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As a carbon-based flame retardant, carbon microspheres (CMS) not only block heat transfers at low temperature, but also the inert gas produced by its high-temperature decomposition can act as a dilution of combustible gases. However, its barrier effect is limited at high temperature. Herein, CMS were synthesized by a facial hydrothermal method with glucose as raw material. Then, a layer of molybdenum disulfide (MoS2) nanosheets was uniformly loaded on its surface to obtain a novel CMS@MoS2 hybrids with core-shell structure, which was used to improve the fire resistance of composite coating. The results showed that the backside temperature of the composite coating with 3% of CMS@MoS2 hybrids reached the lowest value (173.1 °C), revealing its highest heat shielding effect. Moreover, due to the improvement of the synergistic barrier effect of CMS and MoS2 nanosheets on gas and heat at high temperature, the EP/CMS@MoS2-3.0% coating exhibited the maximum expansion height (16.87 mm) and expansion rate (13.18). Meanwhile, the values of Tmax (372.9 °C) and carbon residue (30.6%) also reached the maximum, which is due to the catalytic carbon formation effect of Mo atom and the improvement of thermal and mass barrier performance of char layer. Moreover, smoke density tests showed that the EP/CMS@MoS2-3.0% had the lowest SDR (36.4%). Further, the EP/CMS@MoS2-3.0% exhibited the lowest PHRR (577 ± 13 kW/m2), THR (18.71 ± 0.9 MJ/m2), PSPR (0.118 ± 0.02 m2/m2) and TSP (2.80 ± 0.07 m2/m2) values, demonstrating its excellent flame retardant and smoke suppression properties.

In this study, the synergistic effect of carbon nanotubes (CNTs) and graphene oxide (GO) on the flame retardant properties of waterborne intumescent epoxy coatings was investigated. Firstly, bio-inspired polydopamine (PDA) was wrapped on the surface of CNTs to increase their water dispersibility and provide them with abundant reactive functional groups. Then, the 3-Aminopropyl triethoxysilane (KH550) was grafted on CNTs/PDA surface. Subsequently, the GO was combined with the modified CNTs by chemical reaction to obtain the GO@M-CNTs hybrids. The results showed that the composite coating with GO@M-CNTs hybrids had better fire retardant performance than the addition of CNTs or GO nanosheets alone. In contrast, the composite coating loaded with 1.5% of GO@M-CNTs hybrids exhibited the lowest backside temperature (168.2 °C), indicating its highest thermal insulation performance. Moreover, the results of the furnace storage experiments displayed that the GO@M-CNTs1.5%/EP sample exhibited the maximum expansion height (13.7 mm) and expansion rate (10.79) due to the hybrids effectively hindering the escape of the foamed gas into the air. In addition, the GO@M-CNTs1.5%/EP composite coating exhibited the maximum Tmax (370.4 °C) and char residue (28.8%) during the TGA test, which resulted in its most excellent fire retardant performance.

In-situ carbon-containing calcium aluminate cement (CCAC) was synthesized through carbon-bed sintering with calcium citrate tetrahydrate and Al2O3 as raw materials. The synthesized product was characterized by X-ray diffraction, field-emission scanning electron microscopy, high-resolution transmission electron microscopy, Raman spectroscopy, and infrared carbon–sulfur analysis. The results show that after sintering at 1500 °C for 4 h, the phase compositions of the product approached that of the commercial cement Secar71. The in-situ carbons in the product had partially graphitized domains and porous structures, were uniformly embedded in calcium aluminate, and the carbon content of the product was 1.45%. The floating ratios and oxidation ratios of the CCAC were lower than those of carbon back/Secar71 (S71CB) composite powders, implying that the water dispersion and oxidation resistance of CCAC were improved. Furthermore, the cold crushing strength (CCS), and cold modulus of rupture (CMOR) of the corundum-based castables bonded with CCAC, and S71CB, respectively, were compared. The CCS and CMOR values of the castables bonded with CCAC after being fired at 1100 °C for 3 h are higher by 20% and 21%, respectively, than those of the castables bonded with S71CB, suggesting that CCAC can be applied as a promising binder for the refractory castables.

We studied the explosive evaporation of high energy density matter generated by irradiation of intense heavy ion beams and the resulting effect on the dynamic vacuum of the accelerator beamlines. High Energy Density Physics (HEDP) experiments are proposed at the plasma physics terminal at the Facility of Antiproton and Ion Research (FAIR), which is currently under construction. The target response to irradiation by intense beam was simulated by HEIGHTS (High Energy Interaction with General Heterogeneous Target Systems) simulation package. The vacuum deterioration resulting from the target evaporation was simulated with the Molflow+ Monte-Carlo simulator. Experimentally we measured the pressure wave propagation at the HTD beamline at GSI in order to benchmark the simulation. The pressure wave was generated through ohmic heating of a cold surface.

