ResearchGate Q&A lets scientists and researchers exchange questions and answers relating to their research expertise, including areas such as techniques and methodologies.

Browse by research topic to find out what others in your field are discussing.

Browse Topics

  • Ahmed Abdelraheem added an answer in HFSS:
    Should results substantially vary if I use "Lumped Port" rather than "Wave Port" as an excitation?

    I am simulating an UWB power divider and I am getting entirely different results if I change the excitation  from "Wave Port" to "Lumped Port". I would like to notice that this happens the same way in HFSS and CST i.e. in HFSS if I use waveport then change to lumpedport, results before and after change entirely the same way it does in CST when I use waveport then change to discreteport.

    Ahmed Abdelraheem · Military Technical College

    Got it, Stanislav. Thank you :)

    Zinal, Thank you :)  But how can you explain they do not substantially vary, actually they almost vary at all, in the majority of cases ?? 

  • Sandra Diaz Garcia added an answer in Primer:
    What should I do, if I have primer dimer?

    I've done annealing optimization from 40-68oC, i still dont get any band except primer dimer. I tried increased Taq concentration up to 5 unit and DNA concentration up to 30ng but still dont have any product except for primer dimer. So what should i do?

    Sandra Diaz Garcia · University of California, San Diego

    Hi! If you've already tried all the suggestion above, i will suggest you use Betaine to avoid secondary structures formation.. maybe it can help you.. http://www.ampliqon.com/media/25849/betaine%20enhancer%20solution.pdf

  • Jacob Yu asked a question in Lettuce:
    How do I phenotype lettuce for essential nutrients such as Fe, and Ca?

    I am breeding lettuce for increased levels of iron and calcium. It is too time consuming to take extracts of every plant and test for Fe and Ca concentrations. Is there any faster way to screen thousands of lettuce plants to select the ones with high levels of Fe and Ca?

  • Deepti Tomar asked a question in Knockdown by miRNA:
    Is pSuper.neo.gfp vector a suitable system for stable microRNA over-expression or knockdown for its functional characterization?

    I am planning to use pSuper vector system for over-expressing and knocking down a microRNA in breast cancer cells. Although it was initially designed for the purpose of siRNA expression, I am not quite sure about its suitability as far as miRNA expression is concerned. Also, I also would like to know that whether cloning a sequence antisense to a particular miRNA in the same system can efficiently result in knockdown of that miRNA.

  • Antonio Serrano added an answer in MLR:
    Can anybody suggest the protocol for the interpretation of MLR ( mixed lymphocyte reaction) data using MTT assay to measure cell viability?

    I need to check for the MLR (Mixed lymphocyte reaction) for the particular cells using MTT assay. I have to co-culture the responder cells (CD8 T cells) from one mouse strain with the stimulator cells (irradiated APCs) from the another mouse strain. Since I am planning to measure it by MTT assay, what are the important controls which I should use? Also, after measuring absorbance at 570 nm, how should I interpret the results from that, i.e. how should I determine the % viability of each sample?

    Antonio Serrano · Hospital 12 de Octubre

    You car evaluate lymphocite proliferation using MTT and other similar products as Roche Cell Proliferation Reagent WST-1, a water soluble derivate of MTT (yellow color) than you can read as a ELISA at 450 nm.WST-1 is more sensible.

    You can see our  protocols in two of our publications, that you can download from reseachgate:

    For MTT:  Serrano, A et al. Arch Biochem Biophys. 1998 Feb 1;350(1):49-54.

    For WST-1: J Immunol Methods. 2014 Jan 31;403(1-2).



  • What is philosophy of mathematics? What is it for?

    1, philosophy of physics once placed a significant role to solve defects in the foundation of physics disclosed by paradoxes; it is hopefully that philosophy of mathematics will do the same.

    2, the infinite related paradoxes have been troubling us for such a long time------the fundamental defects are not only mathematics and not only philosophy. Is it the faults of our not having been done enough on “philosophy of mathematics”?

    3, driven and powered by the newly discovered infinite related Harmonic Series Paradox, we have very clear target------hoping to solve some of the infinite related fundamental defects in our mathematics through the discussions here.

