IR absorption spectra of N-substituted tetrazoles

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 54, No. 6, pp. 923–933, June, 1991.     

Computational design and screening of promising energetic materials: Novel azobis(tetrazoles) with ten catenated nitrogen atoms chain

Density functional theory methods were used to study on 2 N10 compounds, 1,1′‐azobis(tetrazole) and 1,1′‐azobis(5‐methyltetrazole). We systematically investigated 10 novel substituted azobis(tetrazoles) with 10 catenated nitrogen atoms and various energetic groups (–CF₃ 1 , –C(NO₂)₃ 3 , –N₃ 5 , –NH₂ 6 , –NHNH₂ 7 , –NHNO₂ 8 , –NO₂ 9 , –OCH₃ 10 , –OH 11 , –ONO₂ 12 ). The optimized geometry, frontier molecular orbitals, electrostatic potential, Infrared and nuclear magnetic resonance spectrum were calculated for inspecting the molecular structure and stability as well as chemical reactivity. The effects of different substituents on the density, enthalpy of formation, heat of explosion, detonation velocity and pressure, and sensitivity of the azobis(tetrazole) derivatives have been investigated. Compound 9 with nitro was found to have remarkable detonation performances (D = 9.61 km/s, P = 42.14 GPa), which are close to the excellent explosive CL‐20. Results show that compounds 1 , 3 , 4 , 7 , 9 , 11, and 12 have high potential to replace RDX. It is surprising that compounds 1 , 3 , 9, and 12 possess better energetic properties than HMX. These novel substituted azobis(tetrazoles) with unique N10 structure may be promising candidates of HEDMs with outstanding performance and acceptable sensitivities.     

Fe(II) spin-crossover compounds based on the extremely versatile ligand system of 1-substituted tetrazoles: a comparative study

Bulk measurements of magnetic susceptibility χ and ⁵⁷Fe-Mössbauer spectroscopy were used to investigate the low spin (LS) to high spin (HS) transition caused by temperature changes for different mono- and polynuclear Fe(II) complexes based on the extremely versatile class of 1-substituted tetrazoles. The influence of length and rigidity of different terminating and bridging ligands is shown.     

A new multipurpose diffractometer PILATUS@SNBL

The diffraction beamline BM01A at the European Synchrotron Radiation Facility (CRG Swiss–Norwegian beamlines) has been successfully operational for 20 years. Recently, a new multifunctional diffractometer based on the Dectris Pilatus 2M detector has been constructed, commissioned and offered to users. The diffractometer combines a fast and low‐noise area detector, which can be tilted and moved horizontally and vertically, together with flexible goniometry for sample positioning and orientation. The diffractometer is controlled by a user‐friendly and GUI‐based software Pylatus which is also used to control various auxiliary equipment. The latter includes several heating and cooling devices, in situ cells and complimentary spectroscopic tools.     

Spatial screening solitons as particles

Photorefractive spatial screening solitons are treated as rays using geometrical optics. The ray picture is transformed into a classical mechanics picture, in which solitons move self-consistently as particles in a potential created by the induced change in the refractive index. The Hamiltonian equations of motion are integrated to yield trajectories that agree with the optical center-of-mass trajectories. The motion in the transverse plane is found to be not central and the orbits are not closed, preventing the spiraling of solitons.     

Fianite: A multipurpose electronics material

Fianite-zirconium dioxide, stabilized by yttrium (YSZ) has a unique combination of physical and chemical properties that made it a very promising material for a wide range of applications. In this work, we consider the use of fianite as a bulk substrate and buffer layer for A ^III B ^V epitaxy, and as an antireflection and protective coating for photo detectors and solar cells.     

Real-time and online screening method for materials emitting volatile organic compounds

In the semiconductor industry, volatile organic compounds (VOCs) in the cleanroom air work as airborne molecular contamination, which reduce the production yield of semiconductor chips by forming nanoparticles and haze on silicon wafers and photomasks under ultraviolet irradiation during photolithography processes. Even though VOCs in outdoor air are removed by gas filters, VOCs can be emitted from many kinds of materials used in cleanrooms, such as organic solvents and construction materials (e.g., adhesives, flame retardants and sealants), threatening the production of semiconductors. Therefore, finding new replacements that emit lower VOCs is now essential in the semiconductor industry. In this study, we developed a real-time and online method to screen materials for developing the replacements by converting VOCs into nanoparticles under soft X-ray irradiation. This screening method was applied to measure VOCs emitted from different kinds of organic solvents and adhesives. Our results showed good repeatability and high sensitivity for VOCs, which come from aromatic compounds, some alcohols and all tested adhesives (Super glue and cleanroom-use adhesives). In addition, the overall trend of measured VOCs from cleanroom-use adhesives was well matched with those measured by a commercial thermal desorption–gas chromatography–mass spectrometry, which is a widely used off-line method for analyzing VOCs. Based on the results, this screening method can help accelerate the developing process for reducing VOCs in cleanrooms.     

Metal-iodide cyclodextrins as model quasi-one-dimensional compounds

The synthesis and electrical and magnetic properties of two metal-iodide cyclodextrin compounds are described. Both Ba and Fe ions were added to the α-cyclodextrins to form needle-shaped single crystals. The compounds have electrical conductivities of about 10^?9 (ω cm)^?1 at room temperature. The Ba compound is diamagnetic but the Fe compound shows Curie-Weiss behavior in its susceptibility between 1.5 and 108 K, with an effective moment of 4.5 μ_B and a Weiss temperature of ?5.6 K. The results indicate antiferromagnetic interactions between Fe(II) ions. A discussion is given of some problems associated with synthesizing quasi-one-dimensional conductors or magnetic compounds, using the cyclodextrins as a basis.     

