摘要：It is known that the slabs on soil constitute one of the most difficult types of structures despite their apparent simplicity. The objective of this paper is to give a general survey of the design of ground supported slabs with the interposition of a suitable subbase. A solution is proposed with the following characteristics： （1） complete suppression of joints; （2） conventional reinforcement with meshes in the upper and lower fiber of the slab in order to confront and distribute cracking that is caused by hindrance of free contractions and expansions; （3） effective confrontation of problems of bulging. The proposal is in effect on one hand for industrial floorings and on the other hand for concrete pavings with large durability requirement.

摘要：The commercialization of proton exchange membrane fuel cells(PEMFCs)could provide a cleaner energy society in the near ***,the sluggish reaction kinetics and harsh conditions of the oxygen reduction reaction affect the durability and cost of *** previous reports on Pt-based electrocatalyst designs have focused more on improving their activity;however,with the commercialization of PEMFCs,durability has received increasing ***-depth insight into the structural evolution of Pt-based electrocatalysts throughout their lifecycle can contribute to further optimization of their activity and *** development of in situ electron microscopy and other in situ techniques has promoted the elucidation of the evolution *** mini review highlights recent advances in the structural evolution of Pt-based *** mechanisms are adequately discussed,and some methods to inhibit or exploit the structural evolution of the catalysts are also briefly reviewed.

摘要：This study aims to reveal the mechanism that how the content of steel fibers and strength grades affect the macro performance of the ultra-high performance fiber reinforced cementitious composite （UHPFRCC） and to study the UHPFRCC durability under the combined effect of loads and environments. Three types of high and ultra-high performance fiber reinforced cement composites with different strength grades （100, 150, 200 MPa） and different steel fiber volume fractions （0%, 1%, 2%, 3%） are prepared. The main properties of mechanical performance and short-term durability are studied. A preloading frame is designed to apply a four- point load external flexural stress with a stress selection ratio of 0.5 for UHPFRCC150 specimens. The results show that the growth in strength grade with a proper content of steel fiber greatly increases the strength and toughness of the HPFRCC and the UHPFRCC while decreasing the dry-shrinkage ratio. For the loaded specimens, the existence of steel fiber can reduce the negative influence of tensile stress on the Cl- penetration resistance of the UHPFRCC in addition to improving its ability to resist the freeze-thaw damage.

摘要：Selecting the right design of bioreactors is crucial for guaranteeing the reproducibility of bioprocesses. Up to now, conventionally designed bioreactors consist typically of melted or clamped joints. Since melting of borosilicate glass leads to large deformed areas along the joint, the desired geometric reproducibility is not ensured. Moreover, clamping complicates and greatly restricts the bioreactor design. Bonding, however, is advantageous in that it does not alter the material joined and it is easy to use. Furthermore, it has been recently shown that specially developed glass bonding techniques withstand multiple autoclaving cycles. The current research investigated practice-relevant parameters influencing the lifespan of epoxy-or (urethane) acrylate-bonded glass bioreactors. Hereby, the influence of cleaning and sensitivity to fermentation compounds (ethanol and acetic acid) was quantified using glass-glass and glass-stainless steel specimens. Whereas cleaning did not adversely affect the durability of glass bonds, high concentrations of the fermentation compounds ethanol and acetic acid resulted in accelerated corrosion and subsequent bond failure. Moreover, no effect of eight different epoxy and (urethane) acrylate adhesives was observed on selected model organisms Escherichia coli K12 and Hansenula polymorpha wild type. Another objective of this study was to refine the design of two small-scale bioreactors (ca. 250 mL) by replacing clamps and melted joints by adhesive joints. It was found that the bonded bioreactors yielded a higher geometric reproducibility than that of conventional melted or clamped ones. In conclusion, bonded glass joints greatly enhance the geometric reproducibility of bioreactors and, in turn, the reproducibility of bioprocesses. As glass bonding is easy to handle, it opens up new opportunities to design bioreactors that had been previously too expensive and complicated.