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Emission - Science topic
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Questions related to Emission
Hello,
I am trying to check the status of the optical system in an atomic absorption spectrometer by using it in emission mode.
The model i am working with is a XplorAA Dual (GBC Scientific) system. Currently, we do not have a hollow cathode lamp to test the equipment, but i was told that it could be used in emission mode to check the status of the burner and/or optics before acquiring a HC lamp. The problem is i can't seem to find the information regarding the configuration of the equipment for its use in emission mode. The manual provided doesn't seem to include this information, although i was able to find the configuration option for emission mode in the software.
We also have problems with the installation of the flame shield, it seems some parts are missing or there is something we are not seeing.
GBC Scientific doesn't have an official representative in my country (Argentina) anymore. I have tried to make contact with the technical service in Australia and other Latin american countries to no avail.
If someone familiar with this brand and/or model can help me solve these issues, it would be greatly appreciated.
Best regards,
Dr. Juan Manuel Ostera
Universidad Nacional de Moreno - República Argentina
Exploring the Role of Small Modular Reactors in Achieving Net Zero Emissions for Merchant Vessels by 2050
EDS: energy dispersive spectroscopy
XFS: X-ray Fluorescence spectroscopy
PIXE: proton induced X-ray emission
- I am working on phthalocyanine molecules and recorded photoluminescence absorption and emission in the range 345-700 nm. The compound is in both solid thin film as well as solution form I want to see the non radiative relaxation which proves the mono disperse and aggregated conditions
When Er-doped materials are pumped by 980nm laser, they can emit the light at 1550nm as well as green light due to the energy transfer between different energy level. When all the emission energy come from the pump light, the up-conversion green light should be suppressed in order to maximize the emission energy at 1550nm which is the important for optical amplification at telecommunication wavelength. The question is thus that, how to suppress the up-conversion emission in Er-doped materials and therefore most of the pump energy can be converted into 1550nm?
low R-value is probably related to the higher symmetrical site occupied by Eu3+ ions, supporting the highest emission intensity.
Hello. I am working on ROS production of two systems:
system A is cerium oxide and hydrogen peroxide, system B is cerium oxide nanoparticle, hydrogen peroxide and potassium bromide. I did some antibacterial tests before and the bacteria(e.coli) cultivate in LB broth later mixed with these two systems were killed up to 100%. The results were obtained by plate couting and the plate with system B can kill all E.coli every time, while system A can kill most of them, so I want to go further and investigate the ROS production: singlet oxygen and hydroxyl radical.
singlet oxygen: excitation 488nm, emission 528nm;
hydroxyl radical: excitation 476nm, emission 516nm.
I used a clear-bottom black 96 well plate and add 100ul probe in each well to mix with the systems as below, then incubate them under room temperature for 30 min in dark before using the microplate reader:
system A(CeO2+H2O2)+E.coli
system B(CeO2+H2O2+KBr)+E.coli
system A(CeO2+H2O2)
system B(CeO2+H2O2+KBr)
The result was strange, fluorescence of system A+E.coli sometimes even bigger than system B+E.coli, and the result of system A or B without E.coli addtion were negative values, or bigger than with E.coli addition.
I think there must be some contamination in the process, and I am not familar with all the setting of the microplate reader.
Please help me........
Meadows, D. (1997). Places to Intervene in a System. Whole Earth, 91(1), 78-84.
On P7, it reads:
"In 1986 the US government required that every factory releasing hazardous air pollutants report those emissions publicly. Suddenly everyone could find out precisely what was coming out of the smokestacks in town. There was no law against those emissions, no fines, no determination of "safe" levels, just information. But by 1990 emissions dropped 40 percent. One chemical company that found itself on the Top Ten Polluters list reduced its emissions by 90 percent, just to "get off that list."
This is an exciting story, and I am thinking of using this example to illustrate the effectiveness of information policy instruments in my Environmental Policy course teaching. However, I am wondering, the Clean Air Act was enacted in 1970, and by 1986, there was still no law against emission? No fines? No determination of safe level in the US?
Who can provide a quick answer so that I do not have to dive into the legal documents?
- zero emission
- carbon free
Answering your question on the basis of my research, I conclude that the economic challenges are powerful and are still not fully implemented either with the guidelines of the 2015 Paris Agreement UN Convention, or the demands of the UN COP Climate Conferences, or the guidelines arising from the IPCC Reports, etc. Still the process of transformation of classic social market economies to a green, sustainable, zero-carbon circular economy model is progressing too slowly. There are still high emissions of greenhouse gases, on most continents, in many countries, the predatory logging of forests is being implemented, deforestation instead of aforestation is dominant, still the scale of the level of environmental pollution is high, still the rate of extinction of many species of flora and fauna is proceeding rapidly, still the process of degradation of the biosphere, the destruction of the biodiversity of the planet's natural ecosystems is proceeding rapidly. Meanwhile, the rate of climate warming is accelerating. In the current 2024, the global average atmospheric temp. has increased by 1.5 degrees C relative to the state at the beginning of the first industrial revolution, and in Europe this has even already seen an increase in atmospheric temp. over this period of time of about 2.5 degrees C. Therefore, the economic challenges are enormous and are still under-implemented. Unfortunately, the process of green transformation of the economy, including the green transformation of the energy sector and other sectors of the economy in many countries is progressing too slowly. At the rate at which this process has been implemented in recent years, the achievement of the state of a global zero-carbon, sustainable, green closed-loop economy by 2050 is highly doubtful and even more so there is a high risk of failing to halt the process of global warming, as there are only a few years left to reach the tipping point of civilization's amount of CO2, methane and other greenhouse gases accumulated in the planet's atmosphere, after which the process of global warming will be completely out of control, become irreversible and further accelerate significantly. I have written more on this subject in the following publication.
