Oxidation of Metals

This thesis is concerned with the study the behaviour of UF6, MoF6, WF6 and NO+ towards the metals Co, Ni and Zn in CH3CN medium, and thus give a better insight into the reactivity of these hexafluorides towards first row transition elements. Solvated Co(II) has been prepared by the oxidation reactions of the metal by MoF6, WF6 and NO+. The solvated salt [Co(NCMe)6]-[PF6]2 is stable in absence of moisture and oxygen and can be stored in an argon atmosphere glove box. [Co(NCMe)6][WF6]2 and [Co(NCMe)6]-[MoF6]2 are very prone to hydrolysis and can be kept in liquid nitrogen for only one or two days. The spectra of the salts are consistent with octahedrally coordinated Co(II). Values of the ligand field splitting parameters (A) and electronic repulsion parameter (B') have been calculated and compared with those of some relevant CoL62+. They were found to fit the theoretical expectations and showed that acetonitrile is a good coordinating agent though not the strongest in the spectrochemical series. Co(II) can be electrochemically oxidised to Co(III) in cases where the counter anion is PF6-. This is not observed when WF6 - is the counter anion, which is probably due to the oxidation potentials of the Co2+/Co3+ and WF7- /W V couples which occur in the same range, hence the wave assigned to Co2+/Co3+ could not be observed. MoF6, oxidises cobalt metal to Co(II). Further oxidation, as would be predicted from the electrochemistry of [Co(NCMe) [PF6]2 was not observed, probably kinetic reasons. UF6 did not react with cobalt metal. Polymerisation of acetonitrile and reduction of UF6 took place instead. Zinc is not a transition metal but its behaviour towards the hexafluorides of uranium, molybdenum and tungsten, is similar to that of most of the first row transition elements. The metal is oxidized by MoF6, NO+ and WF6 and the salt [Zn(NCMe)6] [MF6]2 (M=Mo,P,W) is generated in solution. Coordination of acetonitrile and presence of the anion, MF6- (M=Mo,P,W), has been established from the study of its infrared and Raman spectra. UF6 does not oxidize zinc metal. Nickel metal is not oxidized by MoF6 and UF6 but it is relatively easily oxidized by NO+ and WF6 at room temperature. The solid [Ni(NCMe)6] [PF6]2 is stable at room temperature but [Ni(NCMe)6] [WF6]2 hydrolyses easily. A purple [Ni(NCMe)6] [WF6] 2 is formed when the oxidation of the metal is performed in acetonitrile solution. A fluoride ion transfer occurs in parallel, in which the hexafluorotungstate(V) anion behaves as a fluoride ion donor in acetonitrile. It reacts with WF6 to give WF7-, anion as a product. When the reaction is performed in the gas phase [Ni(NCMe)5]-[WF6]2, a white solid is formed. Neither MoF6, nor UF6, is able to oxidize massive nickel, MoF6, can,however oxidize chemically cleaned nickel metal or vacuum evaporated nickel film. A purple salt is formed; it is identified as [Ni(NCMe)6] [MoF6]2. If the nickel film is exposed to air before reaction, MoF6, does not oxidize it. This clearly shows that it is the oxide film that inhibits the reaction. On the other hand WF6, which reacts easily with massive nickel, is inert towards a nickel film free from its oxide layer. The reaction of an evaporated nickel film with WF5-18F shows that tungsten hexafluoride is adsorbed on the surface of the metal but this reaction could not be observed for kinetic reasons. Although previous workers did not take into account the role of the oxide film during the oxidation of metals, the series of reactions described above shows clearly its importance in the oxidation process. On this basis it seemed reasonable to assume that an electron transfer takes place between the oxide film and the oxidizing agent. Nickel oxide being stable, the electron transfer does not occur with MoF6. WF6 being a strong Lewis acid, it is able to form a Lewis Acid-Lewis-Base adduct which catalyses the oxidation reaction of nickel metal. Addition of pyridine to a solution mixture of nickel and MoF6 in MeCN produced a yellow solid. Its microanalysis revealed that it is in fact MoF5.2py adduct which is formed. The reaction was also performed in absence of nickel, yielding the same product, identified by microanalysis, atomic absorption and vibrational spectroscopy. Uranium hexafluoride is reported to be the strongest oxidizing agent of the series considered in this study. There was, however, no evidence of any reaction occurring between the metals, cobalt, nickel and zinc and UF6. In all cases, reduction of the hexafluoride occurred before reaction with the metal could be detected. This was followed by polymerisation of the solvent. UF6 was also reacted with a vacuum evaporated nickel film. In this case also, no reaction was observed

