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Herbivores harbor gut microbes that affect their development and contribute to their nutrition, reproduction, and survival. Plant defenses could target the herbivore’s beneficial gut microbes, but this has not been well studied in rice. In this context, we identified a rice terpene synthase gene, Os04g0341500. It was strongly induced after feeding by rice striped stem borers (SSB, Chilo suppressalis), and it can catalyze the (E)-β-farnesene (Eβf) synthesis. When added to artificial diets, Eβf impaired the development and survival of SSB larvae. High-throughput amplicon sequencing revealed that SSB fed on Eβf were decreased in beneficial gut microbes, compared to those feeding on the corresponding control feed. In vitro feeding of Eβf suggested that this antimicrobial sesquiterpene directly inhibited the growth of SSB gut microbes. The present study suggested that the Eβf-induced decrease of relative abundance of gut microbes potentially impairs larval development and survival in SSB.

The development of semiconductor technology has enabled the planarization and miniaturization of microwave sensors and it brought challenge for near-field microwave measurements at micro and nanoscale. In this article, we propose a method for detecting microwave frequency on sensing chip surface with high resolution via scanning probe microscopy and microwave detection technology. The radiated signal of microwave sensor is determined by analyzing the center frequency of the ${S}_{{11}}$ oscillation curve, and the high-precision measurement of both single-frequency and multifrequency signals is achieved over a wide operating range of frequencies (100 kHz–10 GHz), with low power (−20 dBm) and minimal error (8 Hz). Due to the simplicity, flexibility, and accuracy of frequency identification technique, the proposed method can be applied to the design, failure analysis, and performance optimization of microwave sensor at micro and nanoscale.

This study primarily offers a theoretical analysis and experimental validation of microwave power detection based on the variations in the probe signal of the scanning microwave microscopy and the microwave signal from the surface of electronic devices. On the one hand, maintaining constant input power for the sample and the probe, we analyze the shift in the peak-to-peak value of the $S_{{11}}$ curve with power differences at surface positions. On the other hand, maintaining a constant test position and varying input power of the probe, the peak-to-peak measurement sensitivity varies nonlinearly with the surface microwave power. Based on the relevant theoretical and experimental results, it has been determined that modifying the input power of the probe has the potential to enhance the sensitivity of microwave power measurement and extend the range of power measurement. This article establishes the upper and lower power detection thresholds at 12 and −60 dBm, respectively. These results offer valuable insights for effectively detecting surface power levels of microwave electronic devices with wide-ranging capabilities and high sensitivity.

With the development of microwave chips toward high integration, new challenges have been posed to high-precision microwave field test techniques. In this article, we propose a chip surface microwave field characterization method and design a corresponding microwave power measurement system based on a scanning probe imaging system and microwave test technology. The minimum detected microwave power of the system is better than 1 nW by experimental verification. The proposed method can be applied to image the distribution of the microwave field of the chip and it is helpful to optimize chip design and performance in the future.

ABSTRACTGeographical flows depict the movement of geographical objects from origin to destination. They can be applied to represent activities such as commuting, commodity trade, information exchange, and migration. The topological relationship model of geographical flows can provide information on the interactions between objects by describing whether two flows are disjoint or coincide partially or completely. For example, it can be applied to determine whether car trips within a city can be shared, identify takeout orders that can be delivered together, and prevent drone collisions. The ability to describe the topological relationship and relative direction between flows is important for analyzing the interaction between two objects. However, although many topological relationship models exist for lines, they are unable to describe both the topological relationship and the relative direction between lines accurately. To address this issue, this study developed a topological relationship model for geographical flows through the formalism of the 9-intersection model that can describe both the topological relationship and the relative direction between two flows. By removing non-existent relationships based on certain constraints, fifteen topological relationships are obtained and classified into six topological predicates. A method for determining the topological relationships was also developed that compares the section IDs and offsets of flows. The developed topological relationship model for flows was evaluated by examining a carpooling scheme based on taxi origin–destination flow data. The results show that the topological relationship model can describe the interactions among objects and select the flows that have specific interactions with other flows.

The advent of the information era has resulted in exceptional advances in geographic science. The domain of geographic science has expanded from traditional physical and human geography to physical, human, and information geography, resulting in the emergence of the field of information geography. Three subdisciplines have gradually formed, i.e., geographic remote sensing science, geographic information science, and geographic data science. With a view towards preparing a description of the disciplinary structure of geographic science for the “Development Strategy of Discipline and Frontier Research in China (2021–2035)”, this article summarizes the history, definition, and disciplinary structure of information geography. The strategic layout of the discipline, along with the goals and key directions of priority development fields, are also highlighted. The insights into this new discipline provided in this paper will promote the development and application of remote sensing and geographic information within the framework of geographic science, advancing the synthesis of geographic research and the integrated development of geographic science.

