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Tumor oxygen spatial heterogeneity is a critical challenge for the photodynamic inhibition of solid tumors. Development of an intelligent nanoagent to initiate optimal therapeutics according to the localized oxygen levels is an effective settlement. Herein, we report an activatable nanoagent (BDP-Oxide nanoparticles (NPs)) to enable the oxygen auto-adaptive photodynamic/photothermal complementary treatment. Upon the nanoagent accumulated in the tumor region, the low extracellular pH could trigger the disassociation of the nanoagent to release the phototheranostic agent, BDP-Oxide, which will subsequently afford the fluorescence imaging-guided photodynamic oxidation after it gets into the outer oxygen-rich tumors. Along with the penetration deepening in the solid tumor, furthermore, BDP-Oxide could be reduced into BDP by the cytochrome P450 (CYP450) enzymes activated in the low oxygen tension regions of inner hypoxic tumors, which will switch on the photothermal and photoacoustic effects. Overall, the BDP-Oxide NPs-enabled photodynamic/photothermal complementary therapy significantly suppressed the solid tumor growth (inhibition rate of 94.8%). This work proposes an intelligent platform to address the oxygen partial pressure for the optimization of cancer phototherapeutics.

Here we investigate the aggregation behaviours of three prepared dyes in the liquid phase to pick out one possessing J-aggregation characteristic that is of significant interest for organic materials used in multiple bio-applications. The self-assembly of dyes usually leads to various forms of aggregates, for example, H-aggregates or J-aggregates and it is easy to distinguish bathochromic J-aggregation from hypsochromic H-aggregation using UV/vis light spectroscopy. Enlightened by the cyanine dyes that have shown a great tendency to self-associate, we designed and synthesized three cyanine dyes: Cy7-Ph, DCy7-Ph, and SN-Cy7-Ph, followed by the study of the influence of multiple factors on their aggregation behaviours, including solvent polarity, ionic strength, and temperature. Finally, we found that of the three molecules only SN-Cy7-Ph could self-assemble into J-aggregates conveniently and stably in the aqueous phase under normal conditions.

Granular flow has solid-, liquid-, or even gas-like behaviors, which can be described through discrete element method (DEM)-based simulations. Although the DEM simulation has advantages in studying particle-scale information, it is computationally intensive. Alternatively, this work proposes to combine the DEM and deep learning methods to predict granular flow behaviors in a wedge-shaped hopper. As the image-based labels are extracted from the DEM simulation, an Alexnet-fully connection (FC) model can make point-to-point predictions about the discharge time. Furthermore, when the first 20% of image-based datasets in the timing sequence are used to train a convolutional neural network (CNN)-long short-term memory (LSTM) network, it can make process predictions about the number ratio of remaining particles (NRRP) in the hopper vs. the discharge time. Although these attempts have some shortcomings at the present stage, more efforts are encouraged to stimulate the future potential of image-based prediction through the combined methods.

