scholarly journals Low-temperature deicing means

2015 ◽  
Vol 7 (3) ◽  
Author(s):  
Andrey Kochetkov ◽  
Leonid Yankovskiy ◽  
Sofia Arganuchina ◽  
Igor' Shashkov ◽  
Alеksandr Bobkov
Keyword(s):  
Low Temperature ◽  
Calcium Chloride ◽  
Low Temperatures ◽  
Raw Materials ◽  
Volume Ratio ◽  
Crystalline Hydrate ◽  
Winter Maintenance ◽  
Effective Application ◽  
Different Types ◽  
Main Component

Low-temperature deicing means belongs to area of winter maintenance of buildings and constructions, can be applied to winter maintenance of highways, various open surfaces subject to influence or different types of manifestations of low temperatures. The objective is reached by that in deicing means containing granules from chlorides, each of granules is executed in the form of pressed mix of chloride calcium and chloride of potassium, at a volume ratio in a granule of chloride potassium and chloride calcium from 2:1 to 4:1, thus between particles of chloride potassium and chloride calcium connecting layer from calcium chloride crystalline hydrate is placed. Thus in a granule volume of chloride potassium makes 45-85%, the volume of waterless chloride calcium of 25-45%, thickness of a connecting layer from calcium chloride crystalline hydrate - 0,01-0,1 mm, and size of a granule makes 2-7 mm. The declared set of signs allows to expand the range of effective application of protigololedny means, to provide its reduction in cost and efficiency of application as a component of deicing material of chloride potassium extracted on a place. The reached efficiency was expressed in expansion of temperature of application in range from 0° to -10°C in comparison with application temperature (as main component) chloride calcium (from -10°C and below). Besides, declared deicing means allows to reduce cost of production of PGM developed from local raw materials by 20-40%.

scholarly journals STUDY OF THE KINETICS OF HYDRATION STRUCTURING AND THE PROPERTIES OF LIME-BELITIC BINDERS BASED OF MARL

Vestnik MGSU ◽  
2016 ◽  
pp. 62-68
Author(s):  
Aleksey Dmitrievich Zhukov ◽  
Marat Orynbaevich Asamatdinov ◽  
Bakhtiyar Chimbergenovich Nurymbetov ◽  
Sharibay Nauryzbaevich Turemuratov
Keyword(s):  
Chemical Composition ◽  
Low Temperature ◽  
Physicochemical Properties ◽  
Calcium Oxide ◽  
Raw Materials ◽  
High Strength ◽  
Dicalcium Silicate ◽  
Different Types ◽  
Materials Used ◽  
Kinetics Of

Lime-belite binder is obtained by low-temperature firing of natural marl, marling or sanding limestone and artificial lime-silica mixtures. The binder with calcium oxide also contains significant amounts of dicalcium silicate and some others materials, the composition and quantity of which depend on the chemical composition and firing temperature of the raw materials used. The authors investigated the kinetics of hydration structures and physicochemical properties of lime-based binders on the basis of belitic marl from Akburly and Porlytau. The formation of resistance is associated not only with the formation of the system of different types of structures - coagulation and crystallization, with the transition of the first to the second, but also with the different stages of formation of crystal structures. The possibility of using lime-belitic binders for the preparation of high-strength products of autoclave hardening is proved. The autoclaved binders used in the manufacture of sand-lime products are prepared with the use of mixtures consisting of 60...70 % lime-belite binder and 30...40 % ground quartz sand.

Impact inoculum dosage of lactic acid bacteria on oat and wheat silage fermentation at ambient and low temperatures

2018 ◽  
Vol 69 (12) ◽  
pp. 1225
Author(s):  
Miao Zhang ◽  
Zhongfang Tan ◽  
Xiaojie Wang ◽  
Meiyan Cui ◽  
Yanping Wang ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Low Temperature ◽  
Lactic Acid Bacteria ◽  
Ambient Temperature ◽  
Low Temperatures ◽  
Raw Materials ◽  
Antimicrobial Properties ◽  
Alpine Regions ◽  
Silage Quality