I am conducting research on this issue. I have included the conclusions of my research in the following article:
IMPLEMENTATION OF THE PRINCIPLES OF SUSTAINABLE ECONOMY DEVELOPMENT AS A KEY ELEMENT OF THE PRO-ECOLOGICAL TRANSFORMATION OF THE ECONOMY TOWARDS GREEN ECONOMY AND CIRCULAR ECONOMY
I invite you to learn more about the issues described in the article given above and to cooperate with me in scientific research on these issues.
Please write what you think in this problematic?
What is your opinion on this issue?
I invite you to scientific cooperation in this problematic.
My warmest greetings,
Dariusz Prokopowicz
The above text is entirely my own work written by me on the basis of my research.
In writing this text I did not use other sources or automatic text generation systems.
Copyright by Dariusz Prokopowicz
Hi,
I have a question about emission factors for passenger cars based on the EMEP/EEA air pollutant emission inventory guidebook 2023, in the link that I used to calculate the CO2 emission per vehicle per household for a dataset of 2016- 2017: https://efdb.apps.eea.europa.eu/?source=%7B%22query%22%3A%7B%22bool%22%3A%7B%22must%22%3A%5B%7B%22term%22%3A%7B%22code%22%3A%221.A.3.b.i%20Road%20transport%2C%20passenger%20cars%22%7D%7D%2C%7B%22term%22%3A%7B%22Fuel%22%3A%22Petrol%22%7D%7D%2C%7B%22term%22%3A%7B%22Pollutant%22%3A%22CO2%22%7D%7D%2C%7B%22term%22%3A%7B%22Type%22%3A%22Tier%202%20Emission%20Factor%22%7D%7D%5D%7D%7D%2C%22display_type%22%3A%22tabular%22%7D
the emission factors are like 0.398 g/km much smaller than the 118.1 gram/km in 2016 based on the: https://www.eea.europa.eu/en/analysis/indicators/co2-performance-of-new-passenger
so, my average CO2 emission from private cars in the dataset is much lower than expected, suppose that the emission factor of 118.1 g/km, and an average km driven of around 13000km the CO2 is is 1,535,300 g/km and my average is about 173 g/km so this is a factor 10 different
could you please explain these two different emission factors? i mean the 0.398 g/km and the 118.1 g/km?
Do we have to use kg N or kg organic fertilizer multiply by emission factor of organic fertilizer production?
Organic fertilizers are made from natural materials and are generally considered to have a lower carbon footprint than mineral fertilizers. To calculate the exact carbon footprint, the origin and production methods of each raw material should be known. Organic fertilizers can vary depending on their production method, transportation distance and the type of organic materials used. Also, animal manure and meals are known to have a higher carbon footprint compared to vegetal raw materials due to the release of greenhouse gases such as methane and nitrous oxide, which are more potent than carbon dioxide. Manure compost accounted for 5 % of the total CO2 emissions, while residual roots and root exudates contributed 2 % and 57 %, respectively, suggesting a higher labile carbon content in root exudates. The remaining 36 % of CO2 emissions was derived from the soil and other sources. CO2 emission factors are 6 % for manure compost, 12 % for roots, and 2 % for root exudates. By quantifying the direct emissions from manure compost, residual roots, root exudates, and soil, The calculated carbon footprints were 0.8 kgCO2,eq./kg for N
Could anyone suggest me what is effect of electron donating and withdrawing group on fluorecence emission or intersystem crosssing.
Thank you
I am studying the interaction between carbon dots and fluorescent organic dyes like Rhodamine 6G, which have an overlap between the emission of the CDs and absorption of the dyes.
In spectroscopic analysis, as I increase the concentration of the dyes in the CDs solution, the emission peak quenches, while the fluorescence lifetime increases as the concentration of the dye increases. Additionally, the emission intensities of the dyes increase. In a typical FRET (Förster Resonance Energy Transfer) process, the emission of the carbon dots is expected to decrease, and the emission of the dye is expected to increase. This is happening with my samples, but the fluorescence lifetime of the CDs is expected to decrease. However, in my CDs sample, the lifetime increases as I increase the amount of the quenching dyes.
Can you please share suggestions to understand this anomalous observation?.
Hello Everyone,
I have done UV-Vis absorbance and PL emission of 3 samples. When plotted, there is a clear correlation between UV-Vis absorption and PL emission spectrums, where the sample with the highest absorbance possesses the lowest excitonic emission. Is there any reason behind it, or is it just a coincidence? Or should I repeat the measurements?
I appreciate your time. Thanks.
Thermal emission is temperature dependent. Non-thermal emission is not temperature dependent such as synchrotron emission.
In order to proceed with the quantification of an Azide Alkyne Cycloaddition reaction efficiency by using a fluorogenic probe with Cy5-DBCO, I first need to construct a calibration curve. The problem is that water gives me fluorescence intensity values as well at an excitation wavelength of 647 nm and emission of 668 nm (excitation and emission that correspond to Cy5). I observe this using just water as a background control and it shows really high values. I am using a TECAN infinite 200 instrument and the samples are prepared in a black polystyrene 96-well plate.
I wasn't paying attention to your dye. Here are the spectra for Cy 5 to give you an idea what wavelengths you can use. The ones you chose are the most intense, but not well suited for your instrument.
