From 83c1bfceb1b681b4bb7253b47491be2d8b2014a1 Mon Sep 17 00:00:00 2001
From: debashisdeb
Date: Fri, 20 Jun 2014 15:42:42 +0530
Subject: removing problem statements

---
 .../CH10.ipynb                                     | 10 -----
 .../CH12.ipynb                                     | 16 --------
 .../CH14.ipynb                                     | 24 ------------
 .../CH16.ipynb                                     | 15 --------
 .../CH17.ipynb                                     | 12 ------
 .../CH18.ipynb                                     | 33 ----------------
 .../CH19.ipynb                                     |  3 --
 .../CH20.ipynb                                     | 13 -------
 .../CH21.ipynb                                     |  8 ----
 .../CH3.ipynb                                      | 45 ----------------------
 .../CH4.ipynb                                      | 15 --------
 .../CH5.ipynb                                      | 26 -------------
 .../CH6.ipynb                                      | 33 ----------------
 .../CH7.ipynb                                      | 17 --------
 .../CH8.ipynb                                      | 11 ------
 .../CH9.ipynb                                      | 11 ------
 16 files changed, 292 deletions(-)

(limited to 'Materials_science_and_engineering_an_introduction')

diff --git a/Materials_science_and_engineering_an_introduction/CH10.ipynb b/Materials_science_and_engineering_an_introduction/CH10.ipynb
index 2a7a789c..b7fb2351 100644
--- a/Materials_science_and_engineering_an_introduction/CH10.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH10.ipynb
@@ -27,27 +27,21 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#(a)Computation of Critical Nuclear Radius\n",
       "\n",
-      "#Given\n",
       "Hf=-1.16*10**9     # in J/m**3  latent heat of fusion\n",
       "Y=0.132            # in J/m**2  Surface energy\n",
       "Tm=1064.0+273.0        # in K  Melting point of gold\n",
       "\n",
-      "#calculation\n",
       "import math\n",
       "T=Tm-230.0           # in K  230 is supercooling value\n",
       "r=-2*Y*Tm/(Hf*(Tm-T))\n",
       "G=16*math.pi*Y**3*Tm**2/(3*Hf**2*(Tm-T)**2)\n",
       "\n",
-      "#part (b)\n",
       "a=0.413*10**-9  # in m  Unit Cell edge length\n",
-      "#unit cells per paticle\n",
       "u_c=4*math.pi*r**3/(3*a**3)\n",
       "n=4            #In FCC . no of atoms in per unit cell\n",
       "U_c=int(u_c)*n\n",
       "\n",
-      "#Result\n",
       "print\"(a)Critical Radius is \",round(r/10**-9,2),\"nm\"\n",
       "print\"Activation free energy is \",round(G,21),\"J\"\n",
       "print\"(b)Total no. of atoms per critical nucleus are \",U_c\n",
@@ -80,19 +74,15 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Determination the rate of recrystallization\n",
       "\n",
-      "#Given\n",
       "n=5.0\n",
       "y=0.3\n",
       "t=100.0          #in min\n",
       "\n",
-      "#Calculation\n",
       "k=-math.log(1-y)/t**n\n",
       "thalf=(-math.log(1-0.5)/k)**(1/n)\n",
       "rate=1/thalf\n",
       "\n",
-      "#Result\n",
       "print\"Rate is \",rate,\"min**-1\"\n",
       "\n"
      ],
diff --git a/Materials_science_and_engineering_an_introduction/CH12.ipynb b/Materials_science_and_engineering_an_introduction/CH12.ipynb
index ee793447..b2774698 100644
--- a/Materials_science_and_engineering_an_introduction/CH12.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH12.ipynb
@@ -27,16 +27,12 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Computation of Minimum Caion-to-Anion Radius Ratio forCo-ordination No. of 3\n",
       "\n",
-      "#For equilateral triangle after joining centres of the atoms Angle = 30\n",
       "a=30\n",
       "\n",
-      "#Calculation\n",
       "import math\n",
       "ratio=(1-math.cos(a*math.pi/180.0))/math.cos(a*math.pi/180.0)\n",
       "\n",
-      "#Result\n",
       "print\"Cation to anion raio is \",round(ratio,3)\n",
       "\n"
      ],
@@ -65,16 +61,12 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Ceramic Crystal structure prediction\n",
       "\n",
-      "#Given\n",
       "r_Fe=0.077  # in nm Radius of iron cation Fe++\n",
       "r_O=0.140  #in nm  Radius of Oxygen anion O--\n",
       "\n",
-      "#Calculation\n",
       "ratio=r_Fe/r_O\n",
       "\n",
-      "#Result\n",
       "print\"Ratio is \",ratio\n",
       "if 0.414<ratio<0.732:  \n",
       "    print\"Co-ordinaton no. is 6\"\n",
@@ -110,22 +102,18 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Theoretical Density Determination for NaCl\n",
       "\n",
-      "#Given\n",
       "A_Na=22.99         # in g/mol\n",
       "A_Cl=35.45          #in g/mol\n",
       "r_Na=0.102*10**-7  #in cm Radius of Na+ ion\n",
       "r_Cl=0.181*10**-7  #in cm Radius of Cl- ion\n",
       "Na=6.023*10**23  #Avogadro number\n",
       "\n",
-      "#Calculation\n",
       "a=2*(r_Na+r_Cl)\n",
       "V=a**3\n",
       "n=4                 #For FCC, no. of atoms are 4 per crystal\n",
       "density=n*(A_Na+A_Cl)/(V*Na)\n",
       "\n",
-      "#Result\n",
       "print\"Density is \",round(density,2),\"gm/cm**3\"\n",
       "\n"
      ],
@@ -154,15 +142,12 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Computation of the No. of Schottky Defects in KCl\n",
       "\n",
-      "#Given\n",
       "Na=6.023*10**23   #Avogadro number\n",
       "density=1.955     #in g/cm**3\n",
       "A_K=39.1          #in g/mol\n",
       "A_Cl=35.45        #in g/mol\n",
       "\n",
-      "#calculation\n",
       "import math\n",
       "N=Na*density*10**6/(A_K+A_Cl)\n",
       "Qs=2.6           # in eV\n",
@@ -170,7 +155,6 @@
       "T=500.0+273.0        # in K\n",
       "Ns=N*math.exp(-Qs/(2*k*T))\n",
