Synthesis and Crystal Structure of Mixed-Ligand Ni(II) Complex of N-(1-Phenyl-3-methyl-4-benzylidene-5-pyrazolone) p-Nitrobezoylhydrazide and Pyridine

A novel mixed-ligand nickel complex, [Ni(PMBP—PNH) (Py)₃], [PMBP—PNH=N-(1-phenyl-3-methyl-4-benzylidene-5-pyrazolone) p-nitrobezoylhydrazide; Py = pyridine], has been synthesized by the hydrothermal method and characterized by elemental analysis, IR spectrum, thermal analysis, and single-crystal X-ray diffraction. The X-ray diffraction reveals that the nickel (II) ion in the title complex is in a slightly distorted octahedral arrangement of the ONO donor atoms of primary ligand PMBP-PNH and three N-donor atoms in the secondary ligand pyridine.     

提高普通低碳钢冷镦性能的工艺研究

本文分析比较了普通低碳Q195钢与冷镦钢生产工艺、性能组织等情况,对武钢目前生产的Q195钢进了取样冷镦试验,并进行了不同的控冷工艺轧制试验.提出在武钢目前炼钢生产条件下,采用适当的轧制工艺,完全可以用普通低碳Q195钢代替部分铆螺钢.     

Modulation des flammenspektrometrischen Signals mittels intermittierender Probenzufuhr zur Flamme

Zusammenfassung An Stelle eines Choppers wird zur Modulation des flammenspektrometrischen Signals die Probenflüssigkeit periodisch der Flamme zugeführt (intermittierende Zerstäubung). Es wird zunächst über die beobachtete Eigenmodulation der Zerstäubung berichtet und danach über die intermittierende Zerstäubung mit Frequenzen bis zu 50 Hz. Anschließend wird an Hand von Beispielen gezeigt, daß sich die intermittierende Zerstäubung als besonders vorteilhaft in der Absorptions-Flammenspektrometrie erweist. Wird das Gleichlicht des Hintergrundstrahlers mittels der intermittierenden Zerstäubung in der Flamme moduliert und ein Wechselstromverstärker verwendet, so fallen der 0- und 100%-Durchlässigkeitspunkt zusammen. Bei der Registrierung über die Wellenlänge werden dann nur solche Linien angezeigt, welche in der Flamme das eingestrahlte Licht absorbieren.

---

Summary For modulating the flame spectrometric signal without using a chopper the sample is introduced into the flame periodically (intermittent atomisation). First, the observed self-modulation of the atomisation is described and subsequently the intermittent atomisation with frequencies up to 50 cps. Some examples demonstrate that intermittent atomisation proves to be especially advantageous in absorption flame spectrometry. When modulating the light of the dc-operated line source by means of intermittent atomisation and using ac-amplification of the modulated signal the 0- and 100%-transmittance points of the transmittance scale are the same. When scanning over the wave length only such lines are detected which absorb the light of the background source.

---

---

Der Fa. Siemens-Reiniger Werke AG., Erlangen, und insbesondere Herrn Ing. Engel danken wir auch an dieser Stelle für die leihweise Überlassung des Flüssigkeitsstrahloscillographen Cardirex 31 B. — Herrn K. RÜdiger danken wir für die wertvollen Hinweise und für die Durchführung der Werkstattarbeiten.     

Fluorine-Containing Organozinc Reagents Part 1 A Simple Synthesis of 2,2-Dichloro-3,3,3-trifluoropropanol

The title compound 1 , which can be regarded as a synthetic equivalent of substituted 1,1,1-trifluoroacetone 2 , is prepared by Zn-induced reductive addition of 1,1,1-trichloro-2,2,2-trifluoroethane ( 3 ) to formaldehyde ( 4 ). A brief survey of the scope of this C? C-bond formation leading to a variety of new CF₃-containing synthetic building blocks is also given.     

Crystal structure and photochromism of 1-phenyl-3-methyl-4-benzyl-5-one-pyrazole S-methyl thiosemicarbazone

A new organic photochromic compound containing pyrazolone-ring photochromic functional unit: 1-phenyl-3-methyl-4-benzyl-5-one pyrazole S-methyl thiosemicarbazone (PMBP-smtsc) was synthesized. The photochromic properties and photochemical kinetics of PMBP-smtsc have been studied by UV reflectance spectra under irradiation of 365 nm light. The crystal structure analyses of photocolored product show the photochromism is due to the photoisomerization from enol form to keto form through an intermolecular proton transfer.     

Cation electrochemical stability in chloroaluminate ionic liquids

The electrochemical stability of 10 organic cations, which can be used in ionic liquids (IL), was investigated as solutes in acetonitrile (ACN). The stability of three of the salts, BenMe2EtNCl (salt III), 1-butyl-2-methyl pyrrolidium chloride (salt VI), and its structural isomer, BuMe2ProNCl (salt VII), were also compared in chloroaluminate ILs. The chloroaluminate ILs of salts VI and VII are investigated for the first time. The NaCl-neutralized ILs of salts VI and VII have melting points of 43.2 and 3.7 degrees C, respectively. The benzyl-substituted cation, salt III, was more easily reduced in ACN or as the neutral chloroaluminate IL than the alkyl-substituted cation, salt VII, due to the better leaving ability of the benzyl group. Mass spectroscopy measurements before and after electrolysis on the benzyl-substituted solutions confirmed that reduction involves the loss of an alkyl group. In ACN, salt VI was found to be the most difficult to reduce (1 mA/cm2 at -2.09 V) due to its cyclic structure. However, in the chloroaluminate IL, the pyrrolidinium cation was more easily reduced than salt III or its isomer, salt VII, resulting in an insoluble black deposit. This is consistent with the mass spectrometry data, which do not show formation of low-molecular-weight products, as in the reduction of salts III and VII. The IL of salt VII was the most stable in the presence of sodium. Sodium ions could be reduced and reoxidized with a maximum Coulombic efficiency of 94.1% versus 87.2% for salt VI. Reduction of the pyrrolidinium cation produces insoluble products, most likely through opening of the cyclic ring, and an inferior medium for sodium ion reduction compared to the benzyl- and butyl-substituted cations, even though reduction of the cation occurs at a more negative potential in acetonitrile.     

Stereospecific cyclopropane ring-opening of petrosterol. A possible biomimetic process.

Acid-catalyzed isomerization of the petrosterol side chain ($\text{1}$) proceeds stereospecifically to yield the naturally occurring 26-dehydro-25-epiaplysterol side chain ($\text{2}$); in addition, a 1.5-hydride shift leading to 22-dehydro-25-epiaplysteryl acetate ($\text{3}$) has also been observed.