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The staining procedure is critical for investigating intra- and extra-cellular ultrastructure of microorganisms by transmission electron microscopy (TEM). Here, we propose a new ultra-low lead staining (ULLS) technique for preparing the ultrathin sections for TEM analysis. Sections of Enterobacter sp. (bacteria), Aspergillus niger (filamentous fungi), Rhodotorula mucilaginosa (fungi), and Chlamydomonas reinhardtii (microalgae) were tested. Compared with the sections prepared by the typical double-staining technique, ULLS-based sections showed evident advantages: (i) the staining process only required the addition of Pb(NO3)2; (ii) the Pb level during incubation was set as low as 1 mg/L, which had negligible toxicity to most microbial cells; (iii) the Pb cations were added during microbial culture, which avoided complicated sample preparation as in typical double staining. Taking C. reinhardtii as an example, the ULLS technique allowed fine investigation of microbial ultrastructure, e.g., starch granule, mitochondrion, Golgi apparatus, vacuole, and vesicle. Meanwhile, the physiological processes of the cells such as cell lysis and exocytosis were successfully captured, with relatively high contrast. This study hence shows a bright future on preparation of the high-quality ultrathin sections of microbial cells by the ULLS technique.

Phenylethynyl-terminated polyimide resin/carbon fiber composites become ideal structure materials for aerospace vehicle because of excellent mechanical properties and high-temperature thermal stabi...

Polyoxymethylene dimethyl ether 3 has been regarded as a promising additive for reducing soot emissions in diesel engines. To better reflect the physical and chemical properties and combustion, emi...

It still remains challenging to simultaneously achieve high stability, selectivity, and activity in CO2 reduction. Herein, a dual chainmail-bearing nickel-based catalyst (Ni@NC@NCNT) was fabricated via a solvothermal-evaporation-calcination approach. In situ encapsulated N-doped carbon layers (NCs) and nanotubes (NCNTs) gave a dual protection to the metallic core. The confined space well maintained the local alkaline pH value and suppressed hydrogen evolution. Large surface area and abundant pyridinic N and Niδ+ sites ensured high CO2 adsorption capacity and strength. Benefitting from these, it delivered a CO faradaic efficiency of 94.1 % and current density of 48.0 mA cm-2 at -0.75 and -1.10 V, respectively. Moreover, the performance remained unchanged after continuous electrolysis for 43 h, far exceeding Ni@NC with single chainmail, Ni@NC/NCNT with Ni@NC sitting on the walls of NCNT, bare NCNT and most state-of-the-art catalysts, demonstrating structural superiority of Ni@NC@NCNT. This work sheds light on designing unique architectures to improve electrochemical performances.

Selective phenol hydrogenation is a green approach to produce cyclohexanone. It still remains a big challenge to prepare efficient supports of the catalysts for the phenol hydrogenation via a simple and cost-effective approach. Herein, a facile approach was developed, i.e., direct calcination of activated carbon (AC) under argon at high temperature, to improve its structure and surface properties. The modified AC materials were supported with Pd nanoparticles (NPs) to fabricate the Pd/C catalysts. The as-prepared Pd/C600 catalyst exhibits superior catalytic performance in the phenol hydrogenation, and its turnover frequency (TOF) value is 199.2 h−1, 1.31 times to that of Pd/C-raw. The Pd/C600 catalyst presents both better hydrophobicity and more structural defects, contributing to the improved dispersibility in the reaction solution (phenol-cyclohexane), the better Pd dispersion and the smaller Pd size, which result in the enhancement of the catalytic performance. Furthermore, the as-prepared Pd/C600 catalyst shows a good recyclability.

Preeclampsia has impacted 3-5% pregnancies among the world and its complications lead to both maternal and fetal morbidity and mortality. However, management of preeclampsia is limited. Nanoparticles targeting chondroitin sulfate A (CSA) can deliver drugs to placenta. Inactivation of soluble fms-like tyrosine kinase (sFlt-1) and nuclear factor-erythroid 2-like 2 (Nrf2) has been proved to alleviate preeclampsia and improve maternal and fetal outcomes. Carboxyl-polyethylene glycol-poly (d,l-lactide) (COOH-PEG5K-PLA8K), cationic lipid DOTAP, and siNrf2 and sisFlt-1 were used to construct the nanoparticles and conjugating peptides targeting CSA was fabricated to it. The expression levels of proteins and RNAs were estimated by qRT-PCR and Western blot assays. ELISA assays were performed to evaluate levels of circulating sFlt-1. The nanoparticles containing siNrf2 and sisFlt-1 are targeted to the placenta trophoblasts and downregulated the expression levels of Nrf2 and sFlt-1 as well as their downstream genes in the placental cells of model mice. Treatment of nanoparticles induced the expression of angiogenic factors in placenta. Knocking down Nrf2 and sFlt-1 synchronously alleviated the preeclampsia and increased the maternal and fetal outcomes in preeclampsia model mice. Nanoparticle-mediated simultaneous downregulation of placental Nrf2 and sFlt1 improved maternal and fetal outcomes in a preeclampsia mouse model.