Noise as reliability screening for semiconductor lasers

The low-frequency electrical noise in semiconductor lasers is measured and used for device-reliability screening, which is a sensitive and non-destructive method. In the experiment, we developed some approaches to improve the validity of reliability screening by using noise criteria. A new method of determining the threshold level of noise criteria is given. The experimental results show that this method is effective. Received: 26 September 2002 / Revised version: 28 January 2003 / Published online: 9 April 2003 RID="*" ID="*"Corresponding author. Fax: +86-431/462-7013, E-mail: huguijun@sina.com     

Synthesis of Quinolone Substituted Pyrazoles,Isoxazoles and Pyridines as a Potential Blue Luminophors

Series of quinolone C₃-substituted pyrazolines, isoxazolines, pyridines and pyrimidines were synthesized in good yields by the cyclocondensation reactions of 1, 2-unsaturated ketones and hydrazines, hydroxylamine hydrochloride and dimedone respectively. The quinolone derivatives (3, 5 and 7) were synthesized and further studied for their photophysical properties. High absorption and quantum yield are found for N₁-phenyl and C_3,4-dimethoxy substituents on phenyl ring (3h). Energy optimization by PM6 methods showed high stability required for selection of suitable candidates to be use as future blue emitters.     

The trigeneration cycle as a way to create multipurpose stationary power plants based on conversion of aeroderivative turbofan engines

A schematic cycle is considered, and thermodynamic analysis is performed to substantiate the possibility of creating multipurpose industrial power plants, operating on a trigeneration cycle, based on production-type turbofan engines.     

Efficiency of high-molecular compounds used as surface-active substances

The dispergation of metal shavings mixed with a destructible high-molecular compound is demonstrated to intensify the grinding process, stimulate metal plasticizing, and protect activated powders against oxidation due to the metal surface plating with organic films.     

基于PC机的一种多功能声显微镜及可视化技术的研究

近来研制成功了一种基于ＰＣ机、我们称为“ＴＨＳＡＭＭ”型的多功能声显微镜。在ＰＣ机内插入采样率１ＧＳＰＳ的超高速Ａ／Ｄ卡和信号产生和接收卡,利用软件完成信号检测、处理、显示功能。仪器工作频率为１－１００ＭＨｚ;在检测样品时,同时多层显示Ａ、Ｂ、Ｃ扫描结果。根据声学理论、Ｍａｒｃｈｉｎｇ Ｃｕｂｅ等值面抽取方法和ＯｐｅｎＧＬ技术完成了三维数据的可视化处理,显示样品的内部三维结构。该系统已成功应用于多     

Influence of valence band states on the core hole screening in lanthanide perovskite compounds

Investigation on core level and valence band photoelectron spectra of lanthanide perovskite samples (Ag _x La_1–x CoO₃;x<0,3) and reinvestigations of metallic lanthanum and La-oxide layers are reported. Differences in preparation method during perovskite formation are leading to different quality of sample purity and different electronic properties. This could be followed by changes in the density of states near the Fermi energy. On the other hand the screening mechanism after ionization of a La 3d core hole is affected by the relative energy position of occupied valence band states with respect to the empty La 4f ^* level in the core ionized state. Changes in La 3d line profile are discussed as changes in multi electron processes (e.g. shake up or energy gain) during photoionization. We attribute the two electron process during photoemission of La 3d electrons to the well screened energy gain transition in LaCoO₃, whereas the two electron process results in a shake up transition in La₂O₃ and La(OH)₃.     

Time-of-flight system for the multipurpose detector (MPD)

A conceptual design for a multipurpose detector (MPD) [1] is proposed for the study of hot and dense barony matter in collisions of heavy ions over the atomic mass range A = 1–197 at center-of-mass energies of up to 11 GeV (for Au⁷⁹⁺). The MPD experiment is scheduled to be performed at a future JINR accelerator complex facility for heavy ions, the Nuclotron-based Ion Collider Facility (NICA), which is designed to reach the required parameters with an average luminosity of L = 10²⁹ cm⁻² s⁻¹. Identification of charged hadrons (PIDs) at intermediate momenta (0.1–2 GeV/c) is achieved via time-of-flight (TOF) measurements. As a base element of the TOF detector, we consider a 10 gap MRPC with a strip or pad readout. Results from an MRCP prototype test are presented.     

The architecture of a multipurpose fringe pattern analysis system

A review of the advantages and disadvantages of analytical phase measurement methods of automatic fringe patterm analysis is given. The pros and cons for their applications due to the complexity of an interferogram, the accuracies required and the type of quantity measured are considered. The architecture of the system which enables a proper choice between the Fourier transform method, temporal and spatial phase-shifting methods is described. The modular structure of the software gives the possibility of getting the results in the most efficient way.     

Fluorescence of Substituted Tetraazabacteriochlorin

The spectral, energy, and polarization characteristics of the fluorescence of substituted tetraazabacteriochlorin in solution have been obtained. On the basis of the polarization spectrum, the electronic absorption spectrum is interpreted. The quenching of the fluorescence of bacteriochlorin on substitution of methine bridges by aza bridges is noted.