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The double-layered PVA/nanohydroxyapatite (nHA)-poly (vinyl alcohol)(PVA)-sodium alginate (SA) porous composite scaffolds used as synthetic articular cartilage were prepared by the freeze-thawing method, gas foaming method and crosslink method of Ca2+ ion, i.e., upper PVA layer for the cartilage substitute and underlying SA30 porous hydrogels for bone bonding. The microstructure and morphology of composite hydrogels were characterized using scanning electronic microscopy (SEM).It had high porosity and uniform pores. The content of HA in SA30 matrix were tested by Energy-dispersive X-ray spectroscopy (EDS). The biological properties of the composite hydrogels had been evaluated by co-culture and MTT. All results indicate that the PVA/SA30 hydrogels has good potential for repairing or replacing articular cartilage.

For the existence of carbon emission reduction cost, the retail price of the products is so high that the market demand is low, which restricts the promotion of low-carbon products. On the background of a bilateral-monopoly supply chain consisting of a single manufacturer and a single retailer, we establish Stackelberg models based on the carbon emission reduction cost-sharing. And we analyze the changes of the order quantity, the profits of each member and the whole supply chain before and after the implementation of the carbon emission reduction cost-sharing contract. According to the research, when the carbon emission reduction cost-sharing contract is introduced into the model, it leads to a good consequence that the optimal order quantity of the low-carbon product increases, the retail price decreases, and the manufacturer and the retailer will get Pareto improvement on certain condition. Then we derivate the necessary conditions that the profit of the retailer and the manufacturer could both increase.

The phenomenon of free warehousing service offered by integrated transportation and warehousing company is concerned. The mechanics is studied based on the theory of the resource integration and the contract design. The result shows that the transportation company willing to pay the warehouse a certain lump sum on the contract designed. It is shown that the effective contract design is a significant managerial tool to improve cooperative behavior of supply chain.

Facility location problems arise for planning and stationing serve centers including waste disposal sites, hospitals, distribution centers, post offices, and fire stations. The single facility location problem can be modeled by a fixed point problem. Commonly the definition set of variables are requested as a convex set. In real world applications, the collection of feasible sites to locate always is non-convex set. The contribution of this paper is to apply the theorem of existence of the solution of fixed point problem to discuss the facility location problem in non-convex definition set of variables and obtain the computational result. Numerical example shows that the numerical method by tracing the homotopy pathway with predictor-corrector is an effective method to solving the facility location problem and a global optimal solution can be obtained.

Salt slurry is the semi-solid waste of the salt industry. The study object was the salt slurry before filter in Jianghan Salt & Chemical Complex. In laboratory, this study investigated the application of the salt slurry in Talimu high density drilling fluid which composed of KCl-saturated brine and polybasic alcohol. It indicates that on the premise of the same density and pH value as the basic drilling fluid recipe, when the salt slurry dosage is less than 500 kg/m3, all the salt slurry application-based recipes measure up both the rheology behavior and the filtrate loss of the drilling fluid. This investigate will reduce the cost of the drilling fluid with the salt slurry as a resource.

Taking Shiyang River Basin as study area, Considering that the road net building is influenced by the industry, structure of resources, the road building policy, the highway net construction policies and the other transport patterns, so a concept of highway dependence-preference index is put forward, which is used to explain the variation between the actually obtained highway net densities and the values obtained by model calculation. The results show that:The density of road network in Shiyang River Basin is outward decay along the center of Jinchang and Wuwei City. The distribution density of road network is zonal shape from the south of Tianzhu county extending to the Jinchuan District, Jinchang City. Social developments of the Shiyang River Basin depend on the road network strongly, with two Counties/Districts in the super dependence or super preference situation, 28 towns in strong dependence or strong preference situation, which accounting for 26.67% of all townships in Shiyang River Basin. The medium dependence or medium preference situation is about 44 towns, which accounting for 41.9% of all counties in Shiyang River Basin. 24 countries/districts are in the less dependent or weak preference, and 7 countries/districts are in the weak dependent or weak preference situation. Besides, the study also found that the counties city center also formed basically a small group of road network, the region and part of key towns may become a potential area of the density of road network development in the future.