A novel methanol-to-olefins (MTO) reactor in which two parallel reaction zones were created by introducing a draft tube to a column bed was numerically investigated using a combination of multi-fluid model and two types of EMMS drags, in order to explore the favorable hydrodynamics. The further numerical comparison of the novel reactor and a conventional reactor found that the introduction of a draft tube helps increase the gas velocity substantially, building an approximate plug flow in the center and concurrent downward flow in the annulus. The gas-solid contact time and solids backmixing in the draft tube were thus greatly reduced, being favorable to MTO reactions, while the gas and solids backmixing in the annulus was enhanced. Besides, severe gas bypassing from the annulus to the draft tube was detected. A gas tracer method was then adopted to quantify the gas bypassing and internal gas circulation for further optimization.

Isopropanol-butanol-ethanol (IBE) can be utilized as a clean transportation fuel to avoid the production cost of bio-butanol as well as the plastic-degradation issues of acetone-butanol-ethanol (AB...

In this study, various wavelet analysis methods are used to investigate possible influences of large-scale climate patterns, such as El Nino-Southern Oscillation (ENSO), North Atlantic Oscillation (NAO), Pacific Decadal Oscillation (PDO), and Indian Ocean Dipole (IOD), on precipitation extremes over Beijing-Tianjin-Hebei region in China at different time scales. Firstly, the temporal patterns of precipitation extremes are detected by wavelet transform. Significant annual or inter-annual oscillations for the precipitation extremes during 1958–2017, with periodicities of around 0.5–1 year, 1–2 years, and 2–5 years were being found for monthly, seasonal, and annual time series, respectively. Subsequently, wavelet coherence method is used to identify the dominant driving factors of precipitation extremes, with ENSO, IOD, and NAO showing stronger correlations with monthly, seasonal, and annual precipitation extremes, respectively. Meanwhile, partial wavelet coherence analyses indicate that the standalone influences of climate factors may be weak, and the influences seem to be stronger because of their interdependences on other climate indices. Finally, multiple wavelet coherences reveal that variations of precipitation extremes could be better explained by combinations of two or more factors, although the additional explanatory variable may have not a significant increase in percent number of significant coherence.

Selective hydrogenation of phenol is a green strategy to produce cyclohexanone. Achieving high phenol conversion and cyclohexanone selectivity under mild conditions is a significant challenge in th...

Two typical coatings (nickel-based and iron-based) were successfully fabricated on AISI 304 stainless steel via cold metal transfer process as alternative materials with superior wear and cavitation erosion resistance, respectively. Scanning electron microscopy, X-ray diffraction and electron backscattering diffraction were performed to characterize the morphologies, phase composition and crystallographic textures. Subsequently, tribology, cavitation erosion as well as corrosion tests were carried out to analyze the applicability of the coatings in various environments. Experimental results showed that the coatings exhibited few defects and an excellent metallurgical bonding with the substrate, and possessed the strong textural features. The microhardness of the coatings was ∼ 3 times higher than that of the substrate, and the microhardness of nickel-based coating was more stable than that of the iron-based one. Combining with the cumulative volume/weight loss and morphologies, the wear and cavitation erosion resistance of the coatings and substrate were compared, and failure mechanisms were proposed. It was found that the cumulative volume/weight loss of the coatings are one order of magnitude lower than that of the substrate. The combination of toughness and fine dispersed carbides had guaranteed the higher wear resistance of iron-based coating, while the formed massive phases of nickel-based coating played a significant role in the cavitation erosion and corrosion resistance.

The study investigated novel wear and corrosion resistance of stainless steel and 316 stainless steel samples which were successfully prepared by laser melting deposition. Phase composition, microstructure, microhardness, wear resistance, and electrochemical corrosion resistance were studied. The experimental results showed that novel stainless steel was mainly composed of a-Fe and a few carbide phase (Cr, Fe)7C3. The microhardness of novel stainless steel was about 2.7 times greater than 316 stainless steel. Meanwhile, the specific wear rate of novel stainless steel and 316 stainless steel was 2.63 × 10-5 mm3/N m and 1.63 × 10-4 mm3/N m, respectively. The wear volume of 316 stainless steel was 6.19 times greater than novel stainless steel. The corrosion current and the corrosion potential of novel stainless steel and 316 stainless steel were 1.02 × 10-7 A/cm2 and 1.5 × 10-7 A/cm2, and -138.8 mV, -135.9 mV, respectively, in 3.5 wt% NaCl solution. Therefore, both microhardness and wear resistance of novel stainless steel were greatly improved, with high corrosion resistance.

Silk fibers were produced by feeding Bombyx mori silkworm larvae with a modified feed of mulberry leaves containing nano Fe3O4 particles. The silkworms were weighed to determine the effect of nano ...

Conventional cellulose diacetate filter tips of cigarette (CDFTC) are poor filtration performance of toxic compounds. However, environmentally benign filter tips can be made by replacing cellulose ...

With the deep integration of cyber physical production systems in the era of Industry 4.0, smart workshop dramatically increases the amount of data collected by smart device. A key factor in achieving smart manufacturing is to use data analysis methods for evaluating the equipment reliability and for supporting the predictive maintenance of equipment. Based on these insights, this paper proposes a deep learning-based approach that uses time series data for equipment reliability analysis. First, a framework of the TensorFlow-enabled deep neural networks (DNN) model for equipment reliability analysis is presented. Secondly, using time series equipment data, an evaluation strategy of equipment reliability based on deep learning is proposed. Finally, the reliability of a cylinder, an important part of the small trolley in automobile assembly line, is evaluated in a case study. Compared with the traditional reliability analysis method such as PCA and HMM, the prediction results show a significant improvement in prediction accuracy. This work contributes to promoting artificial intelligence algorithms for realizing highly efficient manufacturing.