Compelling evidence supports a causal role for lipoprotein(a) (Lp(a)) in cardiovascular disease. No pharmacotherapies directly targeting Lp(a) are currently available for clinical use. Here we report the discovery and development of olpasiran, a first-in-class, synthetic, double-stranded, N-acetylgalactosamine-conjugated small interfering RNA (siRNA) designed to directly inhibit LPAmessenger RNA translation in hepatocytes and potently reduce plasma Lp(a) concentration. Olpasiran reduced Lp(a) concentrations in transgenic mice and cynomolgus monkeys in a dose-responsive manner, achieving up to over 80% reduction from baseline for 5–8 weeks after administration of a single dose. In a phase 1 dose-escalation trial of olpasiran (ClinicalTrials.gov: NCT03626662), the primary outcome was safety and tolerability, and the secondary outcomes were the change in Lp(a) concentrations and olpasiran pharmacokinetic parameters. Participants tolerated single doses of olpasiran well and experienced a 71–97% reduction in Lp(a) concentration with effects persisting for several months after administration of doses of 9 mg or higher. Serum concentrations of olpasiran increased approximately dose proportionally. Collectively, these results validate the approach of using hepatocyte-targeted siRNA to potently lower Lp(a) in individuals with elevated plasma Lp(a) concentration.

Metacognitive intervention of listening has prevailed in L2 (Second Language) listening research in the past decade. However, rare research has linked metacognitive intervention with online listening. This study examines L2 learners’ development of metacognitive awareness of listening through online metacognitive listening practice. A set of online metacognitive listening exercises were constructed, based on a metacognitive cycle that regularly guides learners through metacognitive processes of listening. Thirty-nine low-proficiency Chinese university EFL listeners from one intact class participated in the study and did online listening practice as individual outside-class homework for 14 weeks. The development of metacognitive awareness was measured by MALQ and enriched by the learners' reflective notes. Results reveal an inverted U-shape pattern in the development of metacognitive awareness and that the factors of metacognitive awareness develop asynchronously. Some factors appear more susceptible to listening task difficulty and more unstable in the development process.

•Clarify the definitions and frameworks of GIScience and remote sensing (RS)•Discuss the roles of GIScience and RS in natural resource and environmental science•Forecast future directions for remote sensing and GIScience

Customer profiles that include gender and age information are important to businesses and can be used to promote sales and provide personalized services. This information is gathered in e-commerce by analyzing customer visit records in virtual web space. However, such practice is difficult in brick-and-mortar businesses because the data that can be utilized to infer customer profiles are limited in physical spaces. In this paper, we attempt to infer the gender and age of customers using indoor positioning data generated by the Wi-Fi engine. To achieve this, we first construct a synthesized features vector to distinguish different profiles. This vector contains both customer spatial–temporal mobility characteristics and interest preferences. A hidden Markov model group detection method is then applied to detect customers who shop together because they usually show the same shopping behavior and it is difficult to distinguish their profiles. Finally, a random forest inference model is proposed to infer profiles of customers who shop alone. The indoor positioning data collected in the Longhu Tianjie Plaza in Chongqing were used as a case study. The result shows that customer profiles are indeed inferable from indoor positioning data. The accuracy of the gender inference model reaches 73.9%, while that of the age inference model is 67.9%. This demonstrates the potential value of new “big data” for promoting precision marketing and customer management in brick-and-mortar businesses.

•GIS with big data provides geospatial information to fight COVID-19.•Big data showed power on epidemic transmission analysis and prevention decision making support.•Challenges still continue in data aggregation, knowledge discovery, and dynamic expression.

The objective, connotations and research issues of big geodata mining were discussed to address its significance to geographical research in this paper. Big geodata may be categorized into two domains: big earth observation data and big human behavior data. A description of big geodata includes, in addition to the “5Vs” (volume, velocity, value, variety and veracity), a further five features, that is, granularity, scope, density, skewness and precision. Based on this approach, the essence of mining big geodata includes four aspects. First, flow space, where flow replaces points in traditional space, will become the new presentation form for big human behavior data. Second, the objectives for mining big geodata are the spatial patterns and the spatial relationships. Third, the spatiotemporal distributions of big geodata can be viewed as overlays of multiple geographic patterns and the characteristics of the data, namely heterogeneity and homogeneity, may change with scale. Fourth, data mining can be seen as a tool for discovery of geographic patterns and the patterns revealed may be attributed to human-land relationships. The big geodata mining methods may be categorized into two types in view of the mining objective, i.e., classification mining and relationship mining. Future research will be faced by a number of issues, including the aggregation and connection of big geodata, the effective evaluation of the mining results and the challenge for mining to reveal “non-trivial” knowledge.

Proxy re-encryption cryptosystem enables proxy to re-encrypt the ciphertext and protects the privacy of the corresponding plaintext. Hence, this type of cryptosystem has found tremendous applications in data sharing in cloud computing, email forwarding, securing file systems, and so on. In practice, proxy re-encryption has to support verification of ciphertext to reduce the users’ computational burden. The ciphertext verification can be achieved through a public, private, or delegatable manner. Delegatable verification is more generic in that it can be easily converted into the other two verification methods. However, almost all existing schemes with delegatable verifiability only achieve replayable chosen ciphertext security. Hence, in this paper we propose a more secure proxy re-encryption scheme with delegatable verifiability. Specifically, we utilize a short signature scheme to prevent an attacker from forging a valid ciphertext, and prevent an attacker from forging a signature. As a result, our scheme is secure against chosen ciphertext attacks under the standard model.