By the way of hydrothermal reaction, the MoS2 nanoparticles were loaded on the surface of GO sheets uniformly. Then, the MoS2-RGO composites were modified with γ-(2,3-epoxypropoxy)propytrimethoxysilane (KH560), and followed by preparing the MoS2-RGO/epoxy composite coatings. The morphology and structure of MoS2-RGO were characterized though SEM, TEM, FT-IR and XPS. Besides, the corrosion resistance properties of the as-prepared MoS2-RGO/epoxy composite coatings were characterized by means of electrochemical impedance spectroscopy (EIS) and polarization curves analysis, and then the thermal stability and water permeability resistance of coatings were characterized. The results showed that the MoS2 could be loaded on the surface of GO uniformly when the ratio between MoS2 and GO is 1:1. The anti-corrosion property and permeability resistance of the MoS2-RGO/epoxy composites coating was enhanced significantly due to its excellent barrier property. Besides, the thermal property analysis exhibits that the lamellar structure of MoS2, GO and MoS2-RGO can effectively block the escape of the pyrolysis products, resulting in the maximum thermal weightlessness reduced.

Calcium aluminate with CaAl2O4 (CA) nanofiber structures was fabricated through a facile solid-phase combustion synthesis method with raw materials of CaO2, CaCO3, Al, and Al2O3 in Ar atomosphere at a pressure of 0.1 MPa. The results indicated that the relative content of CA decreased, but that of Ca12Al14O33 (C12A7) increased with the increase of r-value from 0 to 0.5 (r is molar substitution coefficient of CaCO3 for CaO2). Interestingly, CA nanofibers with tens of micrometers in length and about 200 nm in diameter were observed in the combustion products with r = 0.2, 0.3, 0.4, respectively. The more nanofibers can be found in the products, as the content of CaCO3 in raw material ratios increased. And the yield of nanofibers in the combustion product with r = 0.4 is the highest. The typical round droplet on head of nanofiber indicated that the growth process of nanofibers was governed by vapor-liquid-solid (VLS) mechanism with base growth mode. It is proposed that both higher reaction temperature and reducing atmosphere are requirements for the growth of CA nanofiber during the process of combustion synthesis. The nanofiber cannot be generated in the samples r0, and r5, because the gaseous Ca is absent due to oxidizing atmosphere and lower reaction temperature, respectively.

Kitchen waste oil (KWO) from catering industries or households was used as a low-cost carbon source for producing biosurfactants by self-isolated Pseudomonas aeruginosa. Fermentation performance with KWO was superior to those with four other carbon sources, with higher optical density (OD600) of 2.33 and lower interfacial tension of 0.57 mN/m. Culture conditions for biosurfactant production were optimized, with optimal pH of 8.0 and nitrogen source concentration of 2.0 g/L, respectively. The results of infrared spectroscopy and liquid chromatography-mass spectrometry (LC-MS) showed that the biosurfactant was a mixture of six rhamnolipid congeners, among which Rha-Rha-C10-C10 and Rha-C10-C10 were the main components, with mass fraction of approximately 34.20 and 50.86%, respectively. The critical micelle concentration (CMC) obtained was 55.87 mg/L. In addition, the rhamnolipids exhibited excellent tolerance to temperature (20–100 °C), pH (6.0–12.0), and salinity (2–20%; w/v) in a wide range, thereby showing good stability to extreme environmental conditions. The rhamnolipids positively affected oil removal from oil sludge and KWO-contaminated cotton cloth, with removal rate of 34.13 and of 30.92%, respectively. Our results demonstrated that biosurfactant production from KWO was promising, with advantages of good performance, low cost and environmental safety.

The research activities on warm dense matter driven by intense heavy ion beams at the new project High Intensity heavy-ion Accelerator Facility (HIAF) are presented. The ion beam parameters and the simulated accessible state of matter at HIAF are introduced, respectively. The progresses of the developed diagnostics for warm dense matter research including high energy electron radiography, multiple-channel pyrometer, in-situ energy loss and charge state of ion detector are briefly introduced. Keywords: Warm dense matter, Intense heavy ion beams, HIAF, Electron radiography, PACS Codes: 34.50.Bw, 94.20.Fg, 52.40.Mj, 87.59.B-, 41.75.Lx

This paper reports the measurement of the energy loss of protons at the energy of 100 keV penetrating a partially ionized hydrogen plasma. The plasma of ne≈ 1015–16cm−3; Te≈ 1–2 eV and lifetime of about 8 µs is created by the hydrogen gas discharge. The experimental results show an increase of a factor of 2.8 in the energy loss, which are in good agreement with the Bethe, Standard Stopping Model, Li–Petrasso and Vlasov models’ predictions within the error limit. The Bethe–Bloch Coulomb logarithm term is found to increase by a factor of 4.0 for free electrons as compared with the situation where bound electrons prevail. The potential application of protons energy loss for diagnosing the electron density in plasma is proposed too.

L-shell X-rays of 48Cd and 49In have been measured for the bombardment of protons in the energy range 75–250 keV in steps of 25 keV. The individual Lι, Lα, Lβ, Lγ and total L X-ray production cross sections were extracted from the yield. The results were compared with theoretical predictions of PWBA, ECPSSR and ECUSAR, as well as with experimental results of other authors. Good agreements were observed for our data with others and ECPSSR or ECUSAR calculations. The influence of using different atomic parameter databases is also discussed.