Juncus effusus (JE) is a natural cellulose fiber with unique three-dimensional network structure and interconnected channels. However, to the best of knowledge, no efforts have been dedicated to the influence of alkali treatment on the morphologies and properties of the JE fibers, which can contribute to the removal of dyes from wastewater. Herein, the natural cellulose JE fibers were subjected to alkali treatment various concentrations of NaOH. The mechanical, chemical, thermal, wetting, and surface morphological properties of alkali-treated JE fibers were examined using a variety of experimental techniques, confirming that the chemical and mechanical properties of the JE fibers were enhanced after alkali treatment. Fibers treated with 4% w/v NaOH exhibited a maximum tensile strength of 200.63 ± 36.38 kPa and elongation at break of 12.10% ± 2.69%. During alkali treatment, amorphous material such as hemicellulose was partial removed and the crystallinity index of the alkali-treated JE fibers was enhanced. The treated fibers exhibited a rough morphology owing to the removal of hemicelluloses. Future studies will mainly focus on the applicability of alkali-treated JE fibers for the removal of dyes from wastewater.

Rugged karst terrain relief that creates shadows in satellite imagery, combined with high karst landscape heterogeneity stand in the way of fractional cover retrieval on karst rocky desertification (KRD) monitoring. In this study, we explored the feasibility of applying multispectral high spatial resolution Advanced Land Observing Satellite (ALOS) imagery for the fractional cover extraction of rocky outcrops. Dimidiate pixel model (DPM) and spectral mixture analysis (SMA) approaches (including simple endmember spectral mixture analysis and multiple endmember spectral mixture analysis) were selected to explore their feasibility for KRD monitoring through accuracy improvement for fraction estimation. Results showed fractional cover retrievals at the sub-pixel scale is essential in highly heterogeneous karst landscapes. Indeed, mixed pixels accounted for 93.7% of the study area in southwest China. Multiple endmember spectral mixture analysis achieved high overall accuracy (80.5%) in monitoring the percentage of rocky outcrop land cover. Furthermore, the predicted exposed bedrock coverage via spectral mixture analysis were similar in sunlit and shadow areas for the same surface types. This reflected that SMA methods could effectively reduce topographic effects of satellite imagery to improve the accuracy of fractional cover extraction at sub-pixel level in heterogeneous and rugged landscapes.

Improvement of anti-chlorine and anti-bacterial properties of membranes has been a major challenge in desalinating process. In this paper, zero-dimension cage-like structure polyhedral oligomeric silsesquioxane (POSS) was in situ armored on the surface of polyamide (PA) membrane and acted as ‘armors’ to prevent active chlorine corrosion and bacterial fouling. PA/POSS hybrid membranes could be easily achieved through a simple two-step interfacial polymerization. Anti-chlorine and anti-bacterial properties of PA/POSS hybrid membranes significantly improved during desalination by tuning the content of POSS ‘armors’. Salt rejection reached approximately 98% after immersing PA/POSS hybrid membranes in the active chlorine solution for 24 h, which showed excellent anti-chlorine property. In addition, the anti-bacterial property of PA reverse osmosis (RO) membranes extremely enhanced after armoring with POSS nanoparticles. This finding demonstrated that the structure and chemical inert nature of POSS enabled PA/POSS membranes to block active chlorine and bacteria. PA/POSS membranes provided a promising approach to improve membrane desalination.

In this paper, a fractional step lattice Boltzmann method is proposed to model two-phase flow with large density differences by solving a modified Cahn-Hilliard phase-field equation and the incompressible Navier-Stokes equations. In order to maintain the interface profile and conserve the volume, the normal flux in the original Cahn-Hilliard equation is removed and a profile-corrected term to enforce the interface to be a hyperbolic tangent profile is added. The modified Cahn-Hilliard equation is split to two sub-equations. One is the original CH equation and the other is the correction equation. Both the original CH and the hydrodynamic equations are solved by the lattice Boltzmann method. The correction equation is solved by the finite difference method. With the multi-relaxation-time collision model and a high-order compact selective filter operation employed in the lattice Boltzmann method, numerical stability is much improved. Compared with the previous lattice Boltzmann methods, the proposed method is able to maintain the order parameter within a physically meaningful range, which is capable of tracking the interface accurately. The proposed method can also simulate two-phase fluid flows with the density ratio up to 1000. Several benchmark problems, including single vortex deform of a circle, translation of a drop, stationary droplet, capillary wave and rising bubble with large density ratios, are presented to validate the accuracy and efficiency of the present method.

To study the contamination of heavy metals in the aquaculture area of Beibu Gulf, the concentrations of seven metals in seawater were investigated. The results showed that significant seasonal and ...

