scholarly journals Mpemba Effect- the Effect of Time

2021 ◽  
Author(s):  
Jianan Wang
Keyword(s):  
Energy Density ◽  
Flow Rate ◽  
Time Characteristic ◽  
Reasonable Explanation ◽  
Energy Flows

This paper concludes that " time is one of the properties of energy, which is the flow rate of energy from object to space or from space to object. When energy flows from object to space, the time on an object is proportional to the energy density inside the object and inversely proportional to the energy density of the space in which the object is located. When energy flows from space to object, the time on an object is inversely proportional to the energy density inside the object and is proportional to the energy density of the space in which the object is located” Using this time characteristic, the Mpemba effect and "inverse" Mpamba effect are analyzed and a reasonable explanation is given.

scholarly journals Distribution of energy density of Dirac field in the closed universe

1970 ◽  
Vol 9 (9) ◽  
pp. 1-3
Author(s):  
SK Sharma ◽  
U Khanal
Keyword(s):  
Energy Density ◽  
Finite Energy ◽  
Negative Energy ◽  
Field Energy ◽  
Dirac Field ◽  
Closed Universe ◽  
Frw Universe ◽  
Energy Current ◽  
Large Structures ◽  
Energy Flows

The behavior of the energy of the free Dirac field in the closed FRW universe has been looked at. It is generally expected that the comoving energy density for the particles is conserved. Although this expectation is true for the massless fields, it is not for the massive ones. So, there is a finite energy current in any finite sized volume of the universe. The energy current is positive throughout for lowest state, n = 0. For n = 1, however, there occurs negative energy flow near r = π/2. So energy flows out of the region. It may be expected that the two regions, on either sides may become disjoint over time, but this can be confirmed only after studying the time evolution. If confirmed, this could explain the process of fragmentation of large structures. Larger n appears to produce larger number of such density contrasts. Key words: Closed Universe; Dirac field; Energy DensityDOI: http://dx.doi.org/10.3126/sw.v9i9.5492SW 2011; 9(9): 1-3

Numerical Investigation of Effect of Blade Surface Slot on the Performance and Flow Field of a Low Speed Centrifugal Fan

2020 ◽  
Author(s):  
HaoGuang Zhang ◽  
FeiYang Dong ◽  
XuDong Zhang ◽  
WuLi Chu
Keyword(s):  
Boundary Layer ◽  
Flow Field ◽  
Flow Rate ◽  
Flow Condition ◽  
Low Energy ◽  
Centrifugal Fan ◽  
Blade Surface ◽  
Suction Surface ◽  
Flow Losses ◽  
Energy Flows

Abstract The main objective of this study is to understand the mechanisms of affecting the performance and flow field of a low speed centrifugal fan with blade surface slots. In the investigation, a spanwise slot, which is placed within the range of about 60% to 100% of the blade span, is applied to each blade surface of the impeller, and the partial blade pressure and suction surfaces for each blade are connected via the blade surface slot. The full-passage unsteady numerical results indicate that the performance of fan including the volute is improved among the overall mass flow rate by applying the blade surface slot, and the blade surface slots generate about an enhancement of 3.6% for the total pressure improvement, an improvement of 2.6% for the efficiency respectively at the design mass flow rate. The flow field analyses show that the injecting flows discharging from the blade surface slots can encourage the low energy flows near the blade suction surface in some blade passages. Hence, the boundary layer separations of the blade suction surface are restrained by the injecting flows, and the flow condition in the passag is considerately improved. Moreover, the adverse effect caused by the low energy flows is very serious in the partial blade passages near the shroud, while the flows in the blade surface slots have few positive effect on the low energy flows. So, the improvement by the slots on the flow fields is very small near the shroud region. Because the boundary layer separations on the blade suction surface are absent in most of the blade passages at about 60% of the blade span, the flows emerging from the slots have passive effects on the passage mainstreams. Further, in the case of blade surface slots, there is an obvious vortex near the blade trailing edge at about 60% of the blade span, and the vortex is close to the blade suction surface at some instants. As a result, the wake flow losses in the passage become large with the application of the slots. Briefly, within the slotted span range, the improvement of the flow field in the blade passages becomes large and then gets small, as the blade span decreases. Furthermore, the flow condition in the volute is improved thanks to the amelioration of the flows in some blade passages, and the degree of the second flows in the volute is weakened with the application of blade surface slots. Consequently, the flow losses in the volute are reduced effectively.

