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Eight undescribed isosteroidal alkaloids cirrhosinones A-H (1-8), along with six known isosteroidal alkaloids (9-14), were isolated from the bulbs of Fritillaria cirrhosa D. Don. Their structures were determined by HRESIMS and 2D NMR analysis, and their absolute configurations were established by X-ray analysis. Compounds 1-8 possessed a typical cevanine-type alkaloid skeleton with a hydroxyl group rarely substituted at C-24 and compounds 4-8 possessed rare 7α or 7β-hydroxyl groups. This was the first report of both C-7 and C-24 hydroxyl groups substituted cevanine-type alkaloids. In addition, an approach for distinguishing D/E cis and trans conformations of cevanine-type alkaloids by

The ceramic wastes can cause strong damage to the environment. In this article, the experimental study was concentrated on the pozzolanic activity of household ceramic waste and clay bricks waste. The possibility of the partial replacement of Portland cement blended with ceramic waste powder without further heating treatment in different ratios was analyzed. The ceramic waste powder was mixed in samples in various ratios. The evaluation of the ceramic waste powder was performed by grain-size analyses using Laser granulometry, XRD, XRF, Frattini test and strength activity index (SAI) method. The results indicate that the pozzolanic activity of household ceramic waste was higher than that of clay bricks waste. The 15% of HC powder addition could be a possible upper bound for an effective substitution and may also be very cost-efficient for industrial application., The authors acknowledge the National Natural Science Foundation of China: Grant 51578109, and Fundação para a Ciência e a Tecnologia (SFRH/BPD/22680/2005).

The SiC brazing mirror is the mirror whose blank is made by assembling together smaller SiC pieces with brazing technique. Using such kinds of joining techniques, people can manufacture large and complex SiC assemblies. The key technologies of fabricating and testing SiC brazing flat mirror especially for large aperture were studied. The SiC brazing flat mirror was ground by smart ultrasonic-milling machine, and then it was lapped by the lapping smart robot and measured by Coordinate Measuring Machine (CMM). After the PV of the surface below 4um, we did classic coarse polishing to the surface and studied the shape of the polishing tool which directly effects removal amount distribution. Finally, it was figured by the polishing smart robot and measured by Fizeau interferometer. We also studied the influence of machining path and removal functions of smart robots on the manufacturing results and discussed the use of abrasive in this process. At last, an example for fabricating and measuring a similar SiC brazing flat mirror with the aperture of 600 mm made by Shanghai Institute of Ceramics was given. The mirror blank consists of 6 SiC sectors and the surface was finally processed to a result of the Peak-to-Valley (PV) 150nm and Root Mean Square (RMS) 12nm.

Both the Ceramic wastes and the pollution of the cement industry can cause strong damage to the environment and the sustainable development. In the present study, the pozzolanic activity of household ceramic waste powder was investigated by SAI test and Frattini Test; the possibility of the partial substitution of Portland cement blended with ceramic waste powder was analyzed. The results indicate that the compressive strengths of mortar containing ceramic waste at both early age and after 28 days were generally increased as the ceramic waste ratio increased up to at least 15\% replacement, and the ground ceramic waste show clear pozzolanic activity., The authors acknowledge the National Natural Science Foundation of China (Grant: 51578109), and Fundação para a Ciência e a Tecnologia (SFRH/BPD/22680/ 2005)., info:eu-repo/semantics/publishedVersion

A zerodur mirror whose aperture is 900mm is chosen to be the primary mirror of an optical system. The mirror is polished by rapid polishing and precision polishing methods relatively. The final surface figures of the mirror are as follows: the peak-to-valley value (P-V value) is 0.204λ (λ=632.8nm), and the root-mean-square value (RMS value) is 0.016λ, which meet the requirement of the optical system. The results show that the polishing process is feasible.

There are numerous reflecting optical system designs that call for large-aperture convex surfaces, such as secondary mirror in on-axis three mirror anastigmatic (TMA). Several methods to test high accuracy hyperboloid convex surfaces are introduced separately in this paper. A kind of arrangement is chosen to test a surface with diameter of 420mm, radius of 1371mm, and conic K -2.1229. The CGH compensator for testing is designed, which is made up of illumination lens and hologram test plate with designed residual wavefront aberration less than 0.001λ (RMS). The second transmitted method that is equipped with a technical flat surface coating by Ag film in the bottom of surface mirror under test, which form an auto-collimation optical system to eliminate the aberration. The Hindle-Simpson test that requires a larger meniscus lens to compensate the optical aberration, and the designed result of optical test system is less than 0.0016λ. Contrasting the CGH compensator and the second transmitted method, the Hindle-Simpson testing method has the advantage of it is easily to manufacture and adjust; meanwhile the test result is stable and has been less affected by the environment. It has been found that the method is rational and reliable, and it can fulfill the requirement of manufacturing and testing process for hyperboloid convex mirrors.