Regioselective lithiation of 1‐benzylpyrazole derivatives: Synthesis of amides derived from pyrazole

A series of brominated 1‐benzylpyrazoles were deprotonated at the pyrazole 5‐position or the benzylic position on treatment with lithium diisopropylamide in tetrahydrofuran at low temperature. The obtained organolithium intermediates were subjected to reaction with Me₃SiCl, t‐BuNCO, ClCONEt₂ or ClCON(i‐Pr)₂ affording the respective silanes or amides after hydrolysis.     

Phenotyping Metastatic Brain Tumors Applying Spectrochemical Analyses: Segregation of Different Cancer Types

Metastatic brain tumors represent a significant proportion of tumors identified intraoperatively. A rapid diagnostic method, circumventing the need for histopathology studies, could prove clinically useful. As many spectroscopic studies have shown ability to differentitate between different tumor types, this technique was evaluated for use within metastatic brain tumors. Spectrochemical approaches [Raman and attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) spectroscopy] were applied to determine how readily they may identify the primary site for the metastatic tumor. Metastases were from primary adenocarcinomas of lung (n?=?7) and colorectum (n?=?7), and for comparison, metastatic melanoma (n?=?7). The objective was to determine if Raman or ATR-FTIR spectroscopy could delineate the origin of the primary tumor. The results demonstrate that there are marked similarities between the two adenocarcinoma groups and whilst Raman and ATR-FTIR can distinguish the three groups with limited success, classification accuracy is greatly improved when combining the adenocarcinoma groups. The use of such techniques in the clinical setting is more likely to be found intraoperatively, determining the presence of a tumor and suggesting the tumor class; however, traditional histopathology would still be needed to identify the primary origin of the tumor.     

New Organorhodium and -Iridium Compounds of Iminophosphoranylmethanes

Abstract

The synthesis and structure of new metallacyclic compounds of Rh(I) and Ir(I) containing bidentate mono- and bis(iminophosphoranyl)methane or -methanide ligands and their reactions with CO, phosphine and HCl are described.     

Analysis of questioned documents: A review

During the last years (2000–2014), many publications concerning the forensic analysis of questioned documents have been published, and new techniques and methodologies are nowadays employed to overcome forensic caseworks. This article reviews a comprehensive collection of the works focused on this issue, including dating studies, the analysis of inks from pens and printers, the analysis of paper, the analysis of other samples related to questioned documents and studies on intersecting lines. These sections highlight the most relevant analytical studies by a wide range of analytical techniques. Separation and spectrometric techniques are critically discussed and compared, emphasizing the advantages and disadvantages of each one. Finally, concluding remarks on the research published are included.     

Flow measurements inside a heated multiple rotating cavity with axial throughflow

This paper discusses experimental results from a multiple cavity test rig representative of a high pressure compressor internal air system. Measurements of the axial, tangential and radial velocity components are presented. These were made using a two component, laser doppler anemometry (LDA) system for a range of non-dimensional parameters representative of engine conditions (Re up to 4 × 10⁶ and Re_z up to 1.8 × 10⁵). Tests were carried out for two different sizes of annular gap between the (non-rotating) drive shaft and the disc bores.

The axial and radial velocities inside the cavities are virtually zero. The size of the annular gap between disc bore and shaft has a significant effect on the radial distribution of tangential velocity. For the narrow annular gap (d_h/b = 0.092), there is an increase of non-dimensional tangential velocity V/Ωr with radial location from V/Ωr < 1 at the lower radii to solid body rotation V/Ωr = 1 further into the cavity. For the wider annular gap (d_h/b = 0.164), there is a decrease from V/Ωr > 1 at the lower radii to solid body rotation further into the cavity. An analysis of the frequency spectrum obtained from the tangential velocity measurements is consistent with a flow structure in the r– plane consisting of pairs of contra rotating vortices.     

Écoulement turbulent dans une cavité rotor–stator fermée de grand rapport d'aspect

A direct numerical simulation is combined with laboratory study to describe the turbulent flow in an annular high speed rotor–stator cavity. Comparisons are made for a turbulent flow characterized by a Reynolds number $\mathit{Re}=\Omega R_2^2/\nu =9.5\times {10}^4$ in a shrouded cavity of large aspect ratio $G=(R_2?R_1)/h=18.32$, where $R_1$ and $R_2$ are the inner and outer radii of the rotating disk, and h is the inter-disk space. A close agreement is found between the computed results and the experimental data for the mean and turbulent fields.? To cite this article: S. Poncet, A. Randriamampianina, C. R. Mecanique 333 (2005).     

二极管激光阵列波长光束组合实现20W输出

基于波长光束组合(WBC)技术,利用光栅衍射和外腔反馈,将二极管激光阵列(LDA)发光单元锁定在不同的波长上,以近似平行光束沿光栅的-1级衍射方向组合输出,改善LDA输出光束质量.实验中采用发光单元宽度为100μm、周期为500μm及由19个单元构成的l cm普通商用LDA,在连续运行最大注入电流为60.6A、自由运转输出功率为49.8 W时,获得功率为20.1 W的组合光束稳定输出,其光谱宽度为15 mm,对应的远场发散角由约70 mrad变为1.66 mrad,改善后的光束质量因子M2x.y约为32,与单个发光单元的光束质量相当.