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"Ligan 4?-(2-thienyl)-2,2?-6?,2?-terpyridine telah berhasil disintesis menggunakan metode Kröhnke. Hasil yang diperoleh berupa padatan kuning sebesar 34 % dan dikarakterisasi menggunakan spektrofotometer UV-Visible, spektrofotometer IR dan Spektrometer NMR. Ligan kemudian dikompleksasi dengan ion Zn2+ membentuk kompleks [Zn(4?-(2-thienyl)-2,2?:6?,2?-terpyridine)(NO3)2]. Aplikasi senyawa kompleks ini sebagai fluorosensor tipe on-off untuk logam berat dilakukan dengan menggunakan spektrofluorometer. Hasil studi menunjukkan bahwa senyawa kompleks [Zn(4?-(2 thienyl)-2,2?:6?,2?-terpyridine)(NO3)2] dapat dijadikan fluorosensor untuk ion Cu2+ karena penambahan ion ini menyebabkan penurunan intensitas fluoresensi dan pergeseran puncak serapan maksimum senyawa kompleks secara signifikan dibanding ion-ion logam lain seperti Mn2+, Fe2+, Co2+, Ni2+, Cd2+ dan Hg2+. Hal ini diperkirakan dapat terjadi karena kestabilan logam Cu dan ligan 4?- (2-thienyl)-2,2?-6?,2?-terpyridine yang lebih tinggi daripada senyawa kompleks [Zn(4?-(2-thienyl)-2,2?:6?,2?-terpyridine)(NO3)2] sehingga penambahan ion Cu2+ dapat mensubtitusi atom pusat senyawa kompleks tersebut dan menghasilkan senyawa baru yang bersifat non-fluoresens. Senyawa kompleks [Zn(4?-(2-thienyl)- 2,2?:6?,2?-terpyridine)(NO3)2] dapat mendeteksi ion Cu2+ secara selektif hingga konsentrasi 10-6 M.

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Ligand 4?-(2-thienyl)-2,2?:6?,2?-terpyridine has been synthesized using Kröhnke method. The solid yellow precipitate was 34 % and characterized by UV-Visible spectrophotometer, Infrared spectrophotometer and NMR spectrometer. This ligand has been coordinated to Zn2+ ion to form [Zn(4?-(2-thienyl)-2,2?:6?,2?- terpyridine)(NO3)2] complex. The application of this complex as on-off fluorosensor for heavy metal was studied by using spectrofluorometer. This study revealed that [Zn(4?-(2-thienyl)-2,2?:6?,2?-terpyridine)(NO3)2] complex can be used as fluorosensor for Cu2+ ion since this ion quenched the fluorescence intensity and shifted the fluorescence maxima of the complex significantly compared to other metal ions such as Mn2+, Fe2+, Co2+, Ni2+, Cd2+ dan Hg2+. The fluorescence shift is happened due to the complex stability of Cu complex is higher than Zn complex. Therefore, the addition of this metal can substitute the central atom of the complex and form the new non-fluorescent compound. [Zn(4?-(2-thienyl)-2,2?:6?,2?- terpyridine)(NO3)2] complex can detect Cu2+ ion selectively up to concentration 10-6 M."

"Ligan 4'-(2-thienyl)-2,2'-6', 2‖-terpyridine telah berhasil disintesis menggunakan metode Kröhnke. Hasil yang diperoleh berupa padatan kuning sebesar 44% dan dikarakterisasi menggunakan spektrofotometer UV-Visible, spektrofotometer IR dan Spektrometer NMR. Ligan kemudian dikompleksasi dengan dengan ion Eu3+ dan Dy3+ membentuk kompleks [Eu(4'-(2-thienyl)-2, 2':6', 2‖-terpyridine)(NO3)3] dan [Dy(4'-(2-thienyl)-2, 2':6',2‖-terpyridine)(NO3)3]. Aplikasi senyawa kompleks ini sebagai fluorosensor untuk logam berat dilakukan dengan menggunakan spektrofluorometer. Hasil studi menunjukkan bahwa senyawa kompleks ini dapat dijadikan fluorosensor tipe on-off untuk ion Pb2+ karena penambahan ion ini menyebabkan penurunan intensitas fluoresensi dan pergeseran puncak serapan maksimum senyawa kompleks secara signifikan dan fluoresensor tipe off-on untuk ion Cd2+ karena penambahan ion ini menyebabkan peningkatan intensitas fluoresensi secara signifikan. Hal ini diperkirakan dapat terjadi karena kestabilan logam kedua logam berat ini dan ligan 4'-(2-thienyl)-2,2'-6', 2‖-terpyridine yang lebih tinggi daripada senyawa kompleks [Eu(4'-(2-thienyl)-2, 2':6', 2‖-terpyridine)(NO3)3] dan [Dy(4'-(2-thienyl)-2, 2':6', 2‖-terpyridine)(NO3)3] sehingga dapat mensubtitusi atom pusat senyawa kompleks tersebut dan menghasilkan senyawa baru. Senyawa kompleks [Dy(4'-(2-thienyl)-2, 2':6',2‖-terpyridine)(NO3)3] merupakan yang lebih baik dalam mendeteksi keberadaan ion Pb2+ dan Cd2+ daripada senyawa kompleks [Eu(4'-(2-thienyl)-2,2':6', 2‖-terpyridine)(NO3)3]. Hal ini disebabkan karena kompleks tersebut mampu mendeteksi kedua ion logam berat hingga 5 x 10-6 M, sementara kompleks [Eu(4'-(2-thienyl)-2,2':6', 2‖-terpyridine)(NO3)3] hanya bertahan di konsenttrasi 5 x 10-5 M.