Metal matrix composites (MMCs) self-lubricating coatings were fabricated on 35CrMo steel by laser cladding using Co-based alloy and Ti3SiC2 mixture, aiming at improving the wear resistance of 35CrMo steel. Phase constituents, microstructure, microhardness and wear property of the MMCs coatings with different Ti3SiC2 content were investigated using XRD, SEM, microhardness tester, and friction-wear tester, respectively. Experimental results showed that with appropriate laser processing parameters, crack and porosity-free coatings with good metallurgical bonding to the substrate could be obtained. The coatings were mainly composed of γ-Co, Ti3SiC2, Cr7C3 and TiC. During the cladding process, Ti3SiC2 partially dissolved to form TiC. The microhardness of the coatings was significantly enhanced, which was at least 2.3 times that of substrate. The wear resistance of the coatings was 3.6–6.2 times that of substrate and the coating with 10 wt% Ti3SiC2 addition possessed the highest wear resistance.

Multi-color and white light luminescence materials based on supramolecular assemblies are attractive because of their potential applications in advanced light-emitting material. Herein, a cucurbit[8]uril-enhanced lanthanide luminescent supramolecular assembly was constructed in a facile but efficient way using terpyridine imidozalium cations, cucurbit[8]urils and rare earth ions such as Tb3+ and Eu3+. Significantly, the resultant fibrous supramolecular assembly, with an average width of 15 nm, could emit remarkable lanthanide luminescence, which was ten times higher than the corresponding terpyridine/Ln3+ without cucurbit[8]uril. And the solid state luminescence of supramolecular assembly could be smartly and easily turned among blue, green, red and white by adjusting the molar ratios between Tb3+ and Eu3+. The enhanced white-light emission by supramolecular strategy may provide a new approach for smart and tunable solid luminescent materials.

With the growing shortage of energy, wind power is receiving an increasing amount of attention worldwide as a clean source of renewable energy. One of the most important components of the wind turbine is the bird-wing-like blade under the working principle. Three kinds of bionic blades are designed by using bionic wing type and configuration based on the good aerodynamic performance of seagull wings, combined with the theory of wind turbine blade design-the blade element theory. Standard blade and aerodynamic performances of bionic blade are evaluated by means of numerical simulation. Under different wind speeds, the results show that the blade torque of the bionic blade of total improved airfoil increases by 10.2%, the bionic blade of partially improved airfoil increases by 14%, and the configuration improved blade increases by 7%. To verify the correctness of the numerical simulation results, we run the bionic blade and establish a corresponding experimental device in an actual experiment. The results of the experiment are consistent with the trend of the numerical simulation.

Direct laser metal deposition (DLMD) can produce near net shape parts by layer-by-layer deposition of metallic powders. In the present study, DLMD was used to fabricate a high strength low alloy (HSLA) steel. The characteristics of the microstructure and mechanical properties of the as-built HSLA were characterized using optical microscopy, electron back-scatter diffraction (EBSD), transmission electron microscopy, and tensile test machine respectively. It was found that the optimized parameters ensured a high quality of the built samples. The as-built HSLA steel was mainly composed of α-Fe (Ferrite) phase with a trace of C6Cr23 and Fe3C phases. TEM result proved the formation of martensite phase. Most grain boundaries misorientation angles were low-angle grain boundary which elevated the strengthening effect. Tensile strength, yield strength, and elongation of the as-deposited HSLA were comparable with other high-performance alloy steels. The present results show the potential of DLMD for the fabrication of a HSLA with excellent mechanical properties.

Extracellular polymeric substances (EPS) are biopolymers secreted by microorganisms such as bacteria, fungi, and algae that may play a significant role in the speciation, toxicity, and biog...

To study the adsorption characteristics of CO, CO2, N2, O2, and their binary-components in lignite coal, reveal the influence of CO2 or N2 injection and air leakage on the desorption of CO in goafs, a lignite model (C206H206N2O44) was established, and the supercell structure was optimized under temperatures of 288.15–318.15 K for molecular simulation. Based on molecular dynamics, the Grand Canonical Monte Carlo method was used to simulate the adsorption characteristics and the Langmuir equation was used to fit the adsorption isotherms of gases. The results show that for single-components, the order of adsorption capacity is CO2 > CO > O2 > N2. For binary-components, the competitive adsorption capacities of CO2 and CO are approximate. In the low-pressure zone, the competitive adsorption capacity of CO2 is stronger than that of CO, and the CO is stronger than N2 or O2. From the simulation, it can be seen that CO2, N2 or O2 will occupy adsorption sites, causing CO desorption. Therefore, to prevent the desorption of the original CO in the goaf, it is not suitable to use CO2 or N2 injection for fire prevention, and the air leakage at the working faces need to be controlled.

The experiments were conducted on a modified two-cylinder diesel engine to investigate the effects of excess-air coefficient (λ) and intake temperature (Tin) of different blending ratios (volume ratio of gasoline in the blends) on the combustion and emission characteristics of a Partially Premixed Compression Ignition (PPCI) engine. The results show that with the increase of gasoline blending ratio, the peak in-cylinder pressure (Pmax), the peak in-cylinder temperature (Tmax) and the peak heat release rate (HRRmax) of four test fuels all increase first and then decrease. When gasoline volume fraction is 10%, HC and CO emissions are the lowest. In addition, intake temperature (Tin) has a significant effect on the n-butanol/gasoline PPCI engine. With the increase of Tin, the in-cylinder Pmax and HRRmax of four test fuels gradually increase, the combustion phase advances and HC and CO emissions decrease, while NOx emissions increase slightly. Furthermore, as λ increases, the Pmax, Tmax and HRRmax of the four test fuels show monotonously reducing trend. At the same time, mixture concentration has basically no effect on start of combustion (CA10), the combustion duration (CD) gradually extends, and HC and CO emissions increase.

