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Polymerised styrene-butadiene rubber (SBR) 1502 is one of the most common petrochemical products. During the identification of fire evidence, the combustion residues of SBR 1502 highly interfere with the identification of gasoline, a fire accelerant. By conducting thermogravimetric–differential scanning calorimetry (TG-DSC) experiments at various oxygen concentrations (0, 14, and 21 vol.%), the TG-DSC combustion characteristic behaviour of SBR 1502 was investigated. Gas chromatography–mass spectrometry was used to examine the combustion residues at different stages. The results indicated a lack of 2,3-dimethylnaphthalene among the combustion residue of SBR 1502 at the oxygen concentration of 0 and 14 vol.%, thus effectively avoiding the interference of this combustion residue in gasoline identification. The results of the quantitative analysis revealed aromatic hydrocarbon components as the most interfering components for all oxygen concentration and temperature. The combustion residues of SBR 1502 at different oxygen concentrations and combustion stages exhibited different degrees of interference in gasoline identification. Therefore, qualitative and quantitative analyses (hierarchical clustering analysis) were employed to eliminate interference from SBR 1502 in gasoline identification. The results provide theoretical support during the fire identification process. [ABSTRACT FROM AUTHOR]

Automotive powertrain mounting systems (PMSs) may exhibit hybrid interval-random (HIR) uncertainties in engineering practice. In HIR case, the uncertain parameters of PMSs are characterized as the random variables with interval distributions. A comprehensive methodology is proposed for the design optimization of the PMSs involving HIR uncertainties in this study. The hybrid interval-random perturbation central difference method (HIRP-CDM) is firstly derived to calculate the uncertain responses of PMSs, in which HIR uncertainties are addressed by twice perturbation analyses and twice central difference analyses. Meanwhile, the hybrid interval-random Monte Carlo method is presented as a reference method. Then, reliability assessment models are constructed to evaluate the probability intervals of system inherent characteristics satisfying design requirements. Next, a design optimization model is formulated to explore the optimal design of PMSs. The expectation intervals and variance intervals of system inherent characteristics are taken to create optimization objective, and the minimal probabilities of system inherent characteristics meeting requirements are utilized to establish reliability constraints. Both robustness and reliability are considered in the optimization, and the optimization can be simplified with the aid of HIRP-CDM. The effectiveness of the proposed methodology is finally demonstrated by the numerical example. [ABSTRACT FROM AUTHOR]

In some special engineering cases, the lower and upper bounds of uncertain parameters are appropriately quantified as fuzzy variables instead of deterministic values. To address such cases, a possibility-based robust design optimization (PBRDO) framework is suggested for the hybrid uncertain structures with fuzzy-boundary interval (FuBI) variables. Firstly, an optimization model with FuBI variables is established where FuBI uncertainties exist in both the objective and constraint functions. The so-called dual robust design is presented and it is adopted to create the optimization objective. The first robust design aims to handle fuzziness while the second one attends to tackle interval property. The failure possibility is employed to construct the optimization constraints in possibilitic context. Then, the fuzzy-boundary interval Taylor series-central difference method (FITS-CDM) is derived to manage FuBI uncertainties and calculate the optimization objective efficiently. Next, the target performance approach (TPA) is employed to process the possibilistic constraints and the simplified constraints can be easily solved by FITS-CDM. The nested-loop PBRDO with FuBI variables can be simplified to a single-loop one based on FITS-CDM and TPA. Finally, the effectiveness of the proposed optimization approach on dealing with FuBI uncertainties is demonstrated by three examples. [ABSTRACT FROM AUTHOR]

During fire investigation, gasoline, as a common accelerant, is produced by petroleum cracking. However, the pyrolysis residues of other petrochemicals may interfere with gasoline identification. Polymerised styrene butadiene rubber (SBR) 1502 has combustion characteristics highly consistent with those of gasoline, thus having a great effect on gasoline identification. This study investigated the pyrolysis process of SBR 1502 by using thermogravimetric–differential scanning calorimetry (TG–DSC) and gas chromatography–mass spectrometry (GC–MS) to examine the residues during combustion stages, including pyrolysis and nonpyrolysis stages. The results indicated that 2,3-dimethylnaphthalene in the pyrolysis residues of SBR 1502 in pyrolysis stages 2 and 3 was lacked. However, when SBR 1502 only undergoes the first pyrolysis stage or even earlier (Nonpyrolysis stage), the characteristic components in the residue are similar to gasoline. In addition, mathematical methods were applied to analyse relevance and differences between SBR 1502 and gasoline. The conclusion was that the Pearson product-moment correlation was > 0.990, which may interfere with the identification, and principal component analysis could efficiently distinguish them. The current results can provide an accurate and feasible basis for fire investigation. [ABSTRACT FROM AUTHOR]

