Elements Definition and 1000 Threads

I read about a metamaterial today that can separately absorb the electric and magnetic components of an electromagnetic wave, A team of scientists from Boston College and Duke Univ. ... used computer simulations based on prior research findings in the field to design resonators able to couple...

what elements are used to prevent losing neutrons and what are the ways of preventing losing of neutrons in nuclear power plant and atomic bomb?

Is possible some elements (like Cadmium or Bohr) absorb neutrons, without any nuclear reaction in their atomic nucleus? If the answer is YES, then why there isn't any nuclear reaction?

Hello everyone. I'm trying to figure out a trick to finding the degree of (81)^1/5+29(9)^1/5+17(3)^1/5-16 over Q. I know that the degree of this number, call it a, is equal to the degree of the field extension [Q{a}:Q], and also the degree of the minimal polynomial which has this as a...

Homework Statement Let G be an abelian group. Show that the set of all elements of G of order 2 forms a subgroup of G. Find all elements of order 2 in Z6. The Attempt at a Solution The elements of Z6 are 1,4,5. I'm not sure how to find the set of all elements of order 2. Can someone help...

1. Problem Evaluate \int_{-\infty}^{\infty} \int_{-\infty}^{\infty} \int_{-\infty}^{\infty} z^{2} e^{-A \sqrt{x^{2}+y^{2}+z^{2}}} dxdydz 2. Useful Formulae none 3. Attempt at Solution Well, this is part of a much larger problem. I am trying to compute the dipole moment matrix elements...

Homework Statement we shall describe a simple model for a linear molecule, say, CO2. the states |L>, |C>,|R> are the eigenstates of D operator (corresponds to dipole moment) D|L>=-d|L> , D|C>=0 , D|R>= +d|R>. When the electron is localized exactly on the carbon atom, its energy is E1...

[Sorry about the long post] I'm doing an essay where I am exploring whether or not elements were, for the most part, formed under conditions of thermodynamic equilibrium. We know that some element clearly aren't (such as Potassium 40 and uranium which decay radioactivly). I've scoured the web...

If a set contains elements that are *themselves* sets, then would it be correct to say that one of those elements is a subset of the set? E.g. Q = { {a}, {b}, {c} } I know that { {a} } is a subset of Q (because it contains ONE of the elements) But is {a} a subset of Q? I don't...

I know its a rather simple question but if you think about it, it requires much knowledge of d orbital. Is there an easy way a HS student can determine charges of elements using only a periodic table and no prior knowledge of orbitals? My old chem teacher said you could take the element and...

There is much abuzz about the prediction of stable superheavy elements that might exist. Now what I wonder is, did they ever consider that if these particles can exist, why have we not detected them yet. Id have to say if a supernova cannot produce them, we have no hope at all.

This is actually about nanoparticles for better batteries: http://www.technologyreview.com/Energy/20524/?a=f But my point is that nanoparticle fabrication is becoming a known, industrially mass-produceable manufacturing technique. So why can't nuclear fuel elements be made nano-sized...

[SOLVED] how many elements are in two power sets Homework Statement a.How many elements are in the power set {1,2,3,4}? b.How many elements are in the power set {1,2,3,4,5}? Homework Equations The Attempt at a Solution a. {empty set, {1}, {2}, {3}, {4}, {1,2}, {1,3}, {1,4}...

i'm a bit confused about the currents in the expression for a matrix element for an interaction... e.g. you could have a current like (adjoint spinor)x(spinor) which is scalar, this makes sense to me. or you could have a current like (adjoint spinor)x(gamma matrix)x(spinor) which is vector...

I have a question: it is generally stated that 100 micrometers is the acceptable limit on the thickness of the oxidation layer on Zircaloy4 fuel rods. But I'm at loss as what is the reason for this limit ? Is it structural integrity ? Thermal resistance ? Mechanical tolerance ?

Homework Statement How many subsets of a set with 100 elements have more than one element? The thing throwing me off here is the zero-set, and whether it counts as an element or that. Can someone start me off?

What is the proper way for me to write symbols for elements such as Chlorine?

So this sentence kind of confuses me: "On the other hand, if \alpha is a root of x^3 - x + 1, then \beta = \alpha^2 is a root of x^3 - 2x^2 + x - 1. The two fields Q(\alpha) and Q(\beta) are actually equal though if we were presented only with one of the two polynomials, it might take us some...

I hope some one can help with this. 2 different but identical rated elements are used for exactly the same purpose, the only difference between the 2 is, one has the element bent into three outer coils and three inner coils, the other has four outer coils and four inner coils, the one with...

Homework Statement If N is a normal subgroup of a group G and every element of N and G/N has finite order, prove that every element of G has finite order. Homework Equations Um, a finite group element is given such that g^k = e (identity) for some integer k. We also know that the...

Can someone list all the elements in each matrix of SO(3)? As opposed to the general definition of A^tA=1 with det(A)=1. In other words give the general form of all matrices in SO(3). This is usually done with SU(2) but haven't seen it with SO(3).

What r the superheavy elements? what do they do?any advantage or disadvantage?(please be specific) thnx!

Hi I am writing a program in Matlab and I want to search a string within a cell to identify where certain characters start and end. However, once I identify the start and end points I want to extract all the characters within that range. So for example let's say that I have a 25 row by 1...

Homework Statement Draw out the electron configuration of [Fe(H2O)6]3+ The Attempt at a Solution I did the work, but i am not sure if its correct: Is the following electron configuration correct for this complex? [Fe(H2O)6]3+: [Ar] 4s [ i L ] 3d [ i L l i L l i L l...

