Enhancement of resistance to chlorine poisoning of Sn-modified MnCeLa catalysts for chlorobenzene oxidation at low temperature

AbstractCapacitors, resistors and inductors are surface mounted components on circuit boards, which occupy up to 70% of the circuit board area. For selected applications, these passives are packaged inside green ceramic tape substrates and sintered at temperatures over 700°C in a co-fired process. These high temperature processes are incompatible with organic substrates, and low temperature processes are needed if passives are to be embedded into organic substrates. A new high permeability dual-phase Nickel Zinc Ferrite (DP NZF) core fabricated using a low temperature sol-gel route was developed for use in embedded inductors in organic substrates. Crystalline NZF powder was added to the sol-gel precursor of NZF. The solution was deposited onto the substrates as thin films and heat-treated at different temperatures. The changes in the microstructures were characterized using XRD and SEM. Results showed that addition of NZF powder induced low temperature transformation of the sol-gel NZF phase to high permeability phase at 250°C, which is approximately 350°C lower than transformation temperature for pure NZF sol gel films. Electrical measurements of DP NZF cored two-layered spiral inductors indicated that the inductance increased by three times compared to inductors without the DP NZF cores. From microstructural observations, the increase is correlated with the changes in microstructural connectivity of the powder phase.

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GERMINATION AND VIGOUR IN SEEDS OF THE COWPEA IN RESPONSE TO SALT AND HEAT STRESS

Revista Caatinga ◽

10.1590/1983-21252019v32n115rc ◽

2019 ◽

Vol 32 (1) ◽

pp. 143-151 ◽

Cited By ~ 1

Author(s):

Luma Rayane de Lima Nunes ◽

Paloma Rayane Pinheiro ◽

Charles Lobo Pinheiro ◽

Kelly Andressa Peres Lima ◽

Alek Sandro Dutra

Keyword(s):

Salt Stress ◽

Heat Stress ◽

High Temperature ◽

Low Temperature ◽

Vigna Unguiculata ◽

Salt Concentration ◽

Dry Weight ◽

Germination Percentage ◽

Different Types ◽

Different Temperatures

ABSTRACT Salinity is prejudicial to plant development, causing different types of damage to species, or even between genotypes of the same species, with the effects being aggravated when combined with other types of stress, such as heat stress. The aim of this study was to evaluate the tolerance of cowpea genotypes (Vigna unguiculata L. Walp.) to salt stress at different temperatures. Seeds of the Pujante, Epace 10 and Marataoã genotypes were placed on paper rolls (Germitest®) moistened with different salt concentrations of 0.0 (control), 1.5, 3.0, 4.5 and 6.0 dS m-1, and placed in a germination chamber (BOD) at temperatures of 20, 25, 30 and 35°C. The experiment was conducted in a completely randomised design, in a 3 × 4 × 5 scheme of subdivided plots, with four replications per treatment. The variables under analysis were germination percentage, first germination count, shoot and root length, and total seedling dry weight. At temperatures of 30 and 35°C, increases in the salt concentration were more damaging to germination in the Epace 10 and Pujante genotypes, while for the Marataoã genotype, damage occurred at the temperature of 20°C. At 25°C, germination and vigour in the genotypes were higher, with the Pujante genotype proving to be more tolerant to salt stress, whereas Epace 10 and Marataoã were more tolerant to high temperatures. Germination in the cowpea genotypes was more sensitive to salt stress when subjected to heat stress caused by the low temperature of 20°C or high temperature of 35°C.

