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  • Jiří Adámek added an answer in Ceramic Materials:
    Is there any chance to melt Ni3Al dice (4,5 mm) on oxide ceramics in resistance furnace under Ar atmosphere ?

    We used a lot of types of oxide ceramics based on Al2O3 and even used Spinel (MgAl2O4) ceramics - refractory concrete, which is even more stable, but Ni3Al always oxidized and not melt. We are trying to reach molten state of Ni3Al to measure wettability of ceramic materials and Ni3Al. Do you have any advices ? Thanks a lot

    Heating speed: 5°C/min

    Ni3Al is non-alloyed

    Oxide ceramics - many types - Al2O3 up to 82%

    Jiří Adámek
    But ZrO2 IS extremely expensive material. We are trying to melt thin alloy on premium refractory materials - but with good price ratio - like mullite-corundum.
  • Douglas Nuttall added an answer in Natural Resources:
    How is Climate Change a global threat to management of natural resources?

    History of Climate Change.

    Causes and Effects

    Douglas Nuttall

    I'll pick forestry as an example, but it applies to all forms of management of natural resources.

    We know how to do forestry that will ensure the wood stock is maintained within a fairly well understood range.  When climate changes, the rate of wood growth and natural destruction (fire, pests, disease, etc)  will both change, in substantially unpredictable ways.  We have ingrained patterns (laws, mores, traditions, experience, etc) that will prove to be resistant to adaptation as fast as the climate changes the underlying conditions.  Thus, over-harvesting becomes a real risk, and one we can't see coming.  We will see efforts to protect endangered species (who may not be able to adapt or migrate quickly enough) and to make up for losses in agricultural production will stress our forest management methods.  We will see tree poaching increasing, economic demands for increasing harvest, and other synergistic effects that are only slightly connected to climate change.  These synergistic feedback mechanisms will also be generally unpredictable, and start as 'noise in the signal' until they are major effects and possibly too severe to correct for.

    This pattern would be repeated with agriculture, water resources, waste assimilation, built environment, etc.  Stuff will shift, and we won't amend our patterns quickly enough, leading to the collapse of specific resources in specific locations.  In some of these locations, the specific resource is the critical resource for the population, and an alternative may not be available through trade - population crash would be inevitable.  That triggers either massive local die-off, or massive resettlement (which we have recently proved is not encouraged by the rich countries of the world).  Without a population that is working, the resources that could have been made available from an area of depopulation won't be extracted and traded with other areas, exacerbating the problems.

    With a little imagination, you could work out the positive side of climate change, too.  This would include the tundra being able to support crops, the growing season of temperate areas lengthening, etc.  But that wasn't the question, so I'll leave it alone.


  • Jaga Mohan Meher added an answer in Astringents:
    How to evaluate tannins astringency ?

    mainly in red wines 

    Jaga Mohan Meher

    Tannin concentration was measured according to the method of Ribe´reau-Gayon and Stonestreet . Two tubes with 4mL of previously diluted (1:50) wine, 2 mL of distilled water, and 6mL of HCl (12 N) were prepared and hermetically sealed. One of them was heated to 100°C in a water bath, and the other was maintained at room temperature. After 30 min, 1 mL of ethanol (95%) was added to both tubes. After stirring, absorbance at 550 nm was measured. The tannin concentration was obtained by multiplying 19.33 by the difference between absorbances

  • Leigh Aldous added an answer in Potentiostat:
    Potentiostat and Dr. Bob's cell for small-scale SIMPLE electrochemistry RedOx Reactions??

    Our chemistry department just acquired a Gamry Interface 1000 for electrochemical detection. We also bought a Dr. Bob's cell to start learning how to use the potentiostat. I want to know what simple RedOx reactions I could try with this cell just to get a sense of how the potentiostat and the electrodes work. Any help will be really appreciated. Thanks!

    Leigh Aldous

    I'd recommend looking at something simple like ferricyanide in water. 

