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In this study, simulation of a silicon sensitive element (SE) of capacitive accelerometer using the analytical model to obtain the optimized sensitivity of the capacitive type accelerometer structure with comb-drives is presented. The objective of the article is to consider the design of the silicon SE, deformation results, mechanical stresses and capacitance changes between the gaps of comb-drives on the silicon SE of MEMS-based capacitive type accelerometer. At first, the structural design of the silicon SE of MEMS-based capacitive accelerometer structure with the sensitive comb-drives using the software of SOLIDWORKS is given. The deformation results and mechanical stresses of the SE of MEMS-based capacitive accelerometer along the working axes of X and Y, which play an essential role for calculation of capacitance changes between the comb-drives of the structure by using the ANSYS software are analyzed. The deformation results of the silicon SE at the temperature ranges from –40 to 80°С with an acceleration range of 300 g by using the program of ANSYS are considered. Capacitance changes between comb-drives based on the deformation results on the silicon SE of capacitive accelerometer with the membrane of 40 µm thickness when exposed to the structure of the SE with the acceleration ranges from 50 to 300 g by using the program of Ansys Maxwell are studied. To enhance the sensitivity of the capacitive comb type accelerometer, the presented design is more appropriate for manufacturing of sensitive devices in the field of MEMS sensors. [ABSTRACT FROM AUTHOR]

The nonlinear baseband electromagnetic pulses of a wide spectrum that covers the lower part of terahertz (THz) range are investigated theoretically in the paraelectric crystals like SrTiO3 at the moderately low temperatures 50–200 K. The frequency dispersion is important there. The dominating nonlinearity of the crystal is cubic. To increase the influence of the nonlinearity, the focusing of the input baseband pulses of small amplitudes has been applied. The main attention is paid to the three-dimensional (3D) geometry of focusing of the input baseband pulses. The nonlinear focusing of input long baseband pulses by the exciting antenna results in the formation of extremely short baseband pulses of subpicosecond durations. Under 3D focusing the peak values of the nonlinear focused pulses are bigger and their durations are shorter than ones under 2D focusing, but the transverse localization is stronger under 2D focusing. [ABSTRACT FROM AUTHOR]

The influence of the soldering temperature on the performance of flip-chip light-emitting diodes (FC-LED) filaments soldered with SAC0307 has been investigated. Scanning electron microscopy (SEM) images, void rates, shearing force, junction temperature, steady-state voltage, blue light luminous flux, and luminous efficiency were measured to characterize the filament performance. The microstructure of the fracture surface after shear failure of the FC-LED filament joints soldered at 250°C and 270°C showed the lowest percentage of voids and was smoother than for the other groups. The shearing force of the FC-LED filament solder joints formed at 250°C and 270°C was higher than that for the other three groups, but the shearing force of all five groups of solder joints exceeded 200 gf. The steady-state voltage and junction temperature of the 250°C and 270°C FC-LED filaments were lower than those of the other three groups, and the blue light luminous flux of the 250°C and 270°C FC-LED filaments was higher than for the other three groups. In conclusion, the FC-LED filaments exhibited good photoelectric performance and thermal reliability when using soldering temperatures between 250°C and 270°C. [ABSTRACT FROM AUTHOR]

Temperature is one of the key factors influencing the viral disease development in plants. In this study effect of temperature on SYMMV accumulation and systemic movement was studied in French bean, mungbean and soybean cultivars by keeping them at temperatures range 22-25 °C, 26-29 °C and 30-33 °C. The proliferation of the virus under these conditions was confirmed through symptomatology, DAC-ELISA, RT-PCR with coat protein specific primers and RT-qPCR. French bean plants displayed symptoms by 12dpi at low temperature (22-25 °C) and by 3dpi at medium temperatures (26-29 °C) with continuous increase in viral accumulation from 0 to 24dpi. At high temperatures (30-33 °C), French bean did not show symptoms up to 12dpi but the virus accumulated and moved systemically. However, there was a decline in viral copy number after 12dpi. Mungbean plants showed mottling, mosaic and puckering symptoms at 22-25 °C and 26-29 °C and necrotic symptoms at 30-33 °C. Irrespective of temperature there was an increase in viral accumulation in mungbean from 0 days to 24dpi. Soybean plants showed veinal mild mottling at low and medium temperatures where as no peculiar symptom expression observed at high temperatures. Soybean also showed the reduction of viral copy number from 12 days to 24dpi at low and medium temperatures and from 6 days to 24dpi at high temperatures. These results indicate that temperature played an important role in SYMMV accumulation, movement and symptom expression in these three leguminous plant species. This study also demonstrates that SYMMV can replicate and spread in mungbean plants irrespective of the temperature. [ABSTRACT FROM AUTHOR]