I performed calculation using Gaussian to obtain the fluorescence emission of some organic molecules. The following lines are the data of the optimized singlet state geometry. why does the first excited state has lower wavelength emission than the second excited state ?
Excited State 1: Singlet-A 1.9113 eV 648.69 nm f=0.0008 <S**2>=0.000
85 -> 89 -0.69679
This state for optimization and/or second-order correction.
Total Energy, E(TD-HF/TD-KS) = -1179.74328545
Copying the excited state density for this state as the 1-particle RhoCI density.
Excited State 2: Singlet-A 1.3773 eV 900.19 nm f=0.4216 <S**2>=0.000
88 -> 89 0.70630
Dear Researchers,
I have 100+ existing inland ships' hull lines plans along with their operational data like service speed, capacity, fuel consumption, main engine power, MCR at service condition, etc. I would like to start a research work focusing the reduction of fuel consumption and emission. Any other innovative research idea is also most welcome.
If anyone one shows interest for joint research, please send msg.
Thanks and best regards
Dr S M Rashidul Hasan
Earth’s Carbon cycle and Temperature
Slow Carbon Cycle:
Carbon takes around 100 – 200 million years to move through
rocks, soil, ocean and atmosphere.
10 - 100 million metric tons of carbon move through
Slow Carbon cycle per annum.
10,000 – 1,00,000 million metric tons of carbon move through
Fast Carbon cycle per annum.
Earth naturally absorbs (by oceans and forests) and
emits (undersea volcanos and hydrothermal vents)
around 100 billion metric tons of carbon per annum
(roughly equivalent to 400 billion tons of CO2).
CO2 Emissions from fossil fuels in 2023: Roughly 40 billion metric tons.
Ratio: CO2 Emissions from fossil fuels amounts to just 10% of natural CO2 emission and absorption by earth.
Moral
Overall carbon cycle, over a very long term,
is expected to maintain a balance,
which keeps earth’s temperature
to remain to be relatively stable.
However, over a relatively shorter time period,
earth fluctuates between ice ages and warmer interglacial periods,
where, parts of carbon cycle may even intensify
the short-term temperature changes
(which, we keep experiencing now),
and thereby significantly affecting
the stability of earth’s temperature.
Nature will take care
the balance of
carbon-cycle
as well as
temperature
on its own,
but very slowly.
Leaving aside
altering earth's climate,
Have we understood
the nature
(including the 'coupled' effect of
Milankovitch theory: eccentricity/obliquity/precession;
cirrus clouds effect;
albedo effect;
urban island effect;
El Nino effect)
in a single (human) life span?
Even, if it is so,
whether,
all the fundamental laws
remain valid
for such a complex system?
Even, if smarter one
manages to convince
that the earth's climate system
be modelled precisely,
how will the model results
be validated (in the absence of any future data)??
If not, how do we forecast?
[Only recent temperature data remains to be
satellite based,
while we used thermometers
(which just measures the degrees of hotness)
earlier.
Before 1624??]
Do we have
a well-defined
'Conceptual Model'
and its respective
'Mathematical Model'
(assuming that
we have a super computer
for numerical model)
that forecasts
how exactly climate change
will affect
extreme precipitation events
and sea levels?
Which conceptualization
has led to the prediction that
CO2 emissions from fossil fuels,
particularly from oil & gas industries
have led to the rise
in mean global temperature?
Is there any specific
spatial and temporal scales
over which
these climate models work?
With 428 ppm as on date,
feasible to distinguish
the CO2 emissions
from various sources?
Suresh Kumar Govindarajan
in the synchronous fluorescence measurements, the difference between excitation and emission wavelengths (Δλ) was fixed at 60 nm or 50 nm for Trp or 20 nm/ 15 nm for Tyr residues?
please answer which is the right Δλ for both Trp and Tyr? and Why?
Hello for everyone, I come to you to help me find a solution to my problem in the GC MSD.I reinstalled the external filaments but it does not work normally and an error message is displayed “The filament shows emission current while the filament is off” could you guide me to find a solution to this problem please.
We have grown boron nitride with a monolayer thickness. XRD usually is used to understand the polymorphism of any material. However, due to the minimum thickness of the sample, it won't work for our investigation.
PL is another choice, and a few papers have also demonstrated near-band edge emission to explain polymorphism. However, our research is focused on sub-bandgap emissions.
Which experimental tool can help us to understand the polymorphism of BN?
Hi all,
I'm working on calculations related to electron-phonon interactions during thermionic emission in a 2D material, using ab initio methods. I've come across the electron-phonon coupling constant, a dimensionless parameter commonly used in deriving the superconducting transition temperature. I'm curious about how this parameter can be related to thermal electron emission.
I can calculate the Density of States for my material and I have the Fermi-Dirac distribution at the emission temperature. I'm considering that incorporating the electron-phonon coupling constant might allow me to calculate a term for the emission probability, which could then yield the thermionic emission rate but I don't know the term. Could anyone assist me with this approach? Your help would be greatly appreciated
I have a fluorophore and its emission is quenched on adding analyte compound. The overlapping spectra of compound and analyte make UV-vis absorption analysis unreliable.
The analyte mixture spectra shows larger absorbance value than fluorophore compound.
Although I depend on emission spectroscopy for the quenching constants and etc.
I'm curious to know if there are any possible computing methods to overcome this problem and making the absorption spectrums useful for my purpose (explaining emission quenching)?