Porous membranes are one of the research hotspots in the domain of separation materials and have been widely utilized in various fields (such as water treatment, energy, biological medicine) due to their high separation efficiency, low cost, and non-secondary pollution, etc. However, there still exist many challenges in their application process, such as low selectivity, poor anti-fouling, poor responsive, critically limiting its development. Recently, bio-inspired porous membranes offer a brand-new idea for solving those problems and are becoming one of the most exciting research areas in porous membranes field. Compared with traditional porous membranes, bio-inspired porous membranes, designed by imitating the unique pore structure and separation performance of biological membranes, display distinct advantages in selectivity performance, antifouling property, intelligent gating property, and intelligent response property. This critical review detailedly presents the recent developments of bio-inspired porous membranes with multi-scale pore structure. In this paper, the first section mainly gives a brief introduction to the pore structure, separation selectivity, and response property of both nano-scale biological membranes and micro-scale biological membranes. Among numerous nano-scale biological membranes, the most concerning to date include cell membrane with ion channel, cell membrane with aquaporin, and glomerular filtration membrane. Ion channel embedded within cell membrane provides ion selectivity, ion current rectification, and ion gating characteristics to cell membrane. Inspired by this, novel porous membranes with excellent ion selectivity are developed for regulating ion permeation. Meanwhile, aquaporin can let the passive transport of water across cell membrane while simultaneously excluding ions, offering a new strategy for designing bio-inspired porous membrane for high efficiency desalination. Glomerular filtration membrane with the nano-scale pore can prevent the filtration of blood cells and platelets, and removes most of nano-scale molecules from the blood. Inspired by its unique filtration property, various bio-inspired porous membranes have been designed for clinical kidney replacement treatment. Additionally, the micro-scale porous membranes in nature mainly contain alveolar membrane with intelligent gating property and leaf stomata membrane with intelligent response property. By imitating the alveolar membrane, liquid gating porous membranes with intelligent gating property are developed, achieving for controlling the movement of fluids, vapours, and solids. Learning from leaf stomata membrane, intelligent responsive porous membranes are also designed, and can be applied in controllable transmission. For preparing the high performance of bio-inspired porous membranes, the designed strategies are also introduced in detail. The second section has further outlined the applications of bio-inspired porous membranes in water treatment, energy, biological medicine, and substance detection. In water treatment field, aquaporin-based bio-inspired porous membrane possesses better desalination performance than traditional porous membrane. In energy field, bio-inspired porous membranes offer unique ions selectivity and ions transport, thus enhancing energy conversion efficiency in salinity gradient energy capture. In biological medicine field, alveolar-like liquid gating composite membranes can be utilized for fabricating artificial blood vessel with anticoagulation and drug release properties. Moreover, bio-inspired porous membranes with porous support and thin separation layer are demonstrated as hemodialysis membranes for the treatment of kidney disease. In substance detection, visual and low power consuming chemical detection of specific analytes can be achieved by liquid gating composite membrane. In the last section, future challenges in theory, preparation technology, and application of bio-inspired porous membrane are presented, providing an overview of the various solutions. Ultimately, continued efforts to relative research and materials development will promote the rapid development of bio-inspired porous membrane.

The ignition characteristics of vaporized RP-3 kerosene were experimentally investigated in a cavity-based Mach 2.52 scramjet combustor. The simulated flight condition was Ma 5.5 at 25 km, while the entrance had a stagnation temperature of 1486 K and a total pressure of 1.6 MPa. With high-speed photography and chamber pressure measurement, the effects of fuel temperature on ignition performance were studied under a lean fuel condition, and the mechanism of ignition failure during the fuel temperature increasing was investigated. The results showed that increasing the injection temperature could accelerate the atomization and evaporation processes of the fuel droplets, reduce the ignition delay time, and enhance combustion in the cavity. However, a critical point (about 567 K) was found in vaporized kerosene ignition. When the injection temperature approached this point, the phase of the kerosene jet transited sharply, and the penetration depth increased. It decreased the fuel-air equivalence ratio in the cavity, deteriorating the reaction environment and causing ignition failure. The blow-out process had a similar evolution at different injection temperatures. Flame in-cavity was repeatedly stretched and merged with dissipating heat, and eventually blown off near the bottom. The flame residence time was closely related to the discharge time of the spark plug.

The ignition limits of liquid kerosene injected upstream of a cavity flameholder using a spark plug are investigated in a model scramjet combustor with the isolator entrance Mach number of 2.52, the total pressure of 1.6 MPa, and stagnation temperature of 1486 K. The effects of injection pressure and mixing distance on ignition are studied. Flame dynamics and the evolution of the flow field during the ignition process are acquired through high-speed photography and Schlieren photography. For near-field injection, successful ignition of kerosene can only be achieved when the injection pressure is extremely low or in a higher injection pressure range. The ignition is failed due to the fuel-rich local equivalence ratio in the cavity recirculation zone when the injection pressure is in the middle of injection pressure range. For far-field injection, the ignition trend is totally opposite compared with near-field injection. The ratio of the fuel that the cavity can react completely to that consumed by the mainstream is extremely low due to the minimal mass exchange rate between the cavity and the mainstream. The local equivalence ratio in cavity is the controlling factor determining whether successful ignition could be achieved. Only local ignition with low combustion efficiency is achieved in the present single-cavity combustor. The flame could not spread to the mainstream due to the lower turbulence level weakening the interaction of combustion products in the recirculation zone with unburned reactants in the supersonic flow.