    Marcel M. Lambrechts · Centre d'Ecologie Fonctionnelle et Evolutive, Montpellier, France

    Just for discussion:

    Are infinite numbers like symbolic UFO's? Many people talk about it, but they are never observed?

  • Does anyone know of any academic literature on PODEMOS in English?

    I have searched everywhere for literature on Podemos and I have found it extremely hard to come about in English since they are a relatively new party only founded in 2014.

    Cristina Blanco Sío-López · European University Institute

    The following book:

    Asaltar los Cielos

    by José Ignacio Torreblanca, Debate, 2015

    ISBN 9788499925073


  • Neven Vukorepa asked a question in Soft Tissues:
    Can someone give me some scientific articles about IASTM (Instrument Assisted Soft Tissue Mobilization) technique?

    I'm interesed in benefits of IASTM therapy.
    Thank you!

  • What are the differences and similarities between economic growth and economic development?

    To what extent are the terms mutually exclusive, and to what extent are they not?

    Mark Anthony Martinez · California State University, Bakersfield

    A broad way of looking at the issue in real time is to compare what the European Union was designed to do and what the North American Free Trade Agreement (NAFTA) was designed to do. The EU has always focused on regional development by insuring that there would be transitional aid to help economically weaker countries develop and prosper. This was part of a broader post-war mission, that few recognize today.

    NAFTA, on the other hand, was effectively a series of commercial agreements between established industries that focused on the promise of markets bring prosperity on their own. In many ways, the NAFTA framework is being copied by those building the Trans Pacific Partnership. 

    The EU always understood that there would be adjustment costs to promoting growth and development, and prepared for it. NAFTA was a commercial agreement that was not at all about free trade (how can you have a capitalist free trade area when one of the primary factors of production - in this case labor - is not mobile?). The EU was always about development, while NAFTA was about economic growth for specific industries and the myth that a rising tide magically lifts all boats.  

    Operationally, then, economic growth is a generic term that conveys economic activity while economic development focuses on  the factors that Hussein Elasrag, Hasan Mohsin, et al. discuss. At the end of the day, the state creates the conditions under which wealth is created, which includes pushing policies that make the market work for everyone ... 

  • Arnold Trehub added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Arnold Trehub · University of Massachusetts Amherst

    Marc: "SMTT experiment results: According to many authors such results are explained in the general context of anorthoscopic phenomena."

    All of the publications that you cite simply describe aspects of anorthoscopic phenomena. The do not provide any kind of neuronal explanation for my SMTT results in terms of underlying brain mechanisms. So you have given no alternative explanation for the SMTT results.  

    Marc: "You specifically drew our attention to Larsen et al.'s 2006 paper "Images of illusory motion in primary visual cortex" as a proof [emphasis mine] of the existence of the retinoid system."

    This is a blatant misrepresentation of what I wrote. I simply suggested that the Larsen et al finding gives strong empirical support for the role of the heuristic self-locus (I!*) in path tracing and illusory motion. Experimental results cannot prove a theoretical model, even though they can add to the theoretical validity of a proposed model.

    Marc: "... Larsen and Bundesen in their 2009 paper the fMRI images of Fig 6 should show the whole retinoid system and not only the V1 area and MT area located approximately at the junction of occipital, parietal and temporal cortex."

    I don't see how you can possibly make this claim for a system of mechanisms that are  widely distributed in the brain, and for which the authors made no attempt in their experimental design to find and image. Tausif is probably better able than I am to explain to you why your expectation is unreasonable.

  • Neaman Teimouri asked a question in Data:
    Does anyone have data set of one water distribution network with its manometric datas in some nodes?

    Preferably,Pressure data for Fossolo Water Network.

  • How can I manufacture open cell structures within polyurethane foam ?

    Which additives or techniques can produce open cell structures or big bubbles in a 2 component polyurethane foam?

  • Om Prakash added an answer in Animal Science:
    How can we measure suckling duration per bout?

