NPL Final cover ).crystals with larger diameters up to 40 mm have been grown to meet the device...

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Transcript of NPL Final cover ).crystals with larger diameters up to 40 mm have been grown to meet the device...

  • inkFkZ vfHky{k.ku

    inkFkksZ ds vfHky{k.ku ds vUrxZr la?kVu vkSj lajpuk dh mu fo”ks’krkvksa dk o.kZu fd;k tkrk gS tks fdlh fof”k’V rS;kjh] xq.k/keksZa dk v/;;u vkSj@;k inkFkZ ds iqujksRiknu ds fy, i;kZIr gksrs gSa A inkFkksZa ds xq.k/keksZa ds fy, mRrjnk;h muds vk/kkjHkwr esa mudk la?kVu vkSj “kq)rk] fØLVykbu volajpuk vkSj ijek.kq Lrj ij volajpuk dh laiw.kZrk “kkfey gksrh gS A ,u ih ,y esa inkFkZ ds fo”ys’k.k dh ;ksX;rk dk egRo] blds vk;kstu ds le; gh le> fy;k x;k Fkk A orZeku esa ,u ih ,y esa inkFkksZa ds vfHky{k ds fy, vR;k/kqfud vkSj uohure fHkUu & fHkUu lqfo/kk,sa miyC/k gSa A buesa ,Dl&js fo”ys”k.k ¼ ,Dl vkj Mh] ,Dl vkj ,Q] ,p vkj & ,Dl vkj Mh ½] bysDVªªkWu ekbØksLdksih ¼ ,l bZ ,e] Vh bZ ,e] bZ Mh ,Dl] ,p vkj&Vh bZ ,e ½] vk;u ekbØksLdksih ¼ Vh vks ,Q&,l vkbZ ,e ,l] vkbZ lh ih ,e ,l½] vkf.od LisDVªªksLdksih ¼ , , ,l ½] Ádk”kh; LisDVªªksLdksih ¼ ;w oh & oh vkbZ ,l] ih ,y ½] jklk;fud fo”ys’k.k ¼ th lh & bZ lh Mh] th lh & Vh lh Mh@,Q vkbZ Mh] ,p ih &,y lh ,e ,l ½] rFkk pqEcdh; ekiu ¼ bZ ih vkj ½ “kkfey gksrs gSa A

    inkFkZ vfHky{k.ku foHkkx }kjk ,u ih ,y esa fodflr fd, tk jgs vusd inkFkksZa tSls fFku fQYe] uSuks inkFkZ ftuesa uSuks V;wCl] uSuks jkM~l] uSuks ok;lZ] bathfu;jh vuqÁ;ksxksa ds fy, daiksftV inkFkZ] fMokbl Ýsfczds”ku ds fy, bysDVªªkWfud inkFkZ vkfn “kkfey gSa] ds vfHky{k.ku ls lacaf/kr dk;Z fd;k tk jgk gS A bl foHkkx }kjk Á;ksx”kkyk dh vuqla/kku ;kstuk dks /;ku esa j[krs gq,] ,sls bu fHkUu & fHkUu inkFkksZa ds fodkl dk dk;Z Hkh fd;k tk jgk gS tks fd ÁkS|ksfxdh; :i ls egRoiw.kZ gS ] rFkk muds fo”ys’k.k vkSj fodkl ds lkFk lkFk] fodkl ra= dh ÁfØ;k fu;a=.k ds b’Vrehdj.k ds fy, varr% vfHky{k.ku fd;k tkrk gS A vHkh gky gh esa] bl foHkkx }kjk X;kjgoha iapo’khZ; ;kstuk ds nkSjku ¼ bZ,Q Qh½ inkFkZ ekfidh vkSj jlk;u ekfidh dk;ZØe ds vUrxZr ykus ds fy, dne mBk, tk jgs gSa A

    1- inkFkZ ekfidh vkSj jlk;u “kkL= esa ekfidh dh ubZ xfrfof/k ds vUrxZr] ,u ih ,y }kjk vius fed (MiC) usVodZ lk>snkjksa ds lkFk jklk;fud ekiu esa vuqjs[k.kh;rk Ánku djus ds fy, /;ku dsfUær fd;k tk jgk gS ftldk y{; {kerk fuekZ.k] fofHkUu {ks=ksa esa vuqla/kku vkSj fodkl djus] vUrjkZ’Vªªªh; Á;ksfxd vkSj egRoiw.kZ rqyukRedrkvksa esa Hkkx ysus ds fy, djuk gS vkSj blesa çekf.kr lanHkZ inkFkksZa ¼lh