Optical hysteresis behavior (OHB) is of great importance for technological applications including optical data switching and manipulation. In this study, the power-dependent luminescent property of a single one-dimensional NaYbF4:X3+ (X = Er, Ho, and Tm) microcrystal was systematically investigated. We observed the interesting OHB that a system exhibits two different optical responses for the same laser input. A series of real colour luminescence patterns with information-rich upconversion cryptography were also obtained, which offers great opportunities for optical barcoding at the single particle level. The intrinsic OHB strongly depends on excitation approach, excitation power density range, Yb3+ concentration and sample crystallinity rather than active center. The underlying mechanisms of the intrinsic OHB and luminescence loss were explored, and a mechanism based on permanent local structural changes and intrinsic defect induced luminescence quenching is proposed. The laser thermal effect was confirmed by decreased luminescence intensity ratio of 2H11/2 → 4I15/2 to 4S3/2 → 4I15/2 transitions of Er3+ as the excitation power increased. The luminescent loss includes both irreversible and reversible processes, and these two processes can be distinguished via excitation power cycling experiments. Reversible luminescence loss contributed to defect quenching due to energy migration from Yb3+ to the native defects, and irreversible luminescence quenching originated from the thermally induced permanent local structural changes of microcrystals. This work not only enables a deeper understanding of power-dependent OHB in related systems, but also provides the new dimensions for special applications such as multilevel anti-counterfeiting and intelligent memory storage.

Probiotics, as novel functional foods via microbiota-modulation to enhance host health and inhibit tumor carcinogenesis, have been attracted considerable interests. L. casei JY, as a potential probiotic, was irradiated by 12C6+ beams and a new mutant strain JY300-8 was generated through three round selections of transit tolerance in the upper human gastrointestinal tract, adhesion ability to Caco-2 cells and inhibitory pathogenic microorganisms, respectively. Interestingly, JY300-8 presented excellent properties, including the strongest adhesion ability (86.81%) to Caco-2 cells to our knowledge and more excellent antimicrobial properties, which was used for the potential candidate probiotic. Additionally, JY300-8 could significantly inhibit the proliferation of Caco-2, HT29 and HCT116 cells in vitro, respectively. Furthermore, there were better therapeutic effects at an early stage in colon cancer mice, which included the similar survival rates (90%) and stronger inhibitory effect on tumor (83.48%), lower treatment cost and less side effects in comparison to the therapy drug (DFUR) for colon cancer (65.65%), which was attributed to promoting the apoptosis of colon cells and enhancing antitumor response via modulation cancer-induced gut microbiota dysbiosis by oral administration of JY300-8. Therefore, JY300-8 has great potential for bio-prophylactic and bio-therapeutic functional food in colon carcinogenesis. This work provided a promising approach that could improve human health, reduce greatly cancer incidence and mitigate cancer progression via modulation gut microbiota by excellent probiotics intervention.

An effective method to enhance the flame retardant capability of intumescent fire retardant (IFR) coatings by constructed a two-dimensional/two-dimensional (2D/2D) hybrid with good composition and microstructure. Herein, g-C3N4@PDA (CNP) was firstly obtained by loading graphite phase carbon nitride (g-C3N4) with bio-inspired polydopamine (PDA). Subsequently, a novel CNP@Mo hybrids was successfully prepared by loading molybdenum disulfide onto the CNP surface via a simple one-step hydrothermal method. Then, the obtained CNP@Mo was added to the IFR coating as a synergist to improve the flame resistance. Results indicated that the addition of 2 wt% CNP@Mo to the coating effectively accelerated the formation of the char layer and reinforced its thermal insulation properties. The CNP@Mo/EP sample exhibited the lowest backside temperature (179.6 ℃), the highest expansion ratio (10.53) and the most residual char (30.7%) by fire performance test, furnace test and TGA test. The combustion performance of the IFR coatings was investigated by cone calorimeter, and the results showed that the CNP@Mo hybrids based composite coating exhibited the lowest heat release rate (HRR), total heat release rate (THR), and total smoke production value (TSP). The mechanism investigations showed that the physical barrier effect and catalytic carbonization produced by CNP@Mo hybrids during the combustion process are the main reasons for the improved flame retardancy of epoxy coatings.

The influences of Cr2O3 on the viscosity of copper converter slag were investigated employing the rotating method in air atmosphere. The free running temperature was determined according to the viscosity-temperature curve and the activation energy was calculated based on Arrhenius-type relationship. The molten slag microstructure evolution was researched by Raman spectroscopy and Fourier Transform Infrared spectroscopy (FTIR). The results showed that the viscosity, free running temperature as well as activation energy increased significantly after the addition of Cr2O3. The viscosity of the original slag was 0.464 Pa·s at 1573K, exceeded 8.000 Pa·s after 5 wt% Cr2O3 being incorporated. Meanwhile, the Raman spectrums demonstrated that silicate network structure components of the molten slag samples converted from Q0 ([SiO4]4−, monomer) / Q1 ([Si2O7]6−, dimer) to Q2 ([SiO3]4−, chains) / Q3 ([Si2O5]2−, sheets), which indicated the formation of more complex structures and finally contributed to the increase of the viscosity. The influence mechanism of Cr2O3 on the copper converter slag viscosity and microstructures were uncovered to give reference for understanding the excellent slag resistance property of Cr2O3 containing refractories used in copper smelting furnaces.