       "\n",
-      "#result\n",
       "print\"No. of Schottky Defects are \",round(Ns,-17),\"/m**3\"\n",
       "\n"
      ],
diff --git a/Materials_science_and_engineering_an_introduction/CH14.ipynb b/Materials_science_and_engineering_an_introduction/CH14.ipynb
index 7ade4dbe..e860f213 100644
--- a/Materials_science_and_engineering_an_introduction/CH14.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH14.ipynb
@@ -27,11 +27,7 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Computation of average Molecular wt and Degree of Polymerisation\n",
       "\n",
-      "#Given\n",
-      "#For different molecular wt range ,\n",
-      "#From Table 14.1 (a)\n",
       "Mi1=7500          #g/mol , Molecular wt\n",
       "Mi2=12500     \n",
       "Mi3=17500\n",
@@ -47,7 +43,6 @@
       "xi6=0.08\n",
       "xi7=0.02\n",
       "\n",
-      "#Calculation\n",
       "xM1=Mi1*xi1\n",
       "xM2=Mi2*xi2\n",
       "xM3=Mi3*xi3\n",
@@ -57,7 +52,6 @@
       "xM7=Mi7*xi7\n",
       "xM=xM1+xM2+xM3+xM4+xM5+xM6+xM7\n",
       "\n",
-      "#(b)\n",
       "nC=2          #no of carbon atoms in repeat unit\n",
       "nH=3          #no of hydrogen atoms in repeat unit\n",
       "nCl=1         #no of chlorine atoms in repeat unit\n",
@@ -67,7 +61,6 @@
       "m=nC*MwC+nH*MwH+nCl*MwCl     #Total wt for PVC\n",
       "DP=xM/m\n",
       "\n",
-      "#(c) from fig 14.3 (b)\n",
       "wi1=0.02           #weight fraction\n",
       "wi2=0.1\n",
       "wi3=0.18\n",
@@ -76,7 +69,6 @@
       "wi6=0.13\n",
       "wi7=0.02\n",
       "\n",
-      "#Calculation\n",
       "wM1=Mi1*wi1\n",
       "wM2=Mi2*wi2\n",
       "wM3=Mi3*wi3\n",
@@ -86,7 +78,6 @@
       "wM7=Mi7*wi7\n",
       "wM=wM1+wM2+wM3+wM4+wM5+wM6+wM7\n",
       "\n",
-      "#Result\n",
       "print\"(a)The no Av Molecular wt is\",xM,\"g/mol\"\n",
       "print\"(b)Degree of Polymerisation is\",round(DP,0)\n",
       "print\"(c)The weight  Av Molecular wt is\",wM,\"g/mol\"\n"
@@ -118,9 +109,7 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Computations of the Density\n",
       "\n",
-      "#Given\n",
       "Ac=12.01       #in g/mol  Molecular weight of Carbon\n",
       "Ah=1.008       #in g/mol  molecular weight of hydrogen\n",
       "a=7.41*10**-8  #in cm\n",
@@ -128,18 +117,15 @@
       "c=2.55*10**-8  #in cm\n",
       "Na=6.023*10**23\n",
       "\n",
-      "#calculation\n",
       "Vc=a*b*c\n",
       "n=2\n",
       "A=(2*Ac)+(4*Ah)\n",
       "density_c=n*A/(Vc*Na)\n",
       "\n",
-      "#(b)Percent Crystallinity of Polyethylene\n",
       "density_a=0.870  # in g/cm**3\n",
       "density_s=0.925  # in g/cm**3\n",
       "pc=density_c*(density_s-density_a)*100/(density_s*(density_c-density_a))\n",
       "\n",
-      "#Result\n",
       "print\"(a)Density is\",round(density_c,3),\"g/cm**3\"\n",
       "print\"(b)percentage crystallinity is\",round(pc,1),\"%\"\n",
       "\n"
@@ -170,31 +156,21 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Computations of Diffusion Flux of Carbon dioxide through Plasic Beverage Container\n",
       "\n",
-      "#function[A]= approx(V,n)\n",
-      "#    A= round(V*10**n)/10**n\n",
-      "#    funcprot(0)\n",
-      "#endfunction\n",
       "\n",
-      "#print\"\\tExample 14.3\\n\")\n",
       "\n",
-      "#a\n",
       "P1=400000.0       # in Pa  Pressure inside the bottle\n",
       "P2=400.0          # in Pa  Pressure outside the bottle\n",
       "Pm=0.23*10**-13  #Solubility Coefficient\n",
       "dx=0.05          # in cm Thickness of wall\n",
       "\n",
-      "#calculation\n",
       "J=(-Pm*(P2-P1)/dx)\n",
-      "#(b)Beverage Shell Life\n",
       "\n",
       "A=500           #surface area of bottle in cm**2\n",
       "V_lose=750.0    #cm**3 STP\n",
       "V=J*A\n",
       "t=V_lose/round(V,5)\n",
       "\n",
-      "#Result\n",
       "print\"Diffusion flux is \",round(J,9),\"cm**3 STP/cm**2-s\"\n",
       "print\"Time to escape is \",round(t/(3600*24),1),\"days\"\n",
       "\n"
diff --git a/Materials_science_and_engineering_an_introduction/CH16.ipynb b/Materials_science_and_engineering_an_introduction/CH16.ipynb
index c360c16f..02f6165f 100644
--- a/Materials_science_and_engineering_an_introduction/CH16.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH16.ipynb
@@ -27,17 +27,12 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#(a) Compute the modulus of elasticity\n",
-      "#(b)  find Load carried by each of fiber and matrix phase\n",
-      "#(c) Determine the strain\n",
       "\n",
-      "#Given\n",
       "E_gf=69.0     # in GPa  Elasticity of glass fibre\n",
       "mf_gf=0.4     #Vol % of glass fibre\n",
       "E_pr=3.4      # in GPa  Elasticity of poyester resin\n",
       "mf_pr=0.6     #Vol % of polyester resin\n",
       "\n",
-      "#Calculation\n",
       "E_cl=(E_pr*mf_pr)+(E_gf*mf_gf)\n",
       "Ac=250.0         #mm**2\n",
       "sigma=50.0       #MPa\n",
@@ -52,7 +47,6 @@
       "e_m=sigma_m/(E_pr*10**3)  #Strain for matrix phase\n",
       "e_f=sigma_f/(E_gf*10**3)  #Strain for fiber phase\n",
       "\n",
-      "#Result\n",
       "print\"(a)Modulus of elasticity of composite is \",round(E_cl,0),\"GPa\"\n",
       "print\"(b)Load carried by each of fiber and matrix phase is \",round(Ff,0),\"N\"\n",
       "print\"(c)Strain for matrix phase is \",round(e_m,4)\n",
@@ -87,18 +81,14 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Elastic Modulus Determination for a Glass Fiber-Reinforced Composite\u2014Transverse Direction\n",
       "\n",
-      "#Given\n",
       "E_gf=69      # in GPa  Elasticity of glass fibre\n",
       "mf_gf=0.4    #Vol % of glass fibre\n",
       "E_pr=3.4     # in GPa  Elasticity of poyester resin\n",