Analysis of chlorinated, sulfochlorinated and sulfonamide derivatives of n-tetradecane by gas chromatography/mass spectrometry

The photosulfochlorination of n-tetradecane by sulfuryl chloride leads to a reaction mixture containing unreacted n-tetradecane, chloro n-tetradecanes and n-tetradecanesulfonyl chlorides. Direct and simultaneousGCanalysis of the mixture of the sulfochlorinated and chlorinated isomers is followed by mass spectrometry identification of all the components either by electron impact (EI-MS) and by negative and positive chemical ionisation (NCI-MS and PCI-MS). With the goal of performing an accurate quantitative GC analysis, and as n-tetradecanesulfonyl chlorides prone to degrade partially into the corresponding chlorides, the former are converted to N,N-diethylsufonamides, more stable thermally, and then analysed by GC/EI-MS and GC/PCI-MS. The chloro n-tetradecanes, sulfonylchlorides and sulfonamides spectra present strong similarities. However, some differences between terminal and internal isomers are noticed and the peculiar behaviour of sulfonamides is emphasized

Molecular subtypes of intestinal-type gastric cancer: Association with T-lymphocytes and formins

Despite the decline of gastric cancer (GC) incidence in Western countries over the last decade, it is still one of the most significant causes of cancer mortality worldwide. The traditional morphology-based grading systems, including the world health organization (WHO) and Lauren's grading systems, have limited applicability in managing treatment choices, as they poorly catch the molecular heterogeneity of GC. Thus, classifications based on molecular features are needed. Recent genome analyses have shown that GC consists of several molecular subtypes characterized by distinct alterations. In our study, we used tissue-based methods, i.e., immunohistochemistry and in situ hybridization, in the molecular classification of GC, emphasizing the intestinal subtype. Our results show that GC can be divided into four nonoverlapping subtypes based on Epstein-Barr virus (EBV) positivity, mismatch repair protein (MMR), and TP53 aberration status. In conclusion, GC molecular subtyping can be performed with a simple methodology applicable to clinical routine. Host immune response is an important predictive and prognostic factor in many cancer types, including GC. Detailed information on the accumulation of tumorinfiltrating T lymphocytes in the different molecular GC subtypes and their prognostic correlation is scarce. We analyzed the presence of CD3+, CD8+, and FOXP3+ (Forkhead box P3) T lymphocytes in the molecular subtypes of intestinal-type GC. We found that EBV+ cancers harbor increased lymphocyte infiltration and a high CD8+/FOXP3+ ratio. In addition, we found that high numbers of CD8+ and CD3+ T lymphocytes are associated with better survival, and their accumulation is an independent prognostic factor. Formin proteins regulate the actin cytoskeleton and cell migration and play an essential role in cancer call functions. However, the expression and clinical association of formins in GC remains largely undiscovered. Here we analyzed the expression of FHOD1 and FMNL1 formins in GC cell lines