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Electromagnetic coil launch is an important branch of electromagnetic launch (EML) technology, which is suitable for launching anti-torpedo torpedo (ATT). This paper focuses on the EML parameters and the interception probability of the EML two ATTs salvo. Based on the launching model of a multi-stage coil launcher, the trajectory model of the ATT and the attacking torpedo, a calculation method for the EML two ATTs salvo parameters is proposed, with the conditions of capture and interception given reasonably. An adaptive particle swarm optimization (APSO) algorithm is proposed to calculate the optimal launching parameters, by designing the adaptive inertia weight and time-varying study factors. According to the analysis of the simulation with Monte Carlo method, EML will improve the interception probability effectively, and the interception probability is affected by the launching range. The results demonstrate good performance of the proposed APSO in calculating EML parameters for the two ATTs salvo in certain combat situation. Implications of these results are particular regarding the command and decision in the anti-torpedo combat.

With the unique characteristics, electromagnetic launch technology is applicable to launch shipborne anti-torpedo torpedo(ATT). This paper aims to establish an analytic model to pre-evaluate the capture probability of the electromagnetic launched ATT. The mathematics model of the multi-stage coilgun and the trajectory of the ATT is established for analysis. The influence factors of the capture probability are analyzed respectively, including the entry point dispersion of the ATT and the position dispersion of the incoming torpedo. Adopting the advanced angle interception mode, the ATT search model is obtained according to the positional relationship, and the course error is synthetically calculated according to the differentiation of implicit function. A geometric method to calculate the integral boundaries of the probability density function is proposed, based on the relative motion of the ATT and the incoming target. To verify the proposed integral model, the digital simulation and comparison is conducted. The results reveal that the variation trends and the calculation value of the proposed analytic model are coincident with the statistic results from Monte Carlo method. And implications of the results regarding the analytic model are discussed.

Due to the influence of many factors, the overpressure–time history load model of vented gas explosions is difficult to describe and is not conducive to further structural design. Based on vented gas explosion test data, this paper obtains three typical overpressure-time history curves and puts forward a new semi-empirical model— double hump model that considers gas concentration and venting pressure, and gives a formula for peak pressure and overpressure–time history model. The scientificity of the model is then verified by the total impulse in the load. The model is able directly reflect the load characteristics, provide reference for calculating key parameters of a vented gas explosion and provide information on the structural response under the load. The model thereby has the potential to help reduce the impact of gas explosion disasters.

Ammonia is a vital intermediate in the hydrogen desorption process of Metal-N-H system. KH has strong reactivity with NH3 to form KNH2. We speculate that KNH2 is also an intermediate formed during hydrogen desorption of the potassium-doped M-N-H systems. In this research, the dehydrogenation performance of the KNH2-doped LiNH2 and LiH composition was first studied. Compared with the broad dehydrogenation curve of the composite material of LiNH2 and LiH without the catalyst, the dehydrogenation curve of 0.05 mol KNH2-doped composite material was significantly narrowed. The initial and peak dehydrogenation temperature of the composite to which 0.05 mol of KNH2 was added was lowered remarkably. Besides, the cyclic dehydrogenation properties of the LiNH2 and LiH system was also significantly enhanced by the introduction of KNH2. The cyclic conversion of KNH2 to KH is the main reason for the enhancement of the hydrogen evolution performance of the LiNH2–LiH system doped with KNH2. We found the KNH2-doped Li–N–H system exhibits similar dehydrogenation property with that of the KH-doped Li–N–H system. This work proves that KNH2 plays a key role in improving the hydrogen desorption performances of the potassium-doped M-N-H systems.

In this paper, we present a chaos-based scheme which allows for bidirectional transmission and recovery of message by simultaneously changing the feedback phase and coupling phase. In our scheme, three semiconductor lasers are mutually connected, and in each link the partially transparent mirror is used to supplement the degree of freedom to produce the chaotic carrier, moreover, the coupling between semiconductor laser 1, laser 2 and laser 3 through a partially transparent mirror induces the delay and chaos dynamics. We numerically have proven that three lasers can be fully in synchronization, and the message which is introduced by ON/OFF phase shift keying on the ends of each laser can be successfully encoded and decoded, at last the system can realize the bidirectional transmission of message between three parties.