A microwave probe plays a critical role in near-field imaging, and there is a continuous effort to develop them through straightforward methods. This study designed and fabricated an oscillating metal probe and used it for scanning microwave imaging of micro-nano structures. The surface smoothness of the cantilever is approximately 19.3 nm after polishing with diamond abrasive paper, and the tip radius is less than 20 nm using electrochemical etching. The impact of metal electrode materials on microwave signals was assessed in the frequency range of 1–20 GHz. The microwave imaging capability of the devised probe was explored through the imaging of a micro-nano structure. The spatial resolution of microwave imaging reached 0.5 μm over a scanning area of 50 μm × 50 μm. This study has far-reaching significance for developing higher-performance microwave probes and advancing scanning microwave microscopy.

Traumatic brain injury leads to problems with movement and cognitive deficits and has a high mortality rate. Cornel iridoid glycoside, the active ingredient of Cornus officinalis, has been reported to ameliorate apoptosis and inflammation in rats. We investigated the therapeutic effect of cornel iridoid glycoside on neuroinflammation in rats with brain injury. Rats were treated with cornel iridoid glycoside, and then measurements of antioxidant, proinflammatory marker, and NF-κB and STAT3 mRNA and protein levels, as well as a histopathologic analysis, were conducted. Cornel iridoid glycoside significantly reduced lipid peroxidation and TNF-α and IL-6 levels but increased the levels of antioxidants. In addition, cornel iridoid glycoside significantly decreased the expression of NF-κB and STAT3. Histopathological analyses showed that cornel iridoid glycoside reduced the severity of neuroinflammation and apoptosis. Therefore, cornel iridoid glycoside significantly ameliorated neuroinflammation by reducing lipid peroxidation and proinflammatory marker levels and increasing antioxidant levels in rats with brain injury.

Core IdeasExplored the impact of variables selected by different means on mapping at a watershed scale area.Identified influential topographic variables with appropriate scales for mapping soil properties.Finding the appropriate scales of local attributes is helpful for mapping soil properties accurately.Local attribute scale helped map accuracy vs. use of local and regional attributes at single scale. The influential environmental variables and their appropriate scales for mapping different soil properties are usually different. Comparisons between variables selected using machine learning and knowledge‐based approaches and their impacts for soil mapping are necessary to provide guidelines on selecting environmental variables. This study compared topographic variables with single and multiple scales selected for five soil properties (topsoil clay content, sand content, silt content, topsoil organic matter content (SOM), and soil depth) using a recursive feature elimination (RFE) algorithm and variables selected based on expert knowledge on mapping. One hundred and seventy‐three variables were generated including five single‐scale variables derived with a 3 × 3 neighborhood size and seven multi‐scale variables with various neighborhood sizes. Subsets 1 and 2 were selected from single‐scale variables (Pool 1) and all variables (Pool 2), respectively. A reference Subset 3 was selected based on soil pedogenesis knowledge. Results showed that variables in Subset 1 included both local and regional terrain attributes, but were considerably different to the reference variables. When considering scales, local variables at specific scales became the most important variables. Mapping accuracies using Subset 2 were the highest for all soil properties. This indicates that finding the appropriate scales of local attributes and using common local attributes with appropriate scales is more helpful than using both local and regional attributes at single scale for mapping soil properties accurately. The RFE approach is efficient for selection of variables. Also, the input environmental variables for selection determine whether the selected variables perform better than all input variables without selection for predicting soil properties.

Cities based on coal resources have increasingly important social and economic roles in China. Their strategies for sustainable development, however, urgently need to be improved, which represents a huge challenge. Most observers believe that the continued progress of these cities relies on the optimization of scientific adaptive management in which social, economic, and ecological factors are incorporated. A systems perspective that combines policies, management priorities, and long-term policy impacts needs to be applied. To date, however, such an approach has not been adopted, which means it is difficult to implement adaptive management at the regional scale. In this study, we used various situations to develop a multiple adaptive scenario system dynamics model. We then simulated a range of policy scenarios, with Ordos in the Inner Mongolia Autonomous Region as a case study. Simulation results showed that the current strategy is not sustainable and predicted that the system would exceed the environmental capacity, with risks of resource exhaustion and urban decline in 2025–2035. Five critical policy variables, including the urban population carrying capacity, rates of water consumption and water recycling, and expansion of urban land cover, were identified during sensitivity analysis. We developed and compared six socio-economic scenarios. The urban area, represented by the urban population density, seemed to transition through five different stages, namely natural growth, rapid growth, stable oscillation, fading, and rebalancing. Our scenarios suggested that different policies had different roles through each stage. The water use efficiency management policy had a comprehensive far-reaching influence on the system behavior; land urbanization management functions dominated at the start, and population capacity management was a major control in the mid-term. Our results showed that the water recycling policy and the urban population carrying capacity were extremely important, and both should be reinforced and evaluated by the local governments.