       "mf_pr=0.6    #Vol % of polyester resin\n",
       "\n",
-      "#Calculation\n",
       "E_ct=E_pr*E_gf/((E_pr*mf_gf)+(E_gf*mf_pr))  #GPa\n",
       "\n",
-      "#Result\n",
       "print\"In transverse direction, modulus of elaticity is \",round(E_ct,1),\"GPa\"\n",
       "\n"
      ],
@@ -127,21 +117,16 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#A tubular composite shaft is to be designed.\n",
       "\n",
-      "#Given\n",
       "Do=70*10**-3        #mm, outside diameter\n",
       "Di=50*10**-3        #mm, inside diameter\n",
       "L=1                 #m Length\n",
       "F=1000              #N load\n",
       "dy=0.35*10**-3      #mm, deflection\n",
       "\n",
-      "#Calculation\n",
-      "#Required longitudinal modulus of elasticity\n",
       "E=(4*F*L**3)/(3*math.pi*dy*(Do**4-Di**4))\n",
       "Vc=(math.pi*L*(Do**2-Di**2))/4.0\n",
       "\n",
-      "#Result\n",
       "print\"(a)longitudinal modulus of elasticity is\",round(E/10**9,1),\"GPa\"\n",
       "print\"(b)The total tube volume is\",round(Vc*10**6,0),\"cm**3\"\n"
      ],
diff --git a/Materials_science_and_engineering_an_introduction/CH17.ipynb b/Materials_science_and_engineering_an_introduction/CH17.ipynb
index 294f5ff9..889d524a 100644
--- a/Materials_science_and_engineering_an_introduction/CH17.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH17.ipynb
@@ -27,20 +27,16 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Determination of Electrochemical Cell Characteristics\n",
       "\n",
-      "#Given\n",
       "V_Cd=-0.403  #Half Cell Potential of Cd++|Cd\n",
       "V_Ni=-0.250  #Half Cell Potential of Ni++|Ni\n",
       "\n",
-      "#calculation\n",
       "dV=V_Ni-V_Cd\n",
       "C_Ni=10**-3\n",
       "C_Cd=0.5\n",
       "n=2          #Net electron exchange in Redox reaction\n",
       "V=-dV-(0.0592*math.log10(C_Ni/C_Cd)/n)\n",
       "\n",
-      "#Result\n",
       "print\"Standard Cell potential is \",dV,\"V\"\n",
       "print\"Net EMF is \",round(V,3),\"V\"\n",
       "if V<0:\n",
@@ -77,28 +73,20 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Rate of Oxidation Computation\n",
       "\n",
-      "#Given\n",
-      "#Activation polarisation data for Zn\n",
       "VZn_Zn2=-0.763\n",
       "iZn=10**-7\n",
       "beta_Zn=0.09\n",
-      "#For H2\n",
       "iH2=10**-10\n",
       "VH_H2=0\n",
       "beta_H2=-0.08\n",
       "\n",
-      "#calculation\n",
-      "#Part i\n",
       "ic=10**((VH_H2-VZn_Zn2-(beta_H2*math.log10(iH2))+(beta_Zn*math.log10(iZn)))/(beta_Zn-beta_H2))\n",
       "n=2              #Exchange of 2 electrons\n",
       "F=96500          #Faradays constant\n",
       "r=ic/(n*F)\n",
-      "#Part ii\n",
       "Vc=VH_H2+(beta_H2*log10(ic/iH2))\n",
       "\n",
-      "#Result\n",
       "print\"i) Rate of oxiadation is\",round(r,12),\"mol/cm**2-s\"\n",
       "print\"ii) Corrosion potential is\",round(Vc,3),\"V\"\n",
       "\n"
diff --git a/Materials_science_and_engineering_an_introduction/CH18.ipynb b/Materials_science_and_engineering_an_introduction/CH18.ipynb
index 016bfd26..cae50c36 100644
--- a/Materials_science_and_engineering_an_introduction/CH18.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH18.ipynb
@@ -27,16 +27,12 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Computation of the Room-Temperature Intrinsic Carrier Concentration for Gallium Arsenide\n",
       "\n",
-      "#Given\n",
       "sigma=10**-6   # (Ohm-m)**-1  Electrical Conductivity\n",
       "e=1.6*10**-19  #Coulomb Charge on electron\n",
       "m_e=0.85       # m**2/V-s  Mobility of electron\n",
       "m_h=0.04       # m**2/V-s  Mobility of holes\n",
       "\n",
-      "#Calculation\n",
-      "#ni is Intrinsic carrier concentration\n",
       "ni=sigma/(e*(m_e+m_h))\n",
       "\n",
       "print\"Intrinsic Carrier Concentration is\",round(ni,-11),\"m**-3\"\n",
@@ -67,20 +63,14 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Electrical Conductivity Determination for Intrinsic Silicon at 150\u00b0C\n",
       "\n",
-      "#Given\n",
       "e=1.6*10**-19    #Coulomb Charge on electron\n",
       "ni=4*10**19      #For Si at 423 K   (m**-3)\n",
-      "#Values of m_e and m_h are deduced from graphs at page No.689\n",
       "m_e=0.06        #m**2/V-s  Mobility of electron\n",
       "m_h=0.022       #m**2/V-s  Mobility of holes\n",
       "\n",
-      "#calculation\n",
-      "#sigma is electrical conductivity\n",
       "sigma=ni*e*(m_e+m_h)\n",
       "\n",
-      "#result\n",
       "print\"Electrical Conductivity is \",round(sigma,2),\"(ohm-m)**-1\"\n",
       "\n"
      ],
@@ -109,25 +99,17 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Room-Temperature for Extrinsic Silicon\n",
       "\n",
-      "#Given (b)\n",
       "n=10**23 #m**-3  Carrier Concentration\n",
       "e=1.6*10**-19  #Coulomb  Charge on electron\n",
-      "#From graph 18.18 m_e is calculated corresponding to n=10**23\n",
       "m_e=0.07  #m**2/V-s  Mobility of electron\n",
       "\n",
-      "#Calculation\n",
-      "#For extrinsic n-type, the formula used is:\n",
       "sigma=n*e*m_e\n",
       "\n",
       "\n",
-      "#(c)Elevated-Temperature Electrical Conductivity Calculations for Extrinsic Silicon\n",
-      "#From graph 18.19a m_e2 is calculated corresponding to 373 K\n",
       "m_e2=0.04  #m**2/V-s  Mobility of electron\n",
       "sigma2=n*e*m_e2\n",
       "\n",
-      "#Result\n",
       "print\"Conductivity at n=10**23 is \",sigma,\"(Ohm-m)**-1\"\n",
       "print\"Conductivity at T=373 K becomes \",sigma2,\"(Ohm-m)**-1\"\n",
       "\n"
@@ -158,30 +140,23 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Specify an impurity acceptor  type\n",
       "\n",
-      "#Given\n",