The study takes Shiyang River Basin as a study area, and bases on resource environment-population, social economy-ecological environmental stress and response, and combines the present situation of ecological environment in Shiyang river basin as well as its influencing factors to construct the comprehensive evaluation index.The results show that:(1)The quality of eco-environment in Shiyang River Basin is low, and it shows the descendent trend year by year. The comprehensive evaluation index of ecological environment decreased from 5.05 in 2000 to 3.70 in 2012.(2)Seen from spatial distribution, the order of the descending degrees of the comprehensive evaluation index of ecological environment in Shiyang river basin in recent year is Yongchang County, Su yugur autonomous county, Liangzhou district, Gulang county, Tianzhu Tibetan autonomous country, Minqin county and Jinchuan district.(3) Inside the Shiyang River Basin, because of the dual effects from natural conditions and human activities, the eco-environment in the main ecological barrier regions such as Minqin and Wuwei oasis have changed obviously, especially in MinQin oasis.

[Pb0.95(La0.6Bi0.4)0.05][Zr0.53Ti0.47]O3 (PLBZT) ferroelectric thin films have been synthesized on ITO-coated glass by sol-gel processing. Effects of annealing temperature on structure and properties of PLBZT have been investigated. With the increase of annealing temperature from 500°C to 550°C, the remanent polarization Pr increase slightly to the maximum value of 25.4μC/cm2 due to the improvement in crystallization of PLBZT films. However, when the annealing temperature is more than 550°C, the pyrochlore phase appear and degrade the Pr of PLBZT thin films. The lowest leakage current density of 1.8×10-9 A/cm2 can be observed in PLBZT thin films when the annealing temperature is 550°C.

This paper presents an improved ultra-wideband monocycle pulse generator circuit based on step recovery diode. This pulse generator circuit uses short-circuit microstrip transmission line to generate the Gaussian pulse the monocycle pulse. The improved pulse-shaping network employs two schottky diodes and a MESFET to suppress the pulse ringing. The SRD model was built in RF simulation software ADS, and then the design and simulation of the pulse generator circuit was accomplished using this model. The experiments showed an monocycle pulse of 400ps pulse width with good symmetry. The measured results agreed with the simulation.

During the process of laser cladding thin-walled components, warping deformation generated on the thin-walled components due to the difference between the change of temperature field and thermal expansion coefficient of materials. Through the micro-forging regulation, the internal stress of laser cladding layers changed, reaching the purpose of suppressing the warping plastic deformation generating on the thin-walled components. This paper utilized Ansys software to calculate the temperature field and stress field of the process of laser cladding 304 stainless steel regulated by micro-forging, and compared to the measurement result of the warp deflection and stress. The results indicated that reasonable effective micro-forging can effectively restrain the warp occurring on the thin-walled components treated by laser cladding.

The planetary reducer has both internal incentive of varying mesh stiffness and external incentive of eccentric quality, which are prone to vibration and noise at work. This paper use ANSYS Workbench to build model, divide grid and carry out modal analysis for transmission gear train of Planetary reducer, and calculate the 6 order modes. The modal analysis result is compared with excited frequency and natural frequency respectively. This paper’s modal analysis is more accuracy, more rational and more scientific than the previous experience design and statics analysis. It not only provides the useful date for acoustic analysis of planetary reducer, but also provides theory basis for avoiding planetary reducer resonance, and lays a foundation for the whole system dynamic response calculation and analysis.