A Novel Reconstitution Method for Inducing the Formation of Regular 2-Dimensional Arrays of Membrane Proteins and Lipids

1988 ◽  
Vol 46 ◽  
pp. 152-153 ◽  
Author(s):  
A. Engel ◽  
A. Holzenburg ◽  
K. Stauffer ◽  
J. Rosenbusch ◽  
U. Aebi
Keyword(s):  
Membrane Proteins ◽  
Flow Rate ◽  
Lipid Membranes ◽  
Functional Characterization ◽  
Dimensional Structure ◽  
Electron Crystallography ◽  
Peltier Element ◽  
Protein Ratio ◽  
Precise Control ◽  
3 Dimensional

Reconstitution of solubilized and purified membrane proteins in the presence of phospholipids into vesicles allows their functions to be studied by simple bulk measurements (e.g. diffusion of differently sized solutes) or by conductance measurements after transformation into planar membranes. On the other hand, reconstitution into regular protein-lipid arrays, usually forming at a specific lipid-to-protein ratio, provides the basis for determining the 3-dimensional structure of membrane proteins employing the tools of electron crystallography.To refine reconstitution conditions for reproducibly inducing formation of large and highly ordered protein-lipid membranes that are suitable for both electron crystallography and patch clamping experiments aimed at their functional characterization, we built a flow-dialysis device that allows precise control of temperature and flow-rate (Fig. 1). The flow rate is generated by a peristaltic pump and can be adjusted from 1 to 500 ml/h. The dialysis buffer is brought to a preselected temperature during its travel through a meandering path before it enters the dialysis reservoir. A Z-80 based computer controls a Peltier element allowing the temperature profile to be programmed as function of time.

Novel epoxy/anhydride alternatives for biological electron microscopy: Physical and performance characteristis of embed 812 and LX 112 in combination with NSA/NMA/DMAE

1989 ◽  
Vol 47 ◽  
pp. 1000-1001
Author(s):  
Joe A. Mascorro ◽  
Gerald S. Kirby
Keyword(s):  
Electron Microscopy ◽  
Flow Rate ◽  
Succinic Anhydride ◽  
Volume Flow Rate ◽  
Mass Density ◽  
Uranyl Acetate ◽  
Volume Flow ◽  
Base Resin ◽  
And Performance ◽  
Acid Anhydrides

Embedding media based upon an epoxy resin of choice and the acid anhydrides dodecenyl succinic anhydride (DDSA), nadic methyl anhydride (NMA), and catalyzed by the tertiary amine 2,4,6-Tri(dimethylaminomethyl) phenol (DMP-30) are widely used in biological electron microscopy. These media possess a viscosity character that can impair tissue infiltration, particularly if original Epon 812 is utilized as the base resin. Other resins that are considerably less viscous than Epon 812 now are available as replacements. Likewise, nonenyl succinic anhydride (NSA) and dimethylaminoethanol (DMAE) are more fluid than their counterparts DDSA and DMP- 30 commonly used in earlier formulations. This work utilizes novel epoxy and anhydride combinations in order to produce embedding media with desirable flow rate and viscosity parameters that, in turn, would allow the medium to optimally infiltrate tissues. Specifically, embeding media based on EmBed 812 or LX 112 with NSA (in place of DDSA) and DMAE (replacing DMP-30), with NMA remaining constant, are formulated and offered as alternatives for routine biological work.Individual epoxy resins (Table I) or complete embedding media (Tables II-III) were tested for flow rate and viscosity. The novel media were further examined for their ability to infilftrate tissues, polymerize, sectioning and staining character, as well as strength and stability to the electron beam and column vacuum. For physical comparisons, a volume (9 ml) of either resin or media was aspirated into a capillary viscocimeter oriented vertically. The material was then allowed to flow out freely under the influence of gravity and the flow time necessary for the volume to exit was recored (Col B,C; Tables). In addition, the volume flow rate (ml flowing/second; Col D, Tables) was measured. Viscosity (n) could then be determined by using the Hagen-Poiseville relation for laminar flow, n = c.p/Q, where c = a geometric constant from an instrument calibration with water, p = mass density, and Q = volume flow rate. Mass weight and density of the materials were determined as well (Col F,G; Tables). Infiltration schedules utilized were short (1/2 hr 1:1, 3 hrs full resin), intermediate (1/2 hr 1:1, 6 hrs full resin) , or long (1/2 hr 1:1, 6 hrs full resin) in total time. Polymerization schedules ranging from 15 hrs (overnight) through 24, 36, or 48 hrs were tested. Sections demonstrating gold interference colors were collected on unsupported 200- 300 mesh grids and stained sequentially with uranyl acetate and lead citrate.

Severe Drooling and Treatment With Botulinum Toxin

2012 ◽  
Vol 21 (1) ◽  
pp. 15-21
Author(s):  
Merete Bakke ◽  
Allan Bardow ◽  
Eigild Møller
Keyword(s):  
Botulinum Toxin ◽  
Side Effects ◽  
Health Risk ◽  
Flow Rate ◽  
Clinical Evidence ◽  
Acetylcholine Release ◽  
Psychosocial Problems ◽  
Rate Reduction ◽  
Local Inhibition ◽  
Surgical Treatments

Severe drooling is associated with discomfort and psychosocial problems and may constitute a health risk. A variety of different surgical and non-surgical treatments have been used to diminish drooling, some of them with little or uncertain effect and others more effective but irreversible or with side effects. Based on clinical evidence, injection with botulinum toxin (BTX) into the parotid and submandibular glands is a useful treatment option, because it is local, reversible, and with few side effects, although it has to be repeated. The mechanism of BTX is a local inhibition of acetylcholine release, which diminishes receptor-coupled secretion and results in a flow rate reduction of 25–50% for 2–7 months.