    The (discontinued) magazine Current Separations has a lot of useful application notes, like one on ferricyanide - http://www.currentseparations.com/issues/15-1/cs15-1d.pdf

    You can find the rest of the issues (and some useful articles) here - http://www.currentseparations.com/issues/

  • Lee Lee added an answer in Real Time Applications:
    Why is NTC amplification occurring in my SYBR green assay?
    I have been running a SYBR green assay and noticing amplification in NTC and negative control. However the positive samples are giving me early ct values compared to NTC and negative control. I tried changing both the annealing temp and the primer concentration, but nothing is helping. Any suggestions? Do I have to change the primer or ignore the NTC as it gives a later ct in the range of 32 and the melt curve looks so good without any bumps.
    Lee Lee

    It was two years ago but allow me to bump up the question Johan. I am dealing with the same problem currently, wondering whether you have successfully solved the problem.

    In my opinion, the amplification in NTC should take in consideration for the developed assay validity. The amplification impling presence of contaminant in the assay. I am thinking maybe the culprit is the contaminant from pipette. Correct me if I am wrong. Thank you.

  • John Sosa added an answer in Convexity:
    Detect convexity in an image

    I have an image consists of some components, How I can recognize, in MATLAB, every component is convex or not?

    John Sosa

    I'd like to strongly recommend you take a look at our new software MIPAR at http://MIPAR.us. We have tools that would make it very easy to classify objects by convexity, either using moment invariants or convex area / area ratio. If you'd like to post an example image, I'd be happy to make a recipe file for you and show you what we can do. MIPAR is actually written in MATLAB, but runs entirely standalone without the user needing MATLAB installed. Finally, in MATLAB you may find help in using the regionprops function to measure an object's convexity, but this requires segmentation and labeling of the object, a task which MIPAR helps make very easy.



  • Bisrat Gezahegn added an answer in MATLAB Simulation:
    How active power filter (APF) controller prototype developed from matlab simulink result?

    i want to produce a prototype for APF controller  from my matlab simulation results. So i kindly request you to suggest me the material that  helps me to develop hardware for APF controller. 

    Bisrat Gezahegn

    Thank you,Mohamed Abdelrahem

  • Sasidharan S Lucky added an answer in Protein Biochemistry:
    How to find out the number of dye molecules attached to peptide following conjugation reaction?

    I conjugated my 26 aminoacid peptide (MW: 2850 ) with Alexafour 488 (MW : 840). Using the formula found in the kit: protein concentration (M) =(A280-(A494 X 0.11)) x dilution factor / 5570 (where A280 and A494 is the absorbance of the conjugated peptide at 280 and 494 respectively, 0.11 is the correction factor , 5570 is molar extinction coefficient of the peptide. The degree of labeling was found from the formula = (A494 x dilution factor)/(71000 x protein concentration); where 71000 is the molar extinction coefficient of the dye at 494 nm. Using the 2 formulas above, I found that there was 0.2 moles of dyes per mole of peptide. How can i derive the number of dye molecules conjugated to my peptide? 

    Could this mean that there are unlabeled peptides? How can this be removed? Free dye was removed using gel fitration by zeba spin desalting column (7 MWCO).

    Sasidharan S Lucky

    I think Prof. Hussain is right, the absorbance was not linear and this peptide in known to exist in a tetramer form in solutions at high concentrations. Hence, my calculation might not be right. However, I feel that the conjugation procedure did work, as I am able to detect co-localization of the labelled peptide on the cell and nuclear membrane, exactly where it is supposed to be present. Just that the calculation part is wrong.

  • Susantha Jayasundara added an answer in Soil Microbiology:
    As nitrification inhibitors fertilizers act on the activity of Nitrosomonas bacteria?

    What fertilizers nitrification inhibitors have considered that affects the activity of bacteria Nitrosomonas? As this process occurs? Does this not affect the activity of other microorganisms that are present in the soil?

    Susantha Jayasundara

    For sure, the effectiveness of Nitrification Inhibitors (NI) is not permanent.  That is the reason why repeated applications of NI are necessary.  It is not known yet, the unintended effects of repeated application of these compounds on non-target microbial community, simply because research on that aspect is extremely limited.  Here is one example that reported DCD or dicyandiamide (one of most commonly used nitrification inhibitors), entering waterways via shallow groundwater seepage and having an inhibitory effect on in-situ nitrification in aquatic ecosystems.

    Smith I. and Schallenberg, M. (2013) http://www.sciencedirect.com/science/article/pii/S016788091200326X

  • Veysel Gökbel added an answer in Higher Education:
    What are the main topics in a description of a higher education system?

    When you look at a higher education system, which aspects build the story of that system?

