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This research explored the effects of the addition of low doses of aromatic plant biomasses (APBs) on the microbial community and carbon source decomposition in compost. APBs were reported to be capable of altering the composition and function of microbial communities in many environments. However, the effects of APB addition on the compost carbon source metabolism, a process highly linked to the microbial community of compost, were still unclarified, especially when added in small doses. In this study, Cinnamomum camphora biomass was added to the initial compost of Stropharia rugosoannulata cultivation materials, in a mass ratio of 0%, 1%, 2%, and 3%, respectively. The variation in the carbon source contents, the microbial community composition, and the related enzyme activities of the end compost products were measured. The results showed that Cinnamomum camphora biomass addition significantly altered the content of cellulose, hemicellulose, lignin, and protein of compost products, but did not affect the starch and soluble sugar content. Meanwhile, the addition significantly reduced lignin peroxidase and cellulase activities, but increased xylanase and laccase activities, and had no effect on magnesium peroxidase and polyphenol oxidase. Both the bacterial and fungal community compositions were significantly altered by the addition, though the alpha diversity indexes were not significantly changed. The relative abundance of Proteobacteria and Sordariomycetes was significantly increased by the addition, while Acidobacteria, Chloroflexi and Eurotiomycetes significantly decreased. Structural equation modeling found that the variation in the bacterial community composition (0.464 standard total effect) provided a higher contribution to lignocellulose degradation, rather than the fungal community (0.365 standard total effect). A co-occurrence network analysis further revealed that the trade-off between lignin peroxidase and laccase activity, which was induced by the relative abundance variation in Proteobacteria, Actinobacteriota, and Firmicute members, was the main driver in the lignocellulose decomposition variation. This research provides a new insight into the recycling of APB waste, and offers an improvement to mushroom cultivation material compost.

Ecosystem degradation is a process during which different ecosystem components interact and affect each other. The microbial community, as a component of the ecosystem whose members often display high reproduction rates, is more readily able to respond to environmental stress at the compositional and functional levels, thus potentially threatening other ecosystem components. However, very little research has been carried out on how microbial community degradation affects other ecosystem components, which hampers the comprehensive understanding of ecosystems as a whole. In this study, we investigated the variation in a soil microbial community through the extinction gradient of an ectomycorrhizal species (Tricholomas matsutake) and explored the relationship between microbial community degradation and ectomycorrhizal species extinction. The result showed that during degradation, the microbial community switched from an interactive state to a stress tolerance state, during which the interactivity of the microbial community decreased, and the reduced community interactions with T.matsutake marginalized it from a large central interactive module to a small peripheral module, eventually leading to its extinction. This study highlights the mechanisms of T.matsutake extinction due to the loss of soil microbial community interactivity, offering valuable information about soil microbial community degradation and the plant ectomycorrhizal species conservation.

Soil microbial communities play irreplaceable roles in regulating environment. However, global climate change induced extreme weather events were reported capable reshape microbial community composition, which exert possible influences on the environment regulation function. Unfortunately, the compositional response of microbial community to extreme weather events and the potential factors regulating this response were still scarcely explored up to date. To fill the gap, here we sampled soils from 5 different type ecosystems and conducted a simulated extreme high-temperature stress experiment. The results showed that the complex ecosystems (like forests) had higher richness reduction than simple ecosystems (like bare land) during stress stage, most bacterial community richness kept decreasing while most fungal community richness were relatively unchanged during recovery stage. Despite the fungal communities in different types of ecosystems showed different and specific changes in the face of stress during the stress and recovery stage, the relative abundances of α-Proteobacteria were enhanced by stress in simple ecosystems but decreased in complex ecosystems, and the recovery stage of simple ecosystems were characterized by the trade-off between α-, β- and γ-Proteobacteria while complex ecosystems were by Firmicutes. Further analysis showed that the simple ecosystems tend to possess higher resistance and lower resilience while the complex ecosystems displayed the opposite trend. Resistance and resilience were significantly negatively correlated. Structural equation modeling showed that richness provided a higher contribution to bacterial and fungal resistance than to resilience while nutrients provided a higher contribution to resilience than to resistance. This research explored the influence of extreme high temperature stress on soil microbial community and the resistance and resilience of microbial community different types ecosystems to the stress, highlighted the respectively greater relative contribution of richness and nutrients offered to resistance and resilience, which provided valuable information for future prediction on microbial community response to climatic stresses.