In this study, a hybrid uncertainties-based analysis and optimization method is presented for the designs of the powertrain mounting system (PMS) involving mixed uncertainties. In the presented method, the PMS parameters with sufficient data are treated as random variables, while those with limited information are defined as interval variables. Then, an uncertainty-based analysis method called as hybrid interval-random perturbation-central difference method (HIRP-CDM), is proposed to compute the hybrid interval-random outputs of the inherent characteristics of the PMS in concerned directions. In addition, the hybrid interval-random-Monte Carlo method (HIR-MCM) is developed to verify the computational accuracy of HIRP-CDM. Next, an optimization model mixed uncertainties is built up for the PMS design based on HIRP-CDM, in which the hybrid intervalrandom outputs of the concerned inherent characteristics are adopted to construct the design objective and constrains. The complex optimization problem can be effectively settled by means of HIRP-CDM. The effectiveness of the presented method is verified by a numerical example. [ABSTRACT FROM AUTHOR]

Coal spontaneous combustion (CSC) is a global, long-standing thermal hazard in coal mining that causes serious environmental damage, particularly in developing countries. Ionic liquids (ILs) are environmentally friendly, green, economical, and a new type of fire-preventing material that inhibits coal oxidation and alleviates thermal production. In this study, 1-butyl-3-methyl imidazole tetrafluoroborate ([BMIM][BF4]) and 1-butyl-3-methyl imidazole ([BMIM][I]) at various mass ratios (0.0, 0.5, 2.0, 5.0, and 10.0 mass%) were used to treat three types of coal (lignite, 1/3 coking coal, and anthracite) for CSC. The combustion-mass loss and thermal release rate of ILs treated relative to untreated coal samples were investigated using a synchronous thermal analyzer, and the optimal addition mass ratio of ILs was predicted. Not only do ILs have the most efficient inhibiting effect, but they also consider the economic benefit. Per thermogravimetric-differential scanning calorimetry, for the content of 5.0 mass% [BMIM][BF4], the inhibiting effect is favorable for universal applications. In addition, coal samples treated with 5.0 mass% [BMIM][BF4] were subjected to programmed-temperature heating experiment testing. The oxygen consumption rate, inhibiting effect, as well as apparent activation energy, were determined. The inhibiting effect at 120.0–150.0 °C was the most obvious, which provided the basis of the application for CSC prevention. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) are a type of environmentally friendly solvents. Several studies have proven that ILs can inhibit the spontaneous combustion of coal (SCC). In this study, a synchronous thermal analyzer was used to analyze the effects of the imidazolium-based IL [BMIM][BF4] on coal of three metamorphic grades. A coal sample exhibiting the optimal inhibiting result was selected to investigate the effect of the oxygen concentration on IL inhibition. The results revealed that the influence of IL on the mass loss process of the three metamorphic grades of coal varied considerably. High inhibition was observed in lignite. However, the IL promoted the mass loss process in 1/3 coking coal and anthracite. The IL delayed the ignition temperature of lignite by 42 °C, whereas those of 1/3 coking coal and anthracite were advanced by 10 and 8 °C, respectively. Furthermore, the initial exothermic temperature of the three treated coal samples was higher than those of the raw coal samples. Compared with the raw coal samples, the heat released per gram of lignite, 1/3 coking coal, and anthracite was reduced by 1142, 353, and 226 J, respectively. The results indicated that the IL had a prominent inhibiting effect on the exothermic properties of the three coal samples, and the inhibiting effect decreased with an increase in the metamorphic grade of coal. Moreover, the oxygen concentration did not alter the inhibition properties of the IL on the SCC. However, the inhibiting effect weakened as the oxygen concentration decreased. [ABSTRACT FROM AUTHOR]

Coal spontaneous combustion (CSC) is an extremely complex physical and chemical reaction between coal and oxygen, and it results in the gradual accumulation of thermal energy that eventually produces conditions that are favorable for combustion. Ionic liquids (ILs) inhibit coal oxidation and reduce the amount of heat that is produced. A synchronous thermal analyzer was used to examine the effects of imidazolium-based ILs on bituminous coal from two sources. The results revealed that with the anion [BF4]−, the inhibiting effect of [BMIM]+ was stronger than that of [EMIM]+. Moreover, with the cation [BMIM]+, the inhibiting effects of [BF4]− were stronger than that of [I]− and [NO3]−. The inhibiting effects of the ILs on CSC were estimated using the Ozawa-Flynn-Wall method, which relates the apparent activation energy to the degree of conversion. The inhibiting effect of [BMIM][BF4] offers a basis for effectively preventing CSC and is favorable for universal application. [ABSTRACT FROM AUTHOR]