THE FATE OF “SOURCE-INDEPENDENCE” IN ELECTROMAGNETISM, GRAVITATION, AND MONOPOLES
Raphael Neelamkavil, Ph.D., Dr. phil.
With the introductory claim that I make here suggestions that seem rationally acceptable in physics and the philosophy of physics, I attempt here to connect reasons beyond the concepts of magnetic monopoles, electromagnetic propagation, and gravitation.
A magnetic or other monopole is conceptually built to be such only insofar as the basic consideration with respect to it is that of the high speed and the direction of movement of propagation of the so-called monopole. Let me attempt to substantiate this claim accommodating also the theories in which the so-called magnetic monopole’s velocity could be sub-luminal.
If its velocity is sub-luminal, its source-dependence may be demonstrated, without difficulty, directly from the fact that the velocity of the gross source affects the velocity of the sub-luminal material propagations from it. This is clear from the fact that some causal change in the gross source is what has initiated the emission of the sub-luminal matter propagation, and hence the emission is affected by the velocity of the source’s part which has initiated the emission.
But the same is the case also with energy emissions and the subsequent propagation of luminal-velocity wavicles, because (1) some change in exactly one physical sub-state of the gross source (i.e., exactly the sub-state part of the gross source in which the emission takes place) has initiated the emission of the energy wavicle, (2) the change within the sub-state part in the gross source must surely have been affected also by the velocity of the gross source and the specific velocity of the sub-state part, and (3) there will surely be involved in the sub-state part at least some external agitations, however minute, which are not taken into consideration, not possible to consider, and are pragmatically not necessary to be taken into consideration.
Some might claim (1) that even electromagnetic and gravitational propagations are just mathematical waves without corporeality (because they are mathematically considered as absolute, infinitesimally thin waves and/or infinitesimal particles) or (2) that they are mere existent monopole objects conducted in luminal velocity but without an opposite pole and with nothing specifically existent between the two poles. How can an object have only a single part, which they term mathematically as the only pole?
The mathematical necessity to name it a monopole shows that the level of velocity of the wavicle is such that (1) its conventionally accepted criterial nature to measure all other motions makes it only conceptually insuperable and hence comparable in theoretical effects to the infinity-/zero-limit of the amount of matter, energy, etc. in the universe, and that (2) this should help terming the wavicle (a) as infinitesimally elongated or concentrated and hence as a physically non-existent wave-shaped or particle-shaped carrier of energy or (b) as an existent monopole with nothing except the one mathematically described pole in existence.
If a wavicle or a monopole is existent, it should have parts in all the three spatial directions, however great and seemingly insuperable its velocity may be when mathematically tested in terms of its own velocity as initiated by STR and GTR and later accepted by all physical sciences. If anyone prefers to call the above arguments as a nonsensical commonsense, I should accept it with a smile. In any case, I would continue to insist that physicists want to describe only existent objects / processes, and not non-existent stuff.
The part A at the initial moment of issue of the wavicle represents the phase of emission of the energy wavicle, and it surely has an effect on the source, because at least a quantum of energy is lost from the source and hence, as a result of the emission of the quantum, (1) certain changes have taken place in the source and (2) certain changes have taken place also in the emitted quantum. This fact is also the foundation of the Uncertainty Principle of Heisenberg. How then can the energy propagation be source-independent?
Source-independence with respect to the sub-luminal level of velocity of the source is defined with respect to the speed of energy propagation merely in a conventional manner. And then how can we demand that, since our definition of sub-luminal motions is with respect to our observation with respect to the luminal speed, all material objects should move sub-luminally?
This is the conventionally chosen effect that allegedly frees the wavicle from the effect of the velocity of the source. If physics must not respect this convention as a necessary postulate in STR and GTR and hence also in QM, energy emission must necessarily be source-dependent, because at least a quantum of energy is lost from the source and hence (1) certain changes have taken place in the source, and (2) certain changes have taken place also in the emitted quantum.
(I invite critical evaluations from earnest scientists and thinkers.)
I am using a fluorescence microscope with DAPI filter, here are the specifications:
Excitation wavelength: 360/40 nm
Emission wavelength: 460/50 nm
Dichroic mirror wavelength: 400 nm
I want to label my cells with cyan fluorescent protein. I just want to know if our DAPI filter can detect the CFP. Thanks.
Through my preliminary experiments, it was found that there is an emission of abnormal ultra-high energy electrons downstream of the RF cavity of the electron storage ring, which I theoretically predicted. Therefore, I call on particle physicists to conduct more experiments to fully verify this previously unknown phenomenon with important significance.
can anyone give me advise about charge transfer transition of transition metal and rare earth element?
and usually people see the FL and absorption, emission spectra of those materials in glass, and I just want to know how much energy need to ionization the transition metal and rare earth element.
Could you recommend some studying source about it?
As the article reported,
Reaction Yield= mpurified*w%/n*MPb
where mpurified is the mass of the dried quantum dots, w% is the mass
percentage of lead (28.74 %) [by inductively coupled plasma optical
emission spectroscopy (ICP-OES) elemental analysis], n is the number of
CsPbBr3 quantum dot moles, and MPb is 207.
n should be the moles of Pb precursor according to "The reaction yield is assessed in terms of Pb present in the DBSA-QDs compared to the Pb precursor."
What is the Relationship Between Vacuum and Space?
The historical evolution of the concept of "vacuum" [1] can be roughly described as the following.
0) Buddhist Vacuum: the void formlessness, the empty barrier-free. It refers to the place and space where all dharmas exist. There are four meanings: pervasive, immovable, endless, and eternal.