Using lignocellulose to produce nitrogen-rich bio-oil and nitrogen-doped biochar in the presence of nitrogen-carrying bodies has become a research hotspot in recent years for high-value conversion and utilization of biomass. Different nitrogen carriers significantly influence biomass pyrolysis and conversion process and products. In this study, a new strategy for the preparation of both nitrogen-rich bio-oil (high-value N-containing compounds (NCCs)) and N-doped biochar by ammonia impregnation treatment coupled with Zeolite Socony Mobil Five (HZSM-5) via N-enriched pyrolysis was proposed. The influence of amine type (formamide, urea, melamine and dicyandiamide) and concentration on the product content, distribution, properties and evolution mechanism was also explored. The results showed that the amine treatment significantly reduced the activation energy (from 23.71 kJ/mol to 12.35–20.82 kJ/mol) and N content (from 7.42% to 6.05–7.29%) due to destruction of the crystalline phase and amine volatilization but increased the amount of char formed (from 18.15% to 21.47–24.06%). The amino groups derived from four different ammonia sources (formamide, urea, melamine and dicyandiamide) reacted with biomass-derived O-containing compounds to form pyridinic- and graphitic-like biochar due to NH3etching and activation, and the enhanced adsorption capacities decreased in the order melamine (107.95 m2/g) > urea (96.84 m2/g) > dicyandiamide (79.46 m2/g) > formamide (74.12m2/g) > biochar (35.63 m2/g)) due to the higher specific surface areas, pore volumes, graphitization degrees and enrichment of the O/N-containing functional groups. Additionally, higher concentrations of formamide coupled with the HZSM-5 catalyst noticeably boosted the NCCs content and pyrrole selectivity. The maximum NCCs content and pyrrole selectivity were 82.97% and 52.45%, respectively, and these were obtained via catalytic pyrolysis with HZSM-5 when the formamide concentration was 15%. Furthermore, formamide preferentially generated NCCSs and pyrroles via the Maillard reaction, and urea facilitated amine formation. This research provides useful background knowledge and a novel process for transformation and recovering high value-added NCCs products by N-rich pyrolysis of ammonia impregnated biomass.

The constant strain rate uniaxial compression tests were conducted in this paper for studying the work hardening behavior and revealing the underlying microstructure evolution involved in the plastic response of the nickel-based Inconel X-750 alloy. The work hardening rate versus true strain plots of Inconel X-750 alloy resembled that of low-stacking-fault energy (SFE) alloys with distinct four stages. The dislocations were found in the planar arrangements at a strain of 0.1 located at the onset of stage II, and the dislocation density was increased and the planar arrangement configuration was partially destroyed at a strain of 0.36 located in stage III. It was unexpected that deformation twins were observed at a strain of 0.69 located in stage IV although the alloy has been classified into materials with a higher SFE value. The result is different with a similar study, in which the deformation twins were absent in Ni–Cr-based alloy Inconel 625 even when the strain was as high as 0.65. It was deemed that the low level of solution strengthening favored the deformation of matrix and the activation of slip system for twining in Inconel X-750 alloy. Unlike the low-SFE alloys that the twins were always formed at the end of stage I, the higher SFE delayed the twin formation to stage IV for Inconel X-750 alloy. The well-developed planar dislocation configuration gave rise to the stage II with a slightly decreasing rate, the collapse of planar dislocation arrangements caused the occurrence of stage III with an accelerated decreasing rate, and the twin formation led to the stage IV with a nearly constant work hardening rate.

Conductor–insulator composites have been extensive researched for high dielectric constant. Most of them concentrated on metal polymers or metal ceramics. Barium titanate–carbon fibers composites were prepared by using a solid state reaction process with carbon fibers contents ranging from7 vol% to 23 vol%. Due to the high-aspect-ratio of carbon fiber, it was easy to produce a conducting network at much lower volume fraction. FESEM images illustrated that the carbon fibers influenced the densification and microstructure of the ceramics. Besides, addition of carbon fibers led to increase in dielectric permittivity, also had effects on the dielectric loss and ac conductivity. The dielectric and conductivity properties as a function of carbon fibers volume fraction were explained by the percolation theory.

The multi-walled carbon nanotube/alumina (MWCNTs/Al2O3) nanocomposites embedded with the shortened MWCNTs were prepared by pressureless sintering. The microstructure, conductive behavior and complex permittivity spectra of the composites were investigated. It was found that MWCNTs, which were shortened to low aspect ratio by the controllable acid and ultrasonic treatment, uniformly dispersed in the Al2O3 matrix. A unique dielectric resonance-induced negative permittivity behavior was observed in the composites with high MWCNTs content. The negative magnitude of permittivity was small (~-50) in the testing frequency. The dielectric loss peaks being accompanied by dielectric resonance moved to the higher frequency with increasing MWCNTs content. Those composites underwent a capacitive-inductive transition with increasing frequency and their conductive mechanism was hopping conduction. This work is beneficial to explore the generation mechanism of negative permittivity, and will greatly facilitate the practical application of metamaterials.