       "c=50           #ohm**-1, room temprature conductivity\n",
       "Na1=10**22      #m**-3, assumed impurity content value\n",
       "mu1=0.04        #m**2/Vs, assumed electrical mobility\n",
       "e=1.6*10**-19  #Electronic charge\n",
       "NA=6.023*10**23     #Avagadro no\n",
       "\n",
-      "#Calculation\n",
       "C=Na1*e*mu1    #Conductivity\n",
-      "#Decreasing  an impurity content\n",
       "Na2=10**21      #m**-3, \n",
       "mu2=0.045       #m**2/Vs,\n",
       "C=Na2*e*mu2\n",
-      "#So we get conductivity = 50 at\n",
       "Na=8*10**21 \n",
-      "#For Silicon\n",
       "rho=2.33       # g/cm**3\n",
       "Asi=28.09      # g/mole\n",
       "Nsi=(NA*rho*10**6)/(Asi)\n",
       "Ca=(Na/(Na+Nsi))*100\n",
       "\n",
-      "#Result\n",
       "print\"The concentration of acceptor impurities is\",round(Ca,7)\n",
       "print\"Thus a Silicon material having conductivity 50 ohm**-1  \\nmust contain\",round(Ca,7),\"% boron,aluminium,Gallium or indium .\"\n"
      ],
@@ -212,9 +187,7 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Hall Voltage Computation\n",
       "\n",
-      "#Given\n",
       "sigma=3.8*10**7  #(Ohm-m)**-1  Electrical Conductivity\n",
       "m_e=0.0012       #m**2/V-s  Mobility of electron\n",
       "Rh=-m_e/sigma    #Hall coefficient\n",
@@ -222,10 +195,8 @@
       "d=15*10**-3      #m Thickness\n",
       "Bz=0.6           #Tesla  Magnetic field\n",
       "\n",
-      "#Calculation\n",
       "Vh=Rh*Ix*Bz/d\n",
       "\n",
-      "#Result\n",
       "print\"Hall coefficient is \",round(Rh,13),\"V-m/A-Tesla\"\n",
       "print\"Hall Voltage is \",round(Vh,10),\"V\"\n",
       "\n"
@@ -256,22 +227,18 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#find the Capacitance \n",
       "\n",
-      "#Given\n",
       "A=6.45*10**-4    #m**2, area\n",
       "d=2*10**-3       #m. Plate separation\n",
       "V=10             #V Potential\n",
       "Er=6             #Dielectric constant\n",
       "Eo=8.85*10**-12  #F/m  Constant dielectric constant\n",
-      "#Calculation\n",
       "E=Er*Eo\n",
       "C=E*A/d\n",
       "Q=C*V\n",
       "D=E*V/d\n",
       "P=D-Eo*V/d\n",
       "\n",
-      "#Result\n",
       "print\"The Capacitance is\",round(C,13),\"F\"\n",
       "print\"The magnitude of charge stored is \",round(Q,12),\"C\"\n",
       "print\"The Dielectric displacement is is\",round(D,9),\"C/m**2\"\n",
diff --git a/Materials_science_and_engineering_an_introduction/CH19.ipynb b/Materials_science_and_engineering_an_introduction/CH19.ipynb
index 8464a899..1da6512a 100644
--- a/Materials_science_and_engineering_an_introduction/CH19.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH19.ipynb
@@ -27,15 +27,12 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "# Calculation of maximum temperature\n",
       "\n",
-      "#Given\n",
       "To=20         # Room Temperature (degree celsius)\n",
       "sigma=-172    #Mpa  Compressive stress\n",
       "E=100*10**3   #Mpa Young's modulus\n",
       "a=20*10**-6   #Celsius**-1  Coefficient of thermal expansion\n",
       "\n",
-      "#Calculation\n",
       "Tf=To-(sigma/(E*a))\n",
       "\n",
       "print\"Final Temperature is \",Tf,\"C\"\n",
diff --git a/Materials_science_and_engineering_an_introduction/CH20.ipynb b/Materials_science_and_engineering_an_introduction/CH20.ipynb
index c410a6ac..b3d2e8d5 100644
--- a/Materials_science_and_engineering_an_introduction/CH20.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH20.ipynb
@@ -27,9 +27,7 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "# Calculation of saturation magnetisation and flux density for Nickel\n",
       "\n",
-      "#Given\n",
       "b_m=9.27*10**-24   #ampere*m**2  (Bohr Magneton)\n",
       "Na=6.023*10**23    #atoms/mol  (Avogadro's No.)\n",
       "d=8.9*10**6        #g/m**3   (density)\n",
@@ -37,13 +35,9 @@
       "A=58.71             #g/mol  (Atomic weigth of Nickel)\n",
       "N=d*Na/A            #No. of atoms per cubic meter\n",
       "\n",
-      "#Calculation\n",
-      "# M is saturation magnetisation\n",
       "M=0.6*b_m*N  #0.6= Bohr Magneton/atom\n",
-      "#B = Saturation Flux Density\n",
       "B=uo*M\n",
       "\n",
-      "#Result\n",
       "print\"Saturation Magnetisation is \",M,\"A/m\"\n",
       "print\"Saturation Flux Density is \",round(B,2),\"Tesla\"\n"
      ],
@@ -73,14 +67,11 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "# Calculation of saturation magnetisation of Fe3O4\n",
       "\n",
-      "#Given\n",
       "a=0.839*10**-9   #a is edge length in m\n",
       "b_m=9.27*10**-24 #ampere*m**2  (Bohr Magneton)\n",
       "nb=8*4           #8 is no. of Fe++ ions per unit cell\n",
       "                 #4 is Bohr magnetons per Fe++ ion\n",
-      "#Calculation\n",
       "M=nb*b_m/a**3  #M is Saturation magnetisation\n",
       "\n",
       "print\"Saturation Magnetisation is \",round(M,0),\"A/m\"\n",
@@ -111,21 +102,17 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Design Example 20.1: Designing a cubic mixed-ferrite magnetic material\n",
       "\n",
-      "#Given\n",
       "Ms_Fe=5.25*10**5   #Required saturation Magnetisation\n",
       "b_m=9.27*10**-24   #ampere*m**2  (Bohr Magneton)\n",
       "a=0.839*10**-9     #a is edge length in m\n",
       "M=5*10**5          #From previous question result\n",
       "\n",
-      "#Calculation\n",
       "nb=Ms_Fe*a**3/b_m\n",
       "i=8             # No of Divalent ions per unit cell\n",
       "j=4             #4 is Bohr magnetons per Mn++ ion\n",
       "n=nb/(i)-j \n",
       "         \n",
-      "#Result\n",
       "print\"Replacing percent of Fe++ with Mn++ would produce the required saturation magnetisation\",round(n*100,2)\n",
