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Among the all-solid-state lithium metal batteries, it is remarkably of importance to realize the superior compatibility and stability of electrode/electrolyte solid-solid interface. A direct viewer of microevolution will induce an in-depth fundamental insight into the reaction mechanisms and interfacial regulations during the cycling operation. Herein, using in situ electrochemical atomic force microscopy combined with optical microscope imaging techniques, we present a dynamic observation of interfacial processes and structural evolution of solid-state electrolyte mediated by lithium salts in a working all-solid-state lithium-sulfur battery (ASSLSB) with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), lithium bis(fluorosulfonyl) imide (LiFSI) and LiTFSI-LiFSI binary-salts. The in-situ monitoring shows that the binary-anion polymer-rich composite electrolytes could well achieve self-regulation in the interfacial compatibility and the side reaction of dissolved polysulfides in enabling ASSLSBs. Moreover, it indicates the anion dependence of ion transportation, interphasial wettability and labile decomposition of electrolytes for ASSLS systems, which determines the dynamic evolution and systematically proposes the corresponding interfacial degradation mechanisms. The in situ visualization provides a direct understanding of ASSLS electrochemical reaction mechanisms and interphasial properties, which will efficiently guide one to explore strategies to develop the optimum all-solid-state systems.

Single-crystalline Ni-rich cathode (SC-NCM) has attracted increasing interest owing to its greater capacity retention in advanced solid-state lithium batteries (SSLBs), while suffers from severe interfacial instability during cycling. Here, via atomic layer deposition, Li

An intensive understanding of the Li-ion transport mechanism in solid-state-electrolytes (SSEs) is crucial for the buildup of industrially scalable solid-state batteries. Here, we report on the charge distribution near the electrode/SSE interface and the Li-ion transport in solid-state-electrolyte Li7La3Zr2O12 (LLZO) via real-time in situ electron holography and electron energy loss spectroscopy (EELS) monitoring in a working cell model. The reconstructed phase image unravels the behavior of Li ions beneath the electrode during the charging process. The inhomogeneous accumulation occurs at charging, and the Li ions remained there after the reversal operation. Grain boundary (GB) may be the negative influence on the ion conductivity. These findings provide an in-depth understanding of the interfacial mechanism, and thus improve the optimized design of solid-state batteries.

Sulfide-based solid-state electrolytes (SSEs) matched with alloy anodes are considered as promising candidates for application in all-solid-state batteries (ASSBs) to overcome the bottlenecks of the lithium (Li) anode. However, an understanding of the dynamic electrochemical processes on alloy anode in SSE is still elusive. Herein, in situ atomic force microscopy gives insights into the block-formation and stack-accumulation behaviors of Li precipitation on an Li electrode, uncovering the morphological evolution of nanoscale Li deposition/dissolution in ASSBs. Furthermore, two-dimensional Li-indium (In) alloy lamellae and the homogeneous solid electrolyte interphase (SEI) shell on the In electrode reveal the precipitation mechanism microscopically regulated by the alloy anode. The flexible and wrinkle-structure SEI shell further enables the electrode protection and inner Li accommodation upon cycles, elucidating the functional influences of SEI shell on the cycling behaviors. Such on-site tracking of the morphological evolution and dynamic mechanism provide an in-depth understanding and thus benefit the optimizations of alloy-based ASSBs.

Zinc finger proteins (ZFPs) are a class of transcription factors that contain zinc finger domains and play important roles in growth, aging, and responses to abiotic and biotic stresses. These proteins activate or inhibit gene transcription by binding to single-stranded DNA or RNA and through RNA/DNA bidirectional binding and protein-protein interactions. However, few studies have focused on the oxidation resistance functions of ZFPs in insects, particularly Apis cerana. In the current study, we identified a ZFP41 gene from A. cerana, AcZFP41, and verified its function in oxidative stress responses. Real-time quantitative polymerase chain reaction showed that the transcription level of AcZFP41 was upregulated to different degrees during exposure to oxidative stress, including that induced by extreme temperature, UV radiation, or pesticides. In addition, the silencing of AcZFP41 led to changes in the expression patterns of some known antioxidant genes. Moreover, the activities of the antioxidant enzymes catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), and glutathione S-transferase (GST) in AcZFP41-silenced honeybees were higher than those in a control group. In summary, the data indicate that AcZFP41 is involved in the oxidative stress response. The results provide a theoretical basis for further studies of zinc finger proteins and improve our understanding of the antioxidant mechanisms of honeybees.

