Development of Sustainable Production Technology of Free-Form Concrete Panels Using a Multi-Point Press CNC Machine

Maintaining shape accuracy in the production of concrete panels of free-form buildings is time-consuming and costly. In addition, disposable molds used for free-form panels are not sustainable. Such problems can be solved by developing a suitable computerized numeric control (CNC) machine that can produce an accurately shaped reusable form for free-form concrete materials in a short period of time. This project develops a production technology of quality free-form concrete panels using a CNC machine and verifies the shape quality through an experiment. We designed a multi-point press CNC machine and verified its quality. The CNC machine implements a smooth free-form shape by changing the shape of the silicon plate by movement of the rods. The silicone plate for the CNC machine generates a slight error due to the elastic cover and mechanical clearance. The mean error rate was within 3%, based on the thickness of the panels, at the 95% confidence level. Verification of these errors will provide meaningful information to a similar type of machine development. In addition, the project results will be helpful in technological development for the production of free-form concrete panels of uniform quality, whose shape accuracy is not influenced by the skills and competence of the workers producing the panels.

A nanoscale vacuum field emission gated diode with an umbrella cathode

A nanoscale field emission vacuum channel gated diode with an umbrella-like cathode is fabricated. The bottom silicon plate is the gate with the anode located between the cathode and the gate, which reduces leakage current.

Вариация состояния поверхности в ходе сканирования в низковольтном РЭМ и ее влияние на размеры рельефной структуры

The emission variation of SSE from surface fragments of protrusions in a silicon plate is evaluated during prolonged scanning in low energy SEM. Emission dynamic variation that is especially complex near the edges of protrusion upper bases and slopes is discovered that affects the sizes of all protrusion fragments. Emission variation is explained with changes of unevenly localized charge state at different surface fragments of protrusions in a natural silica and a contamination film. Contamination is occurred in vacuum and depends on a surface charge state so it is not uniform along protrusion surface. The total absence of contamination on some protrusions is fixed so its initial linewidth size is occurred a constant during a scanning. The limiting uprising of a linewidth size to 4.5 at a one case and the limiting decrease to -0.8 at another case are fixed. Yu. V. Larionov, Senior Researcher, A.M. Prokhorov General Physics Institute, RAS, Moscow, 119991, Russian Federation, E-mail: [email protected], Yu. V. Ozerin, Leading Engineer, [email protected] Mikron Co., Zelenograd, Russia

Особенности механизма диффузии в структуре алюминий-кремний при облучении ее поверхности внеэлектродной плазмой высоковольтного газового разряда

Features of the diffusion mechanism in Al-Si structure when its surface is irradiated by off-electrode plasma of high-voltage gas discharge at discharge current I=50 mA, accelerating voltage U=4 kV and radiation durations 90 s < t ≤ 600 s are investigated. Model for calculating the concentration profiles of aluminum impurity distribution in silicon plate as a function of Al-Si structure irradiation parameters is proposed; corresponding analytical dependences and also good consent of the theory and experiment are obtained. It is shown that the maximum values of diffusant concentration are reached at a penetration depth of electrons into the semiconductor because of forming of vacancies by them in a layer (х ≈ 0.25 μm). Specified is followed by increase at 2-3 orders of coefficient of thermal diffusion.

Silicone Plate for the Prevention of Postoperative Adhesions in Patients with Asherman Syndrome

Purpose. Re-adhesion rates following hysteroscopic adhesiolysis have remained high. Accordingly, we present a case involving temporary placement of an intrauterine silicone plate to prevent re-adhesions following hysteroscopic adhesiolysis in a 36-year-old woman with Asherman syndrome. Methods. After hysteroscopic adhesiolysis, a silicone plate molded to the uterine cavity’s shape was inserted into the uterine cavity and left in place for 1 month. Results. The patient had a history of endometrial curettage for endometrial polyps. After the procedure, she developed amenorrhea and experienced infertility for 5 years despite four cycles of in vitro fertilization and embryo transfer. Following admission to our hospital, hysteroscopic examination showed a wide area of intrauterine adhesions for which hysteroscopic adhesiolysis and silicone plate insertion were performed. The silicone plate was removed after 1 month. No intrauterine adhesions were observed during the subsequent hysteroscopic examination. After a thawed embryo transfer, the patient became pregnant and delivered a healthy baby. Conclusions. A silicon plate may be considered a useful tool for preventing re-adhesion following hysteroscopic adhesiolysis without serious complications.

FRICTION AND ADHESION OF MONOMOLECULAR COATINGS

The paper presents data on measurements of friction and adhesion forces of silicon ball and silicon plate covered by DDPO4 (dodecylphosphoric acid ester), ODPO4 (octadecylphosphoric acid ester), SEBS (poly[styrene-b-(ethylene-co-butylene)-b-styrene]) and OTS (octadecyltrichlorsilane) and others. Tests were performed with reciprocating microtribometer and contact adhesion meter. The experimental results have shown, that coefficient of friction, between a silicon ball and silicon substrates modified by the monomolecular films, are varied in the range 0.05…0.25, with wear-resistance from 20 to 2000 cycles. An ambiguous correlation was found between friction and contact adhesion forces of investigated surfaces.