       "\n"
      ],
diff --git a/Materials_science_and_engineering_an_introduction/CH21.ipynb b/Materials_science_and_engineering_an_introduction/CH21.ipynb
index bb8267f6..38c06f2e 100644
--- a/Materials_science_and_engineering_an_introduction/CH21.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH21.ipynb
@@ -27,20 +27,12 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "# Calculation of absorption coefficient\n",
       "\n",
-      "#Given\n",
-      "# x is thickness of glass(mm)\n",
       "x=200\n",
-      "#It is intensity of non-absorbed radiation\n",
-      "#Io is intensity of non-relected radiation\n",
       "f=0.98  #f=It/Io\n",
       "\n",
-      "#Calculation\n",
-      "#b is absorption coefficient\n",
       "b=-math.log(f)/x\n",
       "\n",
-      "#result\n",
       "print\"Absorption coefficient is \",round(b,4),\"mm**-1\"\n",
       "\n"
      ],
diff --git a/Materials_science_and_engineering_an_introduction/CH3.ipynb b/Materials_science_and_engineering_an_introduction/CH3.ipynb
index c521d51b..eeb7447f 100644
--- a/Materials_science_and_engineering_an_introduction/CH3.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH3.ipynb
@@ -27,20 +27,13 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Determination of FCC Unit Cell Volume\n",
       "\n",
-      "#Given\n",
-      "#For FCC a=2*R*math.sqrt(2)\n",
       "from sympy import Symbol\n",
       "\n",
-      "#Calculation \n",
       "R=Symbol('R')   \n",
-      "#Edge Length\n",
       "a=2*R*round(math.sqrt(2),2)\n",
-      "#Volume determination\n",
       "V=a**3\n",
       "\n",
-      "#result\n",
       "print\"Volume is\",V,\"  m**3\"\n",
       "print\"which is also equal to 16*sqrt(2)*R**3\"\n",
       "\n"
@@ -71,25 +64,15 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Computation of the Atomic Packing Factor for FCC\n",
       "\n",
-      "#Given\n",
-      "#for FCC no. of atoms are 4\n",
       "n=4\n",
-      "#For FCC a=2*R*math.sqrt(2)\n",
       "R=1        #say\n",
       "\n",
-      "#Calculation\n",
-      "#Edge Length\n",
       "a=2*R*math.sqrt(2)\n",
-      "#Volume determination of cube\n",
       "Vc=a**3\n",
-      "#Volume of sphere\n",
       "Vs=n*4*math.pi*R**3/3.0\n",
-      "#Atomic packing Fraction\n",
       "APF=Vs/Vc\n",
       "\n",
-      "#Result\n",
       "print\"Atomic packing fraction is\",round(APF,2)\n",
       "\n"
      ],
@@ -118,20 +101,16 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Theoretical Density Computation for Copper\n",
       "\n",
-      "#Given\n",
       "R=1.28*10**-8        #Atomic radius in cm\n",
       "A_Cu=63.5            #Atomic wt of copper\n",
       "n=4                  #For FCC\n",
       "Na=6.023*10**23       #Avogadro no.\n",
       "\n",
-      "#Calculation\n",
       "a=2*R*math.sqrt(2)\n",
       "Vc=a**3\n",
       "den=n*A_Cu/(Vc*Na)\n",
       "\n",
-      "#result\n",
       "print\"Density is  \",round(den,2),\"g/cm**3\"\n"
      ],
      "language": "python",
@@ -159,17 +138,13 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Determination of Directional Indices\n",
       "\n",
-      "#Given\n",
-      "#Projection of given vector\n",
       "a=1/2.0\n",
       "b=1\n",
       "c=0\n",
       "\n",
       "x=[2*a,2*b,2*c]\n",
       "\n",
-      "#Result\n",
       "print\"The intercept for the given plane is\",x\n",
       "\n"
      ],
@@ -198,16 +173,11 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Determination of Directional Indices for a Hexagonal Unit Cell\n",
       "\n",
-      "#Given\n",
-      "#Projection in terms of unit cell parameter\n",
       "du=1\n",
       "dv=1\n",
       "dw=1\n",
       "\n",
-      "#Calculation\n",
-      "#For hexagonal system\n",
       "u=(2*du-dv)/3.0\n",
       "v=(2*dv-du)/3.0\n",
       "t=-(u+v)\n",
@@ -242,21 +212,16 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Determination of Planar (Miller) Indices\n",
       "\n",
-      "#Given\n",
       "a=-1\n",
       "b=1/2.0\n",
       "\n",
       "\n",
-      "#Calculation\n",
-      "#Reciprocal\n",
       "l=0      #Reciprocal of infinity\n",
       "m=1/a\n",
       "n=1/b\n",
       "x=[l,m,n]\n",
       "\n",
-      "#Result\n",
       "print\"The intercept for the given plane is\",x\n"
      ],
      "language": "python",
@@ -284,18 +249,14 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Determination of Miller\u2013Bravais Indices for a Plane Within a Hexagonal Unit Cell\n",
       "\n",
-      "#Intersection in terms of lattics Parameters\n",
       "h=1        #Reciprocal of intersection point\n",
       "k=-1\n",
       "l=1\n",
       "i=-(h+k)\n",
       "\n",
-      "#Calculation\n",
       "x=[h,k,i,l]\n",
       "\n",
-      "#Result\n",
       "print\"The indices of plane are\",x\n",
       "\n"
      ],
@@ -324,25 +285,19 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Interplanar Spacing\n",
       "\n",
-      "#Given\n",
       "a=0.2866           #Lattice parameter in nm\n",
       "h=2\n",
       "k=2\n",
       "l=0\n",
       "\n",
-      "#Calculation\n",
       "import math\n",
-      "#(a)\n",
       "d_hkl=a/(math.sqrt(h**2+k**2+l**2))\n",
       "\n",
-      "#(b)Diffraction Angle Computations\n",
       "lam=0.1790     #Wavelength in nm\n",
       "n=1\n",
       "theta=math.asin(n*lam/(2*d_hkl))\n",
       "\n",
-      "#Result\n",
       "print\"(a)Interplanar spacing is  \",round(d_hkl,4),\"nm\"\n",
       "print\"(b)Diffraction angle is  \",round(2*theta*(180/math.pi),1),\"degree\"\n",
       "\n"
diff --git a/Materials_science_and_engineering_an_introduction/CH4.ipynb b/Materials_science_and_engineering_an_introduction/CH4.ipynb
index 93bc9a2e..253ffd46 100644