Intensive understanding of the surface mechanism of cathode materials, such as structural evolution and chemical and mechanical stability upon charging/discharging, is crucial to design advanced solid-state lithium batteries (SSLBs) of tomorrow. Here, via

The geogrid can be damaged in the process or during construction if sufficient care is not exercised. In this study, the numerical software-FLAC was adopted to investigate the responses of pre-damaged geogrids with rectangular apertures when subjected to a uniaxial tensile load at different directions relative to the orientations of ribs in air. To simulate the combined loss of ribs and junction strength, specimens were pre-damaged by reducing certain amount of stiffness of the geogrid ribs. The geogrid ribs were modeled using beam elements jointed rigidly at nodes and subjected to tension in one direction. The numerical study demonstrated that the pre-damaged geogrid with rectangular apertures had similar responses when it was subjected to tension at the loading directions. The pre-damaged geogrids under 30° tension are the most sensitivity to the damage. With the increase of the degree of damage, the tensile strengths decreased relative quickly. An increase of the degree of installation damage of ribs decreased the tensile strength/stiffness of the geogrid with rectangular apertures. A higher reduction factor RFID due to installation damage is suggested when the geogrid is subjected to 30° tension relative to the orientation of ribs. Keywords: Geogrid with rectangular apertures, Installation damage, Tensile strength retained, Reduction factor, Tensile strength distribution

Background The positive effects of nitrogen fertilization on the performance of phytophagous insects have been reported extensively; the physiological and molecular basis involved, however, is largely unclear. Here, we test experimentally whether enhancement of juvenile hormone (JH) is responsible for the increased weight and fecundity of pea aphid (Acyrthosiphon pisum) under nitrogen fertilization. Results Aphids fed on Medicago truncatula with nitrogen fertilization have a greater amino acid content, higher weight at the fourth instar and adult stage, and produce more offspring than those without nitrogen fertilization. Furthermore, nitrogen fertilization upregulates the transcripts of JH biosynthesis-related genes and increases JH titre at the fourth instar and adult stage, suggesting that JH is involved in the positive responses of aphids to nitrogen fertilization. Application of 100 ng JH increases adult weight and fecundity in aphids fed on M. truncatula without nitrogen fertilization. Conversely, impairing JH signalling by pharmacologically inhibiting the target of rapamycin pathway or by knocking down JH biosynthetic gene decreases adult weight and fecundity in aphids fed on M. truncatula with nitrogen fertilization, whereas application of JH rescued the phenotype. Conclusion The increased JH titre at the fourth instar and adult stage is required for the increases of weight and fecundity of A. pisum under nitrogen fertilization. © 2018 Society of Chemical Industry.

The epidemicity of bacteria facultatively associated with eukaryotes, involves not only housekeeping genes but also genes linked with the pathogenesis and symbiosis. Here, by characterizing both housekeeping (rpoB and 16S rRNA gene) and nodulation (nodD) genes, we explore processes shaping epidemic patterns of facultative microsymbionts from rhizosphere soils of faba bean in three ecoregions. Although total bacterial communities in rhizosphere were not significantly differentiated across ecoregions, rpoB amplicon sequencing uncovered that Rhizobium laguerreae and Rhizobium anhuiense were predominant in different samples with contrasting pH or salt content. However, R. anhuiense can outcompete R. laguerreae in certain sterilized soils where R. laguerreae originally dominated, and viceversa. Contrasting bacterial taxa associated with either R. laguerreae or R. anhuiense in soils. The biogeographical pattern of nodD was more clear than that of rhizobial species in both rhizosphere soils and nodules. Competitive nodulation experiments demonstrated a hierarchical selection on nodD genotypes and their genomic backgrounds by faba bean cultivars. Taken together, abiotic and biotic factors in soils and the selection by legume hosts are either indirectly or directly involved in shaping rhizobial species-level taxonomic biogeography, which however cannot be used to infer spatial patterns of nodulation gene.