and clinical samples of intestinal- type GC. We found that FHOD1 expression in cancer cells correlated with high intratumoral CD8+ T lymphocyte infiltration. Reduced FHOD1 expression was seen in the tumors with aberrant TP53. FMNL1 expression in cancer cells was associated with the size of the tumors and the stage of the disease. The results demonstrate a link between FHOD1 and FMNL1 expression with biological features of GC. However, we did not find a correlation between formin expression and GC prognosis.Suolistotyyppisen mahasyövän molekyylityypit: Assosiaatio T-lymfosyyttien ja forminien kanssa Vaikka mahasyövän esiintyminen on viime vuosikymmeninä laskenut kehittyneissä maissa, se on edelleen yksi tärkeimmistä syöpäkuolemien aiheuttajista. Mahasyöpä on biologialtaan monimuotoinen. Tästä syystä perinteinen kudosmorfologiaan perustua luokittelu, kuten WHO:n tai Laurénin luokitus, hyödyttää hoitopäätöksien tekoa vain rajallisesti. Molekulaarisiin piirteisiin perustuvan luokituksen kehittäminen olisikin tärkeää. Genomianalyyseihin perustuva tutkimus on osoittanut, että mahasyöpä koostuu useista molekulaarisista alatyypeistä. Analyysimenetelmät ovat kuitenkin monimutkaisia ja vaativat erityisosaamista. Tutkimuksessamme käytimme kliiniseen käyttöön soveltuvia menetelmiä; immunohistokemiaa ja in situ-hybridisaatiota mahasyöpien luokitteluun. Tulosten perusteella yksinkertaisen algoritmin avulla mahasyövät voidaan luokitella eri alaryhmiin Ebstain-Barr virus-positiivisuuden, TP53 poikkeavuuden ja MMR-puutoksen perusteella. Kliinisesti eroaviin alaryhmiin tapahtuva jaottelu voidaan siis toteuttaa yksinkertaisella ja kliiniseen diagnostiikkaan soveltuvalla menetelmällä Immuunijärjestelmän toiminta on tärkeä syövän ennusteen kannalta. Yksityiskohtaista tietoa siitä, miten T solut hakeutuvat eri mahasyövän alatyyppeihin ja liittyvät taudin käyttäytymiseen ei toistaiseksi ole. Tässä tutkimuksessa analysoimme CD3, CD8 ja FOXP3 antigeenejä ilmentävien T-lymfosyyttien esiintymistä intestinaalisen mahasyövän alatyypeissä. Tulosten perusteella EBV+ syövissä on runsaimmin T-lymfosyyttejä ja korkein CD8+/FOXP3-suhde. Totesimme myös, että runsas T-lymfosyyttien määrä korreloi intestinaalisen mahasyövän parempaan ennusteeseen ja toimii itsenäisenä ennustetekijänä. Formiiniproteiinit säätelevät solujen aktiinitukirankaa ja solujen migraatiota, ja ovat tärkeitä syöpäsolujen toiminnassa. Kuitenkin formiinien esiintymistä ja tehtäviä mahasyövässä tunnetaan huonosti. Tässä tutkimuksessa analysoimme FHOD1 ja FMNL1 formiineja mahasyöpäsolulinjoissa ja intestinaalista alatyyppiä edustavien mahasyöpien kudosnäytteissä. Kasvainsolujen FHOD1:n ilmentyminen oli yhteydessä korkeaan intratumoraalisten T-lymfosyyttien määrään. FHOD1:n alentunutta ekspressiota nähtiin syövän alatyypissä, johon liittyy TP53 mutaatio. FMNL1:n ilmentyminen puolestaan korreloi kasvaimen kokoon ja taudin leviämisasteeseen. Tulosten perusteella FHOD1 ja FMNL1-formiinien ilmentyminen liittyy mahasyövän biologisiin piirteisiin, joskaan ilmentymisellä ei näytä olevan yhteyttä mahasyövän ennusteeseen

The Effectiveness Of Islamic Cognitive Behavioral Therapy With Selected Islamic Content For Depressed Adults In Libya

