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In this paper, a novel type of isolator, named segmented intelligent isolation bearing (SIIB), is designed and manufactured, which can meet the requirements of seismic fortification under three seismic intensities, i.e. frequent intensity, basic intensity, and rare intensity. A theoretical formula for the output of the SIIB is established to provide a basis for the determination of the size of the SIIB. MRE and STMP used in SIIB were prepared, of which the changes of shear storage modulus and damping factor with the magnetic field under different strain are analyzed. The mechanical properties of the SIIB under small displacement, medium displacement, and large displacement are tested, respectively, and the hysteretic characteristics of force–displacement are analyzed. The dynamic mechanical model combining the rheological model, phenomenological model, and bilinear restoring force model is established to represent the behavior of the SIIB. The results showed that the theoretical results agree well with the experimental results, and the model can significantly reflect the dynamic characteristics of SIIB.

In order to control the vibration of civil building structures, a smart extrusion-type isolator was developed based on magnetorheological gel (MRG) and magnetorheological elastomer (MRE). The key technology and performance tests of the isolator were investigated as well as the identification of parameters of the mechanical model. Test results showed that the MRG cylinder has a damping characteristic at high frequency while the MRE cylinder has an isolation characteristic at low frequency. The designed isolator is therefore superior over the traditional isolator since it will show small damping and low dynamic stiffness at a high frequency and small amplitude situation, which can overcome stiffness hardening that occurs on the traditional isolator. Meanwhile, the designed isolator will also have the behavior of large isolation and high dynamic stiffness under the low frequency and large amplitude condition, which has the advantage of realizable displacement control. The uniaxial mechanical model for the MRG/MRE smart isolator was built, and the parameters of the designed vibration isolator were identified. Theoretical results obtained from the mechanical model of the MRG/MRE smart isolator agree well with the experimental results indicating that the parameter identification method is feasible and effective.

In order to control the vibration of civil building structures, a magnetic rate-controlled stage damper (MRCSD) is designed based on a magnetorheological shear thickening fluid (MR-STF). The key technology and performance test of the damper and the parameter identification of the mechanical model are studied. The experimental results show that the main cylinder filled with MR-STF combines the magnetorheological (MR) effect and the shear thickening effect, which has a strong impact on energy dissipation and vibration reduction. Therefore, the designed damper is superior to the traditional viscous damper. With the increase of magnetic field strength, the shear thickening effect of the MR fluid is inhibited and the MR effect is more obvious. The MRCSD can improve the performance of vibration isolation and vibration reduction by controlling damping. Under a different intensity of earthquake, the maximum output can reach 250.2 kN; the mechanical model of the MRCSD is established; and the design parameters of the damper are determined. The theoretical results obtained from the mechanical model of the MRCSD are consistent with the experimental results, which show that the parameter identification method is feasible and effective.

To study the effect of cytochrome P-4504F2 (We collected 350 patients receiving warfarin after mechanical heart valve replacement from January 2013 to December 2015 in our hospital. According to the international standardized ratio (INR) ≥2 at the initial stage after surgery, the patients were divided into two groups: INR≥2 group and INR2 group. We selected the blood samples of all the 350 patients with testing theThere was no statistical significance in the initial dose of warfarin among patients with different

A series of magnetorheological composite gels (MRCG) were prepared using carbonyl iron powder as the magnetic particles, a complex of methyl silicone oil and gelatin/agaropectin colloids as the matrix and various additives. The rheological behaviour of the samples was tested using a rheometer in rotary and oscillatory shear modes. The results demonstrate that rheological behaviour is significantly dependent on the colloid content of the matrix. The shear yield strength increases with increasing colloid content of the matrix and reaches a maximum of 92.1 kPa. The linear viscoelastic range of the MRCG is almost independent of colloid content. In addition, the shear storage modulus of the MRCG increases with increasing colloid content, and the maximum value of the change in absolute modulus is 2.526 MPa. Adding nanosized SiO2 can significantly improve the shear yield stress and broaden the controllable range of the MRCG under a magnetic field.

