Triggered Marx generators for the industrial-scale electroporation of sugar beets

Electroporation is a method to induce pores in the membranes of biological cells by applying an electric field. During the last few years, some research and development has been done for sugar beets to transfer this method from the laboratory into the industrial scale in order to replace the thermal denaturation process. High-efficiency pulsed electric fields with short pulse durations are applied to the beets as a whole. This paper deals with some aspects concerning the electrode geometry and a new trigger concept for the Marx generators used to create the required electric fields.     

Practical aspects of the ventilation of high-speed developing tunnels in hot working environments

The excavation of ramps and tunnels often requires high-speed development with [or without] the use of high-energy mining equipment such as loaders, dump trucks, TBMs and roadheaders. This highspeed development creates a challenge in terms of providing a safe and productive working environment. For example, heat from continuously exposed surrounding rock, heat from broken rock, heat generated by mining equipment, potential inflows of hot ground water, pollution from associated diesel equipment, and the distance of the advancing face from fresh through-ventilation all have to be taken into account when designing ventilation systems for high-speed ramp and tunnel developments. This paper discusses methods of achieving acceptable environments at the face and along the length of the tunnel. The methodology has been successfully implemented in the development of long [up to 20 km] TBM drives in the Lesotho Highlands Project and in mining projects in hot rock using drill-and-blast methods as well as in mechanised methods using continuous miners and roadheaders. The determination of heat loads includes calculation of the heat flow within the surrounding rock, evaluation of the operating cycle of the equipment and the contribution to the overall heat load of the broken rock as it travels out of the tunnel. The determination of heat loads from surrounding rock in new tunnels required a modification of the algorithms generally used for established excavations. The paper also examines the use of, for example, mobile duct and fan systems to ensure that fresh air is delivered to the specific areas where workers are located.     

Experiment planning using high-level component models at W7-X

The superconducting stellarator Wendelstein 7-X (W7-X) is a fusion device, which is capable of steady state operation. Furthermore W7-X is a very complex technical system. To cope with these requirements a modular and strongly hierarchical component-based control and data acquisition system has been designed.The behavior of W7-X is characterized by thousands of technical parameters of the participating components. The intended sequential change of those parameters during an experiment is defined in an experiment program. Planning such an experiment program is a crucial and complex task. To reduce the complexity an abstract, more physics-oriented high-level layer has been introduced earlier. The so-called high-level (physics) parameters are used to encapsulate technical details.This contribution will focus on the extension of this layer to a high-level component model. It completely describes the behavior of a component for a certain period of time. It allows not only defining simple value ranges but also complex dependencies between physics parameters. This can be: dependencies within components, dependencies between components or temporal dependencies.Component models can now be analyzed to generate various views of an experiment. A first implementation of such an analyze process is already finished. A graphical preview of a planned discharge can be generated from a chronological sequence of component models. This allows physicists to survey complex planned experiment programs at a glance.     

同步辐射近常压光电子能谱及其应用

介绍了同步辐射近常压光电子能谱的基本概念、发展历程以及该技术的装置和原理。列举了几个近常压光电子能谱的应用领域。该技术填补了超高真空和真实条件下压强上的空白,在原位研究表面化学变化、催化反应,腐蚀以及电化学过程上有着很大的优势。     

Titanocene‐Catalysed Enantioselective Opening of meso‐Epoxides

A comparison of different titanium catalysts in the enantioselective opening of meso‐epoxides has been carried out. The best catalyst is readily available in both enantiomers from menthol and allows for a highly enantioselective reaction.