The ureido substituted imidazolium bromides (code M-n) were synthesized and their anti-corrosion performance on A3 steel in 5 M HCl solution was studied by weight loss test, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization. The experimental results reveal that the inhibitor are efficient mixed type corrosion inhibitors, and their inhibition efficiencies increase with increasing the concentration and alkyl chain. Thermodynamic parameters were calculated and discussed, indicating the adsorption of M-n on steel surface obeys the Langmuir adsorption isotherm and spontaneous exothermic process. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and quantum chemistry calculation further confirm the existence of an effective protective film of M-n on A3 steel surface.

Receiving nodulation and nitrogen fixation genes does not guarantee rhizobia an effective symbiosis with legumes. Here, variations in gene content were determined for three Sinorhizobium species showing contrasting symbiotic efficiency on soybeans. A nitrate-reduction gene cluster absent in S. sojae was found to be essential for symbiotic adaptations of S. fredii and S. sp. III. In S. fredii, the deletion mutation of the nap (nitrate reductase), instead of nir (nitrite reductase) and nor (nitric oxide reductase), led to defects in nitrogen-fixation (Fix- ). By contrast, none of these core nitrate-reduction genes were required for the symbiosis of S. sp. III. However, within the same gene cluster, the deletion of hemN1 (encoding oxygen-independent coproporphyrinogen III oxidase) in both S. fredii and S. sp. III led to the formation of nitrogen-fixing (Fix+ ) but ineffective (Eff- ) nodules. These Fix+ /Eff- nodules were characterized by significantly lower enzyme activity of glutamine synthetase indicating rhizobial modulation of nitrogen-assimilation by plants. A distant homologue of HemN1 from S. sojae can complement this defect in S. fredii and S. sp. III, but exhibited a more pleotropic role in symbiosis establishment. These findings highlighted the lineage-dependent optimization of symbiotic functions in different rhizobial species associated with the same host.

Aim Most culture-independent studies of bacterial biogeography have been at genus or higher taxonomic levels, although many important processes mediated by bacteria are at the strain or species level, such as the competitive nodulation of rhizobia on legumes. Here, at the intra-species level, we characterized the structural variation in rhizobial populations in soybean rhizosphere under field conditions across 32 sampling sites in three eco-regions. Location North-east (Heilongjiang), north (Hebei–Shandong) and south (Jiangxi) China. Methods The intra-species diversity of rhizobia in soybean rhizospheres was investigated by rpoB pyrosequencing. Soybean nodule isolates were characterized using repetitive extragenic palindromic PCR, restriction fragment length polymorphism of 16S-23S intergenic sequences and rpoB PCR sequencing. Patterns and processes of biogeography of identified rhizobia were studied. Results Significant biogeographical patterns of rhizosphere rhizobia at the species level were found, and the abundant species in the rhizosphere were generally the dominant microsymbionts in soybean nodules. The distribution of rhizobial species in the rhizosphere across eco-regions correlated with combined effects of spatial, vegetative, edaphic and climatic variables. Gene flow and genetic differentiation analyses revealed that there was no dispersal limitation among geographical populations of the same rhizobial species, and drift or subsequent diversification might be involved in shaping the biogeographical pattern in addition to environmental factors. Main conclusions These results constitute the first report of the existence of rhizobial biogeography in legume rhizospheres at the species level, contrasting with most studies, which focused on nodule isolates. The method developed in this study could be used to uncover, at high resolution, the diversity of local rhizobial populations in soils. This information is crucial for choosing suitable strains or species as inoculants for a specific legume host under local field conditions. Moreover, a similar strategy could be used to study other bacteria with important ecological functions.

We present an in-depth study of the failure phenomenon of solid expandable tubular (SET) due to large expansion ratio in open holes of deep and ultra-deep wells. By examining the post-expansion SET, lots of microcracks are found on the inner surface of SET. Their morphology and parameters such as length and depth are investigated by use of metallographic microscope and scanning electron microscope (SEM). In addition, the Voronoi cell technique is adopted to characterize the multi-phase material microstructure of the SET. By using the anisotropic elastoplastic material constitutive model and macro/microscopic multi-dimensional cross-scale coupled boundary conditions, a sophisticated and multi-scale finite element model (FEM) of the SET is built successfully to simulate the material microstructure damage for different expansion ratios. The microcrack initiation and growth is simulated, and the structural integrity of the SET is discussed. It is concluded that this multi-scale finite element modeling method could effectively predict the elastoplastic deformation and the microscopic damage initiation and evolution of the SET. It is of great significance as a theoretical analysis tool to optimize the selection of appropriate tubular materials and it could be also used to substantially reduce costly failures of expandable tubulars in the field. This numerical analysis is not only beneficial for understanding the damage process of tubular materials but also effectively guides the engineering application of the SET technology.