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A Method for Predicting the Behavior of Plastics at Different Temperatures

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1039.107 ◽

2014 ◽

Vol 1039 ◽

pp. 107-111

Author(s):

Yang Chen ◽

Gui Qin Li ◽

Bin Ruan ◽

Xiao Yuan ◽

Hong Bo Li

Keyword(s):

High Temperature ◽

Low Temperature ◽

Constitutive Model ◽

Research And Development ◽

Mechanical Behavior ◽

Plastic Material ◽

Different Temperatures ◽

Plastic Parts

The mechanical behavior of plastic material is dramatically sensitive to temperature. An method is proposed to predict the mechanical behavior of plastics for cars, ranging from low-temperature low temperature ≤-40°C to high temperature ≥80°C. It dominates the behavior of plastic material based on improved constitutive model in which the parameters adjusted by a series of tests under different temperatures. The method is validated with test and establishes the basis for research and development of plastic parts for automobile as well.

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Ageing in embryos from wheat grains stored at different temperatures: oxidative stress and antioxidant response

Functional Plant Biology ◽

10.1071/fp11046 ◽

2011 ◽

Vol 38 (7) ◽

pp. 624 ◽

Cited By ~ 8

Author(s):

Carmelina Spanò ◽

Stefania Bottega ◽

Roberto Lorenzi ◽

Isa Grilli

Keyword(s):

Oxidative Stress ◽

Low Temperature ◽

Seed Viability ◽

Storage Period ◽

Antioxidant Response ◽

Protective Role ◽

Native Page ◽

Wheat Grains ◽

Different Temperatures ◽

Enzymatic Machinery

In the present work we studied oxidative stress as an important cause of seed deterioration during ageing in embryos from durum wheat grains stored at room temperature and at low temperature (10°C). The protective role of low temperature on seed viability was confirmed. The increase of hydrogen peroxide content during dry storage was strongly correlated with the decrease of germinability. Ascorbate and glutathione showed a good correlation with grain germinability and significantly increased upon imbibition, in particular in embryos from viable grains. Ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione peroxidase (GPX) and catalase (CAT) were studied quantitatively (enzymatic assays). APX, GR, and GPX were also studied qualitatively by native PAGE. The enzymes were active in dry, still viable, embryos whereas no activity was detected in non-viable embryos. With the exception of APX, all enzymatic activities decreased upon imbibition. The study of grains stored in different conditions indicated a negative correlation between the efficiency of the antioxidant enzymatic machinery and the age of the grain. The differences detected in differently stored materials confirmed that both germination parameters and the length of storage period are important in determining grain condition.

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Short-period (Si14 / Si0.75 Ge0.25)20 Superlattices for the Growth of High-quality Si0.75 Ge0.25

MRS Proceedings ◽

10.1557/proc-765-d6.2 ◽

2003 ◽

Vol 765 ◽

Author(s):

M.M. Rahman ◽

T. Tambo ◽

C. Tatsuyama

Keyword(s):

Low Temperature ◽

Alloy Layer ◽

Buffer Layers ◽

Threading Dislocations ◽

Strained Layers ◽

Temperature Growth ◽

Low Temperature Growth ◽

Defect Sites ◽

Short Period ◽

Different Temperatures

AbstractIn the present experiment, we have grown 2500-Å thick Si0.75Ge0.25 alloy layers on Si(001) substrate by MBE process using a short-period (Si14/Si0.75Ge0.25)20 superlattice (SL) as buffer layers. In the SL layers, first a layer of 14 monolayers (MLs) of Si (thickness about 20Å) then a thin layer of Si0.75Ge0.25 (thickness 5-6Å) were grown. This Si/(Si0.75Ge0.25) bilayers were repeated for 20 times. The buffer layers were grown at different temperatures from 300-400°C and the alloy layers were then grown at 500°C on the buffer layers. The alloy layer showed low residual strain (about -0.16%) and smooth surface (rms roughness ~15Å) with 300°C grown SL buffer. Low temperature growth of Si in SL layer introduces point defects and low temperature growth of Si1-xGex in SL layer reduces the Ge segregation length, which leads to strained SL layer formation. Strained layers are capable to make barrier for the propagation of threading dislocations and point defect sites can trap the dislocations.