    Veysel Gökbel

    Dear Bilola,

    Among many possible answers, I want to add that educating and preparing students to the life is one of the main topics and responsibility of higher education systems.

  • Crestore Lex Tapia Capiña added an answer in Combustion:
    Anybody knows the heat of combustion of hydroxyacetone?

    standard heat of combustion 

    Crestore Lex Tapia Capiña

    thankyou so much Dr.Braissant 

  • Mudassar Sayyed asked a question in C:
    What methodology to use when i am assessing three components on a scale of 1 to 5?

    I have asked following question to 40 subjects.

    How much did the following component help you in assessing relevance of source page?

                                                                     None                                     A Lot  

    A                                                                1             2         3        4       5

    B                                                                1             2         3        4       5

    C                                                                1             2         3        4       5

    I hypothesize component C is more helpful in assessing relevance of source page than component A and component B.

    What methodology should i follow to test my hypothesis?

  • Rocktim R Das added an answer in Shell:
    Help me to identify these shells.

    These species of Mollusk recorded from one of the sampling site of Mine. Bhavnagar, Gujarat, India.

    date and time is there in the photo.

    Rocktim R Das

    Hello Devendra

    I agree with all the above answers, moreover a close photograph with a clear aperture is required. 


    Rocktim R Das

  • Saisudhakar .. asked a question in IP:
    Which one needs to be considered in the calculation of IP/EA? Either Adiabatic Approximation or Vertical Approximation?


    I want to calculate Ionization potential (IP) and Electron affinity (EA) for a conjugated molecule using some computational package. Among the two approximations (Vertical/Adiabatic), which one needs to be preferred for these calculations.

    Thank You

  • Pablo De La Cruz asked a question in Local Knowledge:
    How cultural knowledges are constructed in a global society?

    Does some one know sociologists and anthropologists who have dealt with the problem of how knowledge is constructed, and particularly cultural (traditional, local) knowledge in indigenous communities? I´m looking a good theoretic background that allowed me to understand knowledge as a social construction.


    Pd: Add you answers in english, spanish or french!! 

  • Veysel Gökbel asked a question in GrADS:
    Which one do you suggest more? Completing dissertation asap or Engaging more in research and teaching as grad student?

    If someone has two conflicting options in allocating time as a doctoral student, what do you suggest based on your experience?: 1-More engagement in teaching and research activities while doing PhD is better than moving further in the dissertation. 2- More concentration on dissertation to complete ASAP is better than engagement in teaching and research experiences.

  • Partha Sarathi Mohanty added an answer in Multiple Sequence Alignments:
    How to derive a evolutionary rate (in numbers) from the phylogenetic tree?


    I have a multiple sequence alignment of the highly diverged sequences .

    I have generated a phylogenetic tree of the multiple sequence.

    Is there any way that we can derive the evolutionary rate from the phylogenetic tree?

    Is there any protocol to find the evolutionary rate?

    Thank you!

    Partha Sarathi Mohanty

    Hi Dear

    Beast software is the best way to predict parsimony informative sites. If you r unable to run the software then try MEGA software.

  • Alma Rose Snyder added an answer in Graphic Design:
    Does anyone has references (besides designing interactions book) about the technique 'guided fantasy', by Tim Mott and Larry Tesler from the 70s?

    I have been interested in this technique for a deeper understanding of the mental model of graphic designers and managing procedures of their studio management, but all descriptions of the technique I have found are resumed in Bill Moggridge's book "designing interactions"

    Alma Rose Snyder

    This form of meditation was popular in the seventies when I experienced it in the Unitarian Church and public middle school settings.  I can't suggest any scholarly readings but an online search including the Unitarian Church showed some interesting results (see attachment)

  • Joseph Ntayi added an answer in Education Research:
    What are the most important qualities that PhD supervisors must have to successfully guide a graduate student?
    A good supervisor is a guide and mentor, not an encyclopedia or a self-help book. Many PhD students are not satisfied with their supervisor.
    Joseph Ntayi

    Should be available all the time to attend to students research and other challenges that impact on his/her studies and halp the student to develop a certain level of resilience.

