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A photocatalyst-free and EDA complex-enabled radical cascade cyclization reaction of inactive alkenes with bromodifluoroacetamides was reported for the divergent synthesis of fluorine-containing tetralones and quinazolinones. In this transformation, persulfates as electron donors and difluoro bromamide as electron acceptors generate the EDA complex. This is a promising photochemical method with advantages such as mild reaction conditions, simple operation, being metal-free, and excellent functional group tolerance.

The effects of steel slag with 0, 10%, 20 % and 40% content on the chemical shrinkage, autogenous shrinkage, internal relative humidity, and drying shrinkage of calcium sulfoaluminate cement paste were studied. The results show that the compressive strength of calcium sulfoaluminate cement paste at an early stage decreases gradually when the content of steel slag increases. When the steel slag content is 0 and 10%, the compressive strength of hardened cement pastes gradually decreases at 90 and 180 days, but the samples with steel slag content of 20% and 40% maintain the compressive strength growth within 180 d. With the extension of curing period, the gap of compressive strength is gradually narrowed. The autogenous shrinkage decreases with the increase of steel slag content and has a good linear relationship with the relative humidity inside the paste. The proportion of autogenous shrinkage to chemical shrinkage is deficient, and most chemical shrinkage occurs in the form of the pore volume. Although the trends of drying shrinkage and autogenous are consistent, the former is more severe than the latter.

For a wind energy generator, the most significant factor which decreases the working life of it is the vibration from the rotating turbine blades under wind. In this paper, we do modeling and simulating in the constrained layer damping (CLD) approach, which is called passive control. Here, we use software PRO/ENGINEER to design and model a wind turbine blade before using COMSOL to simulate the dynamic motion of the wind turbine blade and its interaction with aerodynamic force of wind in finite element method. Some different models are built, the original turbine blade and the turbine blade with damping patches on different location and quantity. Then, according to the simulation results, we compare the effects of passive damping control in defferent patches locations and quantities under different wind speed. This research can provide us foundation and comparision with our future study which is related to the piezoelectric layer damping (PLD).

On the basic of passive damping control, we do modeling and simulating in another approach to improve the vibration alleviating effect, the piezoelectric layer damping (PLD), which is called active control. The piezoelectric damping patches are under control of PID controller (matlab simulating) in voltage defference. Here, we use the software PRO/ENGINEER to design and model a wind turbine blade before using COMSOL to simulate the dynamic motion of the wind turbine blade and its interaction with aerodynamic force of wind in finite element method. Some different models are built-- the original turbine blade and the turbine blade with damping patches on different location and quantity. Then, according to the simulation results, we compare the effects of passive and active damping control, also the effect of patches locations and quantities under different wind speed. This research can provide a direction for future study about ways to decrease vibration of turbine blades.

The electrolytic stripping technique (also known as coulometric dissolution) was a method to analysis the phase structure of galvannealed coating quantitatively, but the experimental data of electrolytic stripping cannot be used for straightforward Fe-Zn phase identification, and because quantification needs to take into account the effect of various electrochemical side-reactions. The applicability of electrolytic stripping for the phase analysis of galvannealed coatings was optimized in this article, Result show that electrolytic stripping technique can be applied to realize step-by-step dissolution of various phases species in the galvannealed coatings under the condition that the potential scanning rate was low enough, and the method allows the determination of the total Fe concentration, and the thickness and structure of the η, ζ, δ and Γ phases. Both the thickness and the various intermetallic phases content of the galvannealed coatings with different aluminum contents was characterized by the polarization curve of the electrolytic stripping technique and the proposed data analysis method, and combine the initial dissolution potential of every Fe-Zn phase in galvannealed coating.

The dissolution process of galvannealed (GA) and galvanized (GI) coating was examined by correlating a chemical stripping test in 1MNaCl+0.01MH2SO4 solution. The key time of dissolution process of coating was found via measuring the variation of free corrosion potential. Through coating metallographic observations at the key point, the dissolution process of coating can be clear. There are four Fe-Zn intermetallic phases in GA coating, namely gamma-1,gamma,delta and zeta phases, from the substrate. The compressed part of GA and GI coatings was the initial of corrosion process. The net crack will be emerging on the delta phase, which width graduallyincreasing until stripping. Pitting corrosion occurred on the GI coating in the solution containing Cl- ion, the area and depth of pit gradually increasing until stripping. The corrosion potential of Fe2Al5Znx inhibition layer is about-0.8VSCE.

To measure and detect the shear stress directly in the field, we developed the device. Designed its structure, working principle, technical parameters and selected its material based on the mechanical characteristics of corn stubble in the field we wanted to get. Applied Solid Works software to construct model for it. In this way, people can know about it intuitively. It is able to detect shear stress of corn stubble in the field directly and accurately. Because shear stress is one of the most important theoretical basis for the design of corn stubbles broken to field machine, maize stubbles harvester machine and corn tillage planter, so design of shear stress detection device for corn stubble in this article is very meaningful and promising.

The 1,1′‐binaphthol‐based dimers with p‐phenylenebis(2‐ethynyl) spacer, (+)‐6and (+)‐2, were synthesized as chiral host compounds. 1H NMR, UV‐vis, and fluorescent titration were used to evaluate the enantiomeric recognition abilities of the chiral host dimers toward the guest amine 7and α‐amino acid ester 8. The chiral BINOL‐based dimers were found to have good enantiomeric recognition ability. The computer simulation of the host–guest complex molecules was carried out to describe the conformational changes of both naphthyl ring in the molecule of chiral host dimer after complexation with the guest molecule. Chirality 13:595–600, 2001. © 2001 Wiley‐Liss, Inc.