--- a/Materials_science_and_engineering_an_introduction/CH4.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH4.ipynb
@@ -27,23 +27,17 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Number of Vacancies Computation at a Specified temperature\n",
       "\n",
-      "#Given\n",
       "Na=6.023*10**23      #Avogadro No.\n",
       "den=8.4*10**6        #Density of Copper\n",
       "A=63.5              #Atomic weight of Copper\n",
       "\n",
-      "#Calculation\n",
-      "#No. of atomic site per cubic meter\n",
       "N=Na*den/A\n",
-      "#No. of vacancies at 1000 C\n",
       "Qv=0.9                 #Activation energy in eV\n",
       "k=8.62*10**-5          # Boltzmann Constatnt in eV/K\n",
       "T=1000.0+273.0         #Temperature in K\n",
       "Nv=N*exp(-Qv/(k*T))\n",
       "\n",
-      "#Result\n",
       "print\"No.of vacancies are \",round(Nv,-24),\"/m**3\"\n",
       "\n"
      ],
@@ -72,10 +66,7 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Composition Conversion- From weight percent to Atom percent\n",
       "\n",
-      "#Given\n",
-      "#Conversion to Atom percent\n",
       "C_Al=97.0       #Aluminium wt%\n",
       "C_Cu=3.0        #Copper wt%\n",
       "A_Al=26.98      #Atomic wt of Aluminium\n",
@@ -114,20 +105,14 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Computations of ASTM Grain Size Number\n",
       "\n",
-      "#Given\n",
       "N=45.0           #No. of grains per square inch\n",
       "\n",
-      "#Calculation\n",
-      "#Dterminin grain size no.  N=2**(n-1)\n",
       "n=(math.log(N)/math.log(2))+1\n",
       "\n",
-      "#Number of Grains Per Unit Area\n",
       "M=85.0\n",
       "Nm=(100/M)**2*2**(n-1)\n",
       "\n",
-      "#Result\n",
       "print\"Grain size no. is \",round(n,1)\n",
       "print\"No. of grains per inch square are \",round(Nm,1)\n",
       "\n"
diff --git a/Materials_science_and_engineering_an_introduction/CH5.ipynb b/Materials_science_and_engineering_an_introduction/CH5.ipynb
index 5b193d64..caf36165 100644
--- a/Materials_science_and_engineering_an_introduction/CH5.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH5.ipynb
@@ -27,19 +27,15 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Diffusion Flux Computation\n",
       "\n",
-      "#Given\n",
       "Ca=1.2       #Concentration at A in  kg/m**3\n",
       "Cb=0.8       #Concentration at B in  kg/m**3\n",
       "xa=5*10**-3   #Position 1 in m\n",
       "xb=10*10**-3  #Position 2 in m\n",
       "\n",
-      "#Calculation\n",
       "D=3*10**-11   #Diffusion coefficient in m**2/s\n",
       "J=-D*(Ca-Cb)/(xa-xb)\n",
       "\n",
-      "#Result\n",
       "print\"Diffusion flux is \",J,\"kg/m**2-s\"\n",
       "\n"
      ],
@@ -68,16 +64,13 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Nonsteady-State Diffusion Time Computation I\n",
       "from scipy.optimize import fsolve\n",
-      "#Given\n",
       "Co=0.25        #Initial Conc. in wt%\n",
       "Cs=1.2         #Surface conc. in wt%\n",
       "Cx=0.8         #Conc. at any x  in wt%\n",
       "x=5*10**-4     #Position in m\n",
       "D=1.6*10**-11  #Diffusion coeff in m**2/s\n",
       "\n",
-      "#Calculation\n",
       "import math\n",
       "C=1-((Cx-Co)/(Cs-Co))\n",
       "\n",
@@ -86,7 +79,6 @@
       "z=fsolve(f,1)\n",
       "t=x**2/(4.0*D*z**2.0)\n",
       "\n",
-      "#Result\n",
       "print\"Time required is \",round(t/3600.0,1),\"h\"\n",
       "\n"
      ],
@@ -115,17 +107,13 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Nonsteady-State Diffusion Time Computation II\n",
       "\n",
-      "#Given\n",
       "D500=4.8*10**-14     #Diffusion coefficient at 500 C\n",
       "D600=5.3*10**-13     #Diffusion coefficient at 600 C\n",
       "t600=10             #Time in hours to diffuse\n",
       "\n",
-      "#Calcuation\n",
       "t500=D600*t600/D500\n",
       "\n",
-      "#Result\n",
       "print\"Time to diffuse at 500 C is \",round(t500,1),\"h\"\n",
       "\n"
      ],
@@ -154,19 +142,15 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Diffusion Coefficient Determination\n",
       "\n",
-      "#Given\n",
       "T=550+273            #in K\n",
       "D0=1.2*10**-4        #Temperature independent preexponential in m**2/s\n",
       "Qd=131000            #Activation energy in J/mol-K\n",
       "R=8.31               #Universal Gas constt\n",
       "\n",
-      "#Calculation\n",
       "import math\n",
       "D=D0*math.exp(-Qd/(R*T))\n",
       "\n",
-      "#Result\n",
       "print\"Diffusion coefficient is \",round(D,14),\"m**2/s\"\n",
       "\n"
      ],
@@ -195,21 +179,16 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Diffusion Coefficient Activation Energy and Preexponential Calculations\n",
       "\n",
-      "#Given\n",
-      "#From graph log D ad 1/T are deducted\n",
       "inv_T1=0.8*10**-3          #Reciprocal of temp.  in K**-1\n",
       "inv_T2=1.1*10**-3          #Reciprocal of temp.  in K**-1\n",
       "logD1=-12.4\n",
       "logD2=-15.45\n",
       "R=8.31                   #Gas law Constant in J/mol-K\n",
       "\n",
-      "#Calculation\n",
       "Qd=-2.3*R*(logD1-logD2)/(inv_T1-inv_T2)\n",
       "print\"Activation energy is\",round(Qd/1000,0),\"KJ\"\n",
       "\n",
-      "#For calculating Peexponential factor\n",
       "D0=10**(logD2+(Qd*inv_T2/(2.3*R)))\n",
       "print\"Preexponential factor is\",round(D0,6),\"m**2/s\"\n",
       "\n"
@@ -240,9 +219,7 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Diffusion Temperature\u2013Time Heat Treatment Specification\n",
       "\n",
-      "#Given\n",
       "C0=0.2           #Initial concentration in wt%\n",
       "Cs=1             #Surface conc in wt%\n",
