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Fe3O4 nanoparticles (NPs) have previously been employed in various fields owing to their unique physical and chemical properties. In this paper, Fe3O4 NPs are prepared by co-precipitation method in a helical microreactor under different reaction conditions which affect the size of Fe3O4 NPs. The product is characterized by FT-IR and XPS. Also, VSM characterization shows that Fe3O4 exhibits typical superparamagnetic behavior and the saturation magnetization of NPs is 53 emu/g.

Conditioned pain modulation (CPM) is impaired in people with chronic pain such as knee osteoarthritis (KOA). The purpose of this randomized, controlled clinical trial was to investigate whether strong electroacupuncture (EA) was more effective on chronic pain by strengthening the CPM function than weak EA or sham EA in patients with KOA. In this multicenter, three-arm parallel, single-blind randomized controlled trial, 301 patients with KOA were randomly assigned. Patients were randomized into three groups based on EA current intensity: strong EA (> 2 mA), weak EA (< 0.5 mA), and sham EA (non-acupoint). Treatments consisted of five sessions per week, for 2 weeks. Primary outcome measures were visual analog scale (VAS), CPM function, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Three hundred one patients with KOA were randomly assigned, among which 271 (90.0%) completed the study (mean age 63.93 years old). One week of EA had a clinically important improvement in VAS and WOMAC but not in CPM function. After 2 weeks treatment, EA improved VAS, CPM, and WOMAC compared with baseline. Compared with sham EA, weak EA (3.8; 95% CI 3.45, 4.15; P< .01) and strong EA (13.54; 95% CI 13.23, 13.85; P< .01) were better in improving CPM function. Compared with weak EA, strong EA was better in enhancing CPM function (9.73; 95% CI 9.44, 10.02; P< .01), as well as in reducing VAS and total WOMAC score. EA should be administered for at least 2 weeks to exert a clinically important effect on improving CPM function of KOA patients. Strong EA is better than weak or sham EA in alleviating pain intensity and inhibiting chronic pain. This study was registered with the Chinese Clinical Trial Registry (ChiCTR-ICR-14005411), registered on 31 October 2014.

A novel geopolymer supported nanobimetallic catalyst for isopropanol dehydrogenation was prepared by modified wet impregnation and reduction method. XRD, SEM, EDX and TEM analysis confirmed formation of amorphous geopolymer from the polymerization of metakaolin and deposition of nanometals over the geopolymer support. The bimetallic catalyst containing 5wt. % Cu and 10wt. % Ni loading over geopolymer shows an excellent performance with 23.18% conversion of isopropanol and 88.24% selectivity to acetone under reaction conditions of 90 °C, 3 hours, and catalyst amount of 0.15g/5.0g of isopropanol. Moreover, the catalyst maintains its catalytic stability without noticeable loss of activity after five cycles.

An ecofriendly heterogeneous polyoxometalate (POM)-gold catalyst Au/BW11/Al2O3was synthesized and used for solvent-free epoxidation of cyclooctene under mild reaction conditions using molecular oxygen as an oxidant and t-butyl hydroperoxide (TBHP) as an initiator. The catalyst was characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), induced coupled plasma optical emission spectrometry (ICP-OES), and Brunauer-Emmett-Teller (BET). The catalyst showed good conversion and high selectivity without use of solvents or environmentally harmful oxidants. Moreover, the catalyst is recyclable up to three cycles with no significant loss in selectivity towards epoxide.

The oxidation of cyclohexane to cyclohexanone, cyclohexanol, and adipic acid, which are important raw materials in nylon industry, is still being challenged in conventional processes. Microreactors and gold catalysts are both widely researched areas at present, so an effort was made to make use of collaborative properties of both. In this study, stainless steel microcapillary coated with a supported nano-gold catalyst was prepared, characterized, and employed for the oxidation of cyclohexane. Under the temperature of 180 °C, residence time of 4 min, reaction pressure of 3 MPa and molar ratio of oxygen to cyclohexane of 0.3:1, the conversion of cyclohexane was 2.09%, with the selectivity of cyclohexanol, 29.37%; cyclohexanone, 39.89%; cyclohexyl hydroperoxide, 2.46%; and adipic acid, 18.87%. Experiments showed that stainless steel microcapillary coated with a supported nano-gold catalyst in cyclohexane oxidation is a feasible process; the reaction time is very short, and the process operation runs safely.