Tujuan utama penyelidikan ini adalah untuk mendesain model kognitif tingkah laku Islam yang terdiri daripada teori Islam tentang kemurungan dan terapi kognitif Islam (CBT-IP) dan menyelidik keberkesanan CBT-IP dalam merawat golongan dewasa yang mengalami kemurungan. The main purpose of this study was to design an Islamic cognitive behavioral model that comprises an Islamic theory of depression and Islamic cognitive behavioral therapy (CBT-IP) and examine the effectiveness of CBT-IP in treating depressed adults

Low cycle fatigue life improvement of AISI 304 by initial and intermittent wire brush hammering

The effects of hammering by wire brush as a method of improving low cycle fatigue life of highly ductile austenitic stainless steel AISI 304 have been investigated through an experimental study combining imposed strain fatigue tests and assessment of surface characteristic changes under cyclic loading by SEM examinations and XRD analysis. It has been shown that the fatigue life of wire brush hammered surface was increased by 307% at an imposed strain rate of 0.2% and only 17% at an imposed strain rate of 0.5%, comparatively to the turned surface. This increase in fatigue life is explained in terms of fatigue damage that is related to crack networks characteristics and stability which are generated during fatigue on both turned and wire brush hammered surfaces. The improvement of brushed surface is attributed to the role of the surface topography, the near surface stabilized compressive residual stresses and superfi-cial cold work hardening on the fatigue crack network nucleation and growth. It is found that wire brush hammering produces a surface texture that favors, under cyclic loading, nucleation of randomly dispersed short cracks of the order of 40 lm in length stabilized by the compressive residual stress field that reached a value of r0 = 749 MPa. In contrast, turned surface showed much longer unstable cracks of the order of 200 lm in length nucleated in the machining groves with high tendency to propagate under the effect of tensile residual stress field that reached value of r0 = 476 MPa. This improvement is limited to strain rates lower than 0.5%. At higher strain rates, a cyclic plastic deformation induced martensitic phase alters furthermore the fatigue behavior by producing high cyclic strengthening of the bulk mate-rial. This phenomenon lead to a reduction in strain imposed fatigue life. It has also been established that wire brush hammering can be used as an onsite surface treatment to improve the residual fatigue life of components subjected to cyclic loading. The efficiency of this treatment is demonstrated if it is performed at a fraction of service lifetime Ni/Nr lower than 0.5

PANDANGAN PENGURUS MUI KOTA MEDAN TENTANG HUKUM SEORANG LELAKI MUSLIM MENINGGALKAN SHALAT JUM ‘AT DEMI MENJAGA KEAMANAN KENDARAAN DI MESJID