A good indoor thermal climate is important. To reduce energy demands for space heating, individual metering and billing (IMB) for space heating costs is common, though not yet in Sweden. To obtain a better picture of the thermal climate conditions, the distribution of the measured indoor temperatures was investigated in each apartment in 14 apartment blocks with a total of 419 apartments. All blocks had an IMB system for space heating with a traditional feed-forward control. In the studied buildings, temperatures were measured in each living room and each bedroom, and were registered at 2.1 m over floor level, every 15 min over a period of 12 months. Seasonal mean temperatures, standard deviations, skewness, and kurtosis are presented for apartment blocks. For one, with 75 apartments, these values are monthly, and for January and April, the temperature range for each apartment is presented in boxplots. It can be concluded that there are variations in temperature between different apartments: both variations in temperature levels and in temperature ranges. The overall conclusions are that differences in indoor temperature are achievable for different apartments in an apartment block with a certain set point temperature and that the temperatures are not dependent on an apartment's location in the building. Both the building owner's goal to keep a certain average temperature for energy saving reasons, and the tenants' goals, possibility to vary the indoor temperature at individual apartment level, seems to be possible to reach. The measured temperatures are close to being normally distributed, though they have a mild negative skewness and a mild kurtosis during heating periods. The results support that indoor temperatures can be modeled as normally distributed in energy simulations of buildings. Further, it can be seen that temperature variations follow the seasons. The temperatures on individual apartment level show that there is a tendency for warm apartments to be warm all the year round and vice versa. There are also daily variations, with a magnitude of 0.3-0.4 °C and with 0.1-0.3 °C difference between weekdays and weekends. Every single indoor temperature measurement for a whole year covering all seasons as a function of outdoor temperature is presented in iso-plots. Temperature levels are mainly within the limits of standards for thermal comfort, thus showing that a thermal satisfying indoor climate is met in these apartment blocks with IMB. It also seems that it was possible to achieve the desired temperatures irrespective of the apartment's location. [ABSTRACT FROM AUTHOR]

An investigation has been carried out to identify the trends in maximum, minimum and mean temperatures and temperature range over the Indian land mass during the winter (January, and February), pre-monsoon (March-May), southwest monsoon (June-September) and post-monsoon (October-December) seasons by using high resolution daily gridded data set prepared by India Meteorological Department for the period of 1969-2005. It has been observed that the maximum temperatures over the west coast of India show rising trend in winter, southwest monsoon and post-monsoon seasons but the maximum temperatures do not show any significant trend over the other parts of the country. Minimum temperatures show increasing trend over the North Indian states in all seasons and they show an increasing trend over the west coast of India in winter and southwest monsoon seasons. Mean temperature shows an increasing trend over the west coast of India during winter and southwest monsoon seasons. Decreasing trend is observed in the temperature range over North India in all seasons due to increasing trend in minimum temperature. [ABSTRACT FROM AUTHOR]

The effect of thermal deformation on the strength of models of thermal protective coating at temperatures above 1000 °C is studied. The coating is of shell type and made of a carbon/carbon (C/C) composite with varying winding angle. The physical and mechanical characteristics of the composite were determined experimentally in simulated real conditions using equipment available at the Institute for Problems of Strength. The stress-strain state of a thermal protective cylindrical shell of length 340 mm, mid-surface radius 90 mm, and thickness 10 mm subject to heating is solved using the three-dimensional theory of elasticity. The results obtained allow determining the stress state of a thermal protective shell-type coating depending on the type and winding angle of the carbon reinforcement within the temperature range from 20 to 1200 °C. [ABSTRACT FROM AUTHOR]

The role of seed germination in contributing to species ecological breadth and geographic distribution is still a matter of debate. Here, we attempted to relate seed germination requirements with ecological breadth in 12 bromeliad species from heterogeneous montane vegetation in southeastern Brazil. Seeds were set to germinate under both light and dark conditions at a broad range of temperatures to determine the breadth of the germination niche. We ran a RLQ analysis based on the matrices of species occurrence, environmental parameters and germination traits and found a significant association between germination traits, and the characteristics of sites where adult plants occur. The variation of germination responses to environmental factors was not random with habitat-generalist plants having broader germination niches and habitat-specialist plants having narrower germination niches. The RLQ analysis showed that substrate moisture and light environment were the most important factors correlated with germination traits. Phylogenetic niche conservatism appears to play a role in the patterns found here, especially in the Tillandsioideae. There is an association between the regeneration niche of a species and its ecological range, and this also provides support for the idea that the regeneration niche may help assemble plant species into heterogeneous, species-rich communities. [ABSTRACT FROM AUTHOR]