The level of clotting protein ‘factor IX’ (FIX) is highly associated with cerebral ischemia, and this research work has developed a sensitive detection of FIX on dielectrode sensor by current-volt measurement. Sensing area was grown with zinc oxide nanowire to attach more probe for FIX interaction. Aptamer was utilized as the detection probe and attached on the sensing electrode surface through amine-aldehyde chemical linkage. In addition, biotin-streptavidin interaction was utilized to attach the higher number aptamers on the electrode surface connected with dual-probe station. FIX detection limit was found as 10 fM in the phosphate buffer saline spiked samples and 1:320 dilution of human serum. The linear ranges were as 10 fM to 100 pM and 1:320 to 1:80, respectively. With a good determination co-efficient [y = 2.6813x − 3.8467; R(2) = 0.9479] this biosensing strategy helps to quantify FIX and monitor the condition of cerebral ischemia.

Developing single molecule-assembled nanoprodrugs that can reverse the glutathione (GSH)-mediated drug resistance of tumors provides promising potentials for precision and effective cancer theranostics. Herein, we developed a novel single molecule-assembled nanoprodrug for effective photodynamic/chemotherapeutic eradication of drug-resistant tumors via the multistage GSH-depletion. The nanoprodrug MSSP-NP could be fancily fabricated by self-assembly of an amphiphilic activatable molecular MSSP, which is synthesized by covalently conjugating the photosensitizer methylene blue (MB) with a GSH-sensitive cisplatin prodrug via a tumor targeting thiolated polypeptide. Upon the nanoprodrug MSSP-NP systematic administrated, its photoactivities and pharmacological effects can be thoroughly switched on by intracellular GSH to produce the photosensitizer MB and chemotherapeutic drug cisplatin, along with the multi-step consumption of GSH, which could remarkably boost oxidative stress and reverse the drug resistance. As a result, the nanoprodrug could effectively disrupt the tumor GSH-defense system to afford high-efficiency photodynamic/chemotherapeutic inhibition of drug resistance tumors (96.4%) with minimum side effects.

Upconversion nanoparticles (UCNPs) based phototheranostics offer significant expectations for the personalized cancer medicine via integrating both modalities of imaging diagnostics and phototherapeutics. However, programmably controlling the photoactivation of imaging and therapy towards the accurate diagnosis with minimum side effects for on-demand therapy has remained challenging due to the lack of ideal switchable UCNPs agents. Herein, we demonstrate a facile strategy to simply switch the near infrared emission at 800 nm from rationally designed UCNPs by modulating the irradiation laser into pulse output. Through synthesis of the theranostic UCNPs-DI agent combining with a photosensitizer and a photoabsorbing agent assembled on the UCNPs, the orthogonal activation of in vivo photoacoustic imaging and photodynamic therapy was further achieved by simply altering the excitation modes from pulse to continuous-wave output upon a single 980-nm laser. Importantly, no obvious harmful effects during photoexcitation caused by reactive oxygen species (ROS) photooxidation and photohyperthermia were generated under imaging modality, which facilitates the long-term and real-time imaging-guidance for the subsequent phototherapy. This work provides a new facile approach for the orthogonal activation of imaging diagnostics and photodynamic therapeutics towards the target cancers.

Phototheranostics based on upconversion nanoparticles (UCNPs) offer the integration of imaging diagnostics and phototherapeutics. However, the programmable control of the photoactivation of imaging and therapy with minimum side effects is challenging due to the lack of ideal switchable UCNPs agents. Here we demonstrate a facile strategy to switch the near infrared emission at 800 nm from rationally designed UCNPs by modulating the irradiation laser into pulse output. We further synthesize a theranostic nanoagent by combining with a photosensitizer and a photoabsorbing agent assembled on the UCNPs. The orthogonal activation of in vivo photoacoustic imaging and photodynamic therapy can be achieved by altering the excitation modes from pulse to continuous-wave output upon a single 980 nm laser. No obvious harmful effects during photoexcitation was identified, suggesting their use for long-term imaging-guidance and phototherapy. This work provides an approach to the orthogonal activation of imaging diagnostics and photodynamic therapeutics.