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Ligand 4'-(2-thienyl)-2,2':6',2‖-terpyridine has been synthesized using Kröhnke method. The solid yellow precipitate was 22 % and characterized by UV-Visible spectrophotometer, Infrared spectrophotometer and NMR spectrometer. This ligand has been coordinated to Eu3+ and Dy3+ to form [Eu(4'-(2-thienyl) 2,2':6',2‖-terpyridine)(NO3)3] and [Dy(4'-(2-thienyl)-2, 2':6', 2‖-terpyridine)(NO3)3] complex. The application of this complex as fluorosensor for heavy metal was studied by using spectrofluorometer. This study revealed that both of the complex can be used as fluorosensor on-off type for Pb2+ ion since this ion quenched the fluorescence intensity and shifted the fluorescence maxima of the complex significantly and fluorosensor off-on type for Cd2+ ion since this ion enhanced the fluorescence intensity and shifted the fluorescence maxima of the complex significantly. The fluorescence shift is happened due to the complex stability of both of heavy metal ions is higher than [Eu(4'-(2-thienyl)-2, 2':6', 2‖-terpyridine)(NO3)3] and [Dy(4'-(2-thienyl)-2,2':6', 2‖-terpyridine)(NO3)3] complex. Therefore, the addition of this metal can substitute the central atom of the complex and form the new compound. [Dy(4'-(2-thienyl)-2,2':6', 2‖-terpyridine)(NO3)3] complex is the best fluorosensor for both of heavy metal ions compared [Eu(4'-(2-thienyl)-2,2':6', 2‖-terpyridine)(NO3)3] complex because the complex can detect both of heavy metal ions up to concentration 10-6 M. [Eu(4'-(2-thienyl)-2,2':6', 2‖-terpyridine)(NO3)3] complex can detect up to concentration 10-5 M onl"

"This book about more than just distances from electron density studies, modeling and analysis of hydrogen atoms, charge density methods in hydrogen bond studies. some main group chemical perceptions in the light of experimental charge density investigations. electronic structure and chemical properties of lithium organics seen through the glasses of charge density. bond orders in metal–metal interactions through electron density analysis, and on the nature of β-agostic interactions : a comparison between the molecular orbital and charge density picture."

"Pada penelitian ini, nanopartikel Cr-doped ZnO dengan kosentrasi Cr yang berbeda (3-16%) telah disintesis dengan metode kopresipitasi. Struktur, sifat optik dan sifat magnetik sampel yang dihasilkan telah dikarakterisasi dengan XRD (Xray Diffraction), EDX (Energy Dispersive X-ray, FTIR (Fourier Transform Infra Red), spektroskopi UV-Vis, ESR (Electron Spin Resonance) dan VSM (Vibrating Sampel Magnetometer). Hasil karakterisasi XRD (X-ray Diffraction) dan EDX (Energy Dispersive X-Ray) menunjukkan bahwa Cr telah bergabung ke dalam ZnO (fase hexagonal wurtzite) tanpa adanya fase kedua. Hasil tersebut menunjukkan bahwa doping Cr menghambat pertumbuhan kristal. Pergeseran merah pada absorbsi band edge pada spektrum absorbansi UV-Vis dengan peningkatan konsentrasi Cr juga mengkonfirmasi doping Cr pada ZnO. FTIR telah dipelajari untuk mengindentifikasi karakteristik frekuensi vibrasi ikatanikatan kimia pada sampel. Hasil ESR menunjukkan penambahan ion Cr 3+ yang mungkin berkontribusi dalam pembentukkan sifat magnet yang diperoleh pada hasil karakterisasi VSM.

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In this research, Cr-doped ZnO nanoparticles with different concentrations of Cr (3-16%) were synthesized by coprecipitation method. The Structure, the optical and the magnetic properties of the produced samples were characterized by XRD (X-ray Diffraction), EDX (Energy Dispersive X-ray, FTIR (Fourier Transform Infra Red), UV-Vis spectroscopy, ESR (Electron Spin Resonance) and VSM (Vibrating Sampel Magnetometer). The XRD (X-ray Diffraction) dan EDX (Energy Dispersive X-Rays) characterization results indicated that Cr has been incorporated into ZnO (hexagonal wurtzite phase) without any secondary phase.

The results indicated that Cr-doping restrained the growth of the crystal. The red shift in band edge absorbtion in UV-Vis absorbance spectrum with in increasing Cr concentration also confirm the doping of Cr in ZnO. FTIR have been studied in order to identify the characteristic frequencies of the vibrational chemical bonds. The ESR results indicated the addition of Cr3+ ions that may contribute in order the magnetic properties that was found in VSM characterization results."