Most of the existing non-contact flame temperature measurement methods rely on the ideal thermal-optical excitation model, which has a great influence on temperature measurement accuracy. Therefore, based on element doping and energy spectrum analysis, this study proposes a novel two-dimensional (2-D) estimation method for flame temperature and emissivity distribution. The element doping method and laser-induced breakdown spectroscopy (LIBS) are introduced into the temperature field test. The external doped element whose spectral radiation characteristics are easy to be analyzed, is regarded as the measured particles to describe the flame temperature distribution from the side. And LIBS is used to analyze and select the doped element, and further determine the effective working wavelength of the optical camera. Besides, the relationship between spectral radiance and emissivity ( $L$ - $\varepsilon$ ) of doped samples is obtained by the emissivity calibration experiment. Then, the 2-D temperature and emissivity distributions can be estimated. Infrared thermograph is used to verify the accuracy of temperature measurement, the measurement error between calculated and standard values is not more than 5%. The experimental results of the oxygen-ethanol combustion flame show that this method can be well applied to the similar temperature measurement.

Mountain glaciers are retreating at an unprecedented rate due to global warming. Glacier retreat is widely believed to be driven by the physiochemical characteristics of glacier surfaces; however, the current knowledge of such biological drivers remains limited. An estimated 130 Tg of organic carbon (OC) is stored in mountain glaciers globally. As a result of global warming, the accelerated microbial decomposition of OC may further accelerate the melting process of mountain glaciers by heat production with the release of greenhouse gases, such as carbon dioxide (CO2 ) and methane. Here, using short-term aerobic incubation data from the forefield of Urumqi Glacier No. 1, we assessed the potential climate feedback mediated by soil microbiomes at temperatures of 5°C (control), 6.2°C (RCP 2.6), 11°C (RCP 8.5), and 15°C (extreme temperature). We observed enhanced CO2 -C release and heat production under warming conditions, which led to an increase in near-surface (2 m) atmospheric temperatures, ranging from 0.9°C to 3.4°C. Warming significantly changed the structures of the RNA-derived (active) and DNA-derived (total) soil microbiomes, and active microbes were more sensitive to increased temperatures than total microbes. Considering the positive effects of temperature and deglaciation age on the CO2 -C release rate, the alterations in the active microbial community structure had a negative impact on the increased CO2 -C release rate. Our results revealed that glacial melting could potentially be significantly accelerated by heat production from increased microbial decomposition of OC. This risk might be true for other high-altitude glaciers under emerging warming, thus improving the predictions of the effects of potential feedback on global warming.

Solid rocket motor (SRM) temperature is an important physical parameter for which there is no reliable in situ measurement device, apart from a thermocouple, for such a high temperature environment apart. In this study, an ultrasonic temperature measurement system was designed with an iridium-rhodium-40% alloy waveguide. Laboratory experiments showed that the device obtained ultrasonic signals up to 1800 °C with a temperature fitting curve from room temperature to 1800 °C. The thermometer also operated stably under high temperature and produced a repeatable calibration curve, at 97% repeatability. An error band was obtained with 95% confidence. At temperatures above 1000 °C, sensitivity gradually increased to a maximum of 0.0035 µs/°C. A corresponding application structure was established for an SRM before subjecting the sensor to a temperature test experiment. The temperature–time curve obtained detected a peak temperature at 1744 °C.

The biodiversity of fungi, which are extremely important in maintaining the ecosystem balance in alpine lakeside wetlands, has not been fully studied. In this study, we investigated the fungal communities of three lakeside wetlands from different altitudes in the Qinghai&ndash, Tibet Plateau and its edge. The results showed that the fungi of the alpine lakeside wetland had higher species diversity. Functional annotation of fungi by FUNGild software showed that saprophytic fungi were the most abundant type in all three wetlands. Further analysis of the microbial phylogenetic molecular ecological network (pMEN) showed that saprophytic fungi are important species in the three wetland fungal networks, while symbiotic fungi and pathotrophic fungi have different roles in the fungal networks in different wetlands. Community diversity was high in all three lakeside wetlands, but there were significant differences in the composition, function and network structure of the fungal communities. Contemporary environmental conditions (soil properties) and historical contingencies (geographic sampling location) jointly determine fungi community diversity in this study. These results expand our knowledge of fungal biodiversity in the alpine lakeside wetlands.