Polymeric materials with high thermal conductivity have drawn much attention in academic and industrial field recently. Due to poor dispersion and insufficient interconnection of fillers, traditional polymer composites present not only undesirable thermal conductivity but other declined properties even with high loaded thermal conductive nanofillers. In this work, the uniform and continuous network of (3-Aminopropyl)trimethoxysilane (APTMS) modified carbon nanotubes (A-CNTs) in poly(vinylidene fluoride) (PVDF) was built up by using the simple casting method. Thermal conductivity of 2.15 Wm−1K−1 and tensile strength enhancement of 70% are achieved at 40 vol% A-CNTs loading compared with that of pure PVDF. The A-CNTs/PVDF composites exhibit an intensified thermal stability and sharply increased crystallinity (45.7%) compared with pure PVDF (28.5%). Moreover, for practical heat exchange experiment, the PVDF composites possess high heat transfer efficiency and long-last stability in corrosive water, which leads to the use of PVDF materials to supersede metal materials in heat transfers.

The effects of cavity parameters on combustion oscillation inside an ethylene-fueled scramjet combustor equipped with a cavity flameholder are experimentally investigated for Mach 5.5 flight conditions. Three certain cases, such as i) longer length-to-depth ratio, ii) sharper aft degree of cavity, iii) closer air throttling downstream of the cavity, exhibit quasi-periodic combustion oscillation, which can be separately attributed to i) larger recirculation volume in the cavity and more mass and heat exchange between cavity shear layer and the core flow, ii) the stronger impinging shock wave in the cavity acting on shear layer, iii) improved fuel/air mixing owing to the interaction between separated boundary layer and combustion. High-speed and schlieren images demonstrate that the cavity and downstream of it act as the most sensitive areas, at the same time, the factors mentioned above can form a thermal throat further triggering flame flashback, which is an indispensable key sub-process of combustion oscillation. The quantitative analysis results obtained from iso-luminosity contour have shown the different distribution trends of flame front and distinct differences of quasi-periodic oscillation frequencies, whereas similar flame propagation speed distributions. In addition, a simplified combustion opening system model has been established to analyze combustion oscillation mechanisms, which theoretically demonstrates that above factors can destroy the balance of heat release and dissipation, causing the system cannot self-stabilize once certain temperature fluctuation thresholds in sensitive areas are exceeded.

Superhydrophobic/superoleophilic (SHBOI) porous materials have attracted significant interest in the field of oil/water separation, however, fabricating SHBOI porous materials though a low cost, one-step and simple strategy is still a great challenge. In this work, a facile approach is developed for scaling the production of SHBOI porous materials by the deposition of SHBIO PDMS-co-PMHS coating onto porous materials via a facile surface coating method without the use of nanoparticles and fluorinated compounds. Meanwhile, the PDMS-co-PMHS coating is constructed by hydrosilylation reaction between vinyl bonds of vinyl-terminated-poly(dimethylsiloxane) (VPDMS) and silicon-hydrogen bond of trimethylsilyl-terminated-poly-(dimethylsiloxane)-co-polymethylhydrosiloxane (TPDMS-co-PMHS), and simultaneously attached on various porous substrates including sponge (SP), fiber paper (FP), glass fiber (GF) membrane, etc. As a result, PDMS-co-PMHS coating provides SHBOI and excellent oil/water separation characteristics to the porous substrates. According to the results, PDMS-co-PMHS@SP possesses SHBOI characteristics, high oil-adsorption capacity (up to 143 times its original weight) and excellent recyclability. PDMS-co-PMHS@FP can efficiently separate a series of immiscible oil/water mixtures in a single-step based on its high oil or organic solvents fluxes (about 2000–3000 L.m−2.h−1) and SHBOI characteristics. In addition, PDMS-co-PMHS@GF membrane exhibits great water rejection (∼99.90%) for separating water-in-oil emulsions under gravity-driven condition. Thus, a new strategy employing PDMS-co-PMHS as a coating material to modify porous substrates has great potential for developing a scalable method of fabricating SHBOI porous materials for oil/water separation.