       "Cx=0.6           #Conc at any position X in wt%\n",
@@ -255,10 +232,8 @@
       "z=0.4747\n",
       "Dt=(x/(2*z))**2\n",
       "\n",
-      "#Dt=D0*exp(-Qd/RT)*t = value of variable Dt\n",
       "D=Dt/D0\n",
       "\n",
-      "#The tempratures are\n",
       "T1=900.0\n",
       "T2=950.0\n",
       "T3=1000.0\n",
@@ -268,7 +243,6 @@
       "t3=D/math.exp(-Qd/(R*(T3+273)))/3600.0\n",
       "t4=D/math.exp(-Qd/(R*(T4+273)))/3600.0\n",
       "\n",
-      "#Result\n",
       "print\"Temperature in Celcius  are\",T1,T2,T3,T4\n",
       "print\"Time is respectively \",round(t1,1),\"h,\",round(t2,1),\"h,\",round(t3,1),\"h,\",round(t4,1),\"h\"\n",
       "\n"
diff --git a/Materials_science_and_engineering_an_introduction/CH6.ipynb b/Materials_science_and_engineering_an_introduction/CH6.ipynb
index e04ca9e8..490f5d5d 100644
--- a/Materials_science_and_engineering_an_introduction/CH6.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH6.ipynb
@@ -27,17 +27,13 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Elongation (Elastic) Computation\n",
       "\n",
       "E=110*10**3  #Young's modulus of Copper in MPa\n",
       "sigma=276.0    #Applied stress in MPa\n",
       "lo=305.0       #Original length in mm\n",
       "\n",
-      "#Calculation\n",
-      "#Deformation\n",
       "dl=sigma*lo/E\n",
       "\n",
-      "#Result\n",
       "print\"Elongation obtained is  \",round(dl,2),\"mm\"\n",
       "\n"
      ],
@@ -66,21 +62,17 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Computation of Load to Produce Specified Diameter Change\n",
       "\n",
-      "#Given\n",
       "del_d=-2.5*10**-3  #Deformation in dia  in mm\n",
       "d0=10.0             #Initial dia  in mm\n",
       "v=0.34           #Poisson ratio for brass\n",
       "\n",
-      "#Calculation\n",
       "ex=del_d/d0\n",
       "ez=-ex/v\n",
       "E=97*10**3        #Modulus of elasticity in MPa\n",
       "sigma=ez*E\n",
       "F=sigma*math.pi*(d0**2)/4.0\n",
       "\n",
-      "#Result\n",
       "print\"Applied force is \",round(F,0),\"N\"\n",
       "\n"
      ],
@@ -109,30 +101,22 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#From draph in the question\n",
-      "#stress and strain can be obtained\n",
       "\n",
-      "#Given\n",
       "si2=150           # in MPa\n",
       "si1=0\n",
       "e2=0.0016\n",
       "e1=0\n",
       "d0=12.8*10**-3    #Initial Diameter in m\n",
       "\n",
-      "#Calculation\n",
-      "#(a)Young's Modulus = stress/strain\n",
       "E=(si2-si1)/(e2-e1)\n",
       "\n",
       "A0=math.pi*d0**2/4.0\n",
       "sig=450*10**6     #tensile strength in MPa\n",
       "F=sig*A0\n",
-      "#From stress-strain curve\n",
-      "#Strain corresponding to stress of 345 MPa is 0.06\n",
       "l0=250     #Initial lengt in mm\n",
       "e=0.06     #strain\n",
       "dl=e*l0\n",
       "\n",
-      "#Result\n",
       "print\"Modulus of elasticity is \",round(E/10**3,1),\"GPa\"\n",
       "print\"From the graph the Yield strength is\",l0,\"MPa\"\n",
       "print\"Maximum load sustained is \",round(F,0),\"N/n\"\n",
@@ -168,17 +152,12 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Ductility\n",
       "\n",
-      "#Given\n",
       "di=12.8     #Initial dia in mm\n",
       "df=10.7     #Final dia  in mm\n",
       "\n",
-      "#Calculation\n",
       "import math\n",
-      "#Ductility in terms of Reduction Area \n",
       "RA = ((di**2-df**2)/di**2)*100\n",
-      "#True-Stress-At-Fracture Computations\n",
       "Ao=math.pi*di**2*10**-6/4.0\n",
       "sig=460*10**6    #Tensile strength\n",
       "\n",
@@ -187,7 +166,6 @@
       "Af=math.pi*df**2/4.0\n",
       "sig_t=F/Af\n",
       "\n",
-      "#Result\n",
       "print\"percent reduction in area is \",round(RA,0),\"%\"\n",
       "print\"True stress is \",round(sig_t,1),\"MPa\"\n",
       "\n"
@@ -218,16 +196,13 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Calculation of Strain-Hardening Exponent\n",
       "\n",
       "sig_t=415       #True stress in MPa\n",
       "et=0.1          #True strain\n",
       "K=1035.0         # In MPa\n",
       "\n",
-      "#Calculation\n",
       "n=(math.log(sig_t)-math.log(K))/math.log(et)\n",
       "\n",
-      "#Result\n",
       "print\"Strain - hardening coefficient is \",round(n,2)\n",
       "\n"
      ],
@@ -256,20 +231,16 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Average Computations\n",
       "\n",
-      "#Tensile strength at 4 points\n",
       "n=4.0        #No of points\n",
       "T1=520\n",
       "T2=512\n",
       "T3=515\n",
       "T4=522\n",
       "\n",
-      "#Calculation\n",
       "Tav=(T1+T2+T3+T4)/n\n",
       "s=(((T1-Tav)**2+(T2-Tav)**2+(T3-Tav)**2+(T4-Tav)**2)/(n-1))**(0.5)\n",
       "\n",
-      "#Result\n",
       "print\"The average Tensile strength is\",round(Tav,0),\"MPa\"\n",
       "print\"The standard deviation  is\",round(s,1),\"MPa\""
      ],
@@ -299,18 +270,14 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Specification of Support Post Diameter\n",
       "\n",
-      "#Given\n",
       "sig_y=310.0      #Minimum yield strength in MPa\n",
       "N=5.0            # Conservative factor of safety\n",
       "\n",
-      "#Calculation\n",
       "F=220000/2.0    #Two rods must support half of the total force\n",
       "sig_w=sig_y/N\n",
       "d=2*math.sqrt(F/(math.pi*sig_w))\n",
       "\n",
-      "#Result\n",
       "print\"Diameter of each of the two rods is \",round(d,1),\"mm\"\n",
       "\n"
      ],
diff --git a/Materials_science_and_engineering_an_introduction/CH7.ipynb b/Materials_science_and_engineering_an_introduction/CH7.ipynb
index ffef5715..262231ec 100644