A type of Magneto-Rheological Materials (MRMs) was prepared. The off-state viscosity and the shear stress of the MRMs were characterized and studied by an advanced rotational rheometer system. A kind of Self-Decoupling Magneto-rheological (SDMR) damper was established based on these MRMs. An intellectual isolation system for grid structures was obtained by integrating SDMR damper and isolation device. The seismic whiplash effect of the top bent frame column and space grid roof of the hydropower plant could be reduced. Furthermore, the half stable increment method was proposed as the semi-active strategy. The results indicated that the SDMR dampers used at the grid roof supports setting plate rubber bearings can significantly improve the vibration performance and energy dissipation structure roof isolation system in different seismic intensity. In addition, these SDMR dampers can effectively reduce the lateral slippage of the plate rubber, so as to avoid failure or damage of the isolation system because of the transfinite horizontal displacements. Compared with the conventional damper only in case of multiple earthquakes, the damping force and adjustable multiple of this SDMR damper have better adaptability, and this SDMR damper provides a higher safety factor.

Bridge pier collision avoidance system is a hot research topic. As the representative of the intelligent material, the Magnetorheological Grease has become one of the main research directions in the research of bridge pier collision due to its special mechanical properties and rheological properties. In this work, we present a bridge pier collision avoidance system using Magnetorheological Grease Material. Firstly, according to the characteristics of bridge pier collision, a series of Magnetorheological Grease Material are configured, and then the collision avoidance structure of the actual size of the bridge pier is given. The structure can be directly applied to the bridge pier collision avoidance. Secondly the experimental characteristics of the Magnetorheological Grease Material are given, and the experimental results are analyzed. The strong theoretical guidance and engineering basis were provided for the related scientific and technical workers and researchers.

In this paper, on the basis of the viscoelastic fractional derivative model, Mittag-Leffler function is applied to deduce the expression of stress relaxation modulus for magnetorheological elastomers according to its form and main properties. Furthermore, the relaxation modulus for polyurethane rubber matrix cured magnetorheological elastomers at different applied magnetic fields and shear strains is tested by rheometer. The results indicate that magnetorheological elastomers exhibit obvious relaxation behavior and the magnetic field strength and shear strain exert significant influence on the relaxation behavior: the relaxation modulus of magnetorheological elastomers increases with the magnetic field strength but decreases with the shear strain. Besides, the model agrees well with the experimental data which indicates that the model is suitable for characterization of relaxation behavior for magnetorheological elastomers.

The modified carbonyl iron powders with single particle size (single-grading) and binary particle sizes (double-grading) were added in the composite gel, which was prepared by using methyl silicone oil, gelatin and agaropectin colloids as raw materials, and then the single-and double-grading magnetorheological composite gels (MRCGs) were prepared by vacuum decompression. The effects of particle size and gradation of carbonyl iron power on the rheological behavior of the MRCGs were studied. The results show that the shear strength of single-grading MRCGs decreased gradually with the decrease of the carbonyl iron particle size. However that the shear strength of the double-grading MRCGs with the gradation of 90 wt% un-ball-milled and 10 wt% ball-milled carbonyl iron powders first increased then decreased with the elongation of milling time (the decrease of carbonyl iron paticle size) and reached 99.6kPa when ball milling time for 24h, which was 17.8kPa larger than that of un-ball-milled single-grading MRCGs.

In this paper, we establish the mechanical property analysis of Single-walled Carbon Nanotubes (SWCNTs) modified beam element model based on the molecular structural mechanics method. Then we study the mechanical properties of their radial direction characteristics using the finite element software Abaqus. The model simulated the different bending stiffness with rectangular section beam elements C-C chemical force field. When the graphene curled into arbitrary chirality of SWCNTs spatial structure, the adjacent beam position will change the moment of inertia of the section of the beam. Compared with the original beam element model and the calculation results, we found that the established model largely reduced the overestimate of the original model of mechanical properties on the radial direction of the SWCNTs. At the same time, compared with other methods available in the literature results and the experimental data, the results can be in good agreement.