Due to the distinct electromagnetic properties, double negative materials have bright application prospect in many areas in the future. The nickel (Ni)/polyphenylene sulfide (PPS) composites were prepared by hot pressing Ni and PPS powders mixture. Microstructures, dielectric properties, and magnetic performances of the resulted composites were studied in detail. Once Ni contents exceeded the percolation threshold, the conductive networks would form and the conduction mechanism would change from hopping conduction to metal-like conduction. Due to the plasma oscillation of the free electrons within the conductive networks, negative permittivity appeared. Interestingly, circuit loops in the connected Ni particles induced by external electric field resulted in a diamagnetic phenomenon under high frequency for the composite with ferromagnetic Ni particles.

Al/Epoxy composites with different Al content were prepared by insulation coating process including high energy ball milling and hot press. The electrical properties and magnetic performance including ac conductivity, permittivity, reactance and permeability were investigated in detail. The frequency dispersions of ac conductivity followed the power law, indicating the hopping conduction behavior. The real part of permittivity for composites increased with higher Al content, which was attributed to the more interface between Al and epoxy. Besides, the real part of the relative permeability decreased with higher Al content in high frequency.

The dual metallic components, i.e., iron-aluminum particles were distributed in alumina matrix to fabricate lossy cermets. The electromagnetic parameters including ac conductivity, the complex permittivity and permeability were investigated. With the increase of filler fractions, the conductive carriers instead of the dipoles played a primary role in conductive and dielectric properties. Hopefully, the cermets composites could be promising candidates for electromagnetic wave attenuation and shielding.

In this paper, Fe/SiO2 composites with different Fe content were prepared through pressureless sinter in weakly reductive atmosphere after high energy ball milling. The electrical properties including ac conductivity, permittivity were investigated in detail. The results showed that the frequency dispersions of ac conductivity follow the power law, indicating the hoping conduction behavior. The real part of permittivity for composites increased with higher Fe content, which was attributed to the more interface between Fe and SiO2. Besides, Debye-like dielectric relaxations were observed, and the Debye-like loss peak appeared blue shift as increasing the Fe content.

We have designed a gripper for scanning microwave microscopy (SMM) based on atomic force microscopy, which is optimized for impedance-matching structures and high-frequency microwave loss. The gripper is simple in construction and highly integrated. The return loss near the target operating frequency of 20 GHz is less than −30 dB. The minimum detected power reach −40 dBm with the order of nW. The microwave scanning image of the sample surface structure was experimentally tested, showing that the gripper can be applied to microwave scanning imaging. The research results have contributed to the development of SMM.

In this paper, C/SiO2 bulk composite was prepared via SiO2 microspheres’ self-assembly process combined with heat treatment. SEM and impedance analyzer was used to investigate the microstructure and high-frequency dielectric properties of the composites. The results show that SiO2 microspheres constituted the composite matrix, whose porosity was slightly higher than the densest hexagonal stacking. Sheet carbon distributed in pores formed by SiO2 microspheres. The real and imaginary parts of the dielectric constant of the composite material increased with the content of carbon, but decreased with the frequency. The permittivity of C/SiO2 composite could be adjusted by control the concentration of PVA solution.

FeSiCr-epoxy composites consisting of different FeSiCr contents were prepared through the pressure molding after mixing by cryomilling at liquid nitrogen temperature. The electromagnetic properties including ac conductivity, permittivity, and permeability were investigated in detail. The results show that the frequency dispersions of ac conductivity followed the power law, indicating the hoping conduction behavior. The real permittivity of composites increased with the increase of FeSiCr contents, and the enhancement of permittivity may be attributed to the increase of the interface area between FeSiCr and epoxy, while Debye-like dielectric relaxations were observed, and the fitting analysis of Cole-Cole curve indicates a nonideal Debye relaxation. The frequency dispersions of permeability were also relaxation linetype, which is attributed to the domain wall displacement.

SiC films made of different methods may have different mechanical properties, so their mechanical properties need to be determined by mechanical property measurement [1]. Since SiC films have stable chemical properties, it’s very difficult to be etched [2]. This paper introduce a method for SiC films mechanical property testing without processing SiC. Moreover, in view of the lack of square SiC films’ mechanical properties research, this paper also do simulation on it.

The key for gel-casting is the preparation of ceramic aqueous slurries with excellent rheological properties. The effect of ammonium polyacrylate and pre-oxidation on rheological properties of Si3N4 slurries was investigated. The Si3N4 isoelectric point (IEP) is between 3 and 4 in premix solution and particle surface potential is maximum at pH between 9.5 and 10.5. PAA-NH4 of dispersant can obviously decrease the viscosity of Si3N4 slurries, and the optimal dosage is about 1.6wt% of Si3N4 powders. Meanwhile, the Si3N4 slurries exhibit pseudoplastic fluid with the characteristic of shear-thinning behavior. Due to the improvement of powder surface characteristic, the pre-oxidation significantly improve the rheological properties of the Si3N4 slurries.