IKHTISAR Penelitian yang akan dilakukan dalam penulisan skripsi ini membahas tentang : Pandangan Pengurus Mui Kota Medan Tentang Hukum Seorang Lelaki Muslim Meninggalkan Shalat Jum’at demi menjaga Keamanan Kendaraan di Msjid, (Studi Kasus Mesjid Kota Medan Sumatera Utara). fokus studi ini adalah mengenai hukum seorang mukallaf yang dan sudah dibebankan kewajiban shalat Jum’at namun meninggalkan kewajiban shalat Jum’at demi menjaga keamanan kendaraan (tukang parkir) di beberapa mesjid kota Medan. penelitian ini berbentuk penelitian lapangan yang dilakukan di mesjid di kota Medan. Pada dasarnya hukum shalat Jum’at itu wajib, Shalat Jum’at merupakan salah satu kewajiban setiap lelaki muslim (Mukallaf) yang dilaksanakan pada hari Jum’at diwaktu zuhur, yang hanya dilaksanakan sekali dalam satu minggu. Adapun beberapa alasan tukang parkir yang meninggalkan kewajiban shalat Jum’at demi menjaga keamanan kendaraan di mesjid yakni agar kendaraan aman dan juga menjaga ketertiban terhadap orang yang sedang menjalankan kewajiban shalat jum’at, karena menurut mereka itu termasuk kemaslahatan, namun itu tidak menjadi alasan untuk meninggalkan kewajiban shalat Jum’at karena hukum shalat Jum’at itu sendiri wajib, alasan demi menjaga keamanan kendaraan di mesjid lalu meninggalkan kewajiban shalat Jum’atnya tidak dibenarkan di dalam syariat, sama saja yang meninggalkan shalat Jum’at itu berdosa karena masih banyak alternatif atau solusi lain, karena menjaga alasan tersebut bukan termasuk uzur syar’i yang telah dibenarkan oleh islam. Dengan adanya masalah seperti ini penulis tertarik menelitinya, Rumusan masalah dari penelitian ini adalah bagaimana realita penjagaan keamanan kendaraan di Mesjid kota Medan ketika berlangsungnya shalat jum’at, apa alasan tukang parkir mesjid lebih mengutamakan menjaga kendaraan dari pada melaksanakan kewajiban shalat Jum’at, dan bagaimana pendapat Aanggota Mui kota Medan tentang hal ini. Dalam mengumpulkan data penulis menggunakan cara: observasi (pengamatan), interview (wawancara). Dari hasil penulis menemukan realita tentang beberapa hasil wawancara, penulis pendapat Pengurus MUI kota Medan Sumatera Utara secara keseluruhan berpendapat bahwa mengenai hukum seorang lelaki muslim yang meninggalkan shalat Jum’at demi menjaga keamanan kendaraan di mesjid Tidak dibenarkan didalam syariat, karena itu tidak termasuk uzur syar’i, karena hukum shalat Jum’at itu wajib. sehingga penulis menyimpulkan menjaga keamanan kendaraan di mesjid ketika shalat Jum’at berlangsung sehingga meninggalkan kewajiban shalat Jum’at tidak dibenarkan, karena tidak termasuk uzur Syar’i

Komparasi Strategi, Metode, dan Media Pembelajaran Bahasa Arab Daring dan Luring di Sekolah Dasar

Abstract: The pandemic Covid-19 has brought many changes and influences in all fields. One of them is in the educational environment, which in this case is elementary school. Arabic learning which was originally done outside the network (face to face), must be carried out online (online) because there is no direct interaction between humans. This of course will raise new problems, because they occur very suddenly. The purpose of this study was to see how the comparison of offline and online Arabic learning at MI Negeri 3 Malang. The method used in this research is qualitative which will be analyzed descriptively. Sources of data collected by observation and interviews. The results of this study indicate that learning Arabic at MIN 3 Malang is better and more effective if it is done directly (offline). According to the teacher, the success of teaching Arabic online is very dependent on the strategies, methods and media the teacher chooses to deliver the material.Abstrak: Pandemi Covid-19 membawa banyak pengaruh serta perubahan disegala bidang. Salah satunya yaitu di lingkungan pendidikan, yang dalam hal ini adalah sekolah dasar. Pembelajaran bahasa Arab yang semula dilakukan di luar jaringan (tatap muka), harus dilaksanakan secara daring (online) karena tidak boleh adanya interaksi secara langsung antar manusia. Hal ini tentu akan menaikkan masalah-masalah baru, karena terjadi sangat mendadak. Tujuan penelitian ini adalah melihat bagaimana perbandingan pembelajaran bahasa Arab secara luring dan daring di MI Negeri 3 Malang. Metode yang digunakan dalam penelitian ini adalah kualitatif yang akan dianalisis secara deksriptif. Sumber data dikumpulkan dengan observasi serta wawancara. Hasil dari penelitian ini menunjukkan bahwa pembelajaran bahasa Arab di MIN 3 Malang lebih baik dan efektif jika dilakukan secara langsung (luring). Menurut sang pengajar, keberhasilan pengajaran bahasa Arab secara daring sangat bergantung pada strategi, metode hingga media yang dipilih guru dalam menyampaikan materi