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Experimental study on the compression characteristics of soft soil based on low temperature effect

Journal of Engineering Research ◽

10.36909/jer.8266 ◽

2021 ◽

Vol 9 (4B) ◽

Author(s):

Jian Zhang ◽

◽

Chunpeng Han ◽

Jiayi Tian ◽

Qingjie Dong ◽

...

Keyword(s):

Low Temperature ◽

Phase Change ◽

Compression Test ◽

Variable Temperature ◽

Soft Soil ◽

Test Methods ◽

Variable Load ◽

Compression Tests ◽

Different Temperatures ◽

Freezing Condition

Based on the characteristics of long annual freezing time and short suitable construction period of soft soil in cold region, this paper discusses the feasibility of foundation treatment of soft soil in freezing-thawing layer under freezing condition. The deformation characteristics of soft soil in freezing-thawing layer in Hulunbuir area in China are studied by using two compression test methods, namely, constant temperature and variable load (CTVL) test, variable temperature and variable load (VTVL) test. The compressibility indexes under different temperatures and consolidation pressures are obtained. The research shows that the freezing-thawing soft soil has large compressibility, the maximum strain of CTVL test is 19.89%, and the maximum compression of VTVL test can reach 18.16%. The results of CTVL compression tests show that when the soil temperature is in the range of severe phase change (-1.5℃-0℃), the temperature change has the greatest influence on the compression coefficient of soil. The result of VTVL compression test shows that some additional deformation occurs under the action of low temperature. The additional deformation is further increased when the soil is under high consolidation pressure and in the severe phase change (-1.5℃-0℃).

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THE EFFECT OF TEMPERATURE ON THE EXPRESSION OF FACTORS GOVERNING RUST REACTION IN A CROSS BETWEEN TWO VARIETIES OF TRITICUM VULGARE

Canadian Journal of Research ◽

10.1139/cjr31-063 ◽

1931 ◽

Vol 5 (2) ◽

pp. 200-207 ◽

Cited By ~ 1

Author(s):

J. B. Harrington

Keyword(s):

Low Temperature ◽

Genetic Factors ◽

The Other ◽

Effect Of Temperature ◽

Puccinia Graminis ◽

Genetic Studies ◽

Triticum Vulgare ◽

Susceptibility Factors ◽

Different Temperatures ◽

Genetic Hypothesis

Two random populations of F2 plants of the cross Marquillo × Marquis were tested for the reaction of their F3 seedling progenies to form 21 of Puccinia graminis tritici in the greenhouse, at average daily temperatures of 69.7° F. (the warm test) for one population, and 60.6° F. (the cool test) for the other. In both tests Marquis was susceptible and Marquillo was resistant. In the "warm test" ten families of a total of 781 were resistant. In the "cool test" five families of a total of 301 were susceptible. In both cases the results fitted a 63:1 ratio excellently, indicating the operation of three main genetic factors for rust reaction. A genetic hypothesis is proposed that explains the results on the basis of the influence of low temperature in curtailing the action of three susceptibility factors A, B and C carried by Marquis. The results indicate that genetic studies on characters which are easily influenced by environmental conditions should be made under controlled conditions, after ascertaining in advance the general effects of different temperatures, etc., upon the hybrid material to be used.

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Experimental Study on the Creep Behavior of Red Sandstone under Low Temperatures

Advances in Civil Engineering ◽

10.1155/2019/2328065 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Yongjun Song ◽

Leitao Zhang ◽

Huimin Yang ◽

Jianxi Ren ◽

Yongxin Che

Keyword(s):