Herein, the excellent properties of one dimension (1D) and two dimension (2D) nanoparticles were fully combined to enhance the thermal stability and flame retardancy of waterborne epoxy intumescent fire retardant (IFR) coatings. Specifically, layered hexagonal boron nitride (h-BN) nanosheet-linked acidified carbon nanotubes (CNTs) hybrids (BP@Si/CNTs) were prepared using polydopamine (PDA) and γ-(2,3-epoxypropoxy)propytrimethoxysilane (KH560) as bridging agents. The results of the fire test, furnace test and thermogravimetric analysis indicated that the incorporation of 2 wt% of BP@Si/CNTs hybrids in the IFR coating significantly improved the thermal stability and flame retardancy of the char layer. The backside temperature of the BP@Si/CNTs2.0%/EP sample decreased by 89.3 °C, the expansion rate increased by 11.53, and the residual char increased by 11.05 wt% compared to the control EP. The potential flame retardant mechanism was investigated by residual char analysis. The mechanism investigations indicated that the improved fire resistance of the composite coatings is attributed to the enhancement of the char layer by the physical barrier effect of the h-BN nanosheets and the "skeletal framework" effect of the CNTs during the combustion process.

Inspired by the multifunctional adhesion ability of poly dopamine (PDA), ZrO2 and aluminum magnesium hydroxide (LDH) were combined by PDA, which increased the function of this material in intumescent fire retardant (IFR) coatings. Briefly, PDA was coated on the surface of LDH to improve its dispersion stability in water. Then, the high thermal stability ZrO2 nanoparticles were immobilized in situ on the LDH/PDA surface to improve the strength and temperature resistance of the char layer by a hydrothermal strategy. The fire protection performance of LDH@PDA@ZrO2 (LPZ) modified intumescent fire retardant (IFR) coatings was performed by large plate method, thermogravimetric analysis (TGA) and furnace experiments. From the results, the IFR coating loaded with 2.5% LPZ exhibited the lowest backside temperature and the highest heat insulation, which reached 177.9 °C and 64.42, respectively. Besides, the coating exhibited the greatest expansion height (23.65 mm) and expansion rate (18.92), which is significantly higher than that of other coatings. Moreover, the maximum thermal degradation temperature (Tmax) and residual char of LPZ2.5%/EP were significantly higher than other samples. Further, the LPZ2.5%/EP based sample indicated the lowest smoke density rating (SDR) due to its excellent smoke suppression performance. The residual carbon analysis showed that ZrO2 nanoparticles and LDH nanosheets remained in the char layer during the combustion process, which is beneficial to increase the strength of the char layer and its barrier effect on heat and oxygen.

The mechanism of combustion synthesis (CS) for calcium aluminate was analyzed by a combustion front quenching method. The phase compositions of different zones in the quenched sample were examined by X-ray diffraction (XRD). The microstructural evolution during the CS process was explored by field-emission scanning electron microscopy equipped with energy dispersive spectrometer (FESEM-EDS). Moreover, the combustion temperature and wave velocity were measured. The results showed that the combustion reaction started with the decomposition of CaO 2 and melting of Al, at the same time, O 2 reacted with Al forming Al 2 O 3 , which released a large amount of heat to fuse CaO and Al 2 O 3 forming the liquid. Finally, calcium aluminates with good crystallinity would be gradually precipitated from the CaO-Al 2 O 3 liquid. Furthermore, a model corresponding to the dissolution-precipitation mechanism was proposed.

There has been an increasing growth in numerous applications that naturally generate large volumes of uncertain data. By the advent of such applications, the support of advanced analysis query processing such as the top-k and reverse top-k for uncertain big data has become important. In this paper, we model firstly probabilistic reverse top-k queries over uncertain big data for the discrete situation, in both monochromatic and bichromatic cases, denoted by MPRT and BPRT queries, respectively. We determine the partitions of solution space of MPRT queries and provide in theory a mathematical model for solving arbitrary dimensional data space. Additionally, we propose effective pruning heuristics to reduce the search space of BPRT queries. Moreover, efficient query procedures are presented seamlessly with integration of the proposed pruning strategies. Extensive experiments demonstrate the efficiency and effectiveness of our proposed approaches with various experimental settings.

To achieve high stability of foam extinguishing system, basalt(BAS) was first modified and added to form a three-phase foam system in this study. Firstly, the polydopamine(PDA) was coated on the surface of BAS. After that, the γ-(2,3-epoxypropoxy)propytrimethoxysilane(KH560) and (Octyl)-trimethoxysilane (OTMOS) were further grafted on the BAS surface to improve the dispersion and hydrophobicity. the modified results were verified by FT-IR, TG, and XRD. Secondly, factors including the surfactant type, concentration, temperature, and the mass concentration of solid particles were also studied. The results indicated that the foam performance of sodium dodecyl sulfate(SDS) was better than other surfactants. Within a certain range, the foam performance enhanced with the increasing stirring speed, time, and solid mass concentration. Moreover, the stability of the three-phase foam fire extinguishing agent added with modified BAS was significantly improved compared with the two-phase foam, and the 50% drainage time reached 28.03 mins, which was more than 4 times that of the two-phase foam. Hence, the optimized basalt eco-friendly three-phase foam is expected to play an effective application in the fire extinguishing and prevention of huge fires.