Lactic acid bacteria (LAB) can be used as silage additives to ensure rapid and vigorous fermentation at early stages of ensiling. We predicted that the optimal LAB inoculation dosage for forage at ambient temperature (15–38°C) would be different from that at cold temperature (4°C). In this study, Lactobacillus plantarum QZ227, isolated from a wheat landrace in alpine regions of Qinghai, China, and commercial L. plantarum FG1 were used as inoculum, with sterile water as control. The effects of inoculum dosage on the fermentation quality of oat (Avena sativa L. cv. Qinghai) and wheat (Triticum aestivum L. cv. Yumai No. 1) silage at ambient temperature (15–38°C) and at 4°C were investigated in laboratory experiments. Little or no improvement in silage quality occurred upon increasing the inoculum dosage at ambient temperature. By contrast, a lower pH and NH3-N content, and a higher LAB count and lactic acid content, were observed at 4°C. Furthermore, the growth of Escherichia coli was inhibited effectively at the lower temperature, and silage quality was positively correlated with increasing inoculum dosage (P<0.05). These results suggest that increasing the inoculum dosage could improve the quality of silage at lower temperatures of 4°C, whereas an appropriate dosage was a key factor for silage at ambient temperature. In this study, oat forage could be used as raw materials for ensiling only at low temperature but was not suitable for ensiling at ambient temperature without wilting due to the high moisture content (86.55%). QZ227 isolated from the roots of wheat in alpine regions displayed superior antimicrobial properties against yeast at ambient temperature and E. coli at 4°C compared with commercial strain FG1. This is the first study to explore the effects of inoculum dosage on silage quality at low temperatures, and provides a basis for low-temperature silage technologies.

scholarly journals Preparation and Performance Evaluation of Reforming Prehydrogenation Catalyst Used for Blending Inferior Coking Gasoline

2020 ◽  
Vol 4 (3) ◽  
Author(s):  
Tiezhen Zhang ◽  
◽  
Yungang Jia ◽  
Famin Sun ◽  
Liang Wang ◽  
...  
Keyword(s):  
Performance Evaluation ◽  
Low Temperature ◽  
High Performance ◽  
Active Component ◽  
Raw Materials ◽  
Volume Ratio ◽  
Good Activity ◽  
Reaction Pressure ◽  
Excellent Activity ◽  
And Performance

A reforming prehydrogenation catalyst suitable for blending inferior coking gasoline was developed by the supporter modification, selection and optimization of active component. The catalyst has high performance of hydrodesulfurization, hydrodenitrification and olefin saturation at low temperature. The catalyst has good activity and strong adaptability to raw materials, At reaction pressure of 2.0MPa, hydrogen-oil volume ratio of 200:1, LHSV of 5.0h-1, reaction temperature of 268-280℃, it can process the prehydrogenation raw materials blending inferior hydrocoking gasoline (20-50%), and the generated oil can meet the requirements of reforming feed. The results of 1500h activity stability test show that the catalyst has excellent activity stability.

Transcription factor CaNAC1 regulates low-temperature-induced phospholipid degradation in green bell pepper

2019 ◽  
Author(s):  
Xi-man Kong ◽  
Qian Zhou ◽  
Xin Zhou ◽  
Bao-dong Wei ◽  
Shu-juan Ji
Keyword(s):  
Transcription Factor ◽  
Low Temperature ◽  
Low Temperatures ◽  
Chilling Injury ◽  
Membrane Lipid ◽  
Mobility Shift ◽  
Low Temperature Storage ◽  
Bell Peppers ◽  
Main Component ◽  
Phospholipid Degradation

Abstract Phospholipids constitute the main component of biomembranes. During low-temperature storage and transportation of harvested bell peppers, chilling injury participates in pepper decay. A primary cause of pepper chilling injury is phospholipid degradation. In this study, three phospholipase D (PLD)-encoding genes were identified from bell peppers and their activity were analyzed under cold stress. Low temperatures induced strong accumulation of the CaPLDα4 transcript, suggesting that this induction contributes to the phenomenon of phospholipid degradation and cell membrane destruction at 4°C. Low temperatures also significantly induced the transcript amounts of NAM-ATAF1/2-CUC2 (NAC) domain transcription factor. CaNAC1 was found to possess the capacity to interact with the promoter of CaPLD4 in a yeast one-hybrid screen. Furthermore, electrophoretic mobility shift and ß-glucuronidase reporter assays demonstrated that CaNAC1 binds to the CTGCAG motif in the CaPLDα4 promoter, thereby activating its transcription and controlling phospholipid degradation. The ubiquitination sites of the CaNAC1 protein were also characterized by liquid chromatography tandem-mass spectrometry. In conclusion, CaNAC1 is a transcriptional activator of CaPLDα4 and is suggested to participate in membrane lipid degradation of bell peppers when stored at low temperature.

scholarly journals Traditional and Modern Protective Media for the Low-Temperature Bacteria Preservation