Mechanical Properties ◽

Low Temperature ◽

Deformation Characteristics ◽

Red Sandstone ◽

Rock Samples ◽

Uniaxial Creep ◽

Deformation Properties ◽

Accelerated Creep ◽

Different Temperatures

In cold regions, the deformation characteristics and long-term mechanical properties of rocks under low-temperature conditions are considerably different from those in other regions. To study the deformation characteristics and long-term mechanical properties of rocks in a low-temperature environment and the effect of different temperatures, we perform a multilevel loading-unloading uniaxial creep test on red sandstone samples and obtain the creep curves at different temperatures (20°C, −10°C, and −20°C). The results demonstrate that the total strain at each temperature can be divided into instantaneous and creep strains; the instantaneous strain includes instantaneous elastic and plastic strains, and the creep strain includes viscoelastic and viscoplastic strains. Temperature has a significant effect on the deformation properties of red sandstone. A decrease in temperature reduces the instantaneous and creep deformations of the rocks at all levels of stress. In addition, a decrease in temperature exponentially attenuates the total creep and viscoplastic strains of the rocks. 0°C is a critical point for the reduction of the total creep and viscoplastic strains of the rocks. When the temperature is greater than 0°C, the total creep and viscoplastic strains of the rocks decrease rapidly and linearly with decrease in temperature; however, when the temperature is less than 0°C, the decrease in the total creep and viscoplastic strains of the rocks is slow. The steady-state creep rate of the rock samples decreases with decrease in temperature, whereas the creep duration increases with decrease in temperature, especially in the case of the accelerated creep stage. The accelerated creep durations of the rock samples S4 (20°C) and S7 (–10°C) are 0.07 h and 0.23 h, respectively.

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Ceramization Mechanism of Ceramizable Silicone Rubber Composites with Nano Silica at Low Temperature

Materials ◽

10.3390/ma13173708 ◽

2020 ◽

Vol 13 (17) ◽

pp. 3708

Author(s):

Penghu Li ◽

Haiyun Jin ◽

Shichao Wei ◽

Huaidong Liu ◽

Naikui Gao ◽

...

Keyword(s):

Low Temperature ◽

Flexural Strength ◽

Silicone Rubber ◽

Glass Frit ◽

Nano Silica ◽

Linear Contraction ◽

Ceramic Phase ◽

Ceramic Samples ◽

Different Temperatures ◽

Similar Materials

Ceramizable composite is a kind of polymer matrix composite that can turn into ceramic material at a high temperature. It can be used for the ceramic insulation of a metal conductor because of its processability. However, poor low-temperature ceramization performance is a problem of ceramizable composites. In this paper, ceramizable composites were prepared by using silicone rubber as a matrix. Ceramic samples were sintered at different temperatures no more than 1000 °C, according to thermogravimetric analysis results of the composites. The linear contraction and flexural strength of the ceramics were measured. The microstructure and crystalline phase of ceramics were analyzed using scanning electron microscope (SEM) and X-ray diffraction (XRD). The results show that the composites turned into ceramics at 800 °C, and a new crystal and continuous microstructure formed in the samples. The flexural strength of ceramics was 46.76 MPa, which was more than twice that of similar materials reported in other research sintered at 1000 °C. The maximum flexural strength was 54.56 MPa, when the sintering temperature was no more than 1000 °C. Moreover, glass frit and nano silica played important roles in the formation of the ceramic phase in this research. A proper content of nano silica could increase the strength of the ceramic samples.

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The Melting of Free-Drifting Icebergs

Annals of Glaciology ◽

10.3189/s0260305500017092 ◽

1980 ◽

Vol 1 ◽

pp. 119-122 ◽

Cited By ~ 60

Author(s):

D. S. Russell-Head

Keyword(s):

Low Temperature ◽

Water Temperature ◽

Population Studies ◽

Sea Water ◽

Surface Shape ◽

Different Temperatures

Blocks of ice with the proportions of tabular icebergs have been observed melting in water of different temperatures and salinities. The sub-surface shape adopted by the blocks melting in water of the same salinity as sea-water was typically a ‘bath-tub’ one. The basal and mean-side melt rates were of a similar value. The melt rates obtained in the laboratory for icebergs in water of a low temperature match those inferred from population studies of Antarctic icebergs. The melt rate is proportional to the water temperature above the onset of freezing raised to the power 1.5 and melt rates at 18°C are likely to be greater than one metre per day.

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