Graphene oxide-based membrane (GOM) has been massively studied in the dye/water separation field, predominately relying on their 1 nm-sized interlayer distance spacing (D-spacing). However, the inefficient removal of sub-nanosized dye molecules and swelling-induced weak long-term stability are currently two key challenges faced by GOM. In this work, we intercalate the soft polymeric polypyrrole (PPy) nanoparticles into GOM to address such gaps. The strong dye adsorption ability of PPy results in the increase of the sub-nanosized MB molecule rejection rate from 60% for GOM to 97% for GO-PPy membrane (GPM) after the initial filtration treatment. Simultaneously, the nanochannels of GPM are partially expanded, leading to an approximately a ~14 times water permeability (21.14 L m-2h−1 bar−1) improvement over GOM (1.56 L m-2h−1 bar−1). More importantly, the strong hydrogen-bond, electrostatic, and π-π interactions between GO and PPy improve the membrane mechanical stability and further reduce the D-spacing, while the enhanced separation ability of nano-sized dye molecules is also exhibited evidenced by the > 99% rejection rates of CV, EBT, CR, and TB. We consider that our strategy could promote the design and development of the high-performance GOM for nanofiltration applications.

Herein, polydopamine (PDA) with excellent hydrophilicity and strong adhesion was used to decorate the TiO2 nanoparticles. Then, the obtained PDA modified TiO2 was directly combined with graphene (Gr) through the π-π non covalent interaction to improve the water dispersion stability of hydrophobic Gr. After that, the above hybrids (TPG) was added to the intumescent waterborne epoxy coating to explore its fire protection ability. The fire resistance of the intumescent composite coating was tested by big panel method test, furnace test and thermogravimetric analysis (TGA). And the structure and morphology of the inorganic residual char were analyzed by FT-IR, XPS, SEM and XRD technology. The results showed that the introduction of PDA effectively improved the oxidation resistance of the composite coating, while TiO2 nanoparticles enhanced the stability of the char layer. More importantly, the incorporation of Gr further enhanced the barrier effect of char layer on thermal and mass. The 1.5 % TPG based sample exhibited the maximum expansion rate (8.61), the highest carbon residue (29.7 %) and the best heat insulation property due to the synergistic fire prevention effect of PDA, TiO2 and Gr nanosheets.

Waste paper, one of the major components of municipal and industrial wastes, has considerable potential as a low-cost inductive feedstock for enzyme production. In this study, four kinds of waste papers were used for simultaneous production of cellulase and xylanase by Trichoderma longiflorum. The highest FPase activities (3.21 IU/mL and 2.97 IU/mL) were achieved using waste office paper (WOP) and corrugated board (CB), respectively, followed by magazine paper (MP, 2.51 IU/mL) and tissue paper (TP, 2.34 IU/mL). The maximum β-glucosidase activities (0.51 IU/mL) and xylanase activities (382.59 IU/mL) were obtained from CB substrates, which were higher than that in the reported literature using waste paper. Correspondingly, the soluble protein concentrations and SDS-PAGE profiles from CB fermentation revealed that more enzymes were secreted during fermentation compared with other waste paper. Moreover, the structural features of different waste paper were characterized by using SEM and XRD technique and revealed that the structural variations were mainly caused by the raw wood sources and papermaking processes, and further affected the fermentation capacity. In addition, a higher β-glucosidase activity of 0.80 IU/mL were obtained from the mixed carbon source of CB and wheat bran (WB), which were significantly improved and increased by 56.86% when compared with the CB as single carbon source. This study confirmed that the waste paper without pretreatment could be efficiently utilized as an inductive feedstock for simultaneous production of cellulase and xylanase by T. longiflorum. Therefore, these findings obtained from this study will provide a more widely insight into investigating the low-cost inductive feedstock for enzyme production, which were of great benefit both for the economy and environment.

Firstly, the bio-inspired polydopamine (PDA) was coated on the surface of carbon nitride (CN), then used it (CNP) as nano-dispersant to improve the dispersion of graphene (Gr) in water on the basis of π-π interaction. After that, the KH560 was further grafted on the CNPG surface to improve the compatibility between inorganic hybrids and epoxy resin. The results of large plate experiments showed that the backside temperature of composite IFR coating containing CNPG@Si hybrids was significantly lower than that of other samples. Meanwhile, its expansion height after furnace test reached the maximum value (17.8 mm), which was greatly improved compared with the pure epoxy coating. Further, the maximum thermal decomposition temperature and the amount of char residue for the CNPG@Si/EP sample were significantly enhanced through the TGA test result. Besides, CNPG@Si based sample showed the lowest smoke density rating (SDR) due to its excellent smoke suppression performance. From the analysis of the morphology and composition of the char layer for CNPG@Si based sample, it can be seen that the introduction of Gr and CN increased the compactness of the char layer, and silicon network structures remained in the char layer after combustion, which effectively increases its strength and heat insulation effect.

L x rays of Nd have been measured for the bombardment of protons with the energies of 100–250 keV. It is found that Lγ 2 (abbreviation of Lγ 2,3,4,4 ′) x-ray emission is largely enhanced by proton impact, compared to the case of photon radiation. It is proposed that is caused by the multiple-ionization of outer-shell electrons. To verify this explanation, the enhancement for relative intensity ratio of Lι and Lβ 2 to Lα x ray and the energy shift of various L-subshell x rays are discussed. In addition, the production cross sections of Lι, Lα, Lβ and Lγ x ray are obtained and compared with theoretical calculations of PWBA, ECPSSR and ECUSAR, along with various atomic parameter databases.

A new project, High Intensity heavy ion Accelerator Facility (HIAF), is currently being under design and construction in China. HIAF will provide beams of stable and unstable heavy ions with high energies, high intensities and high quality. An overview of new opportunities for atomic physics using highly charged ions and radioactive heavy ions at HIAF is given.