The ignition processes of single-point laser ignition (LI) and dual-point LI were experimentally investigated in a cavity-based Mach 2.52 scramjet combustor fueled with ethylene. The stagnation temperature and total pressure of the supersonic inflow were 1486 K and 1.6 MPa, respectively. The results indicate that the ignition performance of dual-point LI with a plasma distance of 3 mm is the same as the single-point LI. However, further increasing the plasma distance to 7 mm degrades the ignition performance of dual-point LI. Therefore, dual-point LI is not superior to single-point LI in the scramjet combustor, which is contradictory to the investigations performed in quiescent premixed combustible mixtures. The reason is that the high turbulence intensity and strain rate in the cavity recirculation flow (∼100 m/s) lead to serious plasma and flame quenching instead of enhancing the flame propagation. Therefore, expanding the spatial distribution of the plasma by dual-point LI method, which might result in significant radical loss and heat loss, is not recommended for igniting a scramjet combustor.

Membrane distillation, which can utilize low grade energy, has attracted significant attention recently. However, membrane fouling is a big issue impeding its development and industrialization. Hence, it is essential to prepare amphiphobic membrane for comprehensive anti-fouling performance. Herein, a facile and biomimetic method is explored to design amphiphobic surface with special structure and controllable wettability. Commercial polyvinylidene fluoride (PVDF) was primarily functionalized with polydopamine (PDA) coatings and then nanoscale roughness was introduced on the membrane surface, followed by the fluorination of 1H,1H,2H,2H-perfluorodecanethiol. It is revealed that the amphiphobic property can be accurately controlled by controlling the dosage of Ag+. When the concentration of Ag+ is 300 mM, the water and oil contact angle of the optimal membrane can achieve 167.6 ± 0.27° and 136.9 ± 0.4°, respectively, while the water sliding angle is only 3 ± 0.1°, which demonstrates prominent superhydrophobicity and oleophobicity. Furthermore, the amphiphobic membrane exhibits excellent chemical and thermal stability under harsh conditions as well as outstanding comprehensive anti-fouling capacity with higher flux and excellent salt rejection in the long-term direct contact membrane distillation (DCMD) experiments, which shows promising potentials for application in the field of membrane distillation.

Polymer-based materials with high thermal conductivity are highly desirable for thermal management applications. In this work, a new hierarchical three-dimensional (3D) framework is built by electrostatic self-assembly between positively charged carbon nanotube (CNT) and negatively charged graphene oxide (GO) in poly(vinylidene fluoride) (PVDF). The obtained composites possess an enhanced thermal conductivity and outstanding mechanical properties simultaneously. Thermal conductivity enhancement of 628% and tensile strength enhancement of 120% are achieved at 10 wt% GO-A-CNT hybrid filler loading compared with that of pure PVDF. Moreover, the GO-A-CNT/PVDF composites exhibit mainly polar γ-form crystallites and sharply decreased crystallinity compared with pure PVDF and CNT/PVDF composites. The theoretical simulation of the effective medium theory is well fitted with experimental observation, which elucidates the significance of 3D framework for more efficient phonon transmit. These GO-A-CNT/PVDF composites may have great potential application as heat exchanger materials.