This study examined the course of mitophagy following cerebral ischemia with reperfusion and the role of the PTEN-induced kinase 1 (PINK1)/Parkin/p62 signalling pathway. The middle cerebral artery of male Sprague-Dawley rats was occluded for 90 min and was followed by different time-points of reperfusion. Cerebral infarct areas were detected by 2,3,5-triphenyl tetrazolium chloride staining, while brain damage was observed by haematoxylin and eosin staining. Levels of LC3, Beclin1 and LAMP-1 were estimated by western blots. LC3B location was observed in various cells in the neurovascular unit. In addition, PINK1 accumulation in damaged mitochondria and Parkin/p62 mitochondrial translocation were investigated by double immunofluorescence staining. Finally, the levels of PINK1, Parkin and p62 expression in mitochondrial fractions were estimated by western blots. Cerebral ischemia with different time-points of reperfusion resulted in infarct in the territory of the middle cerebral artery accompanied by overall brain damage. In addition, we found up-regulation of LC3B, Beclin1, and LAMP-1, as well as mitophagy activation after reperfusion, with peak expression of these proteins at 24 h after reperfusion. Electron microscopy and immunofluorescence indicated that LC3B was primarily located in neurons, although lower levels of expression were found in astrocytes and even less in vascular endothelial cells. Moreover, significant increases in PINK1 accumulation in the outer membrane of mitochondria and increased Parkin/p62 mitochondrial translocation were shown at 24 h after reperfusion. These findings suggest that the PINK1/Parkin/p62 signalling pathway was involved in the pathophysiological processes following ischemia and reperfusion.

The dissolved oxygen (DO) content of the ocean provides potential evidence and clues for the waxing and waning of marine productivity, ocean circulation, global climate change, and the evolution of ecological communities. On the basis of the analysis of the Benthic Foraminiferal Oxygen Index (BFOI), the percentage of epifaunal benthic foraminifers, and the redox-sensitive trace elements (Mo/Al) in Core MD12-3432, we reconstruct the evolution of deep water DO content in the northern South China Sea (SCS) during the past 400 ka and discuss the mechanisms of variable DO content. The results show that the changes of BFOI, Mo/Al, and the percentage of epifaunal benthic foraminifer present a similar pattern, which may reflect the variations of the DO content in seawater since 400 ka. Both variations in BFOI and Mo/Al indicate that the DO content was high during most time of marine isotope stage (MIS) 11 to mid-MIS 6, then decreased in late-MIS 6, and remained stable in MIS 5. It increased in MIS 4 and decreased until MIS 2, and then rose again. The non-synchronous variations between bottom water DO and benthic foraminiferal δ18O indicate that the DO content is not controlled by glacial-interglacial cyclic environmental variations. Comparing the biomarker productivity index with the DO content of water, we find that the DO content is affected mainly by productivity. Bulimina, Uvigerina and Chilostomella oolina are high productivity species. The accumulation rates of Bulimina and Uvigerina are higher during 61–15 kyr interval, but the accumulation rate of C. oolina is higher during 168–130 kyr. The results infer that different intensity of primary productivity and DO during these two periods. The DO and phytoplankton total (PT) show the opposite relation, which also indicates that the DO is affected by primary productivity, and the combined action of productivity and DO decides the growth of Bulimina, Uvigerina, and C. oolina. Besides the influences of productivity, the change of DO in the ocean is also affected by oceanic circulation.

Late Pennsylvania–Early Permian carbonate mud-mounds exposed in the Shangdan section, Inner Mongolia, are commonly massive, showing depositional relief, and are distinct from the thin- to medium-bedded limestones of intra-mounds. Based on the various proportions of lithofacies, four types of mud-mounds are recognized: MM-A (type A carbonate mud-mound) and B (type B carbonate mud-mound) consist of massive lime mudstone and massive wackestone (Subfacies B), respectively; MM-C (type C carbonate mud-mound) are composed of massive wackestone (Subfacies B) in the lower parts, analogous to MM-B, and massive wackestone (Subfacies A) and boundstone in the upper parts, similar to MM-D (type D carbonate mud-mound). Carbonate mud-mounds are deposited in low-energy settings on a ramp, likely below fair-weather wave base, where the depositional settings of MM-A, B, C and D have a shallowing-upward trend. Carbonate mud-mounds have diverse origins of lime mud: allochthonous lime mud in MM-A; lime mud produced by the disintegration of phylloid algae in MM-B, C and D; lime mud linked to cyanobacterial activity in MM-D and the upper parts of MM-C. Different from MM-A and B, which were formed only by mechanical accumulation, MM-C and D resulted from the combinations of mechanical accumulation and microbial binding and solidifying. MM-A, B, C and D significantly expand the global spectrum of Late Pennsylvania–Early Permian carbonate mounds.