The microstructure and dielectric properties of the graphene–epoxy composites prepared by cryomilling at liquid nitrogen temperature were studied by SEM and RF impedance material analyzer. The result indicated that both the dielectric constant and conductivity of the composites increased with the increase of the graphene content. The value of the dielectric constant of the composite with about 8 wt % of graphene was as high as 200. Moreover, the frequency dispersion behaviors of the conductivity within a certain frequency range accorded with the Jonscher's power law demonstrating that the conductive mechanism is hopping conduction. The negative reactance decreased with the increase of the testing frequency which indicated a capacitive character

The precursor nickel and manganese carbonates were synthesized by co-precipitation with sodium carbonate as precipitant, and then nickel and manganese oxides were gained after calcination. The phase and morphology of the synthesized product were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM), and the electrochemical characterization was performed using cyclic voltammetry (CV), galvanostatic charge–discharge tests (GCD) and electrochemical impedance spectroscopy (EIS) in a 6mol/L KOH aqueous solution electrolyte. The result showed that the products were the mixture of nickel and manganese oxides and solid solution. nanoparticles and spherical particles were gained by controlling the molar ratio of nickel and manganese. All of the samples exhibited typical Faradic redox capacitance. The specific capacitance was different with the change of nickel and manganese molar ratio. The specific capacitance (Cs) reached 130F/g at 1A/g when the ratio was 2:1.

The precursor Ni (OH)2 was synthesized by a simple hydrothermal method with hexamethylenetetramine ((CH2)6N4) as precipitant and template, and then NiO was gained after calcination. The phase and morphology of the synthesized product were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM), and the electrochemical capacitive characterization was performed using cyclic voltammetry (CV), chronopotentiometry and electrochemical impedance spectroscopy (EIS) in a 6mol/L KOH aqueous solution electrolyte. The result shows that spherical NiO without impurity was synthesized, the average diameter of the spheres is 5 um and these spheres were constructed by the interactive arrangement of many nanoflakes in three dimensions. This kind of NiO shows the typical electrochemical characteristics of pseudo capacitance with high specific capacity and excellent rate capability. The specific capacity can reach 515F/g at the current density of 1A/g

Thermocatalytic co-pyrolysis of agro-forestry residue and LDPE waste was used to improve aromatic-rich bio-oil with combining CeZrAl and HZSM-5 dual catalyst. The influence of pyrolysis parameters on pyrolysis characteristics, kinetics, aromatic yield and selectivity was investigated; the synergistic effect and additive effect for promoting aromatic hydrocarbons with and without catalysts were determined based on the experimental and theoretical hydrocarbon content; and the reaction mechanism was also described by analyzing the free radicals. Experimental results showed that LDPE with a higher H/Ceff ratio promoted biomass pyrolysis to produce aromatic-rich bio-oil with mass transfer and radical explanation. Dual catalytic co-pyrolysis remarkably increased hydrocarbon and aromatic hydrocarbon (AHs) contents. When the proportion of HZSM-5 was greater than 50%, the layered mode was more conducive to the formation of aromatics and more conducive to the conversion of alkyl benzene, while the mixed mode was more conducive to the conversion of olefins with a higher CeZrAl ratio, which facilitated the formation of toluene, xylene, BTXE and MAHs. The optimum aromatic, BTXE and MAH yields and selectivity (88.49%, 59.48% and 68.00%) were observed at 500/550 °C for a 1:2 CeZrAl to HZSM-5 ratio and a biomass to LDPE ratio. Abundant free radicals were produced and improved the mechanism’s synergistic effect.

Based upon the synopsis of electronic information system and system integrated support, this paper puts forward integrated support model of electronic information system, and sets forth a series of policies and measures, such as strengthening technical practices of general quality characteristics, advancing system integration of integrated support information, and studying and applying software support technology. This will benefit the further development of electronic information system and integrated support engineering.

The precipitating behavior of δ phase in GH4169G alloy at 910°C was investigated and a novel process for achieving fine-grained GH4169G sheet with average grain size of ASTM13 was proposed. Globular δ phase precipitation precedes that of the plate-like δ phase, forming at grain boundary first and later in grain. After globular δ phase reaches a peak volume, it begins to transform into plate-like in grain boundary, and then the plate-like δ phase forms in grain in certain direction. The grain-fined process includes the following steps:(1) solution treated at a proper temperature, then air cooled; (2) soaked for δ phase precipitation; (3) cold rolled; (4) annealed for recrystallization. Microstructure analysis from optical microscopy (OM) and scanning electron microscopy (SEM) revealed that both plate-like and globular δ phase remarkably restrained the grain growth during annealing recrystallization. The optimum parameters for the grain refinement were determined finally.

In this paper, uniaxial compression testsfor GH4145 superalloywere conducted on Gleeble-3800 at room temperature and 60°C with strain rates ranging from 0.5s-1 to 10s-1. No cracks were observed in all the specimens deformed from 10% to 70%, indicating that the GH4145 superalloy possesses great ductility under room temperature. The flow stress of GH4145 superalloywas not sensitive to strain rate deformed around room temperature and it decreased slightly with the temperature increasing. Dynamic recovery during deformation will start to balance the effect of work hardening when the true strain was arisen up to 0.4. Good agreement between the calculated and simulated temperature and strain shows that calculation method is accurate enough for the prediction.