A novel shear thickening magnetorheological (STMR) damper with both speed locking and semiactive controlling properties was designed and fabricated based on multifunctional smart composite materials which was defined as magnetorheological Silly Putty (MRSP). The rate sensitive property and magnetorheological effect of MRSP samples were analyzed by using a rheometer to select the best filler for the STMR damper. The mechanical properties of the STMR damper were investigated through slow, fast, and dynamic experiments. The experimental results indicate that the STMR damper exhibits an obvious rate sensitive characteristic and semiactive control property. On one hand, when the STMR damper is simulated fast enough, it can realize the “speed switch” function, which enables it to instantly lock up and act as a shock transmission unit (STU). On the other hand, when the STMR damper is applied with current, the damping force can be adjusted by magnetic field strength to realize its semiactive controlling property. In addition, a multiparameter and symmetry model was established to describe the dynamic hysteretic behavior of the STMR damper, which is consistent with the experimental data.

In this paper, the influence of the soft magnetic particle content on the properties of MRFs is studied. Besides, the relationships between the shear stress of MRFs and the magnetic induction intensity, the soft magnetic particle content, and the shear rate are discussed. The curve equation that expresses the relationship between the shear stress, the magnetic induction intensity, and the soft magnetic particle content is established through the fitting of experimental data. The results show that the shear stress of MRFs increases with increasing magnetic induction intensity and that the shear stress will tend to stabilise when the magnetic induction intensity reaches a sufficient value. The validity of the Bingham model and the H-B model for describing the relationship between the shear stress and shear rate is established, and the phenomenon of shear thinning of MRFs can be better represented by the H-B model than by the Bingham model.

The first metal–organic coordination polymer of amino-acid functionalized naphthalenediimide (NDI) ligand, [Zn(Gly-NDI)(DMF)2]n (1), has been synthesized and characterized. Single-crystal X-ray diffraction revealed that the Zn ions are linked by anti-conformational Gly-NDI ligands, and 1 displays a one-dimensional zigzag chain coordination polymer. These chains are cross-linked through strong π···π stacking interactions between NDI cores to give a three-dimensional supramolecular framework with square planar 4-connected CdSO4 (cds) topology. The thermal stability and fluorescence emissions of 1 were also investigated.

A novel magnetorheological material defined as magnetorheological Silly Putty (MRSP) is prepared by dispersing soft magnetic particles into Silly Putty matrix with shear stiffening property. Static mechanical properties including creep and stress relaxation and dynamic rheological properties of MRSPs are tested by rheometer. The experimental results indicate that the external magnetic field exerts significant influence on the creep and relaxation behaviors. Moreover, the storage modulus of MRSPs increases sharply in response to the external stimuli of increasing angular frequency automatically and can be enhanced by external magnetic field. Besides, temperature plays a key role in shear stiffening and magnetorheological effect of MRSPs. Furthermore, considering the obstruction to the particle chains formation induced by Silly Putty matrix, a nonperforative particle aggregated chains model is proposed. The model curve is in consistency with experimental data, which means it can describe magnetoinduced behavior of MRSPs well.

A flux with MnCl2 is used to control the morphology of microstructure in Al-1Fe alloys. An orthogonal test plan (L(33)) was employed to study the effect of the ratio of Mn/Fe, temperature and holding time on the morphology of the Fe-rich phase. Metallographic and image analys is techniques have been used to quantitatively examine the microstructural changes occurring with Mn addition. XRD analysis is employed to identify the phase of intermetallic compound in the alloy. It is found that when the ratio of Mn/Fe in the melt is located in the range from 1.5 to 2.0, the original needle like iorn phase can be transformed to be massive morphology, such as Chinese script, globule or polyhedral, and the area fraction of iron phase in the Al-1Fe alloy can be reduced by adding MnCl2 during the melt processing.

