scholarly journals Effect of Temperature Gradient of Grain Storage on Migration and Distribution of Three Pests

2021 ◽  
Vol 2 (7) ◽  
pp. 632-640
Author(s):  
Zhenya Mu ◽  
Jin Wang ◽  
Yan Zhang ◽  
Xiaozhe Qi ◽  
Li Li ◽  
...  
Keyword(s):  
Temperature Gradient ◽  
Tribolium Castaneum ◽  
Storage Temperature ◽  
Sitophilus Oryzae ◽  
Effect Of Temperature ◽  
Grain Storage ◽  
Rhizopertha Dominica ◽  
Peripheral Area ◽  
C 30 ◽  
The Right

Temperature gradients were set at the opposite sides of the grain storage: 25°C-30°C, 20°C-30°C, 20°C-35°C, 30°C-30°C. The migration and distribution of imago of Sitophilus oryzae, Rhizopertha dominica and Tribolium castaneum in the grain storage were observed. The results showed significant differences that the distribution trends of imago of Sitophilus oryzae, Rhizopertha dominica and Tribolium castaneum within a certain grain storage temperature gradient (p < 0.05). The temperature gradient of grain storage is 25°C-30°C. Tribolium castaneum tends to gather in the 30°C side area of grain storage, while Sitophilus oryzae has no obvious trend, while Rhizopertha dominica tends to gather in the 25°C. The temperature gradient of grain storage is 20°C-30°C. Both Tribolium castaneum and Sitophilus oryzae tend to gather in the 30°C side area of grain storage, while Rhizopertha dominica tends to gather in the 20°C. The temperature gradient of grain storage is 20°C-35°C. Tribolium castaneum, Sitophilus oryzae and Rhizopertha dominica all tend to gather in the area on the side of grain storage at 35°C. The temperature gradient of grain storage is 30°C-30°C, and there is no obvious trend for Tribolium castaneum. Rhizopertha dominica tends to gather in the 30°C area on the left side of grain storage, while Sitophilus oryzae tends to gather in the 30°C area on the right side of grain storage. After cooling down, it was found that Sitophilus oryzae tended to gather in the center of the grain storage, while the Tribolium castaneum had no obvious trend, and the Rhizopertha dominica tended to gather in the peripheral area of the grain storage.

scholarly journals Theoretical Effect of Temperature on Threshold in the Hodgkin-Huxley Nerve Model

1966 ◽  
Vol 49 (5) ◽  
pp. 989-1005 ◽  
Author(s):  
Richard Fitzhugh
Keyword(s):  
Relaxation Time ◽  
Relaxation Times ◽  
Giant Axon ◽  
Temperature Curve ◽  
Effect Of Temperature ◽  
Threshold Temperature ◽  
Ionic Conductances ◽  
And Shifts ◽  
The Right ◽  
Increasing Temperature

In the squid giant axon, Sjodin and Mullins (1958), using 1 msec duration pulses, found a decrease of threshold with increasing temperature, while Guttman (1962), using 100 msec pulses, found an increase. Both results are qualitatively predicted by the Hodgkin-Huxley model. The threshold vs. temperature curve varies so much with the assumptions made regarding the temperature-dependence of the membrane ionic conductances that quantitative comparison between theory and experiment is not yet possible. For very short pulses, increasing temperature has two effects. (1) At lower temperatures the decrease of relaxation time of Na activation (m) relative to the electrical (RC) relaxation time favors excitation and decreases threshold. (2) For higher temperatures, effect (1) saturates, but the decreasing relaxation times of Na inactivation (h) and K activation (n) factor accommodation and increased threshold. The result is a U-shaped threshold temperature curve. R. Guttman has obtained such U-shaped curves for 50 µsec pulses. Assuming higher ionic conductances decreases the electrical relaxation time and shifts the curve to the right along the temperature axis. Making the conductances increase with temperature flattens the curve. Using very long pulses favors effect (2) over (1) and makes threshold increase monotonically with temperature.

scholarly journals The Effect of Cooling Agent on Stress and Deformation of Charge-loaded Cast Pallets

2017 ◽  
Vol 17 (4) ◽  
pp. 13-18
Author(s):  
A. Bajwoluk ◽  
P. Gutowski
Keyword(s):  
Heat Transfer ◽  
Heat Treatment ◽  
Temperature Gradient ◽  
Effect Of Temperature ◽  
Transfer Coefficients ◽  
Heat Transfer Coefficients ◽  
Cooling Conditions ◽  
Cooling Agent ◽  
Stress And Deformation ◽  
A Charge