Reverse top-k queries are proposed from the perspective of a product manufacturer, which are essential for manufacturers to assess the potential market. However, the existing approaches for reverse top-k queries are all based on the assumption that the underlying data are exact (or certain). Due to the intrinsic differences between uncertain and certain data, these methods cannot be applied to process uncertain data sets directly. Motivated by this, in this paper, we firstly model the probabilistic reverse top-k queries over uncertain data. Moreover, we formulate a probabilistic top-l influential query, that reports the l most influential objects having the largest impact factors, where the impact factor of an object is defined as the cardinality of its probabilistic reverse top-k query result set. We present effective pruning heuristics for speeding up the queries. Particularly, we exploit several properties of probabilistic threshold top-k queries and probabilistic skyline queries to reduce the search space of this problem. In addition, an upper bound of the potential users is estimated to reduce the cost of computing the probabilistic reverse top-k queries for the candidate objects. Finally, efficient query algorithms are presented seamlessly with integration of the proposed pruning strategies. Extensive experiments using both real-world and synthetic data sets demonstrate the efficiency and effectiveness of our proposed algorithms.

The hydrodynamic response of solid target heated by heavy ion beams at High Intensity Accelerator Facility (HIAF) project was simulated with 1-D computer code. The energy deposition was benchmarked by a 2-D program. The work serves to show the prospect of HIAF project for High Energy Density Physics (HEDP) study, and provide helpful information for the future experiments. Various target materials and schemes are used in the calculation. The results show that in the first phase of HIAF project, the available ion beam is already a powerful tool to generate HED matter with specially designed target, and the second phase of the project will extend the accessible state of matter a big step further. What’s more, the hydrodynamic behavior of the target under direct heating indicates that the beam parameter design for HEDP research should come to a compromise, which means, for example, with higher intensity or smaller focal spot, the beam pulse length must be compressed short enough to avoid the target dispersal before the end of the pulse.

We have measured the electron and X-ray emission of tungsten bombarded with proton in the energy range of 50–250 keV. It is found that the total electron yield mainly consists of kinetic electron emission, which results from the excited valence electrons, and presents a similar trend to the curve of stopping power. The ratio between electron yield and electronic energy loss is not constant, but decreases with increasing incident energy. The behavior is interpreted by an expected competitive mechanism of ionization between different shell electrons of target atom. The explanation is verified by the experimental increase of M-shell X-ray emission yield, and the measured and calculated ionization cross section of core and valence electrons.

β-SiAlON/h-BN composites with improved machinability and thermal shock resistance were fabricated via a reaction bonding procedure using raw materials of Si, Al 2 O 3 , AlN and h-BN. Effects of h-BN on properties of the composites, including density, strength, hardness, fracture toughness, machinability and thermal shock resistance, were investigated. XRD analysis was performed to analyze the phase composition of the composites, and SEM was employed to analyze their microstructure. The results showed that the density of the composites went through a maximum value with h-BN content increased from 0 to 50 wt%. Vickers hardness of the composites with less h-BN addition was decreased without obvious strength loss. Fracture toughness of the composites was decreased with h-BN content increased from 0 to 50 wt%. Drilling hole and thread tapping test showed that the machinability of the composites with h-BN addition was commendable. Thermal shock resistance of the composites with h-BN content higher than 20 wt% was excellent, and the retained strength of the composites was decreased slightly with the temperature difference and thermal shock times increased.

Doping and varying pump laser parameters are the widely applied technological processes for tuning spectra to yield desirable luminescence properties and functions. For micro/nanocrystalline materials, doping is of fundamental importance in modifying electronic properties, modulating magnetism, as well as tuning the red-to-green luminescence ratio. Here we describe a tunable upconversion (UC) emission process in single NaYF4:Yb/Er microtubes excitated with a focused laser. We show that the emission colours from single NaYF4:Yb/Er microtubes can be rationally tuned in the red-to-green luminescence ratio and dynamics process by elevating Yb3+ ion concentration or pump power density. The underlying mechanism of spectral tuning is explored by using the power dependent UC luminescence, downconversion spectra and the temporal evolutions of UC emission from a series of single NaYF4:Yb/Er microtubes. A mechanism of the red luminescence enhancement based on mediating electronic energy transfer channels by inducing three-photon processes is proposed for single microtubes. The natural decays of the luminescence levels are modified in the UC process relative to downconversion, which could be interpreted by using rate equations. Here, an insight into UC processes by use of unconventional focused experimental and theoretical techniques indicates the bidirectional feature of the electron transition of the interexcited-state by linear decays and UC processes via controlling external experimental parameters.

Over the past several years, a heterogeneous computing (HC) system has become more competitive as a commercial computing platform than a homogeneous system. With the growing scale of HC systems, network failures become inevitable. To achieve high performance, communication reliability should be considered while designing reliability-aware task scheduling algorithms. In this paper, we propose a new algorithm called RMSR (Replication-based scheduling for Maximizing System Reliability), which incorporates task communication into system reliability. To maximize communication reliability, an improved algorithm which searches all optimal reliability communication paths for current tasks is proposed. During the task replication phase, the task reliability threshold is determined by users and each task has dynamic replicas. Our comparative studies for both randomly generated graphs and application graphs of real-world problems show that our RMSR algorithm outperforms existing scheduling algorithms in terms of system reliability. For randomly generated graphs, several factors affecting the performance are analyzed in the paper. For an application graph of a real-world problem with a fixed DAG, the system reliability of the RMSR algorithm is at most influenced by one factor.

