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Quaternary - Science topic
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Questions related to Quaternary
I am trying to draw Gibbs energy plot of a quaternary system. A Tetrahedron can be a key to the solution of this problem but I am unable to do this. A tetrahedron with colormap ca also help me.
If anyone know about any software that can help me drawing these graphs.
I am trying to thermodynamically model the quaternary system for SS304L Considering Fe-Cr-C-Ni configuration. I need to find out the equilibrium condition during solidification process depending upon the chemical potential of involved elements. It is difficult to visualize the combination of 4 ternary systems to yield one quaternary system for the equilibrium conditions. A Tetrahedron can be a key to the solution of this problem but I am unable to do this in "Thermocalc". My questions
1. Has anyone ever drawn a similar quaternary phase diagram?
2. What are the other possible solutions to see the equilibrium conditions of this system depending upon the common tangent to the Gibbs energy curves?
3. Utilizing the experimental CalPhaD database of this system how can I get the 1) equilibrium temperature during monotectic reaction at 0.02% carbon ( L --> L + Delta ferrite ), 2) equlibrium concentrations of Cr, C, and Ni?
2.Innovative and Combined techniques
4. Radix Converter based
I have carried out quaternization of PVA for antimicrobial activity of the polymer. The sequence of reaction is PVA preparation followed by addition of KOH and then quaternary ammonium salt. Washed with anhydrous ethanol. First time at 0.1 g PVA the precipitates were formed. But at 1 g PVA, after 3 hrs of adding quaternary ammonium salt the curds were formed before the addition of ethanol. Molar ratio of PVA to QAS is 1:2.
Is it due to self-condensation?
Thanks for your response.
I am having baseline issue when following the method outlined in a application note from Agilent. The application note references a method that utilizes a gradient in the attached image.
The whole application note can be found by searching for 5994-3791EN.
I do have a binary pump instead of the quaternary pump, but otherwise there is very little difference between my instrument's config and the reference method that would significantly effect afaik. If Agilent's newer software corrects for the baseline issues seen maybe that could be the answer.
I also have the older Agilent DAD from the 1100 series if that is relevant.
What could possibly be the root cause of the difference in baseline seen here?
The transition dip is seen at other gradients of these same two mobile phases.
I would like to know your opinion about what are currently the greatest unsolved problems or opportunities for further research in palaeoclimatology.
Can any one help me, I have problem with this pollens, I think they are Cupressaceae( In particular Cupressus sempervirens and Juniperus), but I'm not sure about that. Because they are look like spores. In general, they are round and have a small cavity. The following figures shows some of them.
I'm researching about MIS2 (30,000-11,000 B.P) in the Central Zagros, specifically Kermanshah using wetland sediments. In the current era, the growth of Cupressaceae has not been observed in this region. And it can be strange that I see these pollens many times at the different depths . also at some depths they have high frequency, Which indicates that it is not migratory pollen brought by the wind.
thanks a lot.
Nowadays, it can be seen that the affiliation of the universities plays an important role to accept or reject a manuscript by a journal. It seems that the policy has entered the world of the science. Do you agree or disagree? Why?
Is there a software or tool I can use to estimate the primary, secondary, tertiary and quaternary structures of protein using an FTIR spectra?
I do understand that you can use circular dichroism for this but I am looking for alternatives since we have access to FT-IR…
Hello: I have a question: With an identified active fault displacing young Quaternary deposits, what kind of analysis or methodologies are used for evaluating if that active fault has seismic or creep displacement?
Is this open access journal "Quaternary (ISSN 2571-550X)" by MDPI indeed a peer-reviewed journal and is it reputable? I cannot find relevant information about this journal accept for information provided by the publisher (MDPI). Also, there are other peer reviewed sources with a similar name which at a first glance causes some confusion about the reputation of Quaternary, e.g., Quaternary Science Reviews or Quaternary Research or Journal of Quaternary Science or Quaternary International. Any relevant feedback is welcome.
Did they survive after the Eemian and for how long? The actual question would be if they were still around in the Brörup interstadial (MIS 5c) and how much the Brörup fauna differed from the Eemian one (MIS 5e)? Vice versa, when did the mammoth-dominated fauna first appear in Central Europe after the Eemian? In MIS 5b or earlier? Thanks in advance, Micha
The Problem started after replacing the HPLC Pump from Quaternary to Isocratic pump due to pump failure. The configuration was set as the previous set up as Modular 3D LC System and the license for 3D and Isoabsorbance plot is still valid as evident by the presence of spectra option in the toolbar. However, the isoabsorbance and 3D plots are missing in the dropdown menu for spectra as shown in the attached figure. Does anybody have a solution to this problem please?