Based on the full analysis of draw-bar box types and functions, and summarizes the occupying larger space question of the box when placed in. Through the studies of the wide application of folding structure in the product, for a particular user, carries on the structure improvement design of rod boxes, not only to retain the existing functions commonly used, while achieving clothing classification, convenient placement, save space; embodies the idea connotation of green design, and highlights the importance of structure design for product innovation design.

Mortarless interlocking blocks have the advantage of convenient construction and low cost, but establishing the geometry interlocking mechanism between horizontal blocks has been overlooked. Optimizing the shape of mortarless interlocking block. The connection of vertical direction in the form of a frustum of a cone, and the connection of horizontal direction in the form of trapezoid shape. This design proposal builds geometry interlocking mechanism between the block and its all adjacent ones. Setting cone and rectangular holes on block body, accordingly, block laying could forming taper vertical channel and rectangular vertical channel. The concrete of interlocking mortarless block has particularity, which is not suitable for “Mix Proportion Design of Ordinary Concrete Regulation” (JGJ55-2010) of China. This paper presents a platter idea to establish the concrete mix proportion design method of mortarless interlocking block, moreover, an example calculation and confirmatory experiment is dispensable.

Waste poly(ethylene terephthalate) fibers were depolymerized into bis(2-hydroxyethyl) terephthalate and synthesized as azo dyestuff. The synthesized dyestuff showed bright yellow color and was utilized to dye nylon filaments and fabrics in the acidic dye bath.

A bifunctional comonomer containing both ester and amide groups was synthesized to prepare poly(acrylonitrile-co-3-aminocarbonyl-3-butenoic acid methyl ester) [P(AN-co-ABM)] copolymers used as the carbon fiber precursor instead of poly(acrylonitrile-acrylamide-methyl acrylate) terpolymer. The results show that the stabilization and spinnability of P(AN-co-ABM) copolymers have been significantly improved by the comonomer ABM.

We synthesized water soluble CdTe QDs modified with aspartic acid (ASP). The ASP molecules on the surface of CdTe QDs can facilitate their penetration into the PIEC cells and the biocompatibility examination indicated that ASP modified CdTe QDs did not reduce cell viability.

The heated-mandrel winding method (HMWM) is a new technology. However, the trial-and-error method usually used is not universally adopted in the manufacturing process of shells that have different shapes and performance requirements. Determining the heating process for the HMWM based on theoretical analysis has become an immediate problem. In this paper, a numerical simulation program for the HMWM is developed using the finite element software ANSYS and the programming language APDL. The entire process, which starts with the winding process and ends with the complete curing, is numerically simulated. The temperature distribution and change law, curing degree, and reactive calorific intensity are analyzed. The relationship between the heating process and the outer surface temperature changes of the composite shell is derived based on the principle of temperature control in the HMWM. The heating process is optimized in accordance with the analysis, and the experimental results show that, based on the optimized heating process, the outer surface temperature range of the shell can be controlled during the winding process. Furthermore, the complex interactions among the temperature, curing degree, film coefficient, and heat transfer coefficient of the composite are investigated. This provides the basis for the technology optimization based on theoretical considerations.

The buckle propagation phenomenon in offshore pipelines is an important subject of ocean engineering. The local buckling will easily propagate along the pipeline if the external hydrostatic pressure is high enough. The buckle propagation will seriously hinder the transmission of the oil. This paper focuses on the numerical calculation of buckle propagation pressure using ABAQUS software.

Conductive microfibers with the average diameter around 1.0μm were prepared fabricated through in situpolymerization of aniline using ammonium persulfate as the oxidant, in which poly(vinylchloride-acrylonitrile) (PVC-AN) was used as the filament-materials in electrospinning that to form the precursor microfibers and carry the aniline monomer.

