering, and dense branching plasma bubbles, which are similar to the radial fingering pattern in a Hele-Shaw cell. The dependences of the wavelength of the fingering boundary are experimentally discussed. The dense branching plasma bubble is found with a fractal dimension of D(f)=1.74. The reduced surface tension pressure from the local heatings due to the filamentary discharges is suspected of being responsible for the growth of the radial fingering and the dense branching plasma bubbles.

The plasma bubble with dust particle depletion can be generated by a nano‐second laser pulse focused on one of the dust particles suspended in a strongly coupled dusty plasma liquid. The bubble dynamics at different time scales, including the initial forming and later traveling stages are investigated. In the first stage, dust particles are pushed outward by the outward ion flow associated with the plume generated by the more intensed plasma. The bubble then travels downward at a speed about 60 mm/s associated with a surrounding dipole‐like dust flow field. Two bubbles can also be simultaneously generated at different locations by separated laser pulses to study their interactions. Strong coupling is observed between two vertical bubbles. However, two horizontal bubbles are weakly coupled. The possible mechanism is discussed.

We review the recent studies on the micro‐dynamics in strongly coupled dust Coulomb liquids suspended in low pressure glow discharges. Under the interplay of stochastic thermal noise and Coulomb interaction, cooperative fast hopping strings and vortices excited from the small amplitude caged motion in the ordered lattice domains are the key cooperative excitations in the system. Their spatio‐temporal statistical behaviors obey the similar generic power law scaling as sac type avalanche in coupled sub‐excitable system under noise. The hopping can be further enhanced by the external stress and suppressed by the finite boundary. The liquid exhibits nonlinear viscoelastic response under high frequency AC shear drives and exhibits layering transition in a narrow gap down to a few molecular width. Travelling soliton‐type micro‐bubble can be formed through intense pulsed laser ablation.

Investigations of the structural arrangement of the atmospheric filamentary discharges were carried out. By observing the initial discharge events, we find that the surface charge plays a significant role of seeding electrons. The filamentary discharges show ordered and disordered patterns in parallel plates with different gap distances. A critical gap distance for an ordered pattern is found at about 700 μm. The transition of the order-disorder discharge pattern is also confirmed in a wedged-plates setup with a continuous change of gap distance. The bond-orientational function of the structure of the pattern is related to the mutual Coulomb interaction between discharges.

We investigate the wave-propelled phenomena of the drop on the oscillating flat surface and on the Faraday wave. With the quasi-one-dimensional setup, we observe the deformations of the oscillating oil surface and the gliding drop on the oil surface. The “glider” drop is found reaching the largest speed while system is driving at 65 Hz, which is consistent with the resonance of the drop and the oscillating surface. The distorted surface wave with different slopes is suspected of being responsible for the acceleration of the traveling drop. Furthermore, for drop traveling on the Faraday wave, the traveling speed is affected by the wavelength and the amplitude of the wave. The drops are found being trapped or slowed down around the nodes of the Faraday wave where the slopes are alternatively changed. The traveling speed of the drop is found decreasing linearly with the increase of the wave amplitude.

We report on the gap dependence of the planar atmospheric microplasma in air. We investigate the transitions of the dielectric barrier discharge in open air, including the random walk filaments (plasma columns), localized filaments, stochastic filaments, and diffuse discharge. A star-shaped filamentary discharge pattern is observed after the formation of the localized filaments. The liquid drops found on the dielectric surface further become a confining pattern for star-shaped discharge. We also demonstrate the applications of the insulating pattern for the use of the plasma display in open air by the handwritten characters with UV adhesive.

We investigate the evolution of laser-induced wavy vortex at 460 torr nitrogen gas environment. We show that Rayleigh–Taylor instability and Kelvin–Helmholtz instability are not the causes of the growth of the wavy vortex. Normal diffusion inducing the growth of the ripple-type perturbation is identified. The ratio of the perturbation amplitude to the wavelength of perturbation is found with 0.16. Through a quick estimation, measurements show the consistent scaling relations. We further show that the comatic aberration is suspected to be responsible for the asymmetric rarefaction wave, which triggers Kelvin–Helmholtz instability and induces the wavy vortex.

We investigate the evolution of the laser-induced breakdown of a suspended micrometer-sized carbon particle at 460 torr N2 gas environment. An elliptical hot gas resulting from the ionizations of the particle breakdown and the gas breakdown is observed. We show that the deformation of the elliptical gas starts from the vertical direction and the counterpropagating flows leads to a protruding tail at later stage. The rarefaction wave is suspected to be responsible for the deformation of the gas core and the formation of the vortex ring structure, which is different from the previous laser-induced gas breakdown investigations.

The drag force acting on a micron-sized polystyrene particle in the high Knudsen number regime is investigated. Analysis of the particle trajectories in stationary neutral argon gas environment suggests the damping time constant τ∝p−1.20±0.04 and Epstein drag force coefficient δ=1.40. The neutral drag coefficient is compared with the drag coefficient measurement in dust-free plasma. The phenomena of the reduced drag in weakly viscous and weakly ionized rf plasma are also observed in this report. It is shown that the slight changes in rf power and pressure would enhance the reduced drag effect, which suggests that there is an additional electrostatic force acting along the particle motion in the plasma.