I) Conceptual Vacuum: Aristotle in ancient Greek era believed that " Void separated from the matter does not exist" [2], the void must be filled with matter in order to be able to carry out physical action*. The concept of vacuum at this stage is void, a state of space.
II) Industrial vacuum: Evangelista Torricelli (1608-1647), secretary and assistant of Galileo Galilei (1564-1642), proved the "vacuum" without an atmosphere using a mercury barometer [3]. The concept of vacuum at this stage was static and overlapped with Newton's absolute space.
III) Ether Vacuum: “......, as the recipient of energy, is to regard it as continuously filling all space, and possessing the mobility of fluid rather than the rigidity of a solid. If whatever possess the property of inertia be matter, then the medium is a form of matter. But away from ordinary matter it is, for obvious reasons, best to call it as usual by a separate name, the ether."[4] "The aether is the solitary tenant of the universe, save for that infinitesimal fraction of space which is occupied by ordinary matter."[5]. The vacuum at this stage is the medium through which electromagnetic waves can travel.
IV) Quantum Vacuum: Along with the development of quantum mechanics, numerous vacuum-related concepts have arisen, the ground state, the various excited states, zero point energy, negative energy sea, spontaneous emission, Vacuum polarization, vacuum fluctuations, etc.. "The vacuum is, in fact, precisely the ground state of the fundamental many-field system. "[9]† "In a quantum theory, the vacuum is a very busy place. Particle-antiparticle pairs are constantly produced out of nothing, violating the energy-conservation law by borrowing an amount of energy E from the vacuum for a time t such that Et<ℏ, according to Heisenberg's uncertainty principle. "As the Higgs boson propagates in the quantum vacuum, it feels the presence of virtual particles and interacts with them."[6] and theoretically and experimentally identified the Casimir effect for verifying vacuum energy[7][8], and the Lamb shift. The concept of vacuum at this stage provides a self-consistent ground for quantum field theory, where the vacuum is seen as a separate background for spacetime.
V) Relativity Vacuum： Quantum field theory predicts that a uniformly accelerated particle detector sees the vacuum as a thermal bath with temperature T related to its proper acceleration a, i.e., T =a/2π, as a result of the interaction between the detector and the fluctuating vacuum scalar fields, and this is called the Fulling-Davies-Unruh (FDU) effect. Vacuum and space appear to be separate.
VI) Planck Scales Vacuum: Some of the new physics considers the vacuum to be more complex, with the emergence of Quantum foams [11], Spin foams, Quantum spacetime [12], String Network, Lattice structure, Conformal structure [13], and other concepts [14]. Space is discretized and the Vacuum seems to merge with Space again.
VII) Dark Energy Vacuum: It is believed by some people that the vacuum energy is dark energy, and therefore the vacuum is a place with a certain dark energy density. In this case, the vacuum has the effect of the cosmological constant Λ [15], which is the driving force for the accelerated expansion of space-time.
It appears that the relationship between the various vacuums and space is not consistent. Without a clear definition on this most fundamental issue of physics, it may already be a potential obstacle to progress.
Our questions are:
1) Is the size of the vacuum the same as the size of cosmic space? When cosmic space inflation or expands, is the cosmic vacuum also inflating or expanding?
2) If the vacuum is not empty, is it uniform? Is it affected by the General Relativity Space-Time Metric (Curvature)? Is the vacuum inside a black hole the same as the vacuum elsewhere?
3) In a particle accelerator, does an electron traveling at high speed see the same vacuum as a stationary electron? Do electrons interact with the vacuum only at the moment of collision?
4) Without vacuum energy, is there no possibility of producing any particles in space? How were the initial elementary particles excited‡?
5) Would our conception of the vacuum change if we gave up the dynamical function of the uncertainty principle?
--------------------
Notes
* Aristotle gives an example, if a ball is thrown up, and it continues to fly after it has been released from the hand, it means that something must be holding it up one after the other, otherwise it would have fallen down. Note that this plain view is not necessarily wrong. Without borrowing the notion of conservation of energy-momentum, our explanation must return to the plain description. In fact, the intuitive interpretation of conservation of energy-momentum itself still requires this plain view.
‡ "What relation subsists between the medium which fills the interstellar void and the condensations of matter that are scattered throughout it?"[5] The relation between vacuum energy and visible energy was questioned 100 years ago.
† In the literature [9] the vacuum is specified, the Higgs vacuum, electromagnetic field vacuum, Dirac electron vacuum, the boson vacuum, the QCD vacuum......
--------------------
References
[1] 张天蓉. (2022). 真空. https://blog.sciencenet.cn/blog-677221-1342155.html
[2] Aristotle. (1929). The Metaphysics [物理学] (张竹明, Trans.).
[4] Heaviside, O. (1892). On the forces, stresses, and fluxes of energy in the electromagnetic field. Philosophical Transactions of the Royal Society of London.(A.)(183), 423-480.
[5] Whittaker, E. (1910). A History of the Theories of Aether and Electricity (Vol. Vol. I: The Classical Theories; Vol. II: The Modern Theories, 1900-1926). Courier Dover Publications（1989）极好的早期物理学历史著作。
[6] Kane, G., & Pierce, A. (2008). Perspectives on LHC physics. World Scientific Publishing Co. Pte. Ltd.