Remotely sensed measurements of anthropogenic nocturnal lighting have been extensively used for studying human settlements and socioeconomic dynamics. Considerable efforts have been devoted to build the connections between nightlight signals and demographic and economic variables at local to global scales in order to obtain observationally based estimates for human activity. Recently, the first cloud-free composite of global nighttime light data derived from the Suomi National Polar orbiting Partnership (Suomi-NPP) with the Visible Infrared Imaging Radiometer Suite (VIIRS) sensor yields an increasingly clearer view of the earth surface on nights. The responses to socioeconomic activity and the potential utility of VIIRS nighttime light data, however, still remain less well understood. In this study, we examined the quantitative relationships between VIIRS nightlight-derived indices and socioeconomic variables at fine and local scales. Our results suggest that the total night radiance has significant positive associations with two airport performance indicators – passenger traffic and aircraft movement. In addition, there is a strong correlation with four urbanization variables – human population, gross domestic product, electric power consumption and paved road area. Our findings suggest that VIIRS nightlight data could be more indicative of socioeconomic dynamics and may provide insights into the potential applications for studying human settlement and urbanization processes based on anthropogenic nocturnal lighting.

Hydrological exploration tests are designed and field data are acquired. By combination of theories and experiments, hydro geological condition and water filling factors of Mayingbao coal mine field are analyzed systematically aiming to ascertaining threatening degree of water hazard of the mine field and studying theory of mine water hazard prevention and control. According to coupling theory between GIS and AHP, models of “water abundance index” and “vulnerability index” are founded respectively. By methods of “three maps-double predictions” and “vulnerability index”, water inrush probability from roof and floor of chief exploitable coal seams in the mine field are evaluated quantitatively. Comprehensive regionalization of roof water filling probability and evaluation regionalization of floor water inrush vulnerability of the seams are formed. Based on above study, water inflow of first mining area is predicted and suggestion of water prevention and control for safety production is put forward. Nonlinear and multivariate theory in present geoscience research is improved because of the above results and the research provides necessary basic data for the mine designing, preliminary and feasibility research and subsequent safety production.

Freestanding ultralong (900 μm) aligned carbon nanotube (ACNT) films were studied as both an electrode material and a dry adhesive binder with the current collector in lithium ion batteries. Results revealed the formation of a solid electrolyte interface (SEI). The amazingly large initial discharge capacity (1836 mAh g-1) indicated that the ACNT electrode we utilized had great potential for the intercalation of Li ions resulted from extremely large surface area of ACNT films. And electrochemical performances also exhibited excellent cycling stability for this ACNT electrode because of the presence of SEI and the unique structure of the electrode itself.

Silica films prepared by the base catalyzed sol–gel process show poor mechanical property. In this study, silica anti-reflective films with good mechanical property have been prepared by the catalyzed sol–gel process with dimethyl formamide added as drying control chemical additives. The silica sol was first dip deposited onto substrate to form films on both sides of the substrate and then subjected to thermal treatment. After thermal treatment, the film was achieved due to the formation of porous structure in the resultant film as a result of decomposing tetraethylorthosilicate and dimethyl formamide. Nano-indenter measurement shows that the Young’s modulus and hardness of base catalyzed films are 10-20GPa and 0.25-0.55GPa, respectively. But the films added with dimethyl formamide are much better than those films derived from base-catalyzed silica sols, the Young’s modulus and hardness are 32-39GPa and 1.22-1.47GPa, respectively. The good mechanical properties make such films potential in both military and civil applications.

Thermal conditioning (TC) can improve sludge mechanical dewaterability and drying performance, and produce solid fuel from sewage sludge with low-cost and harmlessness. This study investigates the influence of the TC on sludge combustion with thermogravemetric analysis of sewage sludge with/without TC. The experiments were carried out at a 150 mL/min air ambient with a heating rate of 10, 20, 30, 40, 50 °C/min. Tow integration approximation methods (Coats-Redfern and Flynn,-Wall-Ozawa) and a differential method (Kissinger method) were applied to study the kinetics. The Coats-Redfern method requires assuming the reaction’s kinetic mechanism. The calculated activation energy was lower than that from the Flynn-Wall-Ozawa and Kissinger, which were very close to each other. Among these methods, the Flynn-Wall-Ozawa can predict the energy required at every combustion stage, which therefore would be the best one to explore the combustion mechanism. The results show that the organic matters within sewage sludge are much more homogeneous after TC. The combustion of the thermal conditioning sludge (TCS) is much more stable with a 10% reduction in burnout time and a 9.94% reduction in combustion temperature range. The ignition temperature of the raw sludge keeps increasing from 188 to 224 °C with the heating rate, while that of the TCS is almost constant at 222-240 °C. The TC can improve the activation energy, which is about 144.52 and 123.00 kJ/mol for the raw sludge (RS) and TCS. Considering the gaseous pollutant emissions, the TC can dramatically reduce NO emissions, which is decreased from 14.22 to 6.59 mg/g by the TC, representing a reduction of 50.7%. Therefore, the TC can promote the hydrolysis of macromolecular organics, which would improve the sludge combustion performance, and reduce the gaseous pollutant emissions from combustion.