For layout space in the limited land resources and improving the utilization efficiency of urban transportation bridge and traffic conditions, in this paper, according to the request of four lanes of roof, two-way urban light rail traffic in the box, considering the requirements of pipeline layout, water supply and drainage, and fire escape, lighting, ventilated at the same time, based on the existing related specification, give full play to the characteristics of the concrete box girder, preliminarily design out of the single box three rooms inclined web box girder for double-deck traffic of urban bridge, in order to provide the reference design.

Objective: To investigate a better method of inducing hUC-MSCs into chondrocytes in different culture system in vitro. Method: hUC-MSCs were isolated and cultured by tissue block culture, and the cells surface antigens were identified by flow cytometry, hUC-MSCs were cultured with chondrogenic media and stained with Alcian Blue. The production of matrix was estimated from the determination of hydroxyproline content and Alcian Blue method. Expressions of glycosaminoglycan (GAG), type II collagen and Sox-9 were assayed by real-time fluorescence quantitative PCR. Results: The cultured hUC-MSCs phenotype was CD105+/CD29+/CD44+/ CD31-/CD34-/ CD40-/CD45-/HLA-DR-. hUC-MSCs weakly expressed chondrocyte marker, which strongly expressed GAG and type II collagen after chondrogenic induction, and the cells were incubated in pellet culture with higher expression. Real-time PCR results demonstrated that chondrogenic induction cells were expressed GAG, type II collagen and Sox-9, and the cells were incubated in pellet culture with higher expression. Conclusion: hUC-MSCs incubated in pellet culture is more conducive to differentiate into chondrocytes than those cultured in monolayer culture system.

A full rang of external prestressing CFRP concrete box girder flexural performance have been tested. Crack distribution, deflection,strain distribution, stress increment of external CFRP have been measured. The results demonstrate that that as the load increase, the shear lag phenomenon on the upper and bottom plate of the box girder is more significantly; There is a certain friction Loss on the interface between CFRP and two steering block which arrange in the mid-span. If suitable element models and material constitutive laws are chose, the ANSYS program may simulate the fully flexural experimental process of the box girder, the result is well agree with the experimental result.

A new route to substitute for the traditional two-step method for adipic acid production has been investigated. Supported nano metal catalysts Au/C and Co/C were prepared and used for liquid phase oxidation of cyclohexane to adipic acid with oxygen as an oxidant. These catalysts were characterized by XRD, TEM and ICP-AES. The reactions were carried out in an autoclave with solvent and radical initiator at 373~423K and 1.5 MPa. Au/C (1.25%) was found to be a highly efficient catalyst for the oxidation of cyclohexane with a high conversion (44.93%) of cyclohexane and more than 54.85% selectivity to adipic acid. It is indicated that there was a potential application prospect for the nano-catalysts in one-step oxidation of cyclohexane to adipic acid.

The oxidation of cyclohexane in the microchannels not only improves the safety of the reaction, but also the performance of the oxidation reaction. Different gas-liquid micro mixers were used for the mixing of gas and liquid before entering into microchannels, and SIMM-V2 performed best of all. Excellent slug/plug flow can be formed in the microchannels after mixing in the gas-liquid micro mixer when the molar ratio of oxygen to cyclohexane is less than 0.5:1. The conversion of cyclohexane increased as the residence time increased, but the selectivity of cyclohexanol and cyclohexanone increased first and then decreased. At the reaction temperature of 200 ℃, with the flow rate of the solvent isopropanol being 1 mL/min and the molar ratio of oxygen to cyclohexane being 0.15:1, both the conversion of cyclohexane and selectivity of cyclohexanol and cyclohexanone increased with the increase of pressure. The conversion of cyclohexane and selectivity of cyclohexanol and cyclohexanone reached 10.10% and 66.93% respectively at the pressure of 8 MPa. It is indicated that the new process by use of uncatalyzed cyclohexane oxidation in the microchannels will have very attractive prospects in the improvement of the safety, intensification of the gas-liquid mass transfer and obtaining good reactive performance. Therefore, the technology shows good potential in industrial applications.