Mountainous alpine ecosystems are sensitive to global change, where soil nutrient content would potentially vary under current climate change background, and thus possibly influence the activity of nitrifiers and denitrifiers, as well as N2O emissions. However, within mountainous alpine ecosystems, the potential variation of soil nutrients under current global change and the consequence to N2O emission from nitrification and denitrification are still unclarified, hampering a comprehensive understanding of the feedback mechanisms between the nitrogen cycle and climate change. In order to fill this knowledge gap, we selected alpine grasslands at three different elevations and investigated the distribution and environmental drivers of nitrifiers and denitrifiers. The results showed that the lowest elevation site tended to have higher total phosphorus (TP) accumulation within the topsoil. The abundance of functional groups, emission of CO2 and N2O, and the N2O/CO2 ratio showed a decreasing trend along elevation. TP was the greatest influence on denitrifier composition (nosZ/narG and nirS/nirK ratios) and considerably influenced nitrifier composition (AOA/AOB ratio), and was significantly correlated to the N2O/CO2 ratio. In microcosms of soils from the highest elevation site, TP addition decreased the ratios of nosZ/narG, nirS/nirK, and AOA/AOB, and increased N2O/CO2 ratio and N2O emission, thus contributing to positive climate change feedback. This study indicates the potential for change within the nitrifier and denitrifier communities under current climate change, and highlights the role TP plays in governing nitrification and denitrification in mountainous alpine ecosystems.

Iridium-rhodium is generally applied as a thermocouple material, with max operating temperature about 2150 °C. In this study, a ultrasonic temperature measurement system was designed by using Iridium-rhodium (60%Ir–40%Rh) alloy as an acoustic waveguide sensor material, and the system was preliminarily tested in a high-temperature oxidation environment. The result of ultrasonic temperature measurement shows that this system can indeed work stably in high-temperature oxidation environments. The relationship between temperature and delay time of ultrasonic thermometry up to 2200 °C was illustrated. Iridium-rhodium materials were also investigated in order to fully elucidate the proposed waveguide sensor’s performance in a high-temperature oxidation environment. This system lays a foundation for further application of high-temperature measurement.

Soil aggregates play a vital role in regulating soil biological processes such as those involved in microbial nitrogen (N) reactions. Here, a microcosm experiment was conducted to evaluate the differences in nitrous oxide (N2O) emissions and their associated microbial communities among varying soil aggregates (4–8, 2–4, and

The properties of rocks can be greatly affected by seepage hydrocarbons in petroleum-related mud volcanoes. Among them, the color of sedimentary rocks can reflect the changes of sedimentary environment and weathering history. However, little is known about the microbial communities and their biogeochemical significance in these environments. In this study, contrasting rock samples were collected from the Aiqigou mud volcano on the southern margin of the Junggar Basin in Northwest China as guided by rock colors indicative of redox conditions. The physicochemical properties and mineral composition are similar under the same redox conditions. For example, the content of chlorite, muscovite, quartz, and total carbon were higher, and the total iron was lower under reduced conditions compared with oxidized environments. High-throughput sequencing of 16S rRNA gene amplicons revealed that different functional microorganisms may exist under different redox conditions, microbes in oxidized conditions have higher diversity. Statistical analysis and incubation experiments indicated that the microbial community structure is closely related to the content of iron which may be an important factor for color stratification of continental sedimentary rocks in the Aiqigou mud volcano. The interactions between organics and iron-bearing minerals mediated by microorganisms have also been hypothesized.

Iridium-rhodium is generally applied as a thermocouple material, with max operating temperature about 2150 °C. In this study, a ultrasonic temperature measurement system was designed by using Iridium-rhodium (60%Ir-40%Rh) alloy as an acoustic waveguide sensor material, and the system was preliminarily tested in a high-temperature oxidation environment. The result of ultrasonic temperature measurement shows that this system can indeed work stably in high-temperature oxidation environments. The relationship between temperature and delay time of ultrasonic thermometry up to 2200 °C was illustrated. Iridium-rhodium materials were also investigated in order to fully elucidate the proposed waveguide sensor's performance in a high-temperature oxidation environment. This system lays a foundation for further application of high-temperature measurement.

A new time constant measurement means of the surface temperature sensor is proposed, in which a high frequency modulated high power CO2 laser acts as the driving source. The measurement system is designed and practiced in thermocouples with different temperature ranges. It is proved that the system can be used to measure transient surface temperature sensor which be with a time response from the sub-millisecond level to the second level, and the temperature provided by the driving source can range from the room temperature to the high temperature.© (2010) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Thermal inertia and finite heat conduction make the acquired temperature from temperature sensor be not reliable enough. So, it is necessary to make a dynamic calibration to the sensor. The frequency-response characteristics of high speed radiation thermometer surpass that of the temperature sensor; therefore it can be used as the reference value to calibrate the latter and let system error is corrected. The traceable dynamic calibration method is used to calibrate CHAL-010 thermocouple (manufactured by OMEGA Company). The thermocouple's time constant as well as error correction value of dynamic temperature measurement is obtained from it. The traceability is accomplished successfully through unbroken chain of comparisons with appropriate standard at the system.

