Properties of CsI(TI) — Renaissance of an old scintillation material

CsI(TI) is an interesting material for calorimeters in high energy physics. Properties of this material are reported.     

Electrochemical impedance spectroscopy on porous electrodes

Electrochemical d.c. and a.c. measurements have been carried out on porous Raney nickel in H₂-saturated 0.1 M, 1 M, and 6 M NaOH solutions atT=303 K and 333 K using rotating-disc and static-plaar electrodes. For comparison, measurements were also performed on graphite-cloth and graphite-felt electrodes. From polarization curves and current transients obtained in the potential range of the hydrogen evolution and hydrogen oxidation reactions the dependence of the electrocatalytic activity of Raney nickel on the prepolarization conditions was studied. Impedance spectra in the frequency range 1 mHzf 10 kHz were used to determine the characteristic pore parameters and to identify the kinetic behaviour of the porous electrodes by application of transfer function analysis using non-linear fit routines.     

Simple N‐Heterocyclic Carbenes as Ligands in Ullmann‐Type Ether and Thioether Formations

A simple N‐heterocyclic carbene (NHC) derived from 1‐methyl‐3‐ethylimidazolium tetrafluoroborate was found to be an efficient ligand for a range of copper‐catalyzed cross‐coupling reactions, leading to the formation of aromatic ethers and thioethers.

     

Nonlinear model predictive control for dividing wall columns

Dividing wall columns (DWCs) are practical, effective, and promising among distillation process intensification technologies. Nonlinear model predictive control (NMPC) schemes are developed in this study to control the three-product DWCs. As these systems are intensely interactive and highly nonlinear, NMPC may be more suitable than the traditional PI control. The model is established based on Python and Pyomo platforms. As the original mathematical model of the column section is ill-posed, index reduction is used to avoid a high-index differential-algebraic equation (DAE) system. The well-posed index-1 system after index reduction is employed for the steady-state simulation and dynamic control in this study. Case studies with three DWC configurations to separate the mixture of ethanol (A), n-propanol (B), and n-butanol (C) show that the NMPC performs very well with small maximum deviations and short settling times. This demonstrates that the NMPC is a feasible and very effective scheme to control three-product DWCs.     

Theoretical fitting characteristics of typical soft contact lens designs

Purose

To calculate theoretical fitting success rates (SR) for a range of typical soft contact lens (SCL) designs using a mathematical model.

Zur anodischen auflösung von reineisen im bereich zwischen aktivem und passivem verhalten

The kinetics of anodic iron dissolution in sulphate ions containing solutions, which are free of oxygen, are investigated in a over potential range between active and passive states of the metal. The measurements were carried out on a rotating disk electrode in the pH-range between 3·5 and 5·5 using the potentiostatic triangular voltage sweep method under quasi-steady-state conditions. The measured current density-potential curves show two current maxima. At relatively low anodic overvoltages, i.e. before the maxima I is reached, the used recrystallized iron dissolves in the active state corresponding to the consecutive (Bockris-) mechanism. At high anodic overvoltages the passive state arises after passing the maxima II. In the transition range, i.e. in the potential range of the maximum I, a second mechanism of iron dissolution is discussed. This mechanism takes place parallel to the consecutive one. An intermediate [Fe (OH)₂]_ads will be formed, which dissolves in a following rate-determining chemical step or is changed in an oxide phase respectively.     

TBM Leistungsprognose mit Modellschneidversuchen

A scaled rock cutting test developed at the Chair of Subsurface Engineering, Montanuniversität Leoben, is presented. It is designed as an attachment for hydraulic presses commonly available in rock mechanics laboratories. Rotating disc cutters are used to cut rock samples several times with the possibility to adjust indentation depth and spacing. Standard sample sizes which are available in early phases of a tunnelling project are used in order to enable this test to be used for TBM performance prediction. The results are compared to geotechnical standard tests and full scale linear cutting tests. It is shown that the results of scaled rock cutting tests are excellent input parameters for TBM performance prediction.     

Analysis and design of current regulators using complex vectors

The analysis and design of current regulators for multiphase AC loads in AC machines is presented using complex vector notation. The use of complex vector notation provides a way of comparing the performance of controller topologies through their complex vector root locus and complex vector frequency-response functions. Limitations in the performance of the synchronous frame proportional plus integral current regulator are outlined and several ways of improving its performance are suggested and investigated     

家具与衣服

Couch Sleeper、Home Traveller、Lingerie Locker是Anne Lorenz在Karlsruhe艺术设计学院时毕业作品的一部分。可能因为女性天生对衣服就有很高的敏锐度,Anne Lorenz一直着迷于研究家具与衣物之间的关系,并不断探讨它们之间的形式与功能。