"This book about new directions in pseudoatom-based X-ray charge density analysis, reliable measurements of dipole moments from single-crystal diffraction data and assessment of an in-crystal enhancement, challenging problems in charge density determination : polar bonds and influence of the environment, electron density in quantum theory, residual density analysis, the source function descriptor as a tool to extract chemical information from theoretical and experimental electron densities."

"Prof. Baev presents in his book the development of the thermodynamic theory of specific intermolecular interactions for a wide spectrum of organic compounds: ethers, ketones, alcohols, carboxylic acids, and hydrocarbons. The fundamentals of an unconventional approach to the theory of H-bonding and specific interactions are formulated based on a concept of pentacoordinate carbon atoms. New types of hydrogen bonds and specific interactions are substantiated and on the basis of the developed methodology their energies are determined. The system of interconnected quantitative characteristics of the stability of specific intermolecular interactions is presented. The laws of their transformations are discussed and summarized. The new concept of the extra stabilizing effect of isomeric methyl groups on the structure and stability of organic molecules is introduced and the destabilization action on specific interactions is outlined."

"ABSTRAKTelah dilakukan sintesis polimer konduktif melalui proses rekayasa polimerisasi anilin menjadi Polyaniline Emeraldine Salt (PANi-ES). Penetralan sifat PANi diperoleh setelah proses pencucian sehingga berubah menjadi Polyaniline Emeraldine Base (PANi-EB). Tahapan ini dilanjutkan dengan tahapan pengkayaan muatan listrik melalui proses protonasi beberapa jenis garam (KSO4, KCl, K2CO3 dan NaSO4) dalam kurun waktu 10 jam untuk menjadi PANi conductive. Proses polimerisasi dimulai setelah pencampuran antara larutan HCl mengandung anilin dan larutan HCl mengandung Ammonium Persulphate (APS). Berlangsungnya proses polimerisasi disertai dengan peningkatan temperatur, kekentalan, ukuran partikel serta perubahan warna larutan. Hasil karakterisasi terhadap larutan selama berlangsungnya proses polimerisasi menunjukkan bahwa kekentalan larutan meningkat dari 426 mPa.s menjadi 1315 mPa.s; ukuran partikel rata-rata naik dari 6 m menjadi 33 m. Peningkatan nilai kekentalan dan ukuran rata-rata partikel terkait dengan pembentukan dan pertumbuhan rantai polimer pada tahapan inisiasi dan propogasi. Proses polimerisasi berhenti ketika tidak lagi terjadi perubahan indicator laruran. Pengkayaan muatan melalui pemberian larutan garam telah meningkatkan nilai konduktivitas listrik PANi. Namun nilai konduktivitas PANi terbesar hanya diperoleh dari protonasi garam KCl sebesar 2,12 x 10-4 S/cm. Hasil karakterisasi PANi dengan FTIR memastikan bahwa pola serapan IR yang diperoleh adalah pola serapan PANi dan protonasi dengan garam tidak mempengaruhi pola serapan IR. Lalu, hasil karakterisasi dengan menggunakan Xray difraksi menunjukan persebaran atom yang tidak teratur atau amorf pada sekitar 2Ɵ = 25°. Disimpulkan bahwa, sintesis PANi conductive melalui proses polimerisasi dan pengkayaan muatan dengan larutan garam telah tercapai dengan baik.

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ABSTRAKConductive polymer has successfully been synthesized through the engineering process of polymerization of aniline containing solution toward the Polyaniline Emeraldine Salt (PANi-ES) as the intermediate product. Deprotonation of PANiES was carried out through a cleaning treatment of PANi-ES by washing. To this stage the PANi-ES changed to the Polyaniline Emeraldine Base (PANi-EB). The stage of enrichment of PANi by electric charges was conducted through protonation process using some types of salt (K2SO4, KCl, K2CO3 and NaSO4) within 10 hours duration time of polimerization. The polymerization process begins after the mixing between the HCl solution containing aniline and HCl solution containing Ammonium Persulphate (APS). The course of the polymerization process was accompanied by an increase in temperature, viscosity, particle size and the color changes of the solution. Results of the characterization of the solution during the polymerization process showed that the viscosity of the solution increased from 426 mPa.s to 1315 mPa.s; The mean particle size increased from 6 m to 33 m. The increased in viscosity values and mean particle sizes associated with the formation and growth of the polymer chains during initiation and propogation process. The polymerization process stopped when there have bee no longer indicators change in the solution. Enrichment of electrical charges through the protonation by salt solution has improved the electrical conductivity values of the PANi. But the largest conductivity value of 2.12 x 10-4 S/cm for the PANi was obtained only from protonated by KCl. The characterization of enriched PANi as the final product with FTIR ensure that the IR absorption pattern is the typical that of PANi. Protonated with salt to the PANi does not affect the pattern of IR absorption. Then, The X-ray diffracton pattern indicates that the chains are strong disordered. The doped PANi shows a broad amorphous scattering aroung 2Ɵ = 25°. It is concluded that, the synthesis of conductive PANi through polymerization and electrical charge enrichment with salt solution has been successfully reached."