The influence of carbonyl iron particles sizes on the properties of magneto-rheological fluids (MRFs) were studied. Different-sized carbonyl iron magnetic particles were prepared by ball milling with different milling times. On this basis, different particle MRF were prepared The off-state viscosity and the shear stress of the above MRFs were characterised and studied by an advanced rotational rheometer system. The test results show that the off-state viscosity and the shear stress of single-particle MRFs were enhanced with increasing average carbonyl iron particle size at a constant magnetic field. The shear stresses of MRFs containing two or three different particle sizes were significantly improved compared with the MRFs containing only a single particle size. At a reasonable level of medium and small size carbonyl iron particle spread throughout the structure of the multiple-particle MRFs, the defects in the chain structure were remedied when a chain reaction occurred, and the mechanical properties of MRFs were enhanced. Meanwhile, increased mass fractions of the small size carbonyl iron particle resulted in a reduction in overall average particle size of MRFs, and the mechanical properties of MRFs were also reduced. The mechanical properties of multiple-particle MRFs were observed to be strongly dependent on the size and mass fraction of the medium and small carbonyl iron particles.

Numerical simulation and experimental analysis for a magnetic circuit model of a damper were carried out by adjusting the size of the auxiliary gap to obtain greater magnetic field strength and wider adjustable multiples of the damping force. Results of experiment indicate that there is a specific ratio of sizes between the auxiliary gap and the working gap; this gap ratio is 3:1. The adjustable multiple and gap ratio is validated by the results of the experiment. The largest value for the magnetic induction in the working gap can reach 80–90% of the maximum; the least value is close to zero, and the adjustable multiple of the magnetic induction is near about a factor of 7. Experimental data also indicate that the law of the magnetic flux leakage is affected by the size of auxiliary gap as well as the intensity and direction of the current. Performance testing of the real optimal damper reveals that the maximum damping force of the damper is 195.7 kN, which is ~92.7 percent of the theoretical maximum value, at a gap ratio of 1:2.5.

The Cu-Ni-Si-Mg alloy was treated by aging after varying cold deformation. The effect of cold deformation, aging temperature and aging time on the microstructure and properties of the alloy were investigated. The results indicate that the alloy produce a larger number of slip bands and dislocations after cold deformation, it can accelerate the precipitation of phase during aging, improve the microhardness and electrical conductivity. The microhardness and electrical conductivity of the alloy with 80% deformation aging at 723 K for 1h are 242HV and 35.53%IACS, respectively. The volume fraction of the precipitated phase was calculated by measuring the electrical conductivity of the alloy with 80% deformation aging at 773 K, then both the equations of phase transformation and the electrical conductivity equation were obtained.

Nanometer calcium carbonate (nano-CaCO3) is an inorganic material that does not have the rheological properties of a magneto-rheological fluid (MRF) but has some effects on the sedimentary stability and rheological properties of MRF. The MRF was prepared by adding nano-CaCO3 to improve its comprehensive and practical properties. The results showed that, with an increase in the amount of nano-CaCO3, the sedimentary stability of MRF would be improved. The off-state viscosity of MRFs increased with an increasing amount of nano-CaCO3. The shear stress of MRF was decreased slightly by adding nano-CaCO3. To some extent, the comprehensive and practical properties can be improved by adding a certain amount of nano-CaCO3. However, there is also certain localization that properties of MRF are improved by adding Nano-Inorganic Materials in the high temperature environment.

Studies on the dynamic properties of long-span floor is an essential basis for a solution to the problem of human-induced vibration serviceability. According to the recent research, this review introduces the application of numerical simulation in the research of dynamic properties and summarizes the modeling method of sophisticated finite element model. The reliability of the finite element model is verified by the field test and model test. Comparing the application of studies on dynamic properties among numerical simulation and model test, the differences between numerical simulation and model test are summarized. Finally, some problems that need further study are proposed.

High yield synthesis of bamboo-like multi-walled carbon nanotubes (BCNTs) over a novel zeolite catalyst has been achieved using acetonitrile as a carbon source. The synergism of nickel (Ni) and rare earth oxides (REO) in the zeolites is considered very important for the high activity of the catalysts for the rapid decomposition of acetonitrile and diffusion of carbon. The yield of BCNTs increases with the Ni content and the growth time. The as-grown BCNTs are arranged in the form of flower-like clusters surrounding each zeolite. This CNT-zeolite composite may be regarded as a complex zeolite which will be very useful for the selective absorption, filtration and storage of gas.