Geomorphology is not a science. Unlike physics and chemistry it has no empirical basis. No one measured stream sediments or mass wasting over a century, which should have been done in hundreds of locations, under all climates, topography, degree of degredation, etc. It is based solely on experts. In the Sierra Nevada, work like yours is typically off by 2 to 5 orders of magnitude from constraints imposed by field evidence. I'm a serious geomorphologist; been one since 1968, and it takes decades to get comprehensive results. Geomorphology is a belief system, like Christianity, and it's interesting to see how each evolved over time. OK, I'm old. Am finally going to publish a very abreviated, if lengthy paper, on history of Sierra Nevada uplift based on Late Cretaceous to Eocene sediment remnants and Oligocene to Quaternary volcanic remnants in the range. There are about 300 sites.
I am looking for a material like TPE used in OLEDs that has a high electron mobility to add to my Ternary system that can help enhance the PCE of the devices.
My intention is to study the stability of compounds made up of Li, Al, Ge and P with different compositions. For this purpose, I need to plot a quaternary phase diagram, but I couldn’t find suitable software. So would you please suggest me a software which could be used for this work. Preferable if it is free.
Thank you in advance for your cooperation
Earth is here for more than four billion years, but there had been only 5 (including present) major glaciation periods. The usual effect attributed to milankovitch cycle had been acting continuously, is not it?
Does earth switch between Bistable "greenhouse" and "icehouse" modes that are self-sustaining, and disrupt only by biogeological events?
as per wikipedia ( https://en.wikipedia.org/wiki/Ice_age )
- Huronian glaciation coincided with onset of great oxygenation event. What caused it to end?
- What started Cryogenian glaciation? its end coincide with ediacaran biota rise, and later cambrian explosion, but what caused cryogenian glaciation to end?
- what caused andean-saharan glaciation to begin and end?
- Rise of oxygen producing land plant started Karoo Glaciation, what ended it?
- What started quaternary glaciation?
Just provide Brief answers, and links
Several simple gradation parameters are obviously not a satisfactory description of particle size distribution. Is there a function with a few fitting parameters that can describe the particle size distribution generally? The wonderful thing about nature is that it has rules to follow although it is so complex. I know some excellent researches about this question, but these are mainly phenomenological analysis, and their physical basis is not rigorous.
I have completed the indirect dating methods like foraminiferal biostratigraphy and nannoplankton stratigraphy of Quaternary marine core sample.For direct dating of 1000 yr - 2.5 Ma marine core samples which method will be suitable?
I'm interested in your opinion on what processes could be driving changes in this waterfall, at a decadal scale.
Local Maori recall migratory eels were once more abundant upstream of this waterfall and slot canyon. I'm wondering if fracturing process could have contributed to changes (in addition to an erosion, log jams, etc). This is an area of high tectonic activity. Located on New Zealand's North Island, on the east coast within 50 km of the Hikurangi fault with its slow slip and frequent earthquakes. The rock appears to be sandstone (Quaternary).
By my eye, the exit from the slot canyon looks to have edges that are too sharp to have formed by fluvial processes. Also the tilt angle of the slot. Where water enters the canyon we see more rounded edges.
I'm a biologist/hydrologist, so this isn't my area of expertise.
I've attached photos. But, you really need video to get a 3D perspective. Hopefully this video link works (skip to 10 seconds in).
With all of the sample preparation step, you still have significant matrix effect and need standard addition or matrix-matched standard. Would it be quicker if you pass the 1:1 water:acidified methanol thru an Oasis HLB to trap fat (pass thru) and add internal standard to correct for suppression? The IS is not that expensive if you add into the sample at the end.
Does anyone know where I could find reconstructed North Atlantic winter and summer insolation data over the past 50 000 years?
Or, find data from “Berger A. and Loutre M.F., 1991, Insolation values for the climate of the last 10 million of years. Quaternary Sciences Review, Vol. 10 No. 4 pp. 297-317” ?
Thanks in advance!
Please, i'm looking for a copy of a Book : "Principles of Alluvial Fan Morphology ( Dan Bowman )", can you help me to find it ??
The sea level changed in the geological past for example Quaternary sea level change. Do the chemical composition of groundwater change in glacial and interglacial period?
Erdelen, W. and Preu, C. 1990. Quaternary coastal and vegetation dynamics in the Palk Strait region, South Asia—the evidence and hypotheses. In (J. B. Thornes, Ed.) Vegetation and Erosion. London: John Wiley and Sons Ltd, pp. 491-520.
Tried looking for the book but could not find in any of the libraries near me.
Would appreciate if someone can help.
We have a problem with the multi channel gradient valve in a quaternary pump (Serial No. DE62976920) but before replacing it, I would like to know if anyone faced this problem before and could somehow solve it without replacing it.