The inclusion complexes of rutin/sulfobutylether-β-cyclodextrin (SBE-β-CD) were prepared by grinding, co-precipitation and ultrasonic method and then identified with differential scanning calorimetry (DSC) and UV-visible spectrophotometry (UV). The molar ratio 1∶1 of rutin to SBE-β-CD in the complex was confirmed by phase solubility studies, and the dissolutions of rutin/SBE-β-CD were investigated by UV. The dissolution of rutin included in the complex showed significant increases in aqueous solution. The rutin/SBE-β-CD inclusion complex exhibited unique physical characteristics that are different from rutin.

A series of LiY(WO4)(MoO4):Eu3+red phosphors have been synthesized by solid state reactions at high temperatures. The effect of Eu3+doping concentration, calcination temperature, reaction time and ratio of W/Mo on the optical properties of the red phosphors are studied and optimized. The phase impurity and spectroscopic properties are characterized by X-Ray Diffraction (XRD) and Photo-Luminescence (PL) spectra respectively. It is found that all the samples can be excited efficiently both by near ultraviolet light (395 nm) and blue light (464.5 nm), which match well with the emission of GaN based LED chips. The luminescent intensity maximizes for the sample of Eu3+5 mol % in doping concentration (replacing Y) and W:Mo=1:1 in mole with calcinated of 750°C. To improve the dispersion and change the morphology of the phosphor powders, the sample is post-processed through ultrasonic dispersing method and the luminescent intensity of the post-treated sample increases by nearly 20%.

Salvianolic acid B has many important pharmacological activities. A novel synthetic route of methyl acrylate derivative—an important intermediate to synthesize salvianolic acid B, was designed, and the target compound was prepared in seven steps of reactions with 2-bromo-3-hydroxy-4-methoxybenzaldehyde as major starting material. Its and other four important unreported intermediates’ structures were characterized by IR, 1H NMR, MS, etc.

Salt slurry is the solid waste of the salt industry. The study object is the salt slurry in Jianghan Salt & Chemical Complex. This study investigates the application of the salt slurry in high density polymer saturated brine-based drilling fluid. This laboratory study indicates that the salt slurry may improve the rheology behavior of the drilling fluid, and may measure up both the API and the HTHP filtrate loss. On the premise of the same density and pH value as the basic drilling fluid recipe, with the increasing of the salt slurry, the YP/PV value increased, but the friction coefficient of the mud-cake increased. This investigate will reduce the cost of the high density polymer saturated brine-based drilling fluid with the salt slurry as a resource, and will have important significance for both recycling economy and the cleaner production of the salt industry.

Micro-plastic deformation was produced on the surface of the laser cladding layer by micro-forging, thus cracks were healed in cladding layer; in order to reduce the thermal stress, preheating the substrate was needed to reduce the temperature gap between cladding layer and substrate. In this paper, temperature field by micro-forging on laser cladding Ni60 layer was simulated on software named DEFORM-2D. Compared the width of cracks, the results showed that reasonable and effective preheating temperature could ensure to reduce or eliminate cracks on laser cladding layer.

With 2-pyrrolyltrichloroacetone as major starting material, unreported 1H-3,4-dihydropyrrolo- [1,2-a]pyrazin-1-one was prepared successively by its monoesterification with ethylene glycol, bromine displacement of hydroxy group, cyclization to lactone and its amidation. Unreported 7-aroyl-1H-3,4-dihydropyrrolo[1,2-c][1,4]oxazin-1-one compounds were also synthesized in turn by 2-pyrrolyl-trichloroacetone’s Friedel-Crafts acylation and cyclization. Their structures were characterized by IR, 1H NMR, 13C NMR, MS, HRMS, etc.

In the whole process of micro-forging regulation laser cladding layer, the microstructure structure of cladding layer would change. In order to establish the microstructure evolution of the whole process, firstly re-crystallization model was set up based on Avrami equation and experimental data, and various material constants were gained with regress; secondly calculation for the model was carried out on DEFORM-2D,then the results were compared with experimental data, which showed that calculation results of this model kept good consistency with experimental data, and proved that the model could be applied in a full size finite element simulation of the micro forging process.

