01783nas a2200169 4500008004100000022001400041245006900055210006800124260007100192300001400263490000800277520117600285100002601461700001401487700001901501856009301520 2014 eng d a1932-744700aLarge increase in the energy product of Fe3Se4 by Fe-site doping0 aLarge increase in the energy product of Fe3Se4 by Fesite doping a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcFEB a4016-40220 v1183 a

Fe3Se4 possesses a large coercivity at room temperature. At lower temperature, a coercivity value up to 40 kOe has been achieved. However, due to a relatively lower saturation magnetization value, the energy product of this material is not suitable for its use as rare-earth-free hard magnetic material. Although the anisotropy and magnetic structure of Fe3Se4 have been topics of research, there is no attempt to increase the energy product. Here, we report the synthesis of Fe3-xMnxSe4 (x = 0.01-0.2) nanorods. As required for practical applications, after doping, the Curie temperature remains unchanged; however, at optimum (x = 0.03) doping of manganese ions, the magnetization of the host matrix increases significantly from 4.84 to 7.54 emu/g. The corresponding energy product value was found to be increased by more than 130%. At low temperature (10 K) the energy product shows almost a 2 order of magnitude increase (similar to 0.12 MG Oe), which makes it valuable for many low temperature applications. This improvement is a vital step for its use in some of the household applications where a large volume and relatively lower energy product are needed.

1 aBishwas, Mousumi, Sen1 aDas, Raja1 aPoddar, Pankaj uhttps://library.ncl.res.in/content/large-increase-energy-product-fe3se4-fe-site-doping-001810nas a2200277 4500008004100000022001400041245010700055210006900162260007700231300001400308490000700322520084200329653001501171653001501186653002401201653001801225653002201243100002401265700001901289700001401308700002001322700003001342700001601372700002401388856012001412 2014 eng d a1439-423500aLarge magnetocaloric effect, moment, and coercivity enhancement after coating Ni nanoparticles with Ag0 aLarge magnetocaloric effect moment and coercivity enhancement af aBOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANYbWILEY-V C H VERLAG GMBHcJUN a1619-16230 v153 a

We observe a large magnetocaloric effect in monodisperse Ni and NicoreAgshell nanoparticles in the superparamagnetic region. The organically passivated Ni nanospheres show a large magnetic entropy change of 0.9 J kg(-1)K for a 3 T magnetic field change. In comparison to the surfactant-coated Ni nanoparticles, the NicoreAgshell nanoparticles show an enhanced coercivity, magnetization, and magnetocaloric effect (1.3 kgK for a 3 T magnetic field change). The coercivity at 10 K increases from 360 Oe for Ni nanoparticles to nearly 610 Oe for NicoreAgshell particles. This large enhancement is attributed to the enhanced inter-particle interaction, which is mediated by the metallic shell, over the relatively weaker dipolar interaction in the surfactant-coated Ni nanoparticles, and to modification of the surface spin structure.

10aanisotropy10acore-shell10amagnetic properties10aNanoparticles10asuperparamagnetic1 aSrinath, Sanyadanam1 aPoddar, Pankaj1 aDas, Raja1 aSidhaye, Deepti1 aPrasad, Bhagavatula L. V.1 aGass, James1 aSrikanth, Hariharan uhttps://library.ncl.res.in/content/large-magnetocaloric-effect-moment-and-coercivity-enhancement-after-coating-ni-001992nas a2200193 4500008004100000245012700041210006900168260000800237300001600245490000600261520127800267100001701545700001901562700002701581700002601608700001901634700001701653856012801670 2017 eng d00aLn(8) (Ln = Gd, Ho, Er, Yb) Butterfly core-exhibiting magnetocaloric effect and field-induced SMM behavior for Er analouge0 aLn8 Ln Gd Ho Er Yb Butterfly coreexhibiting magnetocaloric effec cDEC a11341-113450 v23 a

In this article, we report four pyridyl-pyrazolyl based poly-nuclear cluster complexes with Ln(8) {Ln = [Gd-8(III)(mu(3)-OH)(4)(L-1)(4)(DEA)(4)Cl-4](DMF)(2)(MeOH)(1), [Ho-8(III)(mu(3)-OH)(4)(L-1)(4)(DEA)(4)Cl-4](2), [Er-8(III)(mu(3)-OH)(4)(L-1)(4)(DEA)(4)Cl-4](DMF)(MeOH)(H2O)(3), [Yb-8(III)(mu(3)-OH)(4)(L-1)(4)(DEA)(4)Cl-4](DMF)(MeOH)(4) [DEA = Diethanolamine] cores. The impetus for this study was to explore the magnetic behaviour of lanthanide ions which are often ignored or overlooked. X-ray crystal analysis show that these complexes are isostructural and exhibit an interesting butterfly like topology. The semi-rigidity and asymmetric nature of the ligand led to different coordination environment around the metal centres. The lanthanide ions adopt two types of geometry, a bicapped trigonal prism and a distorted square antiprismatic geometry around the metal center. Such dissimilar coordination environments around the lanthanide centre can have profound effects on their magnetic behaviour. Indeed, the magnetic measurements revealed significant magnetocaloric effect for octanuclear gadolinium complex 1 with magnetic entropy change (-Delta S-m ) of 31.4 J kg(-1) K-1 for Delta H = 9 T at T = 3 K whereas Er analogue complex 3 displayed SMM behavior.

1 aBala, Sukhen1 aAdhikary, Amit1 aBhattacharya, Sudeshna1 aBishwas, Mousumi, Sen1 aPoddar, Pankaj1 aMondal, Raju uhttps://library.ncl.res.in/content/ln8-ln-gd-ho-er-yb-butterfly-core-exhibiting-magnetocaloric-effect-and-field-induced-smm01363nas a2200205 4500008004100000022001400041245009300055210006900148260000800217300001200225490000700237520068100244100002100925700001700946700001800963700001800981700001800999700001901017856012101036 2022 eng d a2159-685900aLuminescence turn-off detection of metal ions and explosives using graphene quantum dots0 aLuminescence turnoff detection of metal ions and explosives usin cAPR a168-1740 v123 a

Green luminescent graphene quantum dots (GQDs) obtained from combustion of white printing paper were used for detection of fourteen different metal ions and six different explosives in an aqueous medium. These were obtained using a microwave-assisted synthesis process. After optimizing the experimental conditions (pH 6; quantum yield (QY) similar to 38.2%), a sensitive sensing system was developed to detect explosives and free residual metal ions in the environment based on fluorescence quenching of GQDs. The as-synthesized GQDs, as a sensing system, is most sensitive for Cu2+ ion and 2,4-DNP with a detection limit of 0.62 mu M and 0.50 mu M, respectively.

1 aJyotsna, Shubhra1 aSadhu, Subha1 aSharma, Vinay1 aGupta, Preeti1 aSharma, Geeta1 aPoddar, Pankaj uhttps://library.ncl.res.in/content/luminescence-turn-detection-metal-ions-and-explosives-using-graphene-quantum-dots