Network pruning can reduce the high computation cost of deep neural network (DNN) models. However, to maintain their accuracies, sparse models often carry randomly-distributed weights, leading to irregular computations. Consequently, sparse models cannot achieve meaningful speedup on commodity hardware (e.g., GPU) built for dense matrix computations. As such, prior works usually modify or design completely new sparsity-optimized architectures for exploiting sparsity. We propose an algorithm-software co-designed pruning method that achieves latency speedups on existing dense architectures. Our work builds upon the insight that the matrix multiplication generally breaks the large matrix into multiple smaller tiles for parallel execution. We propose a tiling-friendly "tile-wise" sparsity pattern, which maintains a regular pattern at the tile level for efficient execution but allows for irregular, arbitrary pruning at the global scale to maintain the high accuracy. We implement and evaluate the sparsity pattern on GPU tensor core, achieving a 1.95x speedup over the dense model., Comment: 12pages, ACM/IEEE Proceedings of the International Conference for High Performance Computing, Networking, Storage and Analysis (SC20)

The influence of injection parameters on combustion oscillation inside an ethylene-fueled scramjet combustor equipped with a cavity flameholder is experimentally investigated for Mach 5.5 flight conditions. Experiments focusing on the influence of the fuel equivalence ratio, the premixing distance, the injection angle, and the number of jets have been carried out. Under certain conditions, high-speed camera and schlieren images show that flame oscillation occurs between the fuel injectors and the leading edge of the cavity. It is also demonstrated that those factors mentioned above can significantly affect the flow-shock interaction which generates low flow speed region and the mixing status which correlates with combustion intensity closely. The strong interaction between combustion and the separated boundary layer downstream of the cavity forms a thermal throat inducing thermal chocking to cause flame flashback. The distributions of the flame front, flame propagation speeds and quasi-periodic oscillation frequencies obtained by the iso-luminosity contour method show distinct differences in different cases. The strong interactions of flow and shock, combustion and separated region can easily trigger flame flashback, and the flame front can be maintained around the injector for long time in cases of deeper penetration depth and longer premixing distance. A simplified combustion opening system model predicts that the flame under sensitive conditions may acquire an exponential amplification once thresholds of the thermal fluctuation are exceeded.

Thermal-conductive polymer composites have developed to be a hotspot in academic and industrial fields recently. Both efficient heat transport and superior mechanical properties are of critical significance for high-performance thermal-conductive devices. In this paper, magnetic hexagonal boron nitride (mhBN) with excellent interfacial compatibility is successfully synthesized by dopamine and magnetic co-functionalization, and mhBN-poly(vinylidene fluoride) (mhBN-PVDF) composites with a combination of high thermal conductivity and outstanding mechanical property are achieved due to the integration of excellent interfacial interaction and aligned filler architecture into one material's system. The thermal conductivity increases from 0.35 W/(m K) for the 20 wt % pure BN-PVDF to 0.82 W/(m K) after the dopamine modification and further to 1.43 W/(m K) after alignment. The effective medium approximation model demonstrates that the optimization of mhBN orientation and decrease of thermal resistance are two major factors for the enhancement of thermal conductivity. Moreover, the mhBN-PVDF composites also exhibit excellent tensile strength (168.5 MPa at 15 wt % content) and impact strength (20-30 kJ/m

Ignition and flame stability in supersonic flow have always been the key problems of research in scramjet. In addition, ignition is difficult and the cavity flameholder is susceptible to support the flame stability under extreme conditions such as low equivalent ratio. In recent years, gliding arc plasma is recognized to expand ignition and extinction limit with lower energy consumption in the field of plasma assisted ignition due to its heating and chemical effects. In this paper, a gliding arc igniter has been designed and compared with the traditional spark plug in order to quantify the ignition ability. The igniter has the same size with the spark plug, using low-power AC gliding arc to carry out ethylene ignition test in Ma = 2.52 Ma supersonic flow. The average power of gliding arc discharge is 1199 W. A high-speed camera and CH⁎ chemiluminescence were used to make combustion diagnosis. Founded in the same discharge period, the lean ignition limit of the gliding arc is lower than the ignition limit of the spark. The average expansion of ethylene ignition limit is 17%. The ignition process is that gliding arc continues to generate the initial flame kernels during the discharge period, but it is extinguished continuously due to the strong convection. Until generating an initial flame kernel which can successfully propagate the flame. The ignition process can be divided into four stages. It continues to generate new flame kernels in flame propagation process. Gliding arc reignites the fuel and generates the new flame kernels after forming a stable flame, appearing intermittent ignition in the cavity. The high equivalent ratio can make ignition delay time shorter, generating initial flame kernels more frequently. The heating effect of the gliding arc and reignition character make the thermal product and ethylene occur intermittent combustion more often in the cavity, increasing the area of the combustion reaction. Gliding arc plasma can achieve combustion enhancement during the flame stabilization process. The shear layer of flame thickness increased by the average of 2 mm on S-B-1 and G-B-1 conditions. Compared with the traditional spark ignition, gliding arc broaden the lean blow-off limit in different stages may be the significant reason for broadening lean ignition limit. It concludes that gliding arc makes the flame's ignition limit closer to the flame's blow-off limit.