Thermally induced error of nanopositioning systems is rarely studied specifically because most researchers strictly limit the ambient temperature in order to ignore the influences of thermal deformation. However, the control cost of a narrow temperature range is too high for widely application. This paper is addressed at modeling and compensation of thermal error with the purpose of ensuring the positioning accuracy with an extended temperature range. The finite element analysis and contrast experiments with different temperature ranges reveal the significant impact of temperature variation on positioning precision. A polynomial model based on the genetic algorithm is implemented to describe the relationship between deviations and temperatures. By utilizing the parametric study, the optimal parameters of the genetic algorithm are determined. Based on the thermal model, a compensation system has been developed. A constant proportional-integral-derivative (PID) controller and a single-neuron PID controller are employed for compensation, respectively. The results demonstrate that the single-neuron PID controller can effectively restrain thermal error and guarantee the location accuracy with extended temperature range. The positioning precision of the positioning stage with compensation system and temperature range of 20 + 0.3°C is improved to 12 nm, while the one of the original system with temperature range of 20 ± 0.01°C is 31 nm. [ABSTRACT FROM AUTHOR]

The new MC-10 magnetic structure analyzer is intended for the determination of different characteristics of materials and products by measuring coercive force. The MC-10 structure analyzer is compared with its older analogues: the KPM-Ц-K2M magnetic structure analyzer and KИM-2M coercimeter. [ABSTRACT FROM AUTHOR]

Ecological niche modeling based on surface seawater (SST) and atmospheric (AT) temperature records was used to predict the potential range of distribution of Crassostrea gigas, focusing on the South American coast as a study case. In its native range, the species maintains self-sustaining populations at thermal regimes with mean SST ranging from 14.0° to 28.9°C for the warmest month and from −1.9° to 19.8°C for the coldest month of the year. Settlement is also constrained to mean AT varying between 15° and 31°C for the warmest month and between −23° and 14°C for the coldest month of the year. Latitudinal limits for the species’ distribution in South America predicted by the analysis of AT regimes were Valdivia-Chiloe Island (39.8º–42.0°S, Chile) and Pisco (13.4°S, Peru) on the Pacific coast, and San Julian port (49.3°S) (Argentina) and Garopaba-Rio Grande (28.0°–32.0°S, Brazil) on the Atlantic coast. Geographical limits of distribution predicted by analysis of SST regimes were Chiloe Island (42.0°S, Chile) and Mancora (4.1°S, Peru) on the Pacific coast, and Puerto Deseado ria (47.7°S, Argentina) and Paranaguá (25.7°S, Brazil) on the Atlantic coast. Therefore, SST regimes would expand the potential range on the Pacific coast equatorward relative to AT. [ABSTRACT FROM AUTHOR]

Thermodynamic conditions (first of all, temperature) are the main dynamic factors in the transformation process of ferrous to ferric iron (TFFI). TFFI usually takes place within a temperature range of 473–843 K (most active at temperatures above 673 K) and does not require presence of the oxidizing agents above 673 K. Analysis of the chemical composition of different rocks and minerals indicates that only for some sedimentary rocks is the relative content of ferrous iron oxide less than its value in magnetite, and this value is minimal for oceanic sediments. The relative content of ferrous iron oxide in oceanic magmatic rocks exceeds this value in continental magmatic rocks and depends on the rate of rock cooling. An investigation of the role of the titanium oxide content of different rocks on stability of ferrous iron oxide against its transformation to ferric iron oxide shows that a significant correlation ( r = 0.79) does exist between the relative content of ferrous iron oxide and ratio of TiO2/Fe2O3. Temperature within the solar nebula at location of the Earth was within the temperature range of the TFFI. During the Earth accretion and its early evolution, ferric iron oxide was unstable and most likely did not exist. The first magnetic minerals containing ferric iron could have appeared only after the Earth’s surface had cooled below ∼843 K. The formation of the first Algoma-type banded iron formations could be used as a marker of the Earth’s surface cooling below ∼843 K. [ABSTRACT FROM AUTHOR]

The sums over states of the atoms and singly and doubly charged ions of rare-earth elements that are required for a theoretical study of thermochemical processes in high-temperature plasma spectral sources are calculated in the temperature range 2500–12,000 K. [ABSTRACT FROM AUTHOR]