Receiving nodulation and nitrogen fixation genes does not guarantee rhizobia an effective symbiosis with legumes. Here, variations in gene content were determined for three Sinorhizobium species showing contrasting symbiotic efficiency on soybeans. A nitrate-reduction gene cluster absent in S. sojae was found to be essential for symbiotic adaptations of S. fredii and S. sp. III. In S. fredii, the deletion mutation of the nap (nitrate reductase), instead of nir (nitrite reductase) and nor (nitric oxide reductase), led to defects in nitrogen-fixation (Fix

It is the main decrease press type used in high speed train of semi suspension system, as the parameter can not be regulated freely of the semi suspension system, to design a kind of damping shock absorber which with the sensitive and soft system are very important, this system which using of the Electro hydraulic proportional valve to regulation the safety valve, the guide valve and the damping force of shock absorber, get the recycle method of the hydraulic system from inner to outside, and also using the suspension active control variable damping shock absorber to detect the road, this device, in fact, by vibration, which let the valve move relation, turn the mechanical energy into hot and release outside, thus decrease the vibration. To design this variable damping shock absorber ,compared with the semi suspension system ,for it has the connect system and Electro hydraulic proportional valve, and with the road detectors, and various variable parameters, Which let the high speed train more stable and safety, overcome the short of parameter regulation for the semi-automatic suspension system.

In order to investigate the genetic differentiation of Sinorhizobium strains nodulating Glycine max and related microevolutionary mechanisms, three housekeeping genes ( SMc00019 , truA , and thrA ) and 16 symbiosis-related genes on the chromosome (7 genes), pSymA (6 genes), and pSymB (3 genes) were analyzed. Five distinct species were identified among the test strains by calculating the average nucleotide identity (ANI) of SMc00019-truA-thrA : Sinorhizobium fredii , Sinorhizobium sojae , Sinorhizobium sp. I, Sinorhizobium sp. II, and Sinorhizobium sp. III. These species assignments were also supported by population genetics and phylogenetic analyses of housekeeping genes and symbiosis-related genes on the chromosome and pSymB. Different levels of genetic differentiation were observed among these species or different replicons. S. sojae was the most divergent from the other test species and was characterized by its low intraspecies diversity and limited geographic distribution. Intergenic recombination dominated the evolution of 19 genes from different replicons. Intraspecies recombination happened frequently in housekeeping genes and symbiosis-related genes on the chromosome and pSymB, whereas pSymA genes showed a clear pattern of lateral-transfer events between different species. Moreover, pSymA genes were characterized by a lower level of polymorphism and recombination than those on the chromosome and pSymB. Taken together, genes from different replicons of rhizobia might be involved in the establishment of symbiosis with legumes, but these symbiosis-related genes might have evolved differently according to their corresponding replicons.

t is important for dynamic characteristics of electromagnetic release with oil dashpot to calculate the oil damping force. The formula of the oil damping force is deduced by the theoretical formula of viscous damper or according to the experimental results. Therefore, a way to analyze oil damping force of electromagnetic release with oil dashpot is proposed based on Fluent due to the limitations of the two methods in this paper. The curve which is the speed of the plunger variations of the oil damping force is drawn through the numerical analysis of the flow field and the index of the speed is fitted.

In the analysis for overload characteristics of electromagnetic release with oil dashpot, it was difficult to calculate the dynamic behavior of the oil dashpot having long strokes and moving slowly. A method using finite element analysis to obtain the dynamic characteristics of the plunger in the oil dashpot has been developed. Based on the result of the static characteristics, the dynamic characteristics of oil dashpot release are simulated by using ADAMS. Then the relation between the oil damping coefficient and the plunger’s stroke has been discussed. As a result, it is facile to realize the regulation of tripping time for the release through changing the viscosity of silicon fluid.