Eco-friendly ethanol (EtOH)-water (H2O) mixture has demonstrated huge potential in the textile industry. However, the uncontrolled discharge of dye-contaminated EtOH-H2O mixture to the ecosystem has numerous adverse effects. Herein, a sustainable approach utilizing the agricultural waste biomass-Juncus effusus (JE) to synthesize magnetic cellulose JE powders (M-JEPs) has been proposed for purification of dye-contaminated EtOH-H2O mixture. Batch experiments and physical-chemical analyses were performed to explore the adsorption performance and mechanism. The as-prepared cellulose M-JEPs exhibited ultrafast adsorption performance, which can reach the adsorption equilibrium within 10 min. The adsorption isotherms and kinetics demonstrated that the adsorption fitted well with the Langmuir isotherm and pseudo-second-order kinetic models, exhibiting the maximum adsorption capacity towards C.I. Reactive Red 195 and C.I. Reactive Blue 222 of 58.21 mg/g and 86.06 mg/g at the temperature of 303K. These findings indicate the feasibility of using cellulose M-JEPs for rapid purification of the dye-contaminated EtOH-H2O mixture.

The homogeneous charge compression ignition (HCCI) combustion was conducted on a modified engine to investigate the effect of hydrogen peroxide (H2O2) additive on the combustion and emission characteristics, such as the indicated thermal efficiency (ηi), the total hydrocarbon (THC), the carbon monoxide (CO) and the nitrogen oxides (NOx) emissions. A simulation using CHEMKIN software was also performed to analyze the experimental data. The results indicate that the addition of H2O2 facilitates the formation of hydroxyl (OH) radical and hydroperoxyl (HO2) radical in the cylinder under HCCI mode, which greatly affects the combustion and emission characteristics of the n-butanol HCCI engine. By adding H2O2, ηi increases, NOx emission remains at an ultra-low level, but THC and CO emissions reduce at almost all the test conditions. Especially at the low intake temperature (Tin) or low load condition, the improvements are very obvious, which suggests that addition of H2O2 may extend the low Tin and low load limits of HCCI engines.

Atmospheric particulate samples were collected during three typhoons in 2006 (Chanchu, Bilis, and Kaemi) from Dongshan and Pingtan Islands along the coastal areas of Fujian Province and were analyz...

This study is aimed to investigate the performance, combustion, and emissions of a common-rail diesel engine fueled with IBE and diesel blends. Two blends of IBE and diesel fuel, denoted as IBE15 (15% IBE and 85% diesel in volume) and IBE30 (30% IBE and 70% diesel in volume), were tested under different injection strategies. The experimental results show that compared with single injection, the in-cylinder pressure and heat release rate curves (HRR) for all the tested fuels under double injection cases are less severe. That is to say, a pilot injection can reduce knocking combustion and ringing intensity when blending a high ratio of IBE into diesel. Furthermore, double injection is helpful in improving both engine performance and economy for all the tested fuels, especially for IBE30. For almost all the tested conditions, both IBE15 and IBE30 present a potential to reduce soot emissions but increase NOx emissions. A pilot injection is favorable to reduce NOx emissions but causes the soot emissions to increase. Results also show that the flame lift-off length of IBE30 is much longer than that of pure diesel. This feature may result in better air-fuel mixing, which then contributes to reduce soot emissions.

Industry 4.0, which exploits cyber-physical systems and represents digital transformation of manufacturing, is deeply affecting healthcare as well as other traditional production sector. To accommodate the increasing demand of agility, flexibility, and low cost in healthcare sector, a data-driven reconfigurable production mode of Smart Factory for pharmaceutical manufacturing is proposed in this paper. The architecture of the Smart Factory is consisted of three primary layers, namely perception layer, deployment layer, and executing layer. A Manufacturing's Semantics Ontology based knowledgebase is introduced in the perception layer, which is responsible for plan scheduling of pharmaceutical production. The reconfigurable plans are generated from the production demand of drugs as well as the information statement of low-level machine resources. To further functionality reconfiguration and low-level controlling, the IEC 61499 standard is also introduced for functionality modeling and machine controlling. We verify the proposed method with an experiment of demand-based drug packing production, which reflects the feasibility and adequate flexibility of the proposed method.

A novel aromatic polyamide (PA) reverse osmosis membrane with nanoscale water channels and hydrophilic molecular skin surface, similar to those of biomimetic neural networks, was realized for textile wastewater treatment via the facile strategy of interfacial polymerization with the addition of free radicals. The free-radical polymerization of diallyl dimethyl ammonium chloride, dispersed inside and on the surface of the PA functional layer, was initiated by irradiation to form a polyimide-hydrophilic polyolefin interpenetrating network structure as the functional layer and a molecular brush as the hydrophilic surface layer. Compared with the thin film composite (TFC) membrane, the water contact angle of the modified membrane was reduced drastically from 58.23° to 19.95°, and surface roughness and negative charge also decreased. Moreover, the water flux and salt rejection performances of the modified membrane improved simultaneously. The hydrophilic polyolefin network exhibited the same structure and function as those of neural networks, through which water molecules, but not salts, could pass through nanoscale water channels formed by polymerization. Then, contaminant rejection rates using TFC or modified membranes for textile wastewater treatment were investigated. The modified membrane yielded high rejection (>99%) of ion salts and high chemical oxygen demand removal (>99.3%) of organics with low molecular weights. Apart from its excellent anti-fouling property, the modified membrane was also satisfactorily stable for long-term separation. The integration of low-cost, high-performance, and facile strategy indicates the potential application of the proposed membrane for textile wastewater treatment.