--- a/Materials_science_and_engineering_an_introduction/CH7.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH7.ipynb
@@ -27,21 +27,17 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Resolved Shear Stress Computations\n",
       "\n",
-      "#Direction for given plane\n",
       "u1=1\n",
       "v1=1\n",
       "w1=0\n",
       "u2=0\n",
       "v2=1\n",
       "w2=0\n",
-      "#For lamda\n",
       "u3=-1\n",
       "v3=1\n",
       "w3=1\n",
       "\n",
-      "#Calculation\n",
       "import math\n",
       "phi=math.acos((u1*u2+v1*v2+w1*w2)/(math.sqrt((u1**2+v1**2+w1**2)*(u2**2+v2**2+w2**2))))\n",
       "lam=math.acos((u3*u2+v3*v2+w3*w2)/(math.sqrt((u3**2+v3**2+w3**2)*(u2**2+v2**2+w2**2))))\n",
@@ -50,7 +46,6 @@
       "trc=30         #in MPa Critical resolved shear stress\n",
       "sy=trc/(math.cos(phi)*math.cos(lam))\n",
       "\n",
-      "#Result\n",
       "print\"(a)The resolved shear stress is \",round(tr,2),\"MPa\"\n",
       "print\"(b)Yield strength is\",round(sy,1),\"MPa\"\n",
       "\n"
@@ -81,18 +76,14 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Tensile Strength and Ductility Determinations for Cold-Worked Copper\n",
       "\n",
-      "#Given\n",
       "df=12.2  #Final dia in mm\n",
       "di=15.2  #Initial dia in mm\n",
       "\n",
-      "#Calculation\n",
       "CW = ((di**2-df**2)/di**2)*100\n",
       "ts=340  #in Mpa  tensile strength, from fig 7.19 (b)\n",
       "duc=7   #in %  Ductility from fig 7.19 (c)\n",
       "\n",
-      "#result\n",
       "print\"Percent Cold Work is \",round(CW,1),\"%\"\n",
       "print\"Tensile strength is\",ts,\"MPa\"\n",
       "print\"Ductility is \",duc,\"%\"\n",
@@ -125,21 +116,13 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Description of Diameter Reduction Procedure\n",
       "\n",
-      "#Given\n",
       "di=6.4  #Initial dia in mm\n",
       "df=5.1  #Final dia in mm\n",
       "\n",
-      "#Calculation\n",
-      "#Cold Work Computation\n",
       "CW = ((di**2-df**2)/di**2)*100\n",
-      "#From Figures 7.19a and 7.19c, \n",
-      "#A yield strength of 410 MPa \n",
-      "#And a ductility of 8% EL are attained from this deformation\n",
       "dmid = math.sqrt(df**2/(1-0.215))\n",
       "\n",
-      "#Result\n",
       "print\"Cold work is \",round(CW,1),\"%\"\n",
       "print\"But required ductility and yield strength is not matched at this cold work\"\n",
       "print\"Hence required Cold work is 21.5 %\"\n",
diff --git a/Materials_science_and_engineering_an_introduction/CH8.ipynb b/Materials_science_and_engineering_an_introduction/CH8.ipynb
index 682a584f..b5a32873 100644
--- a/Materials_science_and_engineering_an_introduction/CH8.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH8.ipynb
@@ -27,18 +27,13 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Maximum Flaw Length Computation\n",
       "\n",
-      "#Given\n",
       "sigma=40*10**6    # in Pa  Tensile stress\n",
       "E=69*10**9        #Modulus of elaticity  in pa\n",
       "Ys=0.3            #Specific surface energy  in N/m**2\n",
       "\n",
-      "#Calculation\n",
-      "#Maximum length of a surface flaw\n",
       "a=2*E*Ys/(math.pi*sigma**2)\n",
       "\n",
-      "#Result\n",
       "print\"Maximum lemgth of a surface flaw without fracture is \",round(a*10**6,1),\"micro m\"\n",
       "\n"
      ],
@@ -67,19 +62,13 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#Rupture Lifetime Prediction\n",
       "\n",
-      "#Given\n",
       "T=800.0+273.0      # Temperature in K\n",
       "\n",
-      "#Calculation\n",
       "import math\n",
-      "#From Graph of Fig. 8.32 Larson-Miller Parameter is deduced\n",
       "L_M=24*10**3\n",
-      "#math.log(t)=((L_M/T)-20)\n",
       "t=math.pow(10,(L_M/T)-20)\n",
       "    \n",
-      "#result\n",
       "print\"Time to rupture is \",round(t,0),\"h\"\n",
       "\n"
      ],
diff --git a/Materials_science_and_engineering_an_introduction/CH9.ipynb b/Materials_science_and_engineering_an_introduction/CH9.ipynb
index 0953b608..0ddab2a7 100644
--- a/Materials_science_and_engineering_an_introduction/CH9.ipynb
+++ b/Materials_science_and_engineering_an_introduction/CH9.ipynb
@@ -27,15 +27,11 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#(a)Determination of Phases Present\n",
-      "#(b)Computation of Phase Compositions\n",
       "\n",
-      "#Given\n",
       "C1=40.0    # Overall alloy composition\n",
       "Cb=98.0\n",
       "Ca=10.0\n",
       "\n",
-      "#Calculation\n",
       "Wa=(Cb-C1)/(Cb-Ca)\n",
       "Wb=(C1-Ca)/(Cb-Ca)\n",
       "d_Sn=7.24        # in g/cm**3  density of tin\n",
@@ -50,7 +46,6 @@
       "Vb=Wb/(d_b*((Wa/d_a)+(Wb/d_b)))\n",
       "\n",
       "\n",
-      "#Result\n",
       "print\"Mass fractions for alpha and beta phases are  respectively\",round(Wa,2),\"and\",round(Wb,2)\n",
       "print\"Density of alpha phase is  \",round(d_a,2),\"g/cm**3\"\n",
       "print\"Density of beta phase is   \",round(d_b,2),\"g/cm**3\"\n",
@@ -87,16 +82,11 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "#(a)Determining ferrite and cementite phase\n",
-      "#(b)Determining proeutectoid ferrite and pearlite\n",
-      "#(c)Determining eutectoid ferrite\n",
       "\n",
-      "#Given\n",
       "C0=0.35\n",
       "Ca=0.022\n",
       "C_Fe3C=6.7\n",
       "\n",
-      "#Calculation\n",
       "Wa=(C_Fe3C-C0)/(C_Fe3C-Ca)\n",
       "W_Fe3C=(C0-Ca)/(C_Fe3C-Ca)\n",
       "C_p=0.76\n",
@@ -107,7 +97,6 @@
       "Wa=(C_Fe3C-C0)/(C_Fe3C-Ca)\n",
       "Wae=Wa-W_a\n",
       "\n",
-      "#result\n",
       "print\"Mass fraction of total ferritic phase is\",round(Wa,2)\n",
       "print\"Mass fraction of Fe3C is\",round(W_Fe3C,2)\n",
       "print\"Mass fraction of Pearlite is\",round(Wp,2)\n",
-- 
cgit