Based on classical PSO ( abbreviated for particle swarm optimization ) algorithm and quantum theory, this paper proposes an improved quantum particle swarm optimization algorithm - zbQPSO ( abbreviated for zhao Bezier quantum-behaved PSO) algorithm. Identical particle system is introduced to update the position of particle, hyper-chaotic thought introduced to chaotic search for every particle and average search length thought of search algorithm was introduced to improve the full and local searching ability, convergence rate and calculating precision for elementary particle swarm. The calculation results for classical function show that capability of improved algorithm is superior to classical PSO algorithm and quantum PSO algorithm.

This paper describes recent measurements of the emission characteristics of laser-driven photoelectric thin films and their potential uses in microscopy. Preparation of organic film photocathodes on doped silicon and copper substrates is described. Kinetic energy spreads of photoelectrons from these emitters have been measured as a function of current density, film thickness, substrate type and laser wavelenght. It appears that film thickness and smoothness have little effect on the energy distribution, but the energy spread does increase at high current densities, probably because of space charge, and reducing the illuminating wavelenght from 337 to 266 nm causes a significant increase in energy spread. With pulsed laser illumination, the emission current can be increased by selecting a thickness which exploits an optical standing wave resonance made possible by the substrate reflectance. The current densities obtained with these cathodes are compared to values desired for applications in microscopy, and comparison is also made to other choices of photoemitters and laser illuminators. Performance limitations imposed by heating of the films and by space charge are discussed.

In the paper, a principle is proposed, that is, a high frequency modulated high power CO 2 laser is used as the driving source to heat up the sensor. Using the continual beam and the pulsed beam sent out by the same laser in the same system to carry on the static calibration of the infrared detector and the dynamic calibration of the temperature sensor to be checked, the differences in the environment of the sensor installing and the error caused by the change of thermo physical property can be avoided. Thus the difficult problem of traceable temperature dynamic calibration is solved. Tellurium-cadmium-mercury infrared detector which has good response to the CO 2 laser beam of 10.6μm wavelength is used to measure the surface temperature time (72μs) excited by the CO 2 laser. This dynamic calibration system was used to test the response times of two kinds of thermocouples. The experimental results have shown that this calibration system can be used to calibrate transient surface temperature sensor with a time response of the seconds to sub-milliseconds order and 2000°C. Many thermocouples of company Omega have been tested on the system. The experimental results show that the new calibration method can be used to calibrate surface temperature sensors.

A dynamic calibration system for transient surface temperature detectors is introduced. In this system a pulse laser and a continuous laser are used as excitation sources. The static and dynamic calibrations have been carried out respectively with the use of the continuous CO2 laser and Nd-glass pulse laser. Several quick response thermocoupleshave been tested on the system. The experimental results have shown that this calibration system can be used to calibratetransient surface temperature detectors with a time response on order of microseconds.Keyword dynamic calibration, pulse laser, effipsoidal reflector, infrared detector, transient surface temperature detector 1JNTRODUCTION In the field of weapons, the measurement of transient surface temperature is important to the research of the performance and service life of guns. It is the circumstances of high temperature and high pressure in the bore of a gunthat makes the measurement oftransient surface temperature difficulty. At present, there are many methods of measuringtransient surface temperature. These methods can be divided roughly into two categories: the contact method and thenon-contact method. For example, the contact detectors specially designed for measuring the temperature field of flameand the surface temperatures at some parts of space shuttle when back to atmosphere are used in US. The thermocouple,which is made of NiCrINiSi, used to measuring transient temperature of bore wall of the 7.62mm guns was reported inUs and its response time can reach 1O s 11.In the measurement of transient temperature, we can also apply some non-contact methods, such as laser interferometry, spectrometry, etc.

Photoelectric emission is of current interest for its applications to microscopy as well as for its possible use as an electron source for integrated circuit lithography, particle accelerators, x-ray sources, and free electron lasers. These diverse applications share a common requirement for electron sources of relatively high brightness. A significant difficulty to be overcome results from the fact that available light sources have photon energies too low to induce photoelectron emission from the materials of most interest. In particular, surfaces which emit electrons under illumination by visible or near ultraviolet light are limited to a small number of materials based on highly reactive metals. To explore a possible alternative, we have investigated the emission of electrons from organic compounds possessing an intermediate electron energy level which assists the emission process through multiphoton absorption. The energy spreads of electrons emitted from these surfaces are important because beam spreading and aberrations in an instrument can depend on the energy distribution. Here we describe transverse energy measurements of photoelectrons from thin films of 2,2‘-binaphthyl on silicon and copper substrates. This coating material was chosen because of its high two-photon quantum yield.