The development of inert additive-doped CaO-based CO2 adsorbents is a promising method to obtain efficient CO2 adsorbents, while multiple programs are frequently involved, the organic solvent is often used, and CO2 is sometimes released in the process of preparation. In this study, we first report that inert additive-doped CaO-based adsorbents can be synthesized in one pot by the mechanochemical hydrogenation reduction of CaCO3 producing methane and avoiding CO2 emission. The prepared CaO@C and CaO@MgO@C composites are high-performance CO2 adsorbents with high CO2 adsorption capacity and superior cycling stability. The results show that the CO2 capture capacities of the CaO@C and CaO@MgO@C composites are 19.14 and 14.53 wt% higher than that of the BM-CaO (37.07 wt%), respectively, at 650 °C carbonation for 2 h. Notably, the activity losses of the CaO@C and CaO@MgO@C composites after 30 cycles are about 47.93 and 29.33%, which are much lower than that of the BM-CaO (60.39%). The performance of the CaO@C and CaO@MgO@C adsorbents is comparable to that of adsorbents synthesized by the conventional methods, but this work provides novel, simple, solution-free, and sustainable strategies to synthesize effective CaO-based CO2 adsorbents in one pot.

Background Isolating of primary motor neurons from animal embryos is critical for the study of neurological disease including mechanistic discovery and therapeutic development. Density gradient centrifuge taking advantage of the buoyant of motor neuron permits the enrichment of motor neurons. Despite the metrizamide, an OptiPrep medium has been introduced to separate the motor neurons by gradient centrifuge. New method We hereby used single density gradient of OptiPrep medium to isolate the spinal motor neurons from the fetal mouse. Results Single density gradient of OptiPrep medium is effective to isolate spinal motor neurons from the fetal mouse. The immunofluorescence staining analysis showed that the purity of cultured motor neurons at 72 h was between 90% and 95%. Comparison with existing method Four gradients of OptiPrep medium have been previously used to isolate the motor neurons from spinal cord of mouse. In this study, the single gradient of OptiPrep medium was demonstrated to effectively isolate spinal motor neurons from the fetal mouse. Conclusions The single gradient of OptiPrep medium is enough to produce high purity of spinal motor neurons from the fetal mouse.

A total of 16 full-scale in-situ tests were carried out to investigate the performances of unreinforced clay brick masonry walls subjected to vented gas explosions. The pressure-time histories of vented gas explosions, displacement-time histories and failure modes of wall specimens in each test were recorded and analyzed. A detailed micro model for masonry wall was developed in the finite element software LS_DYNA 971. The numerical model was validated with the test data and intensive numerical simulations were conducted to explore the influences of boundary condition, bonding pattern and thickness of masonry walls on their performances against vented gas explosions. The results show that the classical yield-line modes dominate failure patterns of masonry walls subjected to vented gas explosions and the dynamic responses of masonry walls are determined by the peak value of overpressure. It is found that boundary condition and wall thickness have great influence on the performance of masonry walls, while bonding pattern has relatively limited influence on its performance. In addition, the recorded gas explosion loads were compared with the predictions from the conventional TNT equivalency method and the methods specified in NFPA 68 and EN 14994. The results indicate both NFPA 68 and EN 14994 approaches give very conservative predictions of peak pressure from gas explosions. The TNT equivalency method also overestimates the peak pressure and predicts a load profile which is significantly different from the test data.

A total of nine full-scale in-situ tests were carried out to investigate the performances of autoclaved aerated concrete (AAC) masonry walls subjected to vented gas explosions. The testing data including overpressure time histories of vented gas explosions, displacement time histories, and damage characteristics of AAC masonry walls in each test were recorded and analysed. It was found that the responses of masonry walls mainly depend on the peak value of overpressure and couple with the time history of gas explosion loads. Typical one-way or two-way flexural mode dominates the failure of AAC walls under vented gas explosions. A detailed micro model for masonry walls was developed in LS-DYNA, incorporating material parameters that were obtained from material tests. The accuracy of numerical model in predicting the responses of masonry walls was verified with the testing data. Parametric studies were conducted to explore the influences of block strength, boundary condition and wall thickness on the performances of masonry walls. The results reveal both wall thickness and boundary condition have significant influences on the response of the masonry wall while block strength has limited effect on its performance. The testing data were compared with the analytical predictions by using design code UFC 3-340-2 and equivalent single-degree-of-freedom (SDOF) methods developed respectively by Biggs and Morison. The results indicate that these predictions on one-way specimens agree well with the testing data, while the performance of two-way specimens is overestimated by using these three methods.