[7] Casimir, H. B. (1948). On the attraction between two perfectly conducting plates. Proc. Kon. Ned. Akad. Wet.,
[8] Jaffe, R. L. (2005). Casimir effect and the quantum vacuum. Physical Review D, 72(2), 021301. https://doi.org/10.1103/PhysRevD.72.021301
[9] Aitchison, I. J. R. (1985). Nothing's plenty the vacuum in modern quantum field theory. Contemporary Physics, 26(4), 333-391. https://doi.org/10.1080/00107518508219107
[10] Zhou, W., & Yu, H. (2020). Collective transitions of two entangled atoms and the Fulling-Davies-Unruh effect. Physical Review D, 101(8), 085009.
[11] Misner, C. W., Thorne, K. S., & Zurek, W. H. (2009). John Wheeler, relativity, and quantum information. Physics Today, 62(4), 40-46.
[12] Ashtekar, A., & Singh, P. (2011). Loop quantum cosmology: a status report. Classical and quantum gravity, 28(21), 213001.
Rovelli, C. (2008). Loop Quantum Gravity. Living Reviews in Relativity, 11(1), 5. https://doi.org/10.12942/lrr-2008-5
[13] Penrose, R. (2012). The basic ideas of conformal cyclic cosmology. AIP Conference Proceedings 11,
[14] Addazi, A., Alvarez-Muniz, J., & etl. (2022). Quantum gravity phenomenology at the dawn of the multi-messenger era—A review. Progress in Particle and Nuclear Physics, 125, 103948. https://doi.org/https://doi.org/10.1016/j.ppnp.2022.103948
[15] Peebles, P. J. E., & Ratra, B. (2003). The cosmological constant and dark energy. Reviews of Modern Physics, 75(2), 559.
Hi there. Can DAPI be excited with 440 nm wavelength? Maybe still a bit of tail is there from the absorption spectrum, yet we are much in the emission spectrum already. Making me think what we get is mainly just stimulated emission. Anyone has experience on a similar test?
I have emission and sink of CO2 from 2060 to 2015 and I use a box model for the troposphere or world to predict a future scenario in excel and SPSS. I also need to make different scenarios I guess on I assumptions, so would you please enlighten me about how to do that? Many thanks.
Looking for thoughts:
(i) How to verify Methodology of GHG Emission for Armed Conflict, considering no clear methodology identified by UNFCC, nor academia use consistent factors as baseline for calculation?
(ii) Why some studies consider emission for destruction of concrete building in addition to reconstruction, while other only consider rebuilding? Is it the significant amount of concrete and release of of CO2 due destruction?
Is there any open-access source where I can find the emission factors for the Scope 3 components of an educational institution?
The components include:
chemical,
glassware,
capital goods,
computer accessories,
electronics and electrical products,
commuting and business travels,
refrigerants,
consumed water
transport
wastes
Is there any weather data morphing tool (for hourly weather data) to predict climate change for future using the IPCC AR5 (assessment report 5) emission scenarios I.e. rcp 2.5, rcp 4.5, rcp 6 & rcp 8?
It should be noted that the synthesized particle has a blue emission
A company produces PP surgical products from granular raw materials by injection. molding technique. They did not find any weight loss after melting. According to the manufacturer policies, they should mention the amount of CO2 emission. How do they measure the amount of CO2 emission?
I am considering planck's equation where Intensity of emission is a function of wavelength and temperature . If we have the intensity value for a particular wavelength (determined through emission spectroscopy) for solid propellant combustion case. Then in planck's equation for grey body emissivity and temperature will be the two unknowns.
As an end result I want to determine temperature in the solid propellant combustion flame by knowing intensity of the emission emitted at a particular wavelength. But since the hot particles which are emitting that intensity in the flame are like grey bodies emissivity has to be known to find out temperature of the hot particles (grey body).
Please help me in determining the emissivity so that temperature can be determined from intensity and wavelength data. Please refer equations given in section 3.2 (Continuous Spectra) of the attached reference paper.
The triplet energy stands as a crucial factor in adjusting the emission of TADF compounds. Discovering how to measure and calculate it using simple techniques is essential.
I understand that ED-XRF or WD-XRF only allows for high energy photon emission. I am wondering if it is possible to obtain emission in the visible region by attaching an external optical fiber to a spectrophotometer (Ocean Optics)? However, I am skeptical about this since the chambers used for XRF are typically sealed. Do you have any other suggestions?
Thanks for your response Gerhard Martens . I got a nice paper . Just to summarize-
(a) I need to have a clinical x-ray source and need to focus this on the sample kept inside an integrated sphere.
(b) a spectrometer will be connected with an optical fibre to get the desired spectra.
It is better to cover the set up under Pb chamber.
I characterized my materials by PL spectroscopy. I observed some enhancement in my emission intensity. From this data can I calculate Quantum yield? If anybody know the calculation please give the notes.
Hello. I have vehicle specific power (VSP) values I calculated from different speeds and gradients (uphill and downhill), always considering zero acceleration. With these binned VSP values, I have the corresponding CO2 emissions in g/s that I got from the EPA's "Methodology for Developing Modal Emission Rates for EPA’s Multi-Scale Motor
Vehicle and Equipment Emission System", but I would rather have them in g/km.
I'm messing something up, because I have emissions for a downhill slope (<=-2,5%) at 10km/h of 537,66 g/km and for an uphill slope (>2,5%) and speed 120km/h of 214,95g/km.
This makes no sense to me.
What I did to convert the values was consider that, e.g., for an emission of 1,5g CO2/s, and for a speed of 10 km/h (or 2,78m/s), was:
1,5g/s : 2,78m/s = 0,54g/m. So, for a total distance of 1km: 0,54 * 1000 = 540 g/km.