    I am pleasure to read your answer 

    Om Prakash · Indian Veterinary Research Institute

    A "suckling bout" was defined as the period the pup suckled, including any short (<2 min) breaks during this bout. Bouts of <2 min were excluded from analysis. An "intersuckling bout" was defined as the interval between suckling bouts, provided these were longer than 2 min. These definitions of suckling and intersuckling bout, while arbitrary, follow Goldsworthy (1992) and Oftedal et al. (1987), who considered a suckling bout to consist of both suckling on the teat and the short breaks as pups changed teats.

  • How can I prepare asymmetric bidentate Schiff base ligand?

    How can prepare a condensation product of a primary diamine and two different aldehydes without have too many side product?

  • Joseph Mwema added an answer in Biometrics:
    What should I test for in a biometric fingerprint encryption algorithm?

    Other than testing for efficiency, reliability and speeds in a biometric encryption algorithm. What else should I test for?

    Joseph Mwema · Jomo Kenyatta University of Agriculture and Technology

    Thanks Ramon. That's true. Would you know of a practical way of implementing cancel-ability of bio-metric fingerprint templates that is easy to learn? I may have to omit revocation of compromised templates for now in a project I am working on until I figure out how to go about it.

  • Tayyebeh Mohammadi added an answer in XFEM:
    Anyone familiar with XFEM/ scripting in ABAQUS?

    I have a RC beam with Concrete Damage Plasticity Model .

    I want to implement XFEM taking the first crack of my RC beam as the initial crack of XFEM, or in other words I want XFEM to start in the middle of the running time of the programm using the results prior to that. To accomplish this is possible by scripting within ABAQUS /or I need to link it with Fortran /Matlab etc.

    Also please mention any good  links of studying scripting in ABAQUS

    Tayyebeh Mohammadi · Marquette University

    You can assign "concrete damaged plasticity model" and " XFEM criteria" to the concrete material together. Before crack initiation criterion is met, the concrete behaves according to the "damaged plasticity model". When the crack initiation criterion is met, the concrete will crack and the crack will propagate according to the defined damage evolution. I think you don't need to use subroutine for that.

  • Alina Lartseva added an answer in Arousal:
    How do I transform negative emotion, i.e. fight or flight, in terms of valence and arousal?

    Negative emotion is usually referred as "fight or flight" state. Within 1 to 10 (negative to positive) for valence and arousal, where is the location of this negative emotion?

    Alina Lartseva · Radboud University Medical Centre (Radboudumc)

    Fight or flight is not really an emotion but rather a behavioral response that follows from an emotional state (such as fear). In any case, I assume you were looking for something like this?

  • Can you please share your experience in comparing MM/GBSA and TI methods for free energy calculations?

    In your experience which one is better to understand the relative binding free energy and comparing them with experimental outcomes and why?

  • Judocus Borm added an answer in DICOM:
    How i can measure optical density to gray scale image by image j ?

    I get dicom image of abdomen ct after convert it from JPg frmat  by dicom converter

    when use image j ( plot profile ) to measure density of same area withe different image contrast the results which got it not acceptable, in another words not suitable for theoretical .

    any one can give me a good idea about that . thank u all

    Judocus Borm · Reinier de Graaf Groep

    Any image from a CT that is converted to JPEG format cannot be used reliably to read out the attenuation in Houndsfield units ever!

    That image format uses image compression and other image proceeing NOT DESIGNED to preserve such properties. DICOM lets you save JPG files through a form of encapsulation, so it can administratively be handled correctly and safely. That is, the image data will be registered with meta data such as what patient is involved, when and where was the study performed and so on.

    JPG files are only intended for screen-captures / medical photographs, not to store CT's.

    Any modern CT can, at least for the past 15 years, produce a DICOM file format that preserves all image properties directly. Only those images preserve the correct values.

    The DICOM standard defines a lot of different file formats for different purposes. Dicom encapsulated JPG is totally unsuitable for the storage of native CT data.

    But even if you have the original  DICOM CT data available, you must wonder whether the unmodified CT data actually are suitable. The Houndsfield unit has serious limitations. Therefore in radiotherapy al lot of effort must be put into calibration and transformation into electron-density maps.