Anonymous authentication has significant contribution to privacy protection in safety message dissemination for Vehicular Ad Hoc Networks (VANETs); however, it suffers from heavy workload of vehicle revocation check and message signature verification, which leads to unsatisfactory timeliness and high message loss rate in heavy traffic situations. To manage these challenging problems, this paper proposes an efficient safety message authentication protocol for VANETs by combining batch group signature verification and our proposed Group Session Key (GSK). Specifically, our signature verification method for safety message can both achieve computation efficiency by reducing the number of computation operations of bilinear pairing and resist impersonation attack by using tracking key implement. GSK is associated with the forward and backward keys and is only shared among unrevoked vehicle within a group. Performance analysis and simulations demonstrate that our protocol can provide promising security against various common types of attackers and is more efficient than traditional group-signature-based authentication protocols, in terms of computation time cost, authentication delay and message loss rate.

Low pressure premixed laminar dimethyl ether/oxygen/argon flames with different equivalence ratios (0.8, 1.0, and 1.5) were investigated experimentally and numerically. The major intermediates were identified, and their mole fractions were measured using molecular-beam mass spectrometry combined with synchrotron radiation photoionization. Simulations were performed using PREMIX CODE and a representative chemical reaction model for dimethyl ether. The influence of the equivalence ratio on the flame structure and reaction path of dimethyl ether was analysed. The results show that formaldehyde and methyl are the main C1 intermediates in dimethyl ether flames. Dimethyl ether is mainly consumed through H-abstraction reactions by H, OH, CH3, and O. The effect of these radicals on the H-abstraction reactions varies at different equivalence ratios. Most of the methoxy-methyl radicals formed by the H-abstraction reactions promptly undergo β-scission into methyl and formaldehyde, with only a small amount reacting with oxygen under extremely lean conditions.

Acetone–Butanol–Ethanol (ABE), as an alternative for butanol, can be used either in neat form or in blends with fossil fuels. Yet the flame characteristics of ABE blending gasolines have not been reported to date. To explore the effects of ABE addition on the laminar flame speed of gasoline, the spherical propagating flames of ABE, gasoline (represented by toluene reference fuel, TRF), as well as ABE-TRF mixture were measured at an initial condition of 1 bar, 400 K, and an equivalence ranging from 0.8 to 1.6. The results indicated that with an addition of 20% ABE fuel, the laminar flame speeds of ABE-TRF flame showed apparent increments at stoichiometric and ϕ = 1.2 flames. The normalized increment of laminar burning velocity I v raised monotonically with the increase of equivalence ratio. The three ABE-TRF mixtures showed small increment of laminar burning velocity than TRF flame in the order of u n . ABE 20631 u n . ABE 20361 u n . ABE 20163 , suggesting a suppressing effect of acetone addition on the mixture burning velocity of ABE-TRF mixtures. ABE fuel with more alcohol contents extended the range of stable flame while acetone addition diminished the flame diffusional thermal stability. The kinetic analysis showed that the rate-limiting reactions shifted from heavier molecular reactions to lighter ones by blending the ABE fuel into TRF, as well as the rate of production (ROP) of OH radical increased by 5.5%. The sensitivity reactions for rich ABE-TRF flames are also more dependent on light fractions compared to lean flames.

This study investigates the use of water for extracting shale gas in the Sichuan Basin of China. Both net water use and water intensity (i.e., water use per unit of gas produced) of shale wells are estimated by applying a process-based life cycle inventory (LCI) model. The results show that the net water use and water intensity are around 24500 m3/well and 1.9 m3 water/104 m3 gas respectively, and that the fracturing and completion stage of shale gas extraction accounts for the largest share in net water use. A comparison shows that China's water use for shale gas extraction is generally higher than that of other countries. By considering the predicted annual drilling activities in the Sichuan Basin, we find that the annual water demand for shale gas development is likely to be negligible compared to total regional water supply. However, considering the water demand for shale gas extraction and the water demand from other sectors may make water availability a significant concern for China's shale gas development in the future.

In order to reduce the fuel consumption and hydrocarbon and CO emissions of liquefied natural gas-diesel dual-fuel engines under light loads, an optimization control scheme, in which the dual-fuel engine runs in original diesel mode under light loads, is used in this paper. The performance and exhaust emissions of the dual-fuel engine and the original diesel engine are compared and analyzed by bench tests of an electronic control common-rail diesel engine. Experimental results show that the brake-specific fuel consumption and hydrocarbon and CO emissions of the liquefied natural gas-diesel dual-fuel engine are not deteriorated under light loads. Compared with diesel, the brake power and torque of dual-fuel remain unchanged, the brake-specific fuel consumption decreases, and the smoke density and CO2 emissions of dual-fuel decrease, while the hydrocarbon and CO emissions increase, and there is no significant difference in NOx emissions.