Nonlinear dynamic buckling for sandwich shallow conical shell structure under uniform triangular pulse is investigated. Based on the Reissner’s assumption and Hamiton’s principle, the nonlinear dynamic governing equation of sandwich shallow spherical shells is derived. The corresponding nonlinear dynamic response equations are obtained by Galerkin method and solved by Runge-Kutta method. Budiansky-Roth criterion expressed by displacements of rigid center is employed to determine the critical impact bucking load. The effects of geometric parameters and physical parameters on impact buckling are discussed.

The fractional dynamics equation of a viscoelastic two-member truss system, in which fractional derivative model introduced to simulate the materials’ characteristics, is proposed. The equilibrium paths under vertical loads, horizontal loads and combined loads are discussed respectively. The results show that: there are primary and secondary equilibrium paths under vertical and horizontal loads. Bifurcations will occur under combined loads and the ultimate bearing capacity of the system will reduce. The equilibrium paths became complex because of the horizontal disturbance, and the bigger of the horizontal disturbance the smaller of the system ultimate bearing capacity.

A series of supported catalysts Co3O4/SiO2 were prepared by deposition precipitation method. ICP-AES, XRD and TEM data revealed that the Co3O4 active site was highly dispersed on the surface of SiO2. The catalysts were evaluated for selective epoxidation of styrene with molecular oxygen. The results showed that the catalysts were of good catalytic activity for styrene epoxidation and many factors had an evident effect on the catalytic epoxidation activity. The best catalyst was 3% Co3O4/SiO2 on which 96.3% conversion of styrene and 52.7% selectivity of styrene oxide were obtained under the flow rate of O2 20mL/min, 100℃, 10h with solvent.

Through a lot of investigations and studies ,and refering to the current related technical specifications and relevant reference, and combining with the characteristics of the ordinary concrete box section component , single box double room concrete huge section box girder which can realize city bridges double traffic is devised creatively,considering of the need of structure and function. By choosing proper element type and material modle, the designed box grider is modeled by the nonlinear analysis software ANSYS. The shear lag effect of the concrete huge section box girder is studied by applying four load conditions including prestressed load, the upper and lower live load and double load. Parameter analysis are done, which include the load type and width-span ratio.And corresponding conclusions are drawn.

Au/Co3O4 catalysts were prepared by a co-precipitation method and characterized by inductively coupled plasma-atomic emission spectrometry (ICP-AES), transmission electron microscope (TEM) and X-ray diffraction (XRD). The selective oxidation of cyclohexane to cyclohexanone and cyclohexanol was investigated over Au/Co3O4 catalysts using molecular oxygen as oxidant. These catalysts showed higher activities as compared to the pure Co3O4 under the same reaction conditions.

In order to utilize the waste steel slag effectively, three kinds of alkaline activator such as Na2SO4, Na2SiO3, Na2CO­3 were used to prepare steel slag cementitious material and measure its strength of 28 days and 60 days in the standard wet conditions. Microcosmic structure form of hydration products of cementitious material was analyzed by the test of SEM. The results indicate that: three activators on the strength of steel slag all have certain stimulation effect, and Na2SO4 has the apparent stimulation effect on the strength of steel slag, the analysis and test of SEM also shows that hydration products structure form of steel slag cementitious material added with Na2SO4 is much more than other two activators and is more helpful to improve steel slag strength.