    Houndsfield units are NOT equivalent to optical density .

    Therefore: Please state the purpose of your project?

    image J can be fed any garbage and be made to produce output.

    Any use of JPG as an intermediate format between a calibrated medical image format renders the result useless for purposes of measurement of attenuation.

    In addition the resulting JPG image is not suitable [while not designed for] further post-processing, as even [small] feature sizes are not guaranteed to remain conserverd.

    It is not that difficult to load DICOM CT data directly and several such software packages are available in the public domain.

    If you are confused by some of my statements, ask any clinical physicist on a radiotherapy department for advice. They take such details very, very seriously for good reasons.

  • Ricardo Matias added an answer in Shoulder Surgery:
    What is considered the best treatment for the frozen shoulder? How? Outcome
    Specify modality and outcome
    Ricardo Matias · Instituto Politécnico de Setúbal

    Some good resources to look into from evidence-based practice guidelines to modalities:


    Good luck!

  • Vladimir Farber asked a question in GUI:
    Which practical recommendations/references and links can you give to simplify understanding how work with Matlab's Graphical User Interface (GUI) ?

    I want start using the Graphical User Interface (GUI) of the MATLAB, since I think that it can be very useful in performing simulations. Can somebody give relevant links/references/video lessons. Thank you in advance!

  • Sezer Okay added an answer in Genetics:
    Do transposable elements (TEs) indicate that cancer is an adaptation mechanism?

    Approximately 45% of the human genome is comprised of TEs.  TEs are not simply "junk" DNA. The effects of TE insertion in the genome varies from negligible to disease conditions suh as cancer. On the other hand;TEs activity can play an essential role in the host response to stress, facilitating the adaptation of populations and species facing changing environments.  Enhanced TE mobility has to be sufficient for generating broad genetic variation within the host genome, and that this genetic variability is genetically transmissible to the next generations.

  • Does Collective Intelligence Exist?

    Simply put: I'm interested in how groups 'think,' 'learn,' 'perform,' and in turn; how this relates back to the individual.

    In particular, I am currently undertaking a Ph.D. on the topic of 'Collective Intelligence' under the supervision of Prof. John Hattie

    I am fascinated by the idea of expanding the typically individualistic notion of 'Intelligence' and 'Intelligence Testing' and applying these psychological subdisciplines to 'groups' of two or more people.

    For example, is there such as thing as a 'Collective Intelligence Factor' that distinctively represents the intelligence of groups (e.g. two or more people) and if so does this 'c-Factor' set the group apart from the intelligence of its individual members?

    In other words: is the Collective Intelligence of groups greater than the sum intelligence of its individual members?

    How can this collective intelligence be measured?

    Does 'group learning' translate to 'group intelligence'?

    Can we use existing psychometric tests (e.g. IQ tests) to measure and predict cognitive differences in groups?

    What makes one group more intelligent than another?

    Do groups made up of highly intelligent members demonstrate higher 'collective intelligence' and outperform groups made up of low or moderate intelligence members?

    If you have any links, papers, conferences, or general thoughts that would help me explore these ideas; i'd love to hear from you.

    Susana Urbina · University of North Florida

    I don't know about "group" intelligence, but there is certainly something like more intelligent cultures, thus cultural groups or subgroups. I am thinking about the Jewish culture in particular. I was stunned to find the number of Nobel prizes in various disciplines awarded to people of Jewish background (I am not Jewish). It's something close to 50% of all prizes. You can look it up. Why is this? I believe that this is because for reasons related to the history of Jewish people, their culture has promoted and valued learning and education, thus resulting in efforts within the family to foster and stimulate intellectual development in children. Another exaple would be Sweden.

  • Is anyone familiar with a protein concentration method for western blotting?


    I'm using a new protocol for subcelular fractioning for rat striatum and frontal cortex. Unfortunately, I'm obtaining little protein in fractions (nuclear, sinaptosomal and non-sinaptosomal), especially in the striatum. I already used a pool of the cerebral regions but it's not enough.

    Thank you

    Inês Pita

    Christopher Bradley · Lattice Biologics, Inc.