Traditional polymer membranes suffer from low flux and oil fouling when utilized for separating oil/water emulsion. Herein, a novel and simple method is exploited to design a novel polymer composite membrane with superhydrophilic and underwater superoleophobic property for oil in water emulsion separation by depositing polydopamine (PDA) on hydrophobic polytetrafluoroethylene(PTFE) membrane surface in tetrahydrofuran (THF)-Tris buffer mixture. In comparison with the traditional PDA coating on hydrophobic membrane in a Tris buffer solution, a PDA layer with mass of hydrophilic carboxyl groups and nano-microspheres hierarchical structure is formed on hydrophobic PTFE membrane by PDA coating in a miscible THF-Tris buffer mixed solution, and endows PTFE membranes with excellent superhydrophilic and underwater superoleophobic property. Therefore, the as-prepared membranes can be applied in varieties of oil-in-water emulsions separation with ultrahigh permeate flux (above 2250 L/m2 h) under ultralow operating pressure (only 0.04 MPa) and excellent oil rejection. Finally, thanks to the low oil adhesion of the PDA layer, the resulting membranes display outstanding antifouling performance and reusability for oil water separation. On the whole, a novel rational methodology is provided to tailor PDA coatings with superhydrophilic and underwater superoleophobic property on hydrophobic membrane surface in tetrahydrofuran-Tris buffer mixture.

Dual-pulse laser-induced plasma ignition of kerosene in cavity at model scramjet engine is studied. The simulated flight condition is Ma 6 at 30 km, and the isolator entrance has a Mach number of 2.92, a total pressure of 2.6 MPa and a stagnation temperature of 1650 K. Two independent laser pulses at 532 nm with a pulse width of 10 ns, a diameter of 12 mm and a maximum energy of 300 mJ are focused into cavity for ignition. The flame structure and propagation during transient ignition processes are captured by simultaneous CH* and OH* chemiluminescence imaging. The entire ignition process of kerosene can be divided into five stages, which are referred as turbulent dissipation stage, quasi-stable state, combustion enhancement stage, reverting stage and combustion stabilization stage. A local closed loop of propagations of the burning mixtures from the shear layer into the recirculation zone of cavity is revealed, which the large-scale eddy in the shear layer plays a key role. The enhancement of mass exchange between shear layer and the recirculation zone of cavity could promote the flame propagation process and enhance the ignition capability as well as extend the ignition limits. A cavity shear-layer stabilized combustion of kerosene is established in the supersonic flow roughly 3.3 ms after the laser pulse. Chemical reactions mainly occur in the shear layer and the near-wall zone downstream of the cavity. The distribution of OH* is thicker than CH* at stable combustion condition.

This study presents a theoretical model that enables a fast and precise calculation of a sampled apodized fiber Bragg grating and the related sensor. Transfer matrix method was used since there is no analytical solution due to the complex refractive index profile. Errors brought by the uniform refractive index profile approximation were compensated, which allows a smaller number of divided segments and therefore a fast and memory efficient simulation. This compensation method realizes a high speed and high precision simulation. The theoretical spectra of both the grating and the sensor agrees well with those given by the experiments. According to the experiment, the sensitivity of the moisture sensor is −0.6165 pm/ppm in mineral oil. This theoretical model provides a new choice for the researchers and developers to design and optimize the sensing structure instead of a blind try and error process.