A mortality rate higher than 90 % was observed in a larva-rearing facility for Pacific cod, Gadus macrocephalus, in China. Larvae showing clinical signs of infection were collected. Initial suspicion of nervous necrosis virus (NNV) infection was confirmed by sequencing, absolute quantification real-time PCR (A-qPCR), and electron microscopy. The nucleotide sequence of RNA2 was 1,375 bases long (GenBank no. KM576685), coding for a single ORF corresponding to the capsid protein from residues 21 to 1034. Phylogenetic analysis of the capsid protein sequence showed that PCNNV belongs to the barfin flounder NNV (BFNVV) genotype. An amino acid sequence alignment revealed 39 differences between the cold- and warm-resistant viral groups, suggesting that PCNNV evolved under temperature selection. The 3-D structure of the predicted capsid protein was modeled to identify potential epitopes, and the gene was expressed in Escherichia coli, yielding a protein with a molecular mass of 55 kDa. During PCNNV outbreaks, the viral copy number was found to reach 10 per ng of total RNA, which could be considered the lethal copy number of NNV in cod. The gonads, eggs, fertilized eggs and asymptomatic cod fry were all positive for PCNNV, indicating viral vertical transmission as the main source of the viral load. The amount of virus in the apparent healthy fry or survivors seemed to decrease gradually with development. These results might lead to efficient diagnostic methods to help farmers select NNV-free broodfish for cod breeding. [ABSTRACT FROM AUTHOR]

Perovskite oxides and heterojunctions have attracted much attention due to their multifunctional properties of electricity and optics and magnetic as well as the very good chemical and thermal stability. In this brief review, we describe the novel progress of researches in the optical characteristic, including ultrafast photoelectric effects of picosecond order in perovskite oxide single crystals, thin-films and heterojunctions, high-sensitive photovoltages, the enhanced transient lateral photovoltages in perovskite oxide thin-films and heterojunctions, and the high-sensitive ultraviolet (UV) photodetectors based on perovskite oxides. The recent advances present in this paper not only could stimulate theoretical studies on the mechanism but also would open up the possibilities in the developments of optoelectronic devices based on perovskite oxides and heterojunctions. [ABSTRACT FROM AUTHOR]

Cyclic voltammetry was used to investigate the reaction of erythromycin (EM) with dissolved oxygen on gold nanoparticle-modified electrodes prepared via electrodeposition. A well-defined reduction peak at −0.420 V and a reoxidation peak at −0.055 V were observed. With the addition of EM into the NaOH solution containing dissolved oxygen, the oxidation peak at −0.055 V was still indiscernible. However, a new oxidation peak at 0.200 V appeared, which suggests the interaction between EM and dissolved oxygen. Therefore, this method can be used for the analysis of EM in tablets. The present method is simple, reproducible, and does not require complex analytical instruments. [ABSTRACT FROM AUTHOR]

The effect of Cd doping on structure and superconductivity in Mg0.5Cd0.5B2 fabricated by a solid-state reaction at ambient pressure has been investigated. The resulting changes in crystal structure, superconducting transition temperature Tc and critical current density Jc are characterized by X-ray diffraction, dc magnetization, electrical resistance, and magnetic measurements. It reveals that Cd does not occupy the atomic Mg sites in the MgB2 crystal structure, but merely reacts with Mg and forms a MgCd3 phase. It is striking to note that although the nonsuperconducting phase MgCd3 is as high as about 67 vol.% in Mg0.5Cd0.5B2, the Tc of the doped sample drops only by about 1 K. Most important, a surprising improvement of Jc of 5.0 × 105 A/cm2 (5 K, 0 T) has been achieved in Mg0.5Cd0.5B2. It is suggested that the improvement in Jc in Mg0.5Cd0.5B2 is primarily due to pinning effects induced by MgCd3. Also, it is thought that MgCd3 may fill up gaps among grains in MgB2 and produce better grain linkage, which may be another source of improvement in Jc in Mg0.5Cd0.5B2. [ABSTRACT FROM AUTHOR]

Using nystatin-perforated whole-cell recording configuration, the modulatory effect of N-methyl-D-aspartate (NMDA) on γ-aminobutyric acid (GABA)-activated whole-cell currents was investigated in neurons freshly dissociated from the rat sacral dorsal commissural nucleus (SDCN). The results showed that: (i) NMDA suppressed GABA-and muscimol (Mus)-activated currents (Igaba and IMus), respectively in the Mg2+-free external solution containing 1 μmol/L glycine at a holding potential ( V H ) of −40 mV in SDCN neurons. The selective NMDA receptor antagonist, D-2-amino-5-phosphonovaleric acid (APV, 100 γmol/L), inhibited the NMDA-evoked currents and blocked the NMDA-induced suppression of Igaba; (ii) when the neurons were incubated in a Ca2+-free bath or pre-loaded with a membrane-permeable Ca2+ chelator, BAPTA AM (10 μmol/L), the inhibitory effect of NMDA on IGAba disappeared. Cd2+ (10 μmol/L) or La3+ (30 μmol/L), the non-selective blockers of voltage-dependent calcium channels, did not affect the suppression of Igaba by NMDA application; (iii) the suppression of IGAba by NMDA was inhibited by KN-62, a calcium/calmodulin-dependent protein kinase II (CaMKII) inhibitor. These results indicated that the inhibition of GABA response by NMDA is Ca2+-dependent and CaMKII is involved in the process of the Ca2+-dependent inhibition. [ABSTRACT FROM AUTHOR]