Graphene oxide nanoribbons (GONRs), as a new member of carbon family, attracted extensive attention in industry and science field. It has considered to be as a promising nanomaterial for applications in the field of materials science, energy storage and optics science due to its extraordinary mechanical, electrical and thermal properties. Hence, in this study, we carried out a facile and efficient strategy for preparing poly (phenylene benzobisoxazole) (PBO)/GONRs(PGR) composite fibers via one-pot in situ polycondensation method for enhancement in mechanical and thermal properties. The GONRs sheets in this work were obtained by unwrapping multi-walled carbon nanotubes (MWCNTs) side walls, and then directly reacted with PBO monomer 4,6-diaminoresorcinol(DAR) and covalently grafted on PBO molecular chains. The structure and morphology of GONRs and modified GONRs were well demonstrated by the FT-IR, XPS and TEM analysis for confirming the formation of chemical bond between GONRs and PBO molecular chains. The mechanical and thermal properties of PGR composite fibers were also investigated. It was found that the performance of composite fibers about 32.1% improvement in tensile modulus, 24.2% in tensile strength and 10.5% thermal stability, respectively.

In situ synthesized V8C7 reinforced Fe-based composite coating was successfully prepared on 35CrMo steel by laser cladding, aiming at improving the wear resistance. Constituent phases, microstructure, microhardness and wear resistance of the coating were investigated using XRD, SEM, microhardness tester and friction-wear tester. The results showed that the obtained coating was uniform and dense with no pores or cracks appearing, in addition to satisfied metallurgical bonding to the substrate. The coating was mainly composed of α-Fe, V8C7, Cr7C3, Fe3C and Mo2C phase. Fine V8C7 reinforced particles were in situ synthesized during the melting process. The shape of V8C7 particles changed from sphere to irregular blocks as a distance from the interface, which was due to the crash and binding of V8C7 particles with each other. The microhardness of coating was 775 HV0.3, which was about 4 times greater than the substrate. The wear resistance of the coating was significantly improved as indicated by the higher relative wear resistance.

The concentration of tetrahydrofuran (THF) was used to regulate the pore morphologies of PU films using a THF/N,N-dimethylformamide (DMF) binary solvent. Macro-void, micro-pore, and potential inter-connected pores are classified according to the cross-sectional FESEM images. Corresponding pore forming mechanisms are proposed. The water vapor permeability (WVP) was linked with total pore areas of different kinds of pores. Mechanical properties as a function of THF concentration was also investigated. Optimized PU coating could be achieved at a 40 wt% THF bearing the tensile stress, strain, toughness, and WVP of 9.2 ± 0.6 MPa, 1063.7 ± 57.1%, 43.6 ± 3.8 MJ m−3, and 1894.3 ± 41.3 g m−2·day−1, respectively. This provides an alternative avenue for the production of PU coating with balanced mechanical property and WVP.

International audience; Recently, severe droughts that occurred in North America are likely to have impacted its terrestrial carbon sink. However, process-based understanding of how meteorological conditions prior to the onset of drought, for instance warm or cold springs, affect drought-induced carbon cycle effects remains scarce. Here we assess and compare the response of terrestrial carbon fluxes to summer droughts in 2011 and 2012 characterized by contrasting spring conditions. The analysis is based on a comprehensive ensemble of carbon cycle models, including FLUXCOM, TRENDY v5, SiBCASA, CarbonTracker Europe, and CarbonTracker, and emerging Earth observations. In 2011, large reductions of net ecosystem production (NEP; À0.24 ± 0.17 Pg C/year) are due to decreased gross primary production (À0.17 ± 0.18 Pg C/year) and slightly increased ecosystem respiration (+0.07 ± 0.17 Pg C/year). Conversely, in 2012, NEP reductions (À0.17 ± 0.25 Pg C/year) are attributed to a larger increase of ecosystem respiration (+0.48 ± 0.27 Pg C/year) than gross primary production (+0.31 ± 0.29 Pg C/year), induced predominantly by an extra warmer spring prior to summer drought. Two temperate ecoregions crops/agriculture and the grass/shrubs contribute largest to these reductions and also dominate the interannual variations of NEP during 2007-2014. Moreover, the warming spring compensated largely the negative carbon anomaly due to summer drought, consistent with earlier studies; however, the compensation occurred only in some specific ecoregions. Overall, our analysis offers a refined view on recent carbon cycle variability and extremes in North America. It corroborates earlier results but also highlights differences with respect to ecoregion-specific carbon cycle responses to drought and heat.

Isopropanol-butanol-ethanol (IBE) can be used in engines as an alternative fuel to eliminate the high recovery and separation costs in the production of butanol and also to avoid the corrosivity and low flash point of acetone in acetone-butanol-ethanol (ABE). In this respect, this study is aimed to investigate the performance, combustion and emissions of a single-cylinder, common-rail diesel engine fueled with IBE and diesel blends. Two blends of butanol and diesel fuel, denoted as IBE15 (15% IBE and 85% diesel in volume) and IBE30 (30% IBE and 70% diesel in volume) were tested. Additionally, the experiments in this study were conducted at different diluted gas ratios to achieve low NOx emission. The experimental results show that when the intake charger is gradually diluted, the start of combustion and combustion center for all the tested fuels are remarkably delayed. Compared with pure diesel, the brake thermal efficiency (BTE) for IBE15 is always higher. Butt for IBE30, the BTE is lower than that of pure diesel when the flow rate of the dilute gas is less than 30 L/min. For all the tested fuels, NOx emission reduces while CO and HC emissions increase with the increase of dilute gas. Soot emission for pure diesel and IBE15 drastically increases as the dilute gas increases. However, the increase of dilute gas does not cause the soot emission of IBE30 to significant increase. That is to say, IBE30 coupled with a proper EGR ratio has the potential to reduce NOx and soot emissions simultaneously.

