The reactions of tri-2-benzofuranylborane or aminoethyl di-2-thienylborinate and 2-thienylphenylborinate with dichlorocarbene generated in situ from chloroform under phase transfer conditions were explored as a new ro...The reactions of tri-2-benzofuranylborane or aminoethyl di-2-thienylborinate and 2-thienylphenylborinate with dichlorocarbene generated in situ from chloroform under phase transfer conditions were explored as a new route for the preparation of heteroaromatic ketones. It was found that a good yield of the ketones can be obtained by solid-liquid system.展开更多
Implant insertion is an alternative to classical treatment with bridges after tooth extraction or traumatic tooth loss in the anterior and premolar region of the upper and lower jaw. Nevertheless both types of prosthe...Implant insertion is an alternative to classical treatment with bridges after tooth extraction or traumatic tooth loss in the anterior and premolar region of the upper and lower jaw. Nevertheless both types of prosthetic treatment inhere major gingival aesthetic pitfalls by physiological vertical and horizontal resorption. Aim of the study was to investigate if the immediate insertion of root analogue single-stage implants and prosthetic treatment could prevent gingival recessions and bone resorption thus keeping the natural gingival aesthetics untouched. Between 2003 and 2006, 348 root analogue Q1-Implants (TRINON Karlsruhe GmbH/Germany) were inserted in 342 patients’s premolar and molar regions immediately after tooth extraction or traumatic tooth loss and treated with provisional resin crowns. The observation period with recurring 6-month clinical and radiographic check-ups was a minimum of 5 years. Of 348 inserted implants 4 (1.15%) were lost resulting in an overall success rate of 98.85%. In the first 12 weeks after surgery a mean recession of the buccal gingival margin of 0.2 mm (SD 0.34) could be detected, after final prosthetic treatment an overall mean recession of 0.2 mm (SD 0.13) within the survey period. Immediate implant insertion of root analogue single stage implants and immediate prosthetic treatment with provisional resin crowns after minimal invasive tooth extraction seems to be appropriate to prevent bone resorptions of the buccal alveolar crest and the recessions of the gingiva and papillae and thus suggests to be the preferable treatment to keep the natural gingival and papillary aesthetics untouched preventing further traumatic surgical gingival reconstructions.展开更多
This paper describes the statistical study of important factors that influences transient over voltages resulting from three-phase reclosing of shunt compensated transmission lines. These factors include the model use...This paper describes the statistical study of important factors that influences transient over voltages resulting from three-phase reclosing of shunt compensated transmission lines. These factors include the model used for transmission line representation and the influence of line transposition. Additionally, the over voltages reduction to proper levels depending on the type of control technique are illustrated and analyzed in statistical terms. The evaluation covers three shunt compensation degrees. The digital simulations were performed using the PSCAD/EMTDC software.展开更多
文摘The reactions of tri-2-benzofuranylborane or aminoethyl di-2-thienylborinate and 2-thienylphenylborinate with dichlorocarbene generated in situ from chloroform under phase transfer conditions were explored as a new route for the preparation of heteroaromatic ketones. It was found that a good yield of the ketones can be obtained by solid-liquid system.
文摘Implant insertion is an alternative to classical treatment with bridges after tooth extraction or traumatic tooth loss in the anterior and premolar region of the upper and lower jaw. Nevertheless both types of prosthetic treatment inhere major gingival aesthetic pitfalls by physiological vertical and horizontal resorption. Aim of the study was to investigate if the immediate insertion of root analogue single-stage implants and prosthetic treatment could prevent gingival recessions and bone resorption thus keeping the natural gingival aesthetics untouched. Between 2003 and 2006, 348 root analogue Q1-Implants (TRINON Karlsruhe GmbH/Germany) were inserted in 342 patients’s premolar and molar regions immediately after tooth extraction or traumatic tooth loss and treated with provisional resin crowns. The observation period with recurring 6-month clinical and radiographic check-ups was a minimum of 5 years. Of 348 inserted implants 4 (1.15%) were lost resulting in an overall success rate of 98.85%. In the first 12 weeks after surgery a mean recession of the buccal gingival margin of 0.2 mm (SD 0.34) could be detected, after final prosthetic treatment an overall mean recession of 0.2 mm (SD 0.13) within the survey period. Immediate implant insertion of root analogue single stage implants and immediate prosthetic treatment with provisional resin crowns after minimal invasive tooth extraction seems to be appropriate to prevent bone resorptions of the buccal alveolar crest and the recessions of the gingiva and papillae and thus suggests to be the preferable treatment to keep the natural gingival and papillary aesthetics untouched preventing further traumatic surgical gingival reconstructions.
文摘This paper describes the statistical study of important factors that influences transient over voltages resulting from three-phase reclosing of shunt compensated transmission lines. These factors include the model used for transmission line representation and the influence of line transposition. Additionally, the over voltages reduction to proper levels depending on the type of control technique are illustrated and analyzed in statistical terms. The evaluation covers three shunt compensation degrees. The digital simulations were performed using the PSCAD/EMTDC software.