    If you're simply planning on running your isolated protein fractions on gels in order to visualize by western, you can TCA precipitate a larger volume to give you more protein to load. Make sure to wash several times (usually with cold acetone or after your initial TCA precipitation) to remove acid. Here's a simplified protocol: http://www.its.caltech.edu/~bjorker/Protocols/TCA_ppt_protocol.pdf

  • Remi Cornwall added an answer in Maxwell:
    Is electromagnetic radiation produced by the electron's acceleration or a Flip-Flop?

    Since Maxwell suggested that Electromagnetic Radiation (EM-R) is produced due to electrons acceleration, a new mechanism based on the Flip-Flop of electron is recently suggested with comparison to Maxwell mechanism, in a paper title “The Electromagnetic Radiation Mechanism” at: http://fundamentaljournals.org/ijfps/downloads/68_IJFPS_Sept_2014_72_79.pdf

    Do you think the Flip-Flop mechanism offer better explanation?

  • Does ethics prevents supply chain competitiveness?

    Does ethics prevents supply chain competitiveness? How? In what way?

    Wallace R. Wood · University of Cincinnati

    The big ethical issue in logistics is treated differently inbound than outbound. Firms despise their employees taking bribes or being influenced by suppliers, but the same firms authorize and fund the exact same bribes and influence to sell products. Buyers have loyalty to their employer, but if I give my dog dry crumble biscuits and you offer him bacon, he is your dog.

    The best defense against choosing for personal incentives instead of choosing for price, and quality of service is for collusion to restrict competition to price and quality, but setting rules of equal incentives to buyers. Drug companies as bad as they are, colluded to even and limit gifts, trips, and trinkets to doctors. NCAA coaches all recruit under near bribe but equal rules, to help high school athletes choose by education and playing opportunity, with cash, or incentives equalized.

  • Vinesh Kumar added an answer in Plant Extracts:
    Can we use the expired antibiotic disk for disc diffusion test?

    i want to screen the antibacterial activity of the plant extract. and i will be used tetracycline or ampicilin drug as the positive control.  However, the one that i have right now is already expired. Can I still use it in the test? Thank you.

    Vinesh Kumar · Gautam Buddh Technical University


    my answer is no. it is because can anyone eat expired medicine and it can show other effects on bacteria also. so my suggestion is you take new drug for your study. 

  • Poling of Piezoelectric Materials . What is the condition for poling such piezo material ?

    What is the condition for poling such piezo material .

    1- how can I predict poling temperature ? does the poling temperature related to ( or depend on ) Curie temperature .

    2- How can I predict the poling voltage

    3- Researcher normally use Silicone oil with poling of Piezoelectric . can I use glycerine or paraffin oil instead

    4-does the Poling with ultra High voltage ( or voltage grater than normal temperature of poling ) affect on the result ( d33 , K , and dielectric constant )

    5- Now I am working on Bismuth( Sodium , Potassium )  titanate - Barium titanate - Bismuth ferrite .  any suggestion on poling these materials ( ceramic ) .

    veera gajendra Babu · Manonmaniam Sundaranar University

    Poling field can be calculated as 2 or 3 times of coercive field.

    Poling conditions for samples you asked are

    1. Bismuth(sodium, potassium) titanate-poling field is 3-4kV/mm at 80deg. C for 5 min. 

    2. BaTiO3-poling field is 2.5-3kV/mm at 80deg.C for 5 min

  • Have primate species other than Homo sapiens engaged in acts of aesthetic creation?

    For several years some scholars have accepted the engraved pieces of ochre from Blombos cave in South Africa, at least one of which has a geometric cross-hatched pattern, as evidence of early modern human aesthetic creation (ca. 75,000 BC). See: Henshilwood, Christopher S.; d’Errico, Francesco; et al., “Emergence of modern human behavior: Middle Stone Age engravings from South Africa,” in Science, new series, vol. 295, no. 5558, February 15, 2002, pp. 1278-1280 (http://www.sciencemag.org/content/295/5558/1278.abstract?sid=da7c3755-b2bc-4ced-93da-2c024c50b1fd, access: March 14, 2015).