To achieve effective symbiosis with legume, rhizobia should fine-tune their background regulation network in addition to activating key genes involved in nodulation (nod) and nitrogen fixation (nif). Here, we report that an ancestral zinc finger regulator, MucR1, other than its paralog, MucR2, carrying a frameshift mutation, is essential for supporting nitrogen fixation of Sinorhizobium fredii CCBAU45436 within soybean nodules. In contrast to the chromosomal mucR1, mucR2 is located on symbiosis plasmid, indicating its horizontal transfer potential. A MucR2 homolog lacking the frameshift mutation, such as the one from S. fredii NGR234, can complement phenotypic defects of the mucR1 mutant of CCBAU45436. RNA-seq analysis revealed that the MucR1 regulon of CCBAU45436 within nodules exhibits significant difference compared with that of free-living cells. MucR1 is required for active expression of transporters for phosphate, zinc, and elements essential for nitrogenase activity (iron, molybdenum, and sulfur) in nodules but is dispensable for transcription of key genes (nif/fix) involved in nitrogen fixation. Further reverse genetics suggests that S. fredii uses high-affinity transporters to meet the demand for zinc and phosphate within nodules. These findings, together with the horizontal transfer potential of the mucR homolog, imply an intriguing evolutionary role of this ancestral regulator in supporting nitrogen fixation.

This paper describes a detection system design method of hydrogen engine based on LabVIEW. In order to understand the characteristics and working status of hydrogen fuel engine, we have developed a set of hydrogen fuel engine test system. In the system, LabVIEW is used as the software and DAQ PCI-1802H is the hardware, which mainly realizes the collection, testing, comparison analysis of engine signals and its feature parameters. It has strong functions of signal analysis and processing as well as nice user interface.

Based on the background of the continuous development and application extensive of the remote monitoring and diagnosis, we develop a remote fault diagnosis platform,which can be used as remote fault diagnosis service window. The client and the server can be used for data analysis and processing, also on data management to achieve remote monitoring and diagnosis. Meanwhile we design a remote data analysis system in LabVIEW environment to realize the signal analysis and transmission. In order to strengthen the system network measurement function, this paper introduces DataSocket and TCP/IP technology in the remote transmission, which is a new technique in improving the ability of the remote data transmission.

Multi-dimensional nonlinear knapsack problem is a bounded nonlinear integer programming problem that maximizes a separable nondecreasing function subject to multiple separable nondecreasing constraints. This problem is often encountered in resource allocation, industrial planning and computer network. In this paper, a new convergent Lagrangian dual method was proposed for solving this problem. Cutting plane method was used to solve the dual problem and to compute the Lagrangian bounds of the primal problem. In order to eliminate the duality gap and thus to guarantee the convergence of the algorithm, domain cut technique was employed to remove certain integer boxes and partition the revised domain to a union of integer boxes. Extensive computational results show that the proposed method is efficient for solving large-scale multi-dimensional nonlinear knapsack problems. Our numerical results also indicate that the cutting plane method significantly outperforms the subgradient method as a dual search procedure.

The genus Bradyrhizobium has been considered to be a taxonomically difficult group. In this study, phylogenetics and evolutionary genetics analyses were used to investigate divergence levels among Bradyrhizobium strains nodulating soybeans in China. Eleven genospecies were identified by sequence analysis of three phylogenetic and taxonomic markers ( SMc00019 , thrA , and truA ). This was also supported by analyses of eight genes outside the symbiosis island (“off-island” genes; SMc00019 , thrA , truA , fabB , glyA , phyR , exoN , and hsfA ). However, seven genes inside the symbiosis island (“island” genes; nifA , nifH , nodC , nodV , fixA , trpD , and rhcC2 ) showed contrasting lower levels of nucleotide diversity and recombination rates than did off-island genes. Island genes had significantly incongruent gene phylogenies compared to the species tree. Four phylogenetic clusters were observed in island genes, and the epidemic cluster IV (harbored by Bradyrhizobium japonicum , Bradyrhizobium diazoefficiens , Bradyrhizobium huanghuaihaiense , Bradyrhizobium liaoningense , Bradyrhizobium daqingense , Bradyrhizobium sp. I, Bradyrhizobium sp. III, and Bradyrhizobium sp. IV) was not found in Bradyrhizobium yuanmingense , Bradyrhizobium sp. II, or Bradyrhizobium elkanii . The gene flow level of island genes among genospecies is discussed in the context of the divergence level of off-island genes.