With the STX-50 pneumatic-typed dynamic triaxial system, the undrained dynamic triaxial tests on the saturated cohesive soil are performed to study the dynamic strength properties. The changing process of the dynamic strength, backbone curve and the soil deformation of the cohesive soil under dynamic load are zoom analysis by stages to get their regularity. It is found that the stage change of the dynamic strength, backbone curve and the soil deformation all exist, which the stage I of the soil deformation has little damage, the stage III is not allowed, the stage II is determined by the importance of the concrete and the sensitive degree to the deformation. In order to analysis the deformation stability and stress stability of the formation in the effect of the dynamic load, provide qualitative and quantitative basis for the soil dynamic study.

Plant growth at northern latitudes is highly responsive to the climatic changes that have occurred over recent decades. However, the sensitivity of the phasing of the seasonal cycle of terrestrial ecosystems to a changing environment remains less widely understood. We present an investigation and comparative study of large-scale changes in seasonal cycling of both land surface temperature and plant growth. Our results have shown trends indicating a marked increased towards overall plant productivity by ∼3% from 1982 to 2005, reduced trends in seasonal variation at low-mid latitudes by ∼2%, increased trends in seasonal variations at mid-high latitudes by ∼7%, and an earlier phase in northern terrestrial ecosystems (∼1.1 days) in parallel with changes in the phasing of surface temperatures at northern latitudes over the 24 years in this study. These shifts in annual cycles of terrestrial vegetation appear to have a distinct geographical zonality and are dependent upon latitudinal changes in climatic variables. More conspicuous changes in overall vegetation productivity and the seasonal phase of ecosystems have been observed in Eurasia compared to North America, largely because of a more rapid rise in temperature. Our results state that changing climate boosts plant growth at northern latitudes, but also alters the phase and seasonal variations of the annual cycle of terrestrial ecosystems.

A simple and novel self-assembly based process is presented in this paper for the fabrication of gold triangular nanocavity arrays. This process combines nanosphere lithography (NSL) with some standard MEMS technologies. A carboxylated polystyrene (PS) nanosphere bilayer with a relatively large area is fabricated on silicon wafer as the starting template by spin-coating. Oxygen plasma etching, metal deposition and lifting-off of the PS upper layer are then orderly carried out for the formation of triangular space, which is made up of Cr film and the remaining PS nanoparticles. Then silicon etching is used to transfer the triangle pattern onto the silicon wafer. Finally, a 50 nm thick gold layer is deposited on the pattern to fabricate gold triangular nanocavity arrays. With this strategy, both the period and the cavity size can be adjusted independently. This will allow the tuning of the optical properties for desired application.

A capacitive accelerometer with triangle cross-section beam fabricated by anisotropic wet etching of (100) silicon is presented in this paper. The feature of this accelerometer is that eight suspension beams with triangle cross-section are formed by anisotropic wet etching of (100) silicon in TMAH solution, without heavy boron doping or Si-Si bonding. When the width of beam is decided, the beam’s geometry is determinate. The formation procedure of the triangle cross-section beam is analyzed in detail. Through this beam-fabrication approach, the beam’s thickness can be well controlled by beam’s width and intrinsic stress in the beams is minimized. Accelerometers with different sensitivities can be easily fabricated by varying the width of the beams. For a device with 23 μm width beams, the resonance frequency and the quality factor are 644 Hz and 32, respectively. The sensitivity of accelerometer is measured as 2 V•g-1.

Abstract: The spatial scan statistic (SaTScan) has become one of the most popular methods for detecting and evaluating spatial clusters. However, this method can only identify circular or elliptical clusters and is not a good fit for the detection of irregularly shaped clusters. Numerous methods have since been proposed to solve this problem. Nevertheless, if multiple clusters coexist, these methods may not identify the correct situation, because the interference between clusters can easily lead to a tree-like shaped cluster and cause confusion in the results. In this paper, we propose an Ant Colony Optimization based Multiple Cluster Detection (ACOMCD) algorithm, which combines classical SaTScan with the ant colony optimization (ACO) approach. In the initial stage, SaTScan is first used to mark the candidate cluster areas according to the significance of their maximum likelihood evaluations. Then ACO-based scan statistic is carried out separately on these candidate clusters to identify their natural shapes. The algorithm was designed for spatial regional count data only. Comparisons between ACOMCD, SaTScan, GaScan (genetic algorithm-based scan statistic), and FleXScan (flexibly shaped spatial scan statistic) on three kinds of simulated datasets show that ACOMCD performs the best in simultaneously determining the exact number of clusters and identifying multiple irregularly shaped clusters. A case study on esophageal cancer in eastern China further validates the correctness and effectiveness of ACOMCD. [Copyright &y& Elsevier]

In order to study the effect of rock fracture distributions on stability of tunnel, the effect of joints with different strike dip, the size and density was considered by using probability and statistics method. Based on the Monte Carlo random simulation, the statistical network model of 2D jointed rockmass was established to describe and characterize jointed rock mass. On the basis of this, the numerical code RFPA2D is employed to analyze effect of fracture dip angle on the tunnel stability. Numerical results show that the fracture distribution has a little effect on tunnels failure mechanism and failure type of tunnel because the failure of tunnel in the jointed rockmass is similar to the one without joints and fissures. However with the change of the fracture dip angle, the loading capacity of the tunnel in the jointed rockmass varies accordingly.