Mg0.2Zn0.8O:Al ceramics with high density using nano scale ZnO, MgO and Al2O3 powders as raw materials were obtained by pressureless sintering. The influence of presintering powder and sintering temperature on microstructure of Mg0.2Zn0.8O:Al ceramics were studied. The experiment indicated that presintering powder might decrease produce of the second phase nucleation. The grain size became gradually larger and density of ceramic became obviously higher from 1100°C to 1300°C, but the rising-trend became slower after 1300°C. The Mg0.2Zn0.8O:Al ceramics with high density and homogeneous structure can be made at 1300°C for

Salt slurry is the solid waste of the salt industry. The study object is the salt slurry before filter in Jianghan Salt & Chemical Complex. This study investigates the application of the salt slurry in Talimu unsaturated brine-based drilling fluid of the carboniferous system in laboratory. It indicates that on the premise of the same density and pH value as the basic drilling fluid recipe, when the salt slurry dosage was less than 500 kg/m3, all the salt slurry application-based recipes measured up both the rheology behavior and the filtrate loss of the drilling fluid. This investigate will reduce the cost of the drilling fluid with the salt slurry as a resource.

Chitosan/cellulose acetate multimicrospheres (CCAM) were prepared by the method of W/O/W emulsion with no toxic reagents and had the size interval of 200--280µm. It was investigated as an ideal alternative to enhancement the adsorption of water-soluble dyes from wastewater. The correlation coefficients of adsorption isotherm showed that the Freundlich model was comparable to the Langmuir model. The 1/n was lower than 1.0, indicating that malachite green was favorably adsorbed by CCAM. Furthermore, the amount of malachite green absorbed steeply increased with increasing time and reached plateau values within 2 h and increased with increasing of initial concentration of malachite green from 5 to 25 mg/g.

The effect of grating structure on the photoelectric conversion efficiency of solar cells is studied with the finite-difference time-domain method. The influence of grating shape, height and the thickness of coated metal film is analysed. It is found that the variation of grating shape and height makes great changes of energy storage, especially of the photoelectric conversion efficiency and energy storage of the triangle grating. The comparison between un-optimized and optimized surface grating structure on solar cells shows that the optimized grating surface significantly increases the energy storage capability and greatly improves the efficiency.

Bulldozer transmission and control of physical energy involved in a variety of forms, many parts of local parameters for the overall performance of mutual coupling, and it is difficult to quantify. To solve the bulldozer engineering machinery represents more conditions, more energy state, and difficult to quantification, this paper integrated chassis, ground mechanics, mechanical, hydraulic, hydraulic transmission and other theories, the use of mechanical ,electronic and hydraulic integration design space thought, a hydraulic transmission system model bulldozer is established. For the dynamic performance of the hydraulic drive bulldozer prototype test, testing and simulation complement each other, through the test results to verify the accuracy of models and simulation, through the simulation to make up for poor reproducibility of test defects. To achieve the applications of engineering in typical models, the performance analysis platform of hydraulic drive bulldozer has been developed.

Intergrowth-superlattice-structured SrBi4Ti4O15–Bi4Ti3O12(SBT–BIT) films prepared on p-Si substrates by sol-gel processing. Synthesized SBT–BIT films exhibit good ferroelectric properties. As the annealing temperature increases from 600°C to 700°C, the remanent polarization Prof SBT–BIT films increases, while the coercive electric field Ecdecreases. SBT–BIT films annealed at 700°C have a Prvalue of 18.9µC/cm2which is higher than that of SBT (16.8µC/cm2) and BIT (14.6µC/cm2), and have the lowest Ecof 142 kV/cm which is almost the same as that of SBT and BIT. The C-V curves of Ag/SBT-BIT/p-Si heterostructures show the clockwise hysteresis loops which reveal the memory effect due to the polarization. The memory window in C-V curve of Ag/SBT-BIT/p-Si is larger than that of Ag/SBT/p