Is this reasoning correct? I'm going absolutely mad with this! Would appreciate any help.
Thank you
Global warming potential is calculated from the sum of CO2-equivalents from N2O and CH4 emissions. Why is carbon dioxide emission NOT included in global warming potential?
GWP (kg CO2 equivalent ha ) = CH4 (kg CH4 ha-1 ) X 28 + N2O (kg N2O ha ) X 265.
CH4 emission is greater 28 times and N2O is 265 times greater than CO2 emission in greenhouse potential, nevertheless total CO2 emission is much greater than CH4 or N2O.
Greeting Researchers
What is the accepted level of CO and NOx gas emission to the atmosphere ????
To whom it may concern,
Does anyone could explain me what is the components of the alpha emission quantity unit : Cph/cm² ?
C is for Coulomn ? ph ? I don't really understand...
Thanks in advance,
Vincent
The study object is a flat diode.
In the Particle Tracking solver, in the emission model settings (Edit Particle Area Source – Tracking emission model – Emission Settings) for Space Charge Limited Emission, Thermionic Emission, there is a Kinetic Settings tab (Fig. 1).
1) If temperature is selected as the kinetic characteristic (for Uniform distribution - Kinetic type: Temperature, for Maxwell distribution - Temperature), then what value should be set, the cathode temperature?
2) Velocity is selected as the kinetic characteristic (for Uniform distribution - Kinetic type: Velocity). The dependence of the emission current on the velocity I(v) is obtained. The emission current decreased with increasing speed (Fig. 2).
Energy is chosen as the kinetic characteristic (for Uniform distribution - Kinetic type: Energy). The dependence of the emission current on the energy I(U) is obtained. The emission current increased with increasing energy (Fig. 3).
How to understand the opposite behavior of the dependencies under consideration if energy and velocity are directly related: U= mv^2/(2*e)?
3) In the Thermionic Emission model settings, the temperature appears in both General and Kinetic Settings (Fig. 4). The temperature value in both General and Kinetic Settings should be the same?
Carbon storage potential of the floral species exhibits significant spatial variation depending on the near-surface atmospheric CO2 level that regulates the leaf thickness.
Definitely...... We made a comprehensive study on this and published two important reports with the case study of Plantation by power sectors
I want to know how to measure methane emissions in dairy animals at the field level along with what kind of data to be measured .......
both are about excitation , is there same?
Interferences in plasma spectral analysis can certainly occur and can pose challenges when conducting analytical tests. The accuracy and dependability of the results can be seriously impacted by interference in elemental analysis. Plasma spectral analysis, often performed using techniques like inductively coupled plasma-mass spectrometry (ICP-MS) or inductively coupled plasma optical emission spectrometry (ICP-OES), is highly sensitive and capable of detecting trace elements and ions. One of the common types of interference is the Spectral interference. This phenomenon takes place when the analyte's emission or absorption lines and the lines of other elements in the sample cross each other. As a result, the target analyte may not be quantified correctly.
References:
Rosen, V. (2023, July 16). Interferences in ICP-OES/MS: Linkedin. https://www.linkedin.com/pulse/41-note-interferences-icp-oesms-vasiliy-v-rosen-ph-d-?trk=pulse-article
Thermo Fisher Scientific. (2021, September 16). Interferences Explained, ICP-OES Part 1. https://www.spectroscopyonline.com/view/interferences-explained-icp-oes-part-1
Can you briefly calculate carbon dioxide or greenhouse gas emissions from heating loads?
Example: 10 kwh/㎡·a * CO2 emission coefficient (kg/kwh) = ⅹ(kg/kwh·a)
If the transition is instantaneous, the moment the photon appears must be superluminal.
In quantum mechanics, Bohr's semi-classical model, Heisenberg's matrix mechanics, and Schödinger's wave function are all able to support the assumption of energy levels of atoms and coincide with the spectra of atoms. It is the operating mode of most light sources, including lasers. This shows that the body of their theories is all correct. If they are merged into one theory describing the structure image, it must have the characteristics of all three at the same time. Bohr's ∨ Heisenberg's ∨ Schödinger's, will form the final atomic theory*.
The jump of an electron in an atom, whether absorbed or radiated, is in the form of a single photon, and taking the smallest energy unit. For the same energy difference ΔE, jumping chooses a single photon over multiple photons with lower frequency ν, suggesting that a single photon structure has a more reasonable match between atomic orbital structures**.
ΔE=hν ......(1)
ΔE=Em-En ......(2)
It is clear that without information about Em, En at the same time, generating a definite jump frequency ν is impossible. "Rutherford pointed out that Rutherford pointed out that if, as Bohr did, one postulates that the frequency of light ν, which an electron emits in a transition, depends on the difference between the initial energy level and the final energy level, it appears as if the electron must "know" the frequency of light ν. level and the final energy level, it appears as if the electron must "know" to what final energy level it is heading in order to emit light with the right frequency."[1].
Bohr's postulate of Eq. (1)(2) energy level difference is valid [2]. But it does not hold as axiomatic postulate. This is not just because all possible reasons have not been ruled out. For example, one of the most important reasons is that the relationship between the "wave structure" of the electron and the electromagnetic field has not been determined†. Only if this direct relationship is established can the transition process between them be described. It is also required that the wave function and the electromagnetic field are not independent things, and it is required that the wave function is a continuous field distribution, not a probability distribution [5]. More importantly, Eqs. (1)(2) do not fulfill the axiomatic condition of being axiomatic postulate, which is not capable of ignoring the null information‡.