Nowadays, there are more and more criminal behaviors experiencing around the world, and crime spiking has become one of the most critical security and social issues in almost every country. It is critical to seek effective ways to discover these criminal behaviors and patterns and to carry out the prevention for the target place. In this paper, we formulate the problem of criminal behaviors and propose a Criminal Activity Clustering (CAC) algorithm. We introduce the fuzzy clustering method to detect potential criminal patterns in large-scale spatiotemporal datasets. In addition, for the improvement of the the proposed CAC algorithm performance, we implement a parallel solution for the algorithm in the Apache Spark cloud computing platform. The results of the experiment show that the proposed CAC algorithm can effectively detect accurate criminal patterns from large-scale spatiotemporal data.

Sparse matrix-vector multiplication (SpMV) is one of the important subroutines in numerical linear algebra widely used in plenty of large-scale applications. This paper focuses on scaling and optimizing SpMV for large-scale applications based on the memory structure and computing architecture of SW26010 CPU of the Sunway TaihuLight supercomputer. We propose the large-scale SpMV on the Sunway TaihuLight that includes two parts, i.e., the parallel partial (Compressed Sparse Row) CSR-based SpMV part and the parallel accumulation part. We respectively propose the adaptive partitioning methods and parallelization designs for the two parts of the large-scale SpMV based on the SW26010 architecture. The experimental results prove that the large-scale SpMV achieves high efficiency and good scalability on the Sunway TaihuLight.

In order to clarify the mechanism and the influence of the initial charge state and target atomic parameters for the formation of L-shell multiple ionization state of Arq+ ions produced by the collisions near the Bohr velocity, the k-shell x-ray emission of Ar is measured for 1.2 MeV Arq+(q=4, 6, 8, 9, 11, 12) ions impacting on V target and 3 MeV Ar11+ ions interacting with selected targets (Z2 = 23, 26, 27, 28, 29, 30). It is found that the measured Ar Kα and Kβ x-ray energies shift to the high energy side, and the relative intensity ratios of Kβ/Kα are enlarged than the atomic data, owing to the presence of out-shell multiple vacancies. The multiple ionization is almost independence of the projectile charge state, but is diminished with increasing target atomic number.

Water-purification membranes with high water flux, excellent recycling ability, good anti-fouling property, wide range for different oil/water emulsions separation, and strong water-soluble dyes removal ability are highly desirable for water purification but still a challenge to be realized. In this work, we show a simple method to address this challenge, in which halloysite nanotubes (HNTs) have been decorated on the poly (vinylidene fluoride) (PVDF) membrane surface through one-pot method via the aid of KH550 and dopamine. The HNTs@PVDF composite membrane exhibits superhydrophilic and under-water superoleophobic performance. In addition, our membrane can separate wide oil/water emulsions (including surfactant-stabilized and surfactant-free emulsions) from wastewater with high efficiency (>99.65%), outstanding recycle ability with good flux recovery rate (FRR > 95%) and good anti-fouling performance (the underwater oil contact angle (OCA) is 155.8 ± 1.8° with low oil adhesion) and high water flux (7994 ± 150 L m−2 h-1). Interestingly, our membrane also removes different water-soluble dyes (e.g., Congo red, methylene blue, and rhodamine B) from waste water by simply filtering. Those outstanding properties make our membrane hold great potential applications in real-world water purification and environmental protection.

Firstly, polyaniline (PANI) was used to improve dispersibility of graphene (Gr) in water through π-π interactions. Then, the obtained Gr/PANI products was further decorated with the epoxy based polyhedral oligomeric silsesquioxane (EPOSS) to enhance the hydrophobic properties of hybrid materials and compatibility with epoxy resins, thus leading to the increase of corrosion protection properties. From the wettability test results, the contact angle of the cross section of the composite coating reached up to 112.7 ° after grafting EPOSS, indicating that the hydrophobicity of the coating was improved significantly. Besides, the tensile strength of Gr/PANI@EPOSS/epoxy (0.7%) increased to 25.6 MPa, which proves the increase of interface force due to the introduction of epoxy group. The results of electrochemistry test illustrated that the impedance of Gr/PANI@EPOSS/epoxy (0.7%) is still as high as 2.79×107 Ω cm2 after 60 days of immersion, which is much higher than that of other samples.

Graphene oxide based nanofiltration membranes (GONMs) have attracted tremendous attention for water purification applications given their excellent mechanical properties and tunable inter-layer distance spacing (D-spacing). However, the desalination performance is significantly degraded in the pressure-driven filtration. In this work, we find that the pressure-driven water desalination properties are nanochannel spacing and length dependent, in which the cation-π interaction possibly plays a critical factor in the desalination procedure. Through the demonstration of surface weak-reduction and membrane thickness tuning, the D-spacing and molecule transport route length of GONMs are identified to affect the quality and quantity of cation-π interaction, respectively, which are innovatively regulated by the intercalation of nano-sized lattices into large GO sheets. As a result, the regulated membrane improves the rejection rates of MgCl2, NaCl, MgSO4 and Na2SO4 up to 41.10%, 64.14%, 84.62% and 93.19%, respectively, compared to unregulated counterparts of 13.72%, 15.93%, 34.58% and 40.99%, respectively. In addition, the regulated membrane also exhibits excellent removal efficiency of >93% against tested dyes with different molecular weight and surface charge properties. We consider that our approach could lead to the development of a powerful GONMs based platform for future water treatment.