A group G has exactly 8 elements of order 3 (Unanswered as of 1/31) How many subgroups of order 3 does G have? So we have 8 elements, its prime decomposition is 8=2^3. The number of different ways to get factors is how many subgroups, at least that is what I interpret from my notes...so...

Let A be a set of n distinct elements. There is a one to one correspondence between binary relations on the set A and subsets R<= A x A a. Computer the number of binary realtions on A b. A binary relation R is said to be symmetric if for every (a,b) in R, (b,a) is also in R. Compute the...

Homework Statement What information can i find on the periodic table of the elements and what does it mean Homework Equations What is anything. The Attempt at a Solution Atomic symbol, the big letter, for the element abervation. The elements name, for the elements name. Atomic...

Homework Statement Let F be a finite field. Show that the product of all non-zero elements of F is -1. Homework Equations An example of this is Wilson's Theorem. The Attempt at a Solution Let G be the multiplicative group of non-zero elements of F. Then G is cyclic. Let a...

prove that if G is a finite and abelian group and m is the least common multiple of the order of it's element, that there is an element of order m. My idea: if ai are the elements of G, the order of a1*a2 is lcm(a1,a2) and the result follows directly when applied to all ai... but why is this...

Why there is on Earth stronger abundance of light elements. I mean elements that have proton number lower than 30. And are there any elements in nature in elemental(atomic) form?

Hi, everyone: I have been playing around with tensor products of vector spaces recently. This question came up: How can we tell if c(a(x)b)~(a(x)b) , or wether any two general elements are in the same class, other than in the std. cases like c(a(x)b)~(ca(x)v)~ (a(x)cv) ...

can anyone explain me the 1>significance 2>elements used to construct them 3>main usage to which industries of heat exchangers?

My understanding of analyzing emission spectra is that when the quantum number of an electron decreases (i.e. when it falls closer to the nucleus) it emits energy. I understand that this is a very basic understanding but I have not yet made it to college, so please bear with me. :) Now, what I...

Hello all Just a simple question that intrigue me recently. Some body could explain about how scientists exactly know that transuranium elements cannot be produced naturally in the Universe? JPAM

Hello, this is my first time posting... We're working on a cartoon for science class, and I was wondering if anyone knew the answer to a bit of a dilemma I have... If you take a single fragile, radioactive element and bond it with another fragile, radioactive element, is there a good...

Hi all, I'm trying to express a given requirement in a software system. I'm used to UML and UseCase specification, but I thought I would attempt to learn Zed Specification (which is based off logic, set theory., etc... so those topics too!) Given two sets of data e.g. in Zed notation...

As we have seen some mathematical sign lately in this group, because I put you in the drawing of the general sign of any element. You also can see more searching “from zero to infinite, ferman”. Thank you.

What research steps must be taken before we are able to convert hydrogen into carbon, oxygen, potassium, and so on? My quick estimate is that we may be able to do this with a particle accelerator and bombard hydrogen with neutrons and protons, with some massive amount of energy loss in the...

Homework Statement This is not HW per say, I'm just wondering what the elements of Alt_4 are (the subgroup of S4 consisting of all even permutations). I know Alt_4 is of order 4!/2=12, and I have so far that Id, (1 2 3), (1 2 4), (1 3 4), (2 3 4), (1 2)(3 4), (1 3)(2 4), (1 4)(2 3) are in...

which pair of elements is most apt to form an ionic compound with each other? nitrogen and hydrogen or barium and bromine? please explain

Forces between two current elements and Newton's third law Consider two non parallel wires each carrying a current which located at one plane surface. According to electromagnetic theory, the forces between two straight and solid wires mentioned can be estimated as follow: F= i . (L x B)...

Homework Statement Essentially the problem is to show that a certain finite group (specifically the special linear group of order 2 over the finite field of 3 elements) is generated by two elements. But the problem is that it's non-Abelian, so I can't just consider powers of the generators...

Ok so I just started taking this Bio 12 class after not being in High School for over 5 years! It is not what I thought it would be at all! Im kind of getting stuck on one topic and no matter who I talk to I still don't understand it. What is the dif between Atoms and Elements? I...

What does the electrical conductivity of the elements depends from?

1) If we have 5 letters: A, A, B, C, D, in how many ways (arrangements) can we form a 3-letter "word"? How can I calculate this? The 2 A's seem to make things very complicated...and I have no clue how to do it... It's arrangements, so I think permutation will be used. Also, there are...

Why do some elements, particularly the heavy ones, require melting for them to bond with other elements to create metals containing differing atoms? What role does temperature play in the form, conform, and inconform states of elements? And what role do the elements play in requiring...

Problem 1: The class of ternary compounds called carboranes (containing the elements carbon, boron and hydrogen) have played a prominent role in many areas of fundamental chemical research. In particular, they have provided many interesting examples for testing theories on chemical bonding...

Homework Statement If P(A) =0.4, P(B)=0.5, and P(A∪B)=0.7, find P(A’∪B’) The Attempt at a Solution P(A’) = (Probability of all elements in S that are not in A) = 1 - P(A) = 0.6 P(B’) = (Probability of all elements in S that are not in B) = 1 – P(B) = 0.5 P(A’∪B’)= The...

Homework Statement Prove that in any group the orders of ab and ba equal. Homework Equations n/a The Attempt at a Solution Let (ab)^{x} = 1. Using associativity, we get (ab)^{x} = a(ba)^{x-1}b = 1. Because of the existence of inverses--namely a^{-1} and b^{-1}--this implies (ba)^{x-1}...

Homework Statement Let G be a group with order \left| G \right| = 60. Assume that G is simple. Now let H be the set of all elements that can be written as a product of elements of order 5 in G. Show that H is a normal subgroup of G. Then conclude that H = G Homework Equations The...