Multi-label learning is the problem where each instance is associated with multiple labels simultaneously. Binary Relevance (BR), which comes from the idea of one-vs-all for multi-class classification, is a representative algorithm for multi-label learning. It ignores label correlations and may suffer the class-imbalance problem. However, BR is mostly implemented by decomposing into many independent binary classifiers and learning each individually, making it difficult to extend. Moreover, when extending BR by learning together, the mostly used least squared loss function is more suitable for a regression task rather than a classification task. In this paper, we propose a unified framework implementing linear BR for multi-label learning, which is easy to extend and can also be applied in one-vs-all for multi-class classification. We mainly focus on five popular convex loss functions. Experimental results show that the unified framework achieves competitive performances than traditional implementations and some other well-established algorithms for both multi-label learning and multi-class classification. Furthermore, logistic, exponential and least squared hinge loss functions are more suitable for multi-label learning, while logistic and least squared hinge loss functions are more suitable for multi-class classification.

Unmodified ZrO2 nanoparticles (ZDNPs) are used for the enhancement of polyurethane (PU) films. Optimized strain and toughness of PU/ZDNP nanocomposite at 9.09 wt % ZDNPs are up to 2714.6%, and 280.8 MJ m–3, respectively. The unique bimodal ZDNP aggregate size distribution which exploits both interfacial positively and negatively toughening mechanisms accounts mainly for the excellent mechanical property of PU/ZDNP nanocomposite. The dependence of different toughening mechanisms on three sizes of ZDNP aggregates is summarized. These findings provide a new avenue for the industrial production of nanocomposites at low cost without surface modification of inorganic nanoparticles.

High-strength raw silk fibers were obtained by feeding the silkworm larvae with a modified feed containing down-powder. The relationship between different content of down-powder and the mechanical ...

Conventional cotton dyeing methods rely on high salt concentrations and consume large amounts of water. To decrease the ecological impact of the textile industry, the development of a green and sustainable dyeing method for cotton fibres is essential. In the present work, ethanol was used to reduce the amounts of salt and water required for cotton dyeing. Cotton yarns were pretreated with alkali and then dyed with six reactive dyes in a 90 : 10 (v/v) ethanol–water mixture. Using various techniques, including transmission electron microscopy, the effects of ethanol on the particle size and zeta potential of the reactive dyes were examined in detail. Compared with conventionally dyed samples, the cotton yarns dyed in the ethanol–water system using the investigated reactive dyes exhibited enhanced exhaustion, total fixation, and colour strength in the absence of salt. Industrial-scale cotton bobbins produced using the developed method showed commercially acceptable levelness and reproducibility. This method affords a substantial reduction in eutrophication potential and wastewater effluent load, which would considerably improve the environmental cost of cotton dyeing processes. This eco-friendly dyeing process has considerable potential for application to a broad range of natural fibres.

Vehicular ad hoc networks (VANETs) support safety and comfortable driving through frequent information exchange among intelligent vehicles. As an open access environment, VANETs are vulnerable to security threats, such as electronic attack and privacy disclosure. In this paper, we propose a misbehavior detection mechanism based on a support vector machine (SVM) and Dempster–Shafer theory (DST) of evidence to resist false message attack and message suppression attack. The proposed mechanism includes data trust model and vehicle trust model. The data trust model uses an SVM-based classifier to detect false messages based on message content and vehicle attributes. The vehicle trust model consists of a local vehicle trust module and a trust authority (TA) vehicle trust module. The local vehicle trust module uses another SVM-based classifier to evaluate whether the vehicle is credible based on the behavior of the vehicle in terms of message propagation. Then, the TA vehicle trust module uses DST to aggregate multiple trust assessment reports about the same vehicle and derives a comprehensive trust value. Simulation results show that Gaussian kernel best fits our models compared with other functions. In addition, the true positive rate of our data trust model is higher than the model based on back propagation neural network. Moreover, our two models are more robust than basic majority voting, weighted voting, and Bayesian inference in terms of true positive rate under various scenarios.

Due to the recent development of cyber-physical systems, big data, cloud computing, and industrial wireless networks, a new era of industrial big data is introduced. Deep learning, which brought a revolutionary change in computer vision, natural language processing, and a variety of other applications, has significant potential for solutions providing in sophisticated industrial applications. In this paper, a concept of device electrocardiogram (DECG) is presented, and an algorithm based on deep denoising autoencoder (DDA) and regression operation is proposed for the prediction of the remaining useful life of industrial equipment. First, the concept of electrocardiogram is explained. Then, a problem statement based on manufacturing scenario is presented. Subsequently, the architecture of the proposed algorithm called integrated DDA and the algorithm workflow are provided. Moreover, DECG is compared with traditional factory information system, and the feasibility and effectiveness of the proposed algorithm are validated experimentally. The proposed concept and algorithm combine typical industrial scenario and advance artificial intelligence, which has great potential to accelerate the implementation of industry 4.0.