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A copper-catalyzed three-component reaction of ynones, aryl iodides, and elemental sulfur via a syn-addition process is established. The reaction features operational practicality, broad substrate scope, and readily accessible scale-up synthesis by affording a series of (Z)-1,2-bis(arylthio)alkenes in good to excellent yield. Moreover, benzo[b][1,4]dithiines can be also constructed efficiently by using 1,2-diiodobenzene as the coupling partner.

During the past decade, self-assembly of saccharide-containing amphiphilic molecules toward bioinspired functional glycomaterials has attracted continuous attention due to their various applications in fundamental and practical areas. However, it still remains a great challenge to prepare hierarchical glycoassemblies with controllable and diversiform structures because of the complexity of saccharide structures and carbohydrate-carbohydrate interactions. Herein, through hierarchical self-assembly of modulated amphiphilic supramolecular metallocarbohydrates, we successfully prepared various well-defined glyco-nanostructures in aqueous solution, including vesicles, solid spheres, and opened vesicles depending on the molecular structures of metallocarbohydrates. More attractively, these glyco-nanostructures can further transform into other morphological structures in aqueous solutions such as worm-like micelles, tubules, and even tupanvirus-like vesicles (TVVs). It is worth mentioning that distinctive anisotropic structures including the opened vesicles (OVs) and TVVs were rarely reported in glycobased nano-objects. This intriguing diversity was mainly controlled by the subtle structural trade-off of the two major components of the amphiphiles, i.e., the saccharides and metallacycles. To further understand this precise structural control, molecular simulations provided deep physical insights on the morphology evolution and balancing of the contributions from saccharides and metallacycles. Moreover, the multivalency of glyco-nanostructures with different shapes and sizes was demonstrated by agglutination with a diversity of sugar-binding protein receptors such as the plant lectins Concanavalin A (ConA). This modular synthesis strategy provides access to systematic tuning of molecular structure and self-assembled architecture, which undoubtedly will broaden our horizons on the controllable fabrication of biomimetic glycomaterials such as biological membranes and supramolecular lectin inhibitors.

Continuous cooling transformation (CCT) diagram of a high strength weathering prefabricated building steel was determined using a DIL805L thermal dilatometer by means of the expansion method combined with metallography hardness method. Effect of cooling rate on microstructure and hardness of the steel was also studied. The results show that the austenite transformation products of the steel are ferrite and pearlite when cooling rate is lower than 3°C/s. In the cooling rate range of 3 to 20°C/s, the mixed microstructure of ferrite, pearlite and bainite can be obtained. When cooling rate is higher than 20°C/s but lower than 100°C/s, the microstructure is composed of ferrite, bainite and martensite. When cooling rate is above 100°C/s, ferrite disappeared completely, and transformation products are bainite and martensite.

The safety of a reinforced concrete frame building with cracks on a large area of its wall was investigated by using numerical analysis and field tests. The cracks were caused by the roof additional equipments. The layout of the roof additional equipments was measured to determine their additional loads. The width and depth of existing cracks was also measured. The static strength analysis based on the finite element technique is used to evaluate the influence of the additional loads on structural strength. The research results show the unreasonable supports of additional loads and the insufficient stiffness of secondary beams are the main reasons for causing cracks on the wall, and a reinforcement and repair thought for the building is proposed.

This passage mainly studies the change of stress and penetration in the process of precast piling. According to the construction of guide bar diesel pile diver and the piling process of diesel pile driver in the reality, this passage analyses the stress and penetration in the process of precast piling practically and theoretically with the LS-DYNA module of the finite element software, ANSYS, before which the piling experiment has been done. And the conclusion will be reference in later engineering site.

The slewing bearing of the full-revolving super large lifting equipment bears all loads above the rotating platform. Due to the effect of bending moment, the load conditions of the slewing bearing structure is complex and large, which leads to the non-uniform of stress and uneven deformation and final seriously affects the work performance of lifting equipment. The numerical example in this paper considers three kinds of sliding-friction models between slewing bearing structure and orbit. By numerical analysis results, we adjusted the structure arrangement and stiffness distribution. Finally the non-uniform of stress of the slewing bearing structure has been improved and tended to be uniform. Thus the paper presents a new approach for the design of the slewing bearing in super large lifting equipment.

OGFC can reduce traffic noise which has very high air-void contents to absorb tire-pavement noise. This paper proposes maximum aggregate size and aggregate gradation of OGFC with the objective void of 20%. Performance of modified asphalt and best asphalt-aggregate ratio are also proposed with four kinds of modifiers, including SBS, rubber, EVA and PVC. The absorption coefficients of the four kinds of OGFC and the dense-graded Marshall specimens were tested with standing wave tube. Then their sound absorption performances were compared.

This paper gives a report on the geophysical, geological and geochemical studies of the Panxi rift. The results of wide-scale gravity measurements, deep seismic soundings, aeromagnetic, geomagnetic, geothermal and seismicity investigations, which have been carried out by the Institute of Geophysics of the Academia Sinica, are presented and analysed. Thereby the results from Geotraverse I are discussed in detail. The following rift-associated features have been found: an intracrustal low velocity and resistivity layer, lower than normal velocities of 7.6–7.9 km/s and low resistivity of 250 Ωm in the upper mantle, elevated velocities and resistivities in the central region; doming as analysed from the gravity and seismicity data, N-S rift oriented positive magnetic anomalies in the central region, N-S striking faults and N-S oriented distribution of basic and ultrabasic Proterozoic rocks and grabens. It is shown that the region containing the Panxi rift was subjected to extensional and compressional tectonics which started in the late Proterozoic and found their climax in the late Palaeozoic. The recent compressional tectonics are considered to relate to the collision of the Indian and Eurasian plates. Rifting and igneous processes during the tectonic evolution of the Panxi rift are compared with the major continental rifts and conceptual models for the various rifting episodes are presented.