Abstract The results of research on the effect of the type of cooling agent used during heat treatment and thermal-chemical treatment on the formation of temperature gradient and stress-deformation distribution in cast pallets, which are part of furnace accessories used in this treatment, are disclosed. During operation, pallets are exposed to the effect of the same conditions as the charge they are carrying. Cyclic thermal loads are the main cause of excessive deformations or cracks, which after some time of the cast pallet operation result in its withdrawal due to damage. One of the major causes of this damage are stresses formed under the effect of temperature gradient in the unevenly cooled pallet construction. Studies focused on the analysis of heat flow in a charge-loaded pallet, cooled by various cooling agents characterized by different heat transfer coefficients and temperature. Based on the obtained temperature distribution, the stress distribution and the resulting deformation were examined. The results enabled drawing relevant conclusions about the effect of cooling conditions on stresses formed in the direction of the largest temperature gradient.

scholarly journals Effect of temperature gradient on heavy quark anti-quark potential using gravity dual model

2020 ◽  
Author(s):  
S Ganesh ◽  
M Mishra
Keyword(s):  
Temperature Gradient ◽  
Gluon Plasma ◽  
Effect Of Temperature ◽  
Dual Model ◽  
Thermal Gradients ◽  
Imaginary Time ◽  
Thermal Systems ◽  
Naturally Occurring ◽  
Quark Potential ◽  
Stationary Approximation

Abstract Thermal systems have traditionally been modeled via Euclideanized space by analytical continuation of time to an imaginary time. We extend the concept to static thermal gradients by recasting the temperature variation as a variation in the Euclidean metric. We apply this prescription to determine the Quark anti-Quark potential in a system with thermal gradient. A naturally occurring QCD medium with thermal gradients is a Quark Gluon Plasma (QGP). However, the QGP evolves in time. Hence, we use a quasi-stationary approximation, which is applicable only if the rate of time evolution is slow. Hence the application of our proposal to a Quark anti-Quark potential in QGP can be seen as a step towards a more exact theory which would incorporate time varying thermal gradients. The effect of a static temperature gradient on the Quark anti-Quark potential is analyzed using a gravity dual model. A non-uniform black string metric is developed, by perturbing the Schwarzchild metric, which allows to incorporate the temperature gradient in the dual AdS space. Finally, an expression for the Quark anti-Quark potential, in the presence of a static temperature gradient, is derived.

Effect of Temperature Gradient on the Mechanical Buckling Resistance of FGM Shallow Arches

2014 ◽  
Author(s):  
M. Bateni ◽  
M. R. Eslami
Keyword(s):  
Temperature Gradient ◽  
Thermal Environment ◽  
Mechanical Load ◽  
Functionally Graded ◽  
Effect Of Temperature ◽  
Power Law Distribution ◽  
Concentrated Load ◽  
Shallow Arches ◽  
Buckling Resistance ◽  
Graded Material

This work presents a closed form investigation on the effect of temperature gradient on the buckling resistance of functionally graded material (FGM) shallow arches. The constituents are assumed to vary smoothly through the thickness of the arch according to the power law distribution and they are assumed to be temperature dependent. The arches subjected to the both uniform distributed radial load and central concentrated load and both boundary supports are supposed to be pinned. The temperature field is approximated by one-dimensional linear gradient through the thickness of the arch and the displacement field approximated by classical arches model. Also, Donnell type kinematics is utilized to extract the suitable strain-displacement relations for shallow arches. Adjacent equilibrium criterion is used to buckling analysis, and, critical bifurcation load is obtain in the complete presence of pre-buckling deformations. Results discloses the usefulness of using the FGM shallow arches in thermal environment because the temperature gradient enhances the buckling resistance of these structures when they are subjected to a lateral mechanical load.

scholarly journals Optimization of cultural conditions for submerged state fermentation of di-gested biogas slurry for production of lignocellulolytic enzymes using Phanaerochaete chrysosporium MTCC 787