Our problem is that channel A doesn't take the set volume, so we decided to use the rest of the channels and avoid channel A. However, even when channel A is set at 0%, it is still taking up volume, what ruins the set gradient. Did anyone tried to physically block the channel to prevent it from taking volume or any other more creative solution?
Thanks in advance!
I have been working on ternary and quaternary Cu based chalcogenide nanocrystals. I have measured the UV-vis-NIR absorption spectrum to calculate the band gap. From literature I came to know that the well known method to calculate the band gap is to use the (αhν)2vs hν graph. Where "α" is the absorption coefficient.
How to calculate the absorption coefficient of colloidal nanocrystals from absorption spectra?
This equation is used to predict the glass transition temperature of systems with different components (miscibility and immiscibility). This equation have been used for binary and ternary systems. Can any one know how to extend this equation for quaternary systems?
The Tajik Basin during the Neogene time, it was progressively deformed by folding and thrusting. But in the Quaternary the Tajik Basin suddenly started undergoing uplift and erosion process. A question here is why this happened and what is the consequences have this process ?
DES are often seen as green solvents, however, their chemistry and mechanism is still scarcely available. How do they posses lower melting and freezing tendencies in-comparisons to their original constituents? And what are their potential applications in industry?
I am trying to draw the band diagram of quiternary material which will be used as a quantum well with quaternary barrier. Does anyone know any software that helps to draw this kind of band diagram?
I'm in South Korea.
I want to buy TPQPOH ionomer to do the research of HEMFC.
Is there any place to buy TPQPOH?
Synthesis of TPQPOH is so complicated.
I have been searching for some articles which may address the problem mentioned above. I could find some excellent papers dealing with origin of red beds in sand dunes but hardly any dealing with fluvial deposits of Holocene or Late Pleistocene.
Any help in this regard is welcomed.
1. Ferrocene (Fc) in reduction state could from host-guest complex with β-CD, while the oxidized Ferrocene (Fc+), as reported by many papers, could not stay in the cavity of β-CD due to the decreased affinity between them.
2. Benzimidazole could complex with β-CD under neutral condition, while under acid environment, the protonated benzimidazole escaped from the cavity.
Based on these facts, can I conclude that unfunctionalized β-CD could not complex with positively charged molecules, such as quaternary ammonium?
Has someone ever seen such host-guest system?
THANK YOU ALL FOR YOUR ATTENTION! :)
I am trying to prepare calcium-magnesium alloys with other two elements in it to form a quaternary system by ball milling. I have used toluene as the working media. But everytime while drying samples, when toluene gets evarporated, it was cathing fire.
I have a compaund with four quaternary amine salts (ion bromine). Molecular weight is large enough (7080 mol / g). Which method is best suited for maldi or ESI? Thank you!
i have ester and quaternary amonnium salt (bromine) in same compound. Haw can I hydrolise the ester groups?
Currently I am working on growth of epitaxial ternary and Quaternary III-V semiconductor alloys.
For my research it is needed to know the exact alloy composition using RBS.
So, Please help.
Thanks in advance.
Different aldehydes and aromatic amines that includes quaternary ammonium fragment have not reacted with each other.What can we do ?
In regions where Quaternary deposits and landforms are rare or absent, such as in steep mountainous terrain or other upland settings, we focused on prominent and continuous escarpments and strong lineaments in bedrock. But, what could be the clear evidence indicative of Quaternary movement of the fault?
On the field, we measured pH and alkalinity. From these parameters, I back-calculated the concentration of dissolved CO2 in my samples. They vary between 12 and 23 mg/l (10-2 atm).
The lab also provides us with the concentrations of dissolved CO2 10 times higher than those calculated from field parameters (180-230 mg/l - 10-1 atm. I was expecting to have my samples degassed.
The samples come from a shallow semi-confined to confined Quaternary aquifer (depth of sampling between 25 and 60 m).
I cannot make any sense of it. Any thoughts would be greatly appreciated. Thanks
I am interested in the comparison of historical sedimentation rates as well as mass accumulation rates in sedimentary basins in Quaternary, Pliocene and Miocene. Can anyone supply me with reference? Table would be nice. I suspect that Bengal Fan, Foaz Amazonas, some interior basins are high on the list? I searched but could not find a reference anywhere.
I am looking for any procedure or suggestion on an intramolecular cyclization of a tertiary amine and an aldehyde. The product should be the resulting hemi-aminal. What condition should I use? Do I need to use any Lewis acid (mono dentate) or H+ catalyst? Another confusion I have is, where should the counter anion for the quaternary ammonium come from? Can anyone suggest me? Thanks in advance.