    vkj ,e½ dks rS;kj djuk vkSj laforj.k djuk Hkh “kkfey gS A ,u ih ,y ds vkarfjd vuqla/kku dk;Z] ljdkjh ,tsafl;ksa vkSj laLFkkuksa dh fofHkUu inkFkZ vfHky{k.k vko”;drkvksa tSls fnYyh ty cksMZ }kjk ikuh ds “kks/ku ds fy, ç;ksx fd, tk jgs ,Y;qfefu;e DyksjkbM vkSj ,Y;qfeuk QSfjd xzsM&2] Hkkjr ds

    fuokZpu vk;ksx dh vksj ls pquko mís”;ksa ds vfeV L;kgh ¼ baMsfycy bad ½ vfrfof”k’V O;fDr;ksa dh lqj{kk ds fy, xSl feJ.k vfHky{k.ku] xzsQkbV] DokV~Zt] flYoj dkUVsDV~l uewuksa vkfn esa /kkfRod v”kq}rkvksa ls lacaf/kr dqN egRoiw.kZ lsok,sa çnku dh xbZ gSa A

    2- mPp ckjEckjrk {ks=ksa esa ekbØksoso vo”kks’k.k ds fy, e`nq /kkfRod pqacd laHkkfor inkFkZ gS A bl lanHkZ esa uSuks eSxusfVd dksckYV vk;ju (Co Fe2 ) uSuks feJ/kkrq dks jklk;fud fçislhihVs”ku ekxZ ls la”ysf”kr fd;k x;k gs rFkk Ku cSaM (12-4 & 18 xsxk gV~tZ ) esa ekbØksoso vo”kks’k.k ds fy, fØLVsykbu vkdkj] v.kq vkdj] pqacdh;dj.k rFkk pkydrk ds laca/k esa fo”ys’k.k fd;k x;k A

  • 3- v/kZ Lopkfyr vkSj vk/kqfudhd`r bu&gkml fodflr ØkspkyLdh (Czochralski ) 40 feyhehVj ds cM++s O;kl rd ds fyfFk;e fuvkscsV (,y fØLVy iqyj ds lkFk vkj ,Q rkiu Á.kkyh dh lQyrkiwoZd LFkkiuk ds ckn] fuEurkih; xzsfM,UV ØkspkyLdh rduhd }kjk miLdj vuqç;ksxksa dks iwjk djus ds fy, vkbZ ,u ch vks

    3 ) fØLVyksa dks fodflr fd;k x;k gS A csgrj ;kaf=dh vkSj jklk;fud fLFkjrk vkSj foLr`r

    ikjnf”kZrk ds lkFk&lkFk fof”k’V bysDVªªks vkfIVdy ¼bZ&vks½] ,dkfLVd vkfIVd ¼,&vks½] QksVksbykfLVd] ihtks&bysfDVªd rFkk vjs[kh; vkWfIVdy ¼ ,u ,y vks ½ xq.k/keksZa ds dkj.k fyfFk;e fuvkscsV vkWIVksbysfDVªªksfuDl ds fy, lcls vkd’kZd lkefxz;ksa esa vkrk gS A 23 vkdZ ,l dh ,Q McY;w ,p ,e eku ds lkFk rhoz vkSj ,dy mPpre fMÝsD”ku oØrk }kjk , ,l&xzksu fØLVy dh “kkunkj xq.koÙkk dks n”kkZrk gS ftlls njkjsa vkSj vkarfjd voljpukRed xzsu lhek,aa fn[kkbZ ugha nsrh gSA

    4- xzkQsu vkDlkbM usuks”khV~l ¼,d ?kksy vk/kkfjr ,dy pj.k fof/k tks xzkQsu vkDlkbM uSuks”khV~l esa flYoj uSuksikfVZdYl dks varfuZfgr djrh gS ½ esa flYoj uSuksikfVZdYl dks vUrfuZfgr djds xzkQsu /kkrq uSuksgkbZfczM vlsEcfy;ksa dks la”ysf’kr fd;k x;k gS A bl izdkj xzkQsu “khV~l ds vkIVks bysfDVªd xq.k/keksZa dks eSXuhV;wM ds vusd vkMZjksa esa V;wu fd;k tk ldrk gS ftlls os laHkkfor ykspiw.kZ vkSj ikjn”khZ lsehdaMDVjksa vFkok v/kZ /kkrqvksa ds fy, laHkkfor rkSj ij mi;ksxh gks ldrs gSa A