2011 ◽  
pp. 36-40
Author(s):  
I. V. Gracheva ◽  
T. V. Valova ◽  
G. V. Grigor'eva
Keyword(s):  
Low Temperature ◽  
Dimethyl Sulfoxide ◽  
Low Temperatures ◽  
Pathogenic Bacteria ◽  
Effective Application ◽  
Regulatory Guidelines ◽  
Protein Origin

Presented are the literature data on the efficiency of bacteria preservation at temperatures ranging from -20 to -196 °C in the protective media containing such cryoprotectors as glycerol, dimethyl sulfoxide, carbo-hydrates, substances of protein origin specified by regulatory guidelines. Most of the focus is on the publications reporting the results of the long-term bacteria preservation at sub-zero temperatures, optimization of the protective media for pathogenic bacteria, and usage of the compounds with potential cryoprotective activity. Noted is the necessity for approbation of the specified protective media for the conserved bacteria species at the applied preserving temperatures. One of the approaches to the enhancement of the low-temperature preservation techniques is a search for natural protectors, which can provide for surviving of bacteria in the unfavorable conditions, including low temperatures, and a search for possibility to integrate these natural protectors into the cryoprotective media. Displayed are the results of effective application of glycerol-betaine, and polysaccharides of Arctic microorganisms for the low-temperature bacteria preservation.

In situ Tensile Experiments at Low Temperatures on Niobium Single Crystals by H.V.E.M.

1975 ◽  
Vol 33 ◽  
pp. 58-59
Author(s):  
F. H. Louchet ◽  
L. P. Kubin
Keyword(s):  
Electron Microscope ◽  
Transition Temperature ◽  
Low Temperature ◽  
Slip System ◽  
Low Temperatures ◽  
Tensile Axis ◽  
Image Intensifier ◽  
Screw Dislocations ◽  
Source Operation

Experiments have been carried out on the 3 MeV electron microscope in Toulouse. The low temperature straining holder has been previously described Images given by an image intensifier are recorded on magnetic tape.The microtensile niobium samples are cut in a plane with the two operative slip directions [111] and lying in the foil plane. The tensile axis is near [011].Our results concern:- The transition temperature of niobium near 220 K: at this temperature and below an increasing difference appears between the mobilities of the screw and edge portions of dislocations loops. Source operation and interactions between screw dislocations of different slip system have been recorded.

Point and planar defects in the iron sulfide compounds Fe1-xS

1984 ◽  
Vol 42 ◽  
pp. 434-435
Author(s):  
Thao A. Nguyen
Keyword(s):  
Low Temperatures ◽  
Direct Evidence ◽  
Iron Sulfide ◽  
Planar Defects ◽  
Selective Area ◽  
Vacancy Ordering ◽  
Different Types ◽  
Lattice Images ◽  
The Subject ◽  
Beam Lattice

It is well known that the large deviations from stoichiometry in iron sulfide compounds, Fe1-xS (0≤x≤0.125), are accommodated by iron vacancies which order and form superstructures at low temperatures. Although the ordering of the iron vacancies has been well established, the modes of vacancy ordering, hence superstructures, as a function of composition and temperature are still the subject of much controversy. This investigation gives direct evidence from many-beam lattice images of Fe1-xS that the 4C superstructure transforms into the 3C superstructure (Fig. 1) rather than the MC phase as previously suggested. Also observed are an intrinsic stacking fault in the sulfur sublattice and two different types of vacancy-ordering antiphase boundaries. Evidence from selective area optical diffractograms suggests that these planar defects complicate the diffraction pattern greatly.

INVAR M93

Alloy Digest ◽  
2008 ◽  
Vol 57 (1) ◽  
Keyword(s):  
Fracture Toughness ◽  
Low Temperature ◽  
Physical Properties ◽  
Tensile Properties ◽  
Low Temperatures ◽  
Bend Strength ◽  
Temperature Performance ◽  
Ni Content ◽  
Precision Alloys ◽  
Ni Alloy

Abstract Invar is an Fe-Ni alloy with 36% Ni content that exhibits the lowest expansion of known metals from very low temperatures up to approximately 230 deg C (445 deg F). Invar M93 is a cryogenic Invar with improved weldability. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear and bend strength as well as fracture toughness and fatigue. It also includes information on low temperature performance as well as forming and joining. Filing Code: FE-143. Producer or source: Metalimphy Precision Alloys.

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

2019 ◽  
Vol 32 (1) ◽  
pp. 143-151 ◽  
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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