Doing it as a comparison of questions is the same as when we ask how the photon controls its speed [3] and where the photon should reach next. They are both photon behaviors that must rest on a common ground.
Considering the electron transition as a source of light, it is equally consistent with the principle of Special Relativity, and the photons radiated must be at the speed of light c and independent of the speed of the electrons††. However, if the light-emitting process is not continuous, the phenomenon of superluminal speed occurs.
We decompose the light-emitting process into two stages. The first stage, from "nothing" to "something", is the transition stage; the second stage, from something to propagation, is the normal state. According to classical physics, if the light emission is instantaneous, i.e., it does not occupy time and space. Then we can infer that the photon from nothing to something is not a continuous process, but an infinite process, and the speed at which the photon is produced is infinity. We cannot believe that the speed of propagation of light is finite and the speed at which light is produced is infinite. There is no way to bridge from the infinite to the finite, and we believe that this also violates the principle of the constancy of the speed of light.
There is no other choice for the way to solve this problem. The first is to recognize that all light emitting is a transitional "process" that occupies the same time and space, and that this transitional process must also be at the speed of light, regardless of the speed of the source of light (and we consider all forms of light emitting to be sources of light). This is guaranteed by and only by the theory of relativity. SR will match the spacetime measure to the speed of light at any light source speed. Secondly, photons cannot occur in a probabilistic manner, since probability implies independence from spacetime and remains an infinity problem. Third, photons cannot be treated as point particles in this scenario. That is, the photon must be spatially scaled, otherwise the transition process cannot be established. Fourth, in order to establish a continuous process of light emission, the "source" of photons, whether it is an accelerated electron, or the "wave function" of the electron jump, or the positive and negative electron annihilation, are required to be able to, with the help of space and time, continuous transition to photons. This will force us to think about what the wave function is.
Thinking carefully about this question, maybe we can get a sense of the nature of everything, of the extensive and indispensable role of time and space.
Our questions are:
1) Regardless of the solution belonging to which theory, where did the electron get the information about the jump target? Does this mean that the wave function of the electron should span all "orbitals" of the atom at the same time.
2) If the jump is a non-time-consuming process, should it be considered a superluminal phenomenon¶ [4]?
3) If the jump is a non-time consuming process, does it conflict with the Uncertainty Principle [5]?
4) What relationship should the wave function have to the photon to ensure that it produces the right photon?
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Notes:
* Even the theory of the atomic nucleus. After all, when the nucleus is considered as a "black box", it presents only electromagnetic and gravitational fields.
* * It also limits the possibility that the photon is a mixed-wavelength structure. "Bohr noticed that a wave packet of limited extension in space and time can only be built up by the superposition of a number of elementary waves with a large range of wave numbers and frequencies [2].
† For example, there is a direct relationship between the "electron cloud" expressed by the wave function of the hydrogen steady state, and the radiating photons. With this direct relationship, it is possible to determine the frequency information between the transition energy levels.
‡ If a theory considers information as the most fundamental constituent, then it has to be able to answer the questions involved here.
†† Why and how to achieve independence from the speed of light cannot be divorced from SR by its very nature, but additional definitions are needed. See separate topic.
¶ These questions would relate to the questions posed in [3][4][5].
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References:
[1] Faye, J. (2019). "Copenhagen Interpretation of Quantum Mechanics." The Stanford Encyclopedia of Philosophy from <https://plato.stanford.edu/archives/win2019/entries/qm-copenhagen/>.
[2] Bohr, N., H. A. Kramers and J. C. Slater (1924). "LXXVI. The quantum theory of radiation." The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science 47(281): 785-802. This was an important paper known as "BSK"; the principle of conservation of energy-momentum was abandoned, and only conservation of energy-momentum in the statistical sense was recognized.
[3] “How does light know its speed?”；
[4] “Should all light-emitting processes be described by the same equations?”；
[5] “Does Born's statistical interpretation of the wave function conflict with ‘the Uncertainty Principle’?” https://www.researchgate.net/post/NO13_Does_Borns_statistical_interpretation_of_the_wave_function_conflict_with_the_Uncertainty_Principle；
When we measure the photoluminescence (PL) emission of some nanoparticles we find sometimes emission bands at energy higher than the optical bandgap. It is normal to observe photoluminescence at energies below the material bandgap as a result to the presence of localized defect states. However PL at energies higher than the optical bandgap it look strange!
Hello research community,
I got CFD simulation results of an internal combustion engine regarding emission in kg unit. For example: 14.5 gram of CO per cycle.
I need to convert this number to g/kW-hr to compare it with standards.
Anyone has any ideas?
In dumping operation of hot wet materials, for example, there is emission of particulate matter together with water vapor, which difficult the measurement of opacity. Is there any way to solve this problem, or other techniques to quantify the PM?
How does stokes shift of nitrogen-doped carbon quantum dots (blue emission) increases with quantum yield?
I am a master's student of environmental science and trying to calculate the GHG emissions from electricity generation industries using the tier 1 method of IPCC guideline and LEAP model. When I searched for some examples through websites and also some papers, I did not find them. So, I am confused about the calculation part, especially for IPCC. Please guide me or give me any suggestions on where I can get the references for that calculation.
I have difficulty when elaborating the positive impact/avoided emission from eliminating plastic/polybag use for tree planting activity. Is there any direct value/rule of thumb reference when eliminating XX kg of plastic?
How to improve the efficiency of the above title!