As the best-known biosurfactant, rhamnolipid attracts increasing attention due to its manifold benefits, but the high production costs limit its large-scale application. To relieve the foam inhibition and reduce the cost of subsequent separation, foam separation was coupled with continuous fermentation to separate and concentrate biosurfactant in situ. A total rhamnolipid production of 3.574 g/L was obtained in continuous fermentation, which was nearly twice of that in batch fermentation. An average enrichment ratio of 9.397 and overall recovery rate of 56.113 % were obtained for foam separation. Furthermore, the continuous fermentation coupled with foam separation for rhamnolipid production was studied using a UV mutated strain, achieving improvements both in cell concentration and rhamnolipid concentration. Especially, the cumulative rhamnolipid concentration of 4.744 g/L was obtained, and an overall recovery rate as high as 72.892 % was achieved for foam separation. Results showed the integrated continuous fermentation with in situ foam separation was innovative and promising for biosurfactant production.

The poor water dispersion and oxidation resistance of carbon has restricted the widely industrial application of carbon containing castables. High aspect ratio network-like carbon nanotubes containing calcium aluminate cement composite powders were synthesized by carbon-bed sintering method using calcium acrylate and activated alumina as raw materials, and nickel nitrate as catalyst. Meanwhile the effects of catalyst content on the structure and morphology of carbon nanotubes were also studied. The synthesized products were characterized by X-ray diffraction, field-emission scanning electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy. The results indicated that the phase compositions of composite powders were similar to that of commercial Secar71. The length of carbon nanotubes was ca. 25 μm, and the diameter of carbon nanotubes was 55 nm. The aspect ratio of carbon nanotubes is ca. 450. The formation process and mechanism of carbon nanotubes was studied by thermogravimetric analysis coupled with Fourier transform infrared spectroscopy. The growth temperature of carbon nanotubes was 700 °C , and the growth of carbon nanotubes agrees with vapour–solid (V–S) model. In addition, the thickness of floating layer, floating ratio and oxidation ratios of the synthesized product were lower than those of the same carbon containing Secar71 cement (S71CB) composite powders, implying that the water dispersion and oxidation resistance of carbon nanotubes were improved because the high aspect ratio network-like carbon nanotubes were not easily separated from calcium aluminate cement and the carbon nanotubes were encased in calcium aluminate cement.

The corrosion failure cause analysis of Ma Huining × 52 oil pipeline has been investigated in the present study. The morphology and composition of the corrosion products are characterized by scanning electron microscopy, energy-dispersive spectroscopy and water quality analysis. The static and dynamic weight loss experiment is conducted to estimate corrosion rate of × 52 pipeline steel with different inhibitors. With the addition of electrochemical impedance test and polarization curve method, the inhibitors aimed at corrosion of Ma Huining oil pipeline have been evaluated. Results show that corrosion of × 52 pipeline steel is mainly induced by oxygen corrosion and SRB. Non-metallic inclusions are MnS and Al 2 O 3 . The inhibitor made up of oleic acid imidazoline amide and sodium sulfite at 80 ppm was optimal for corrosion of Ma Huining oil pipeline.

With the development of the economy, products are significantly enriched, and uncertainty has been their inherent quality. The probabilistic dynamic skyline (PDS) query is a powerful tool for customers to use in selecting products according to their preferences. However, this query suffers several limitations: it requires the specification of a probabilistic threshold, which reports undesirable results and disregards important results; it only focuses on the objects that have large dynamic skyline probabilities; and, additionally, the results are not stable. To address this concern, in this paper, we formulate an uncertain dynamic skyline (UDS) query over a probabilistic product set. Furthermore, we propose effective pruning strategies for the UDS query, and integrate them into effective algorithms. In addition, a novel query type, namely the top $k$ favorite probabilistic products (TFPP) query, is presented. The TFPP query is utilized to select $k$ products which can meet the needs of a customer set at the maximum level. To tackle the TFPP query, we propose a TFPP algorithm and its efficient parallelization. Extensive experiments with a variety of experimental settings illustrate the efficiency and effectiveness of our proposed algorithms.

β-SiAlON materials with different Z values (Z=0.5–3) were fabricated by a reaction bonding combining post-sintering route using raw materials of Si, Al2O3, AlN, etc. The reaction bonded β-SiAlON (RB-β-SiAlON) were post-sintered at 1,750 °C for 6 h. Apparent porosity, bulk density, bending strength and Vicker’s hardness of the samples before and after post-sintering were tested. XRD results showed that the phase composition of both RB-β-SiAlON and post-sintered RB-β-SiAlON (PSRB-β-SiAlON) were β-SiAlON. For RB-β-SiAlON, the apparent porosity was decreased with the increase of Z values, while the strength and hardness was increased accordingly. After the post-sintering procedure, nearly full densified PSRB-β-SiAlON was obtained and the mechanical properties were significantly improved. The bending strength and Vicker’s hardness of the PSRB-β-SiAlON (Z=0.5) achieved 510 MPa and 16.5 GPa, respectively, which were as 2.7 and 6.7 times high as those of the corresponding RB-β-SiAlON. However, the strength and hardness of PSRB-β-SiAlON decreased with the increase of Z value due to the grain growth.