    The recent discovery of similar engravings on shells on Java, from ca. 500,000 BC -that is, long before the emergence of modern Homo sapiens-, suggests that aesthetic creation evolved gradually. See: Joordans, Josephine C. A.; d’Errico, Francesco; et al., “Homo erectus at Trinil on Java used shells for tool production and engraving,” in Nature, December 3, 2014 (http://www.nature.com/nature/journal/vaop/ncurrent/full/nature13962.html, access: March 14, 2015).

    Suggestions that chimpanzees make aesthetic decisions while painting are intriguing. See the following texts and video:





    Can anybody point me toward additional studies on aesthetic creation by nonhuman primates, either in the archaeological record or among our contemporary primate cousins?

    David Charles Wright-Carr · Universidad de Guanajuato

    Derek: Thank you for this inside look at an ongoing debate, and for the reference to your recent article (2014). I managed to download it through my institutional access.

    I am reminded of the discussions among scholars looking at the Mesoamerican pictorial visual communication system, which is hard to label in Indo-European languages because conceptually it straddles the blurry border between what people consider art/icons/pictorial representations and writing. We quibble over definitions, often engaging in debates where we seem to disagree about things that we really agree about, the main disagreements being about what to call these things; of course the labels tie into theoretical trends extending through time and space. Through all of this, it is imperative to keep our variables separate. For example, the gradation between motivation (representation of material things and beings) and arbitrariness (abstraction) is independent of that which is being signified (in the case of Mesoamerican signs, ideas or linguistic structures like words, morphemes, and phonemes).

    I like your use of neuroaesthetics (if you will permit the use of this label), or paleoneuroaesthetics (taking even greater license with the labeling game) in reference to the Middle Paleolithic geometric engraved paterns from several African sites. It seems well grounded, in harmony with recent transdisciplinary research on how what we now call "art" resonates in the embodied mind.

    As for the possible meaning of these patterns, there doesn't seem to be enough relevant information to do more than lay out several alternative hypotheses. Ethnographic analogy may give us some insight, but the distance separating us from the Middle Paleolithic limits this approach. Still, your neuroaesthetic explanation does not rule out the possibility of symbolic content being assigned to geometric patterns; throughout the prehistory and history of our species form and content have coexisted in our aesthetic creations, reinforcing and enhancing each other. I'm not saying that this is necessarily so, just that I don't see how the possibility of iconic meaning can be rued out. At the other extreme, an alternative hypothesis that popped into my head while looking at your figure 1, in which the saturated color of the ochre is superimposed over the engraved lines, is that the folks at Blombos Cave were just scratching into the surface to test the optical properties of their pigment source. Along with form and content, materials and techniques are another basic aspect when looking at material aesthetic creations. Of course the regularity of the scratches would still have to be explained, and your paleoneuroaesthetic approach works nicely here.

    Finally, I would like to point out that the following paragraph from your article of 2014 seems to make sense in the light of what has been discussed on this thread, including chimp paintings and such:

    "The pleasure derived from creating patterns therefore derives from the fact that artificially produced geometric forms serve as an externally derived supernormal correlate of the patterns processed by the early visual cortex leading to a sense that the world is being disambiguated correctly, which forms the basis of a proto-aesthetic awareness. In sum, when viewing repetitive-like patterns, the early visual centres become hyper-stimulated leauding to an undifferentiated sense of arousal, which results from the fact the early visual areas are pre-tuned to respond to such lines because they play such an important role in the discrimination of objects in the world. Interestingly, certain implicit (preconscious) processes have been linked to the predilection for geometric forms to the extent that observers are not always aware why they prefer such motifs, which is referred to as preference without inference [...]" (p. 64).

  • veera gajendra Babu asked a question in Impedance:
    Large d33 value but small phase angle, what is the reason for that?

    I have got comparable d33 values with literature for my samples after poling, but the phase angle was very small (10 degree). I got number of resonance and antiresonance peaks in my impedance spectrum. Why i can't get phase angle above 80 degree even i had high d33 values?.. I poled the samples at RT. Please clarify the doubt sir. 

    Thanks in advance