9 batches of unconfined methane-air deflagration tests were conducted to investigate the influential factors on the deflagration load. The methane-air mixture was filled in the cubic tents with different volumes of 1 m3, 8 m3and 27 m3. Methane concentrations varied from 7.5% to 11.5%, covering both lean and rich combustion regimes. The ground overpressure was recorded by using the piezoresistive sensors. An ideal film was validated before the tests. The effects of the methane concentration and gas volume on the deflagration load were analyzed. Based on the results, a new prediction model for the unconfined methane-air deflagration load was proposed. In addition, the model was compared with some existing models.

Unlike fungi, which have a universally accepted barcode marker, universal primers still lack in myxomycetes. Typically, DNA barcode primers were designed based on comparing existing myxomycetes sequences and targeting the conserved regions. However, the extreme genetic diversity within major myxomycetes groups and the frequent occurrence of group I introns have made the development of universal DNA barcode a severe challenge. The emergence of next-generation sequencing provides an opportunity to address this problem. We sequenced the mixed genomic DNA of 81 myxomycetes and extracted the SSU gene's reads using next-generation sequencing. After alignment and assembly, we designed a set of SSU primers that matched all potential SNPs, avoided all known group I intron insertion sites, and were highly conserved between major myxomycetes orders. This set of SSU primers has the potential to become one of the universal primer combinations. Due to the high genetic divergence caused by long and complicated evolutionary histories, the lack of universal barcode primers is common in protists. Our research provides a new method to solve this problem.

The formation of urea linkages is a limitation to the application of solid amine CO2 adsorbents. Therefore, the development of solid amine adsorbents with resistance to urea linkage formation has attracted much interest over the last 5 years. In this study, we developed a facile method for synthesizing solid amine adsorbents with effective resistance to urea linkage formation. For the first time, metal nitrates were used to modify amorphous nano SiO2 to support polyethyleneimine (PEI). Three metal nitrates were investigated: aluminum, magnesium, and zinc nitrates. A series of adsorbents were prepared by controlling the mass ratios of metal nitrates and nano SiO2. After 50 cycles of adsorption–desorption tests, adsorbing at 75 °C under 15 % CO2 balanced with N2 and desorbing at 130 °C under pure CO2, Al-20%@SiO2-PEI, Al-15%@SiO2-PEI, Al-10%@SiO2-PEI, Zn-10%@SiO2-PEI, and Mg-10%@SiO2-PEI lost only 2.6 %, 4.0 %, 5.2 %, 15.9 %, and 28.8 % of their original CO2 adsorption capacities, respectively. However, SiO2-PEI, calcined SiO2-PEI, and Al-5%@SiO2-PEI lost 42.9 %, 48.6 %, and 49.6 %, respectively. By combining the infrared spectra of all the adsorbents through cyclic adsorption–desorption tests, inhibitory effects on urea linkage formation were proven for Al-20%@SiO2-PEI, Al-15%@SiO2-PEI, Zn-10%@SiO2-PEI, and Mg-10%@SiO2-PEI, and especially for Al-10%@SiO2-PEI. Through a relatively comprehensive analysis, we found that a desirable amount of metal nitrates could modify nano SiO2 samples and their corresponding adsorbents possessed a stronger H2O binding ability at 130 °C. The retained H2O could act as an inhibiting agent for the inhibition of urea linkage formation.

Fe–N–macrocycles have been viewing as the most promising catalyst for CO2ER. It is of great importance to explore the performance of composite CuFe–N–C in CO2ER. Fe-Cu–BTT precursor was prepared by introducing the ferrous ion to a microporous N-rich MOF. It exhibits a lower plateau temperature of 800 ℃ than the prototype. The pyrolysis product of FexCu–N–C increases the selectivity of CO2-to−CO due to the increase of the BET surface area, the total pore volume, and the Fe–Nx sites, as well as a lower density of Cu NPs in the carbon matrix. The Fe0.07Cu–N–C800 exhibits the highest FECO of 48.5 %.