2017 ◽  
Vol 9 (3) ◽  
pp. 1729-1734
Author(s):  
Ajit Kaur ◽  
Urmila Gupta Phutela
Keyword(s):  
Inoculum Size ◽  
Effect Of Temperature ◽  
Biogas Slurry ◽  
Cultural Conditions ◽  
Maximum Value ◽  
Microbial Products ◽  
End Use ◽  
C 30 ◽  
Novel Concept ◽  
Optimization Of Fermentation

Growing environmental concerns and increasing demands from end-use sectors have increased the glob-al market for microbial products. Optimizations of production parameters hold great importance for the industry. The present study was aimed at optimization of submerged state fermentation conditions for production of lignocelluloly-tic enzymes from digested biogas slurry by Phanaerochaete chrysosporium MTCC 787. Enzyme activities for differ-ent enzymes i.e. endoglucanase, exoglucanase, β-glucosidase; xylanase and mannanase; laccase, lignin peroxidase and manganese peroxidise, using P. chrysosporium MTCC 787 were maximum at 50% concentration of digested slur-ry and showed maximum value of xylanase i.e. 187.41U/ml. Effect of temperature (25°C, 30°C and 35°C) on lignocellu-losic bioconversion showed that at 30°C, maximum value of manganese peroxidise (167.5 U/ml) was obtained. High-est enzyme activites were obtained at selected inoculum size i.e. 10⁷spores/ml, e.g. 85.29 U/ml xylanase was ob-tained. Incubation period of 8 days and pH of 7.0 came out to be best conditions for P. chrysosporium MTCC787 to produce maximum enzyme activity e.g. xylanase 95.47U/ml at pH 7.0 and xylanase 144.96U/ml at 8 day incu-bation.This work presents a novel concept in optimization of fermentation process to produce lignocellulolytic en-zymes as this work is focussed on utilization of digested biogas slurry as a substrate for enzyme production and enhancement of the production with microbial source, which is environment friendly.

scholarly journals Insectos plaga de granos almacenados. Impacto en la seguridad alimentaria del municipio Las Tunas, Cuba

2016 ◽  
pp. 23
Author(s):  
Dayami Laguna Ávila ◽  
Carlos Pupo Feria ◽  
Gladia González Ramírez ◽  
Alina Espeek González
Keyword(s):  
Food Security ◽  
Food Safety ◽  
Tribolium Castaneum ◽  
Insect Pests ◽  
Sitophilus Oryzae ◽  
Main Species ◽  
Palabras Clave ◽  
Pest Insects ◽  
Stored Grains ◽  
Bruchus Pisorum

Insects pest of stored grains. Impact on food security of Las Tunas municipality, Cuba Resumen Con el objetivo de determinar las especies de insectos plaga en granos almacenados para la obtención de información que contribuyan al manejo de sus poblaciones y minimizar las pérdidas que influyen en la seguridad alimentaria de la población, se realizó un estudio en la Unidad 639 de la Empresa Mayorista de Productos Alimenticios del municipio Las Tunas, Cuba, en el período de enero del año 2011 hasta diciembre del año 2013. En el estudio se colectaron e identificaron 26 especies de insectos plaga en las naves, distribuidas en 19 géneros y 12 familias, pertenecientes a tres órdenes, de ellas, 23 especies cosmopolitas y de amplia distribución en Cuba. Las principales especies de insectos plaga encontradas fueron Tribolium castaneum; Ahasverus advena; Bruchus pisorum; Sitophilus oryzae; Ephestia sp. y Liposcelis sp. El hospedante con mayor frecuencia de aparición de las especies de insectos plaga fue el arroz, seguido por el frijol y el chícharo. Palabras clave: almacenes; cereal; plagas Abstract In order to determine the species of insect pests in stored grains to obtain information that contribute to the management of their populations and minimize losses that influence the food security of the population, a study was carried out in Unit 639 of the Company Wholesaler of Food Products of the municipality Las Tunas, Cuba, in the period from January 2011 until December 2013. The study collected and identified 26 species of insect pests in the ships, distributed in 19 genera and 12 families, belonging to three orders, of which 23 species are cosmopolitan and widely distributed in Cuba. The main species of pest insects found were Tribolium castaneum; Ahasverus advena; Bruchus pisorum; Sitophilus oryzae; Ephestia sp. and Liposcelis sp. The host with the highest frequency of appearance of insect pests was rice, followed by beans and peas. Keywords:  Insect pests; storage; food safety.

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