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161.
We here report the construction of an E. coli expression system able to manufacture an unnatural amino acid by artificial biosynthesis. This can be orchestrated with incorporation into protein by amber stop codon suppression inside a living cell. In our case an alkyne‐bearing pyrrolysine amino acid was biosynthesized and incorporated site‐specifically allowing orthogonal double protein labeling.  相似文献   
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The subvalent nitridometalate Ba6[(Mo1–xTax)N4]N0.86 was prepared from mixtures of Mo powder with Ba, Na, and Ba2N at 600 °C in Ta ampoules. It crystallizes in space group Cmcm with a = 11.672(3), b = 10.177(2) and c = 10.8729(19) Å. Its crystal structure exhibits an orthorhombically distorted Perovskite topology with [Ba6N] building units forming the ReO3‐type lattice via common vertices, and the nitridometalate anions occupying half of the available distorted cuboctahedral interstices. [MN4] anions show statistically mixed occupancy of M by MoVI and TaV. They show no notable deviation from nitridometalate anions in known ionic nitridomolybdates and ‐tantalates, and the metrics of the [Ba6N] octahedra correspond to those found in similar subvalent compounds. The nitrogen atom position centering the [Ba6N] octahedra is underoccupied. Band structure calculations corroborate the subvalent character of the compound and the two individual anionic structural building units.  相似文献   
164.
We prove the absence of anomalous dissipation of energy for long time averaged solutions of the forced critical surface quasi-geostrophic equation in two spatial dimensions.  相似文献   
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The catalytic methanolysis of the chemical warfare nerve agents soman, sarin, and VX was investigated by using Cu or Zn complexes. Although VX withstood decontamination, the decomposition yield being around 96%, the soman and sarin deposited on different surfaces were almost fully destroyed under ambient conditions. The catalytic tests performed on a wide range of contaminated surfaces confirm the activity of the investigated catalytic systems, these complexes being suitable, from an economical point of view, for use in the formulation of a possible decomposition kit with military or civilian applicability.  相似文献   
168.
Cs2Hg27, the Mercury‐richest Amalgam with Close Relationship to the Bergman Phases By electrolyzing a solution of cesium iodide in N,N‐dimethylformamide at 2 °C on a mercury cathode the amalgam Cs2Hg27 can be synthesized. It crystallizes in an own cubic structure type (space group , a = 16.557(4) Å). The structure can be rationalized by a system of concentrical polyhedral spheres, in close analogy to the Bergman phases.  相似文献   
169.
Rare Earth Halides Ln4X5Z. Part 1: C and/or C2 in Ln4X5Z The compounds Ln4X5Cn (Ln = La, Ce, Pr; X = Br, I and 1.0 < n < 2.0) are prepared by the reaction of LnX3, Ln metal and graphite in sealed Ta‐ampoules at temperatures 850 °C < T < 1050 °C. They crystallize in the monoclinic space group C2/m. La4I5C1.5: a = 19.849(4) Å, b = 4.1410(8) Å, c = 8.956(2) Å, β = 103.86(3)°, La4I5C2.0: a = 19.907(4) Å, b = 4.1482(8) Å, c = 8.963(2) Å, β = 104.36(3)°, Ce4Br5C1.0: a = 18.306(5) Å, b = 3.9735(6) Å, c = 8.378(2) Å, β=104.91(2)°, Ce4Br5C1.5: a = 18.996(2) Å, b = 3.9310(3) Å, c = 8.282(7) Å, β = 106.74(1)°, Pr4Br5C1.3: a = 18.467(2) Å, b = 3.911(1) Å, c = 8.258(7) Å, β = 105.25(1)° and Pr4Br5C1.5: a = 19.044(2) Å, b = 3.9368(1) Å, c = 8.254(7) Å, β = 106.48(1)°. In the crystal structure the lanthanide metals are connected to Ln6‐octahedra centered by carbon atoms or C2‐groups. The Ln6‐octahedra are condensed via opposite edges to chains and surrounded by X atoms which interconnect the chains. A part n of isolated C‐atoms is substituted by 1‐n C2‐groups. The C‐C distances range between 1.26 and 1.40Å. In the ionic formulation (Ln3+)4(X?)5(C4?)n(C2m?)1?n·e? with 0 < n < 1 and m = 2, 4, 6 (C22?, C24? C26?), there are 1 < e? < 5 electrons centered in metal‐metal bonds.  相似文献   
170.
The Lanthanumiodideethanide o‐La5I9(C2) – The Orthorhombic High Temperature Modification o‐La5I9(C2) is synthesized by reaction of LaI3, La metal and graphite powder in sealed Ta containers at 850 °C < T < 900 °C. It crystallizes in the orthorhombic space group Pbca with a = 8.0247(16) Å, b = 16.887(3) Å, c = 35.886(7) Å. o‐Ce5I9(C2) is isotypic with the lattice parameters a = 7.9284(4) Å, b = 16.714(1) Å, c = 35.530(3) Å. o‐La5I9(C2) transforms at 800 °C to the triclinic low temperature modification t‐La5I9(C2). The transformation is reversible. The La atoms form trigonal bipyramids centered by C2 groups. These units are connected by iodine atoms above the faces (f), edges (e) and corners according to La5(C2)I(f)iI(e)i?i2/2I(e)i?a7/2I(e)a?i7/2. The C‐C distance in the C2 unit is 1.45(2) Å. The crystals with greenish luster are moisture sensitive.  相似文献   
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