EFFECT OF BODY MASS INDEX ON PEAK EXPIRATORY FLOW RATE

2019 ◽  
Vol 3 (9) ◽  
Author(s):  
K. Subramanyam ◽  
Dr. P. Subhash Babu
Keyword(s):  
Body Mass Index ◽  
Body Mass ◽  
Peak Expiratory Flow ◽  
Flow Rate ◽  
Peak Expiratory Flow Rate ◽  
Normal Weight ◽  
The Body ◽  
Health Care Centre ◽  
Expiratory Flow ◽  
Group B

Obesity has become one of the major health issues in India. WHO defines obesity as “A condition with excessive fat accumulation in the body to the extent that the health and wellbeing are adversely affected”. Obesity results from a complex interaction of genetic, behavioral, environmental and socioeconomic factors causing an imbalance in energy production and expenditure. Peak expiratory flow rate is the maximum rate of airflow that can be generated during forced expiratory manoeuvre starting from total lung capacity. The simplicity of the method is its main advantage. It is measured by using a standard Wright Peak Flow Meter or mini Wright Meter. The aim of the study is to see the effect of body mass index on Peak Expiratory Flow Rate values in young adults. The place of a study was done tertiary health care centre, in India for the period of 6 months. Study was performed on 80 subjects age group 20 -30 years, categorised as normal weight BMI =18.5 -24.99 kg/m2 and overweight BMI =25-29.99 kg/m2. There were 40 normal weight BMI (Group A) and 40 over weight BMI (Group B). BMI affects PEFR. Increase in BMI decreases PEFR. Early identification of risk individuals prior to the onset of disease is imperative in our developing country. Keywords: BMI, PEFR.

SCIENTIFIC AND ENGINEERING PRINCIPLES OF EFFICIENT FUEL USE AND ENVIRONMENTALLY FRIENDLY GAS COMBUSTION IN STOVE PLATES. PART 1. MODERN STATE-OF-THE-ART AND DIRECTIONS FOR IMPROVEMENT THE GAS BURNING IN DOMESTIC GAS COOKERS

2017 ◽  
pp. 3-18 ◽  
Author(s):  
B.S. Soroka ◽  
V.V. Horupa
Keyword(s):  
Natural Gas ◽  
Flow Rate ◽  
Gas Flow ◽  
Renewable Energy Sources ◽  
Combustion Process ◽  
Orifice Diameter ◽  
Firing Process ◽  
Gas Flow Rate ◽  
Gas Combustion ◽  
Gas Stoves

Natural gas NG consumption in industry and energy of Ukraine, in recent years falls down as a result of the crisis in the country’s economy, to a certain extent due to the introduction of renewable energy sources along with alternative technologies, while in the utility sector the consumption of fuel gas flow rate enhancing because of an increase the number of consumers. The natural gas is mostly using by domestic purpose for heating of premises and for cooking. These items of the gas utilization in Ukraine are already exceeding the NG consumption in industry. Cooking is proceeding directly in the living quarters, those usually do not meet the requirements of the Ukrainian norms DBN for the ventilation procedures. NG use in household gas stoves is of great importance from the standpoint of controlling the emissions of harmful components of combustion products along with maintenance the satisfactory energy efficiency characteristics of NG using. The main environment pollutants when burning the natural gas in gas stoves are including the nitrogen oxides NOx (to a greater extent — highly toxic NO2 component), carbon oxide CO, formaldehyde CH2O as well as hydrocarbons (unburned UHC and polyaromatic PAH). An overview of environmental documents to control CO and NOx emissions in comparison with the proper norms by USA, EU, Russian Federation, Australia and China, has been completed. The modern designs of the burners for gas stoves are considered along with defining the main characteristics: heat power, the natural gas flow rate, diameter of gas orifice, diameter and spacing the firing openings and other parameters. The modern physical and chemical principles of gas combustion by means of atmospheric ejection burners of gas cookers have been analyzed from the standpoints of combustion process stabilization and of ensuring the stability of flares. Among the factors of the firing process destabilization within the framework of analysis above mentioned, the following forms of unstable combustion/flame unstabilities have been considered: flashback, blow out or flame lifting, and the appearance of flame yellow tips. Bibl. 37, Fig. 11, Tab. 7.

The standard unit mass flow rate of gas-liquid mixtures

2020 ◽  
pp. 13-16
Author(s):  
V.N. Petrov ◽  
◽  
V.F. Sopin ◽  
L.A. Akhmetzyanova ◽  
Ya.S. Petrova ◽  
...  
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Liquid Mixtures ◽  
Unit Mass ◽  
Standard Unit
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