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From an historical perspective, the chemistry of actinide ions under acidic conditions is relatively well-known, 2 and nearneutral solution chemistry has received considerable attention due to its relevance to radioactive waste isolation and disposal. 3 In contrast, actinide solution chemistry under strongly alkaline conditions, such as those found in aging waste tanks within the DOE complex, is poorly understood. Alkaline conditions can stabilize high oxidation states such as V, VI, and even VII. 4 The heptavalent oxidation state of actinide ions is rare, but has been known since the late 1960's. 5 Single crystal X-ray structures have been determined for Na 3 NpO 4 (OH) 2 ‚nH 2 O 6 and Co(NH 3 ) 6 NpO 4 (OH) 2 ‚2H 2 O, 7 which display the highly unusual tetragonal bipyramidal NpO 4 (OH) 2 3central core (I) in the solid state. However, from alkaline solution, one can also isolate infinite chains such as LiCo(NH 3 ) 6 Np 2 O 8 (OH) 2 ‚2H 2 O (II), 8 or layered solids such as MNpO 4 (M ) Cs, K) which, based on marginal Rietveld refinement (R)12.1), is reported to contain a NpO 2 3+ central core (III). 9 No simple anion of formula NpO 4 -(IV), akin to MO 4 -(M ) Re, Tc, Mn), has been observed. Based on the solid state structure of I, it has been argued that I must exist in alkaline solution. 6,7 There are no data to support this claim. We report here an XAFS study to determine the structure of Np(VII) in alkaline solution.Alkaline Np(VII) solutions (0.03 M) were prepared by bubbling O 3 through a 2.5 M NaOH solution containing NpO 2 -(OH) 2 , 10 and the resulting dark green solution was characterized by using UV-Vis-NIR spectroscopy. Solution spectra revealed absorption maxima at 410 ( ) 1350 M -1 cm -1 ) and 625 nm ( ) 385 M -1 cm -1 ), consistent with previous reports of alkaline Np(VII) solutions. 5 These solutions are stable for several months when sealed under an O 3 atmosphere. X-ray absorption measurements of these Np(VII) solutions were performed at the Np L III -edge, 11 and calibrated against a Zr foil. 12 Curve-fitting amplitudes and phases were calculated with FEFF6. 13

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A simple preparation of N-substituted 3-pyrroline boromic esters from primary amines is described. The Suzuki-Miyaura coupling of these heterocycles with aryl halides proceeds in good yields. Alternatively, oxidation with DDQ or MnO 2 gives the corresponding pyrroles, which can be also engaged in subsequent palladium cross-coupling reactions.

I. AbstractA high performance 65 nm SOI CMOS technology is presented. Dual stress liner (DSL), embedded SiGe, and stress memorization techniques are utilized to enhance transistor speed. Advanced-low-K BEOL for this technology features 10 wiring levels with a novel K=2.75 film in selected levels. This film is a SiCOH-based dielectric optimized for stress to enable integration for enhanced performance. The resulting technology delivers pFET and nFET AC switching on-current of 735 µA/um and 1259 µA/um respectively, at an off-current of 200 nA/um (V dd =1.0 V), and 6% reduction in interconnect delay. Process yield is demonstrated on a SRAM cell with size of 0.65 µm 2 . II. Technology DescriptionThe major ground rules used in this technology are equivalent to our 65-nm-baseline technology which utilizes DSL for enhanced performance [1]. DSL is a process integration flow that combines tensile and compressive stress silicon nitride liners on nFET and pFET devices respectively, resulting in increased channel strain and performance for both. Fig. 1 shows our baseline flow with additional enhanced strain process steps. Specifically, the embedded SiGe process is implemented with epitaxial SiGe growth in cavities etched into the source/drain areas of the pFETs. The nFETs are covered with a nitride hardmask during recess etch and epitaxial growth of SiGe in the pFET areas. Photolithography is utilized to mask the nFET areas while the hardmask is etched into a spacer in the pFET areas. This spacer defines the proximity of the SiGe to the channel area and prevents SiGe growth on the pFET polysilicon gate electrode. A stress memorization technique (SMT) is implemented for the nFETs where increased tensile strain was achieved by the deposition of a stress dielectric film and subsequent thermal anneal.The remaining process flow steps are equivalent to our baseline CMOS process, except for a modified Ni silicide process that achieves improved contact and stability on SiGe. This is followed by DSL implementation in the middle-of-line (MOL) [2]. A cross-sectional TEM image of a completed device is shown in Fig. 2, also shown is an AFM image of the surface morphology of the source/drain area of the pFET demonstrating a smooth RMS roughness value of 0.11 nm. The advanced-low-K dielectric film used in the BEOL interconnect levels is based on the K=2.75 material previously discussed [3]. This film has been optimized for lower permittivity (K=2.75) and stress. Extendibility of the film into both 2x and 4x fatwire levels has been demonstrated. III. FEOL Performance ResultsA plot of the Ion-Ioff characteristics is shown in Fig. 3 along with the transistor characteristics in Fig. 4 at 1.0 V Vdd, where the threshold voltage roll-off is well-behaved down to 30 nm gate length, and sub-threshold swing is maintained at ~110 mV/dec (Fig. 5-6). pFET AC switching on-current of 735 µA/µm at off-current of 200 nA/µm with a corresponding DC on-current of 700 µA/µm was achieved. For the nFET, the AC switching on-current was 1259 µA/µm and the DC on-cur...

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Aus RBBr2 und Na/K‐Legierung erhält man ebenso wie zweistufig aus B4R4 und Na/K‐Legierung und nachfolgender Einwirkung von HCl das Tetraboran B4H2R4 (R = tBu). Aus NMR‐Daten und einer ab‐initio‐Rechnung für die Stammverbindung B4H6 sowie für B4H2Me4 läßt sich eine B4‐Tetraederstruktur 1 ableiten, in der zwei gegenüberliegende Kanten durch je ein H‐Atom überbrückt sind (D2d‐Symmetrie). Im Tetraboran B4H2R4 kann man mit Lithium in Tetrahydropyran (L) ein Brücken‐H‐Atom gegen die Gruppierung LiL2 austauschen. (L2Li)B4HR4 wurde durch Einkristall‐Röntgenstrukturanalyse charakterisiert.