For example the molecular ion of R4NCl and R4NBr or R4NOAc would have same or different retention time in LCMS or HPLC?
I am trying to use MS(materials studio) to calculate the properties of solid solution with multiple elements. but the model is hard to obtain. Anyone can help me establish the model of a solid solution, like FeNiCrCoAl. Or give me some examples about ternary or Quaternary solid solution using castep module. Thanks a lot.
As we know measuring order parameter for binary systems is easy using xrd where we have standard database for the binary systems. But for quinary and Quaternary alloys we don't have database. Can somebody help me how to measure order parameter for multi component systems..?
A quaternary link contains four kinematic links. With the four links, we can form four binary links as shown in the picture attached. But the theory say only three. Why?
Is ther documents or books about the historic geology of the word (from the precambrean to quaternary).?
why alkynyl quaternary carbon peak appears in dept-135 spectra in CdCl3?
Interested in the identification of dentition and bones of vertebrates.
What are the techniques and methods to know If there are any separated sub-phases of amorphous ternary and quaternary systems and what are their compositional elements?
EDX may identify the elemental composition of any system. But, how can I make sure that there are no binary or ternary separated sub-phases have been formed from the quaternary systems? What are the compositional elements of these separated phases?
The adsorption of Pd(II) onto graphene oxide shows optimum pH at 6.0, whereas GO with quaternary ammonium salt shows optimum pH around 3-4.
Attachment for graphene oxide on Pd(II)
The aim of that is to define stratigraphic surfaces and to predict clay distribution.
We study an outcrop formed by Middle Miocene sands and clays, which are expected to be deformed during Quaternary. Thanks a lot for suggestions.
Calcareous plant roots, stems and debris were found within quaternary fresh water limestone environment. Identification of these plants may reveal their environmental and climatic significance.
Was there tectonic activity in west africa craton during miopliocene quaternary period?
I am interested in understanding the solar irradiance of Tropics during Bølling-Allerød period. I am not able to get the data/curve for the said period.
I'm a current masters student and wanted to see if people are aware of knowledge gaps in ENSO activity in South America and/or palaeoclimatology reconstruction needed. I've looked in a lot of literature and seems to be a lot of modelling for ENSO activity not actual proxy evidence, is this true?
I am trying to find out the distance between the Storegga submarine landslide and the Stuoragurra fault, does anyone know the exact distance? Possibly with a reference to a paper?
I aim on freezing the core then splitting it with a saw. However, freezing the core means that I may disrupt the sediment. So, I'm assuming it must be frozen quickly so water crystals don't grow large enough to disrupt the core. What is the correct temperature to do this, have you any advice/experience in this? Is -40'C enough?
Some papers suggested that the formation of deserts (aridification) in Australia during Quaternary was driven by the global cooling, but without detailed interpretation. I want to know how and why and the references. Thanks.
I’m looking for data set or publications on paleoclimate (temperature, precipitation, vegetation distribution) in Europe between 90,000 BP and 50,000 BP
We have a well accepted theory to explain the glacial-interglacial cycles during the Quaternary Ice Age. My question is, why did the Earth enter the ice age gradually?
Would like to learn more about the geomorphology in this region.
Symbols or a legend used in geomorphological mapping varies significantly from map to map and place to place and they are not consistent. The legend and mapping symbols in geomorphological maps are likely to be chosen on the basis of purpose of the output, and hence the legend is not pretty standard with compared to that in other maps like geological. I am planning to compile a geomorphological map in an area where is largely covered with alluvial fills and fluvial erosional landforms. Is there any standard protocol or guideline or any good article on geomorphological mapping that could be useful for reading?
Becky Briant, Fiona Brock and Danielle Schreve are looking for fossiliferous Late Pleistocene sequences with independent age control to include in a new radiocarbon dating project in 2014 which will refine the pretreatments applied to plant macrofossil material in this time period. Have you worked or are you imminently planning to work on such a sequence? Do you have or can you get hold of large quantities (ideally c. 30+ kg [3+rubble sacks] of bulk sediment) of material that you would be interested in including in this project? Can you help? Please email email@example.com for further details.
I'm looking for the paper of Matsumoto (1924) in which the genus was established, the paper in which Palaeoloxodon raised up to rank of genus e and so on. Can you help me?
Especially Betula, Pinus, Corylus, Quercus, Tilia, Ulmus, Alnus, Carpinus, Fagus. From where did each of them come when they successively reappear in the Holocene pollen records of Middle Europe?
From Iberia? Italy? The balkans? Anatolia? The levante? The Mediterranean region in general? East Europe? Central Asia? What is known about their refugia during the Last Glacial Maximum and migration paths thereafter?