    5- ,l vkbZ @Vh ,e ¼ Vªkaft”ku esVy ½ ,l vkbZ flLVe @ ,l vkbZ flLVe ¼oh @ ,l vkbZ] ,Q bZ @ ,l vkbZ rFkk lh vks @ ,l vkbZ ½ ds laca/k esa vius fiNys dk;ksZa dks tkjh j[krs gq,] ,d vU; Vªkaft”ku esVy vFkkZr~ ,e ,u dks vekjQl flfydkWu ¼ , ,l vkbZ ds lkFk fefJr djus dks pquk x;k gS D;ksafd bl /kkrq ij “kk;n gh dksbZ v/;;u fd;k x;k gks @ ,l vkbZ flLVe mPp & ÅtkZ jsthesu esa vkrk gS A ;gkW¡ rd fd ,l bZ & mPpre lhek eku ds laca/k esa dksbZ tkudkjh Hkh miyC/k ugha gS A feJ.k nj ds :i esa] bl dk;Z dks ,l ,p vkbZ & Ásfjr baVjQsl feJ.k dh ek=kRedrk dks fu/kkZfjr fd, tkus dk iz;kl gS ftlds ifj.kkeLo:ir% rkih; Likbd ekWMy ds ÝseodZ esa bl Áo`fÙk dks le>k tk lds vkSj nwljk bl ckr dh tk¡p djuk dh dejs ds rkieku ij dksbZ flfylkbMs”ku rks ugha gqvk gS A

  • MAMAMAMAMATERIALS CHARATERIALS CHARATERIALS CHARATERIALS CHARATERIALS CHARACTERIZACTERIZACTERIZACTERIZACTERIZATIONTIONTIONTIONTION

    Characterization of materials describes those features of the composition and structure (including defects) of a material, that are significant for a particular preparation, study of properties and/or suffice for the reproduction of the material. The basic characterization of materials responsible for their properties are the composition and purity, crystalline structure and perfection of structure at atomic level. The importance of the capability for material analysis at NPL was realized even at the time of its planning. Presently NPL has wide variety of state- of-the art sophisticated facilities for characterization of materials. These include X-ray analysis( XRD, XRF, HR-XRD), electron microscopy ( SEM, TEM, EDX, HR-TEM), ion microscopy (TOF-SIMS, ICPMS), atomic spectroscopy(AAS), optical spectroscopy (UV-VIS, PL), chemical analysis ( GC-ECD, GC-TCD/ FID, HP-LCMS) and magnetic measurements (EPR).

    Material characterization division has been characterizing various materials that are being developed at NPL, like thin films, nano materials including nano tubes, nano rods, nano wires, composite materials for engineering applications, electronic materials for device fabrication etc. The division is also working on development of different materials which are technologically important, their synthesis and growth and finally characterizing them for optimization in process control of the growth mechanism, keeping in view the research plan of the laboratory. In the recent past, the division has taken up a new programme under the eleventh five year plan (EFP), Material Metrology and Metrology in Chemistry. Under this programme the implementation of Quality system as per ISO 17025 is being pursued in the division and all the necessary steps are being taken to bring this division under ‘Advanced Metrology’ programme of NPL. 1. Under the new activity of Material Metrology and Metrology in Chemistry, focus has been given for

    providing traceability in chemical measurements by NPL with its MiC network partners by building capacity, doing R&D in various areas, participating in international pilot & key comparisons and includes preparation & dissemination of certified reference materials (CRMs). The chemical characterization needs of NPL in-house research work, government agencies and institutions for characterization of a variety of materials viz. poly aluminum chloride and Alumina Ferric Grade-II used for treatment of water by Delhi Jal Board; indelible ink for election purpose from Election Commission of India; gas mixtures characterization for VVIP security, metal impurities in graphite, quartz, silver contacts samples etc. are some of the important services rendered during this period.

    2. Soft metallic magnets are potential materials for microwave absorption in high frequency region. In this context nano-magnetic cobalt iron (CoFe2) nano-alloy have been synthesized by chemical coprecipitation route and studied for microwave absorption in the Ku band (12.4-18 GHz) region. Prepared material was analyzed for crystalline phase, crystallite size, particle size, magnetization and conductivity measurement relevance to microwave absorption.

  • 3. After successful installation of RF heating system with semi-automated and modernized in-house developed Czochralski crystal puller, good quality Lithium niobate (LiNbO3).crystals with larger diameters up to 40 mm have been grown to meet the device applications by a low thermal gradient Czochralski technique. Lithium niobate is one of the most attractive materials for optoelectronics due to its unique electro-optical (E-O), Acousto-Optic (A-O), photoelastic, piezo-electric and nonlinear optical (NLO) properties combined with good mechanical and chemical stability and wide transparency. The sharp and single peak diffraction curve having FWHM value of 23 arc s depicts the excellent quality of the as-grown crystal revealing the absence of cracks and internal structural grain boundaries.

    4. Graphene-metal nanohybrid assemblies have been synthesized by embeding the silver nanoparticles into graphene oxide nanosheets ( a solution-based single step meth