Alumina was modified by doping with metal oxide and then used as the support for depositing gold by an impregnation-ammonia washing method to obtain Au/MxOy/Al2O3 (M=Co, Zr and Ce) catalysts. These samples were characterized by inductively coupled plasma-atomic emission spectrometry (ICP-AES), transmission electron microscope (TEM) and X-ray diffraction (XRD). The effects of Co3O4 content, metal oxide and mixed metal oxides on the catalytic activity for the selective oxidation of cyclohexane to cyclohexanone and cyclohexanol using molecular oxygen as oxidant were studied. The results showed that better catalytic performance was obtained over Au/MxOy/Al2O3 catalysts compared with over Au/Al2O3 catalysts. 9.69% conversion of cyclohexane and 93.31% selectivity to cyclohexanone, cyclohexanol and cyclohexyl hydroperoxide, with 1.02 ratio of cyclohexanone to cyclohexanol were obtained over the Au/MxOy/Al2O3 catalyst at 150 , 1.5 MPa for 3 h. Moreover, according to the recycling test, the catalyst could be reused four times without remarkable loss of activity.

Carbon-supported gold catalysts Au/C were prepared by an impregnation-reduction method and modified by AgNO3 to obtain bi-metallic catalysts Au-Ag/C, which were characterized by X-ray-diffraction (XRD) and Transmission Electron Microscope (TEM). Their catalytic performance was tested in the oxidation of cyclohexene in an autoclave without any solvent. The results showed that Ag doping can significantly enhance the catalytic performance of carbon-supported gold catalyst. Au(1.0 wt.%)-Ag(1.0 wt.%)/C has been found to be an efficient catalyst for the cyclohexene oxidation with a conversion of 27.6% at 80 ˚C and 0.4 MPa for 12 h while selectivity for ∑C6 products (including cyclohexene oxide, 2-cyclohexene-1-ol, 2-cyclohexene-1-one and cyclohexane-1,2-diol) exceeding 88.9%, especially the selectivity of cyclohexane-1,2-diol up to 47.6%. Moreover, the effects of Au, Ag content on catalytic performance were also reported.

With wide applications of FRP in civil engineering, it is necessary to study the durability of FRP reinforced concrete structure. Based on the related research both at home and abroad, the factors affecting durability of FRP reinforced concrete structures and the corresponding improvements have been put forward by analyzing the durability of concrete, FRP materials and reinforced structures, respectively.

The major industrial by-product largely generated in southern China is ceramic polishing powder (PP) produced from ceramic industries. In this paper, gross of silicon and aluminum dissolved from polishing powder and fly ash were studied by alkali dissolve experiments, pozzolanic activity of PP and fly ash were studied as well by determining chemical combined water and fast strength experiments. Results show that the cement mortar strength active index of PP is up to 82%. The average size of PP is 6.31 um; the fine granule of PP fills in the pore of mortars and improves the compressive strength of mortars. Microstructure of mortars added PP demonstrates that hydration gel is close-grained, dense and reticular. It reveals that “the granule domino effect” enhance the density of mortars added PP and conduce to the high compressive strength. Polishing powder can be used as cementitious material, especially the quality of early stage is higher than that of fly ash. Gross of vitreous phase is not the single factor to determine pozzolanic quality of polishing powder, ability of alive silicon and aluminum responding to Ca(OH)2 is one of the most important impact.

Objective：To observe the effect of human platelet extracts on proliferation and differentiation of rabbit growth-plate chondrocytes in monolayer and fabrication of tissue engineering cartilage in vitro. Method: To determine the effects of platelet extracts at different concentrations on proliferation and differentiation of rabbit growth-plate chondrocytes using 3H-TdR、PNP and HE staining. Results: Platelet extracts had very strong stimulative effects on proliferation and differentiation of chondrocytes, especially the hypertropization (termination) of chondrocytes.

A full test on the flexible behaviors of the long flanges and trapezoidal section high-strength concrete thin-walled box girder has been performed. The deflection horizontal distribution, strain and strain distribution of concrete and reinforced bars in the compressive flanges, strain distribution along rib height have been studied. The results demonstrate that reinforced concrete thin-walled box girder has fine flexible behavior and ductility, strain distribution along rib height agrees with the basic assume, i.e. Plane section before deforming remain plane, and the destructive experimental results disclosed the full process law of shear lag effect and equivalent calculated coefficient of compressed flange width at middle span section, which can be served as a reference for that applying elementary reinforced concrete beam theory settles the ultimate flexural capacity calculation of concrete thin-walled box girder.