  • Chris K. Elvidge added an answer in Aquaculture:
    What is the reason for gill cover erosion in juvenile Atlantic salmon in aquaculture ?
    This year we have observed massive degeration of gill covers in 2-4 months old Atlantic salmon parrs.
    Chris K. Elvidge

    Unpubished data from a DFO hatchery in Canada demonstrates significant reduction in fin erosion (approaching wild-type) when circular tanks (concrete or fiberglass) are provided with substrate - mechanism being physical erosion of the fins due to contact with the tank material. The fact that your erosion is predominantly on one side suggests this is more of a physical than a chemical phenomenon.

  • Rupesh Gawade added an answer in Epitaxy:
    Can anyone provide information about few queries about GRACE program for lattice (epitaxy) matching?

    1) Which method should be used? a) gaussian b) sixth power function c) 2 with normalization 2) How to get E\sigma value? 3) How much %age of E-value is regarded as significant epitaxy?

    Rupesh Gawade

    Good Morning Mam,

    I am not finding attached link.

    With Best Regards


  • Douglas Nuttall added an answer in Green Economics:
    Does the concept of sustainable development really assure sustainability in terms of Environmental Economics, Ecological Economics & Green Economics?

    Can we really control anything? Do the homo-sapiens have really any control over the other homo-sapiens and/or those things they possess? Is not it largely contingent matter where the dependency of the dependents empowers those who are in control? If it is true that the power to control depends on the level of the dependency of those who are being controlled, then how can we theorize the assurances of sustainability where the term itself depends on the perfect functioning of the related things on which our control is factually contingent in nature? For example, let us assume that the whole world has set the nature free from human interruption, can we then claim it with a cent percent guarantee that we have achieved sustainable development? If the answer is yes, then how the homo-sapiens will be living their lives in the future? Is it possible to bring all the extinctions back from the lost? Is it really possible to compensate all the losses to the nature caused by us?

    Douglas Nuttall

    This is a brilliant question.  Over the vast majority of human history and pre-history, humans lived sustainably.  Only recently have we generally left that way of life (although there are communities that are sustainable in a variety of places around the world), and we are going to return to it at some point in the future - we don't really have a choice in that.  The question is only at what population, and what quality of life.

    Simplicity is in our future.  We can choose today for this to be Voluntary Simplicity, or Mandatory Simplicity (also known as poverty).  If we choose soon, we can choose the first, and decide what we want to do without.  If we choose 'later', we will be left only with the second choice, whether we like it or not. 

    People use their time to meet their wants and needs, or they use their time to convert resources into the means to meet their wants and needs.  The first part of that statement is addressed through Human Development, and the second part through Technological Development.  There is Sustainable Human Development and Sustainable Technological Development, which are distinguished by the time required only to meet needs, and the resources only available in perpetuity to the community.

    I hypothesise that there is no such thing as Sustainable Economic Development, but there would be Economic Sustainable Development - we can't grow in perpetuity, but we can 'grow' into a way of life that can be maintained in perpetuity.

    We will try to use technology to replace the ecological services that have been lost through bad development of the past, to varying degrees of success (both strong and weak theories of Sustainability are true in different situations).  We will ultimately substantially reduce inter-dependency between communities, and increase both resilience and self-reliance (so that bad management from our neighbours won't specifically diminish our capacity to meet our needs).  We will not stop demonstrating our wealth by what we can afford to waste, but we will have significantly less that we can waste. 

    We can continue to harvest nature's bounty, so long as we choose to not extract the capital - only the interest.  Thus far, we've demonstrated we're bad at that.  Market forces that do not recognise the difference have to be eliminated - economics is a tool of society, not the other way around.

    I look at this from the lens of an engineer, rather than an economist.  I invite you to look at my blog at www.sustainabilityengineering.net to see how that vision plays out.


  • Annangi Subba Rao added an answer in Sustainable Agriculture:
    The soils are calcareous and sodic. Cotton and Red gram major rain field crops. Groundwater is poor in quality. What could be the management options?

    The yield levels of crops are also low

    Annangi Subba Rao

    Interesting discussion on an important topic.For managing calcareous sodic soils and for optimizing soil conditions, water is prime requirement. So on farm water harvesting is prime need.Harvested fresh water and saline ground water can alternatively be used for irrigation. If sufficient water can be  harvested, one can go for reclamation of sodic soils using gypsum as amendment. Since the soils are calcareous, one can use sulphur and pyrite also as amendments. Regular use of organic manure will have both ameliorative and nutritional benefits. Crop residue recycing will also improve soil conditions.For N supply  , acid forming source like Ammonium sulphate can be used.For P supply single super phosphate can be used  as souce which contains 50% gypsum.Selection of crops and inter  crops in cropping system are important. As Zn deficiency is well established in these soils ,regular use of Zinc sulphate is a must.

  • Arvind Singh added an answer in Traditional Knowledge:
    How research can help in the conservation of traditional medicines?

    Traditional knowledge of plant based drugs are very important in the remedy of diseases.

    Arvind Singh

    Traditional medicinal plants play very important role in primitive and rural societies in treatment of various ailments. Researches on the medicinal attributes of these plants will bring them in limelight consequently they would not only get protection and conservation in their natural habitats but would also be brought in cultivation owing to their medicinal attributes.

  • Rupesh Verma asked a question in FLUENT:
    ANSYs Fluent UDF based on DPM and period B.C.?

    Is it possible in ANSYs Fluent UDF based on DPM, recycle only desecrate phase without periodic B.C.

  • K. K. Gupta added an answer in Signal Processing:
    I am using cross correlation to find time delay in sinusoidal function. It works fine with small delay.....???

    I am using cross correlation to find time delay in sinusoidal function. It works fine with small delay. However, with relatively large delay it does not give accurate answer. Please claraify my doubt.

    K. K. Gupta

    Filtering will work if some prior information about desired attributes of biosignal. The signal is affected by noise and it is also observed by inaccuracy in long delay time.  If both the signals are having different attributes or snr then different filtering is required. Estimator will also work if you have statistical information about signal.

  • Luis Miguel Constantino added an answer in Biodiversity:
    Are mobile phone apps useful for biodiversity inventory, monitoring, citizen science projects?

    I've been trying iNaturalist and a few other mobile phone apps (Map of Life, eBird, PlantNet, Urubu, SISS-Geo) for over a year and found that many users start but do not continue using them. Moreover, due to the existence of several apps, none of them has a complete list of species and none has all desired functions and features.Citizen perspective:In your experience, do you believe common citizens find the apps user friendly and are able to use them effectively to learn and add data to science?Science perspective:Are scientists, mainly taxonomists, engaging in this initiative to help people learn about nature? If not, why? Is the data generated by citizens, useful for science (biogeography, conservation)?

    Luis Miguel Constantino

    Hi Onildo:

    The Mobil phone apps used to study biodiversity inventory are like digital field guides that continues to improve the more we all use it and add to it. As Chris said, perhaps they are very useful in Europe and United States where the biodiversity is well documented but not in the tropical regions where every day you get new species to science. Perhaps some day we will have mobile apps to study the biodiversity in the tropics. However, the main objective of mobile apps is to make easier and more globally efficient and effective for "citizen scientists" to contribute information during field trips to observe wildlife.


    Luis Miguel

  • Hugo Madrid added an answer in Fungal Biotechnology:
    Which method is best for Identification /Isolation of Brown rot in stone fruits. Mycology ?

    Which method is best for Identification /Isolation of Brown rot in stone fruits?Mycology?  

    Mycology (fungal disease in fruits)

    Hugo Madrid

    Dear colleague, 

    You may incubate fragments of fruit tissue with lesions in a moist chamber and check periodically under the stereomicroscope to search for fungal growth. Conidia or hyphae from different colonies then can be inoculated onto plates with mycological media (MEA, OA, CMA, etc.). These plates must be incubated at 20-24ºC and the morphology of spores and the structures that produce them has to be studied. An alternative is to perform DNA-sequence based identification, starting with an analysis of the internal transcribed spacer region. 


  • Shen-Ming Chen added an answer in Graphene Oxide:
    How to calculate molecular weight of doped graphene sample?

    I have prepared Graphene oxide sample by modified Hummer's method doped it to reduce it. Now I want to make nanocomposite and for that purpose I need to calculate its molecular weight by any means like XPS, Raman or any other characterization?

    Shen-Ming Chen

    It is not a single molecule and well defined molecular formula. Graphen(or doped graphene) is similar to carbon polymers,  we only can say what is the average molar mass in the graphen sample. It also depends upon total mass of the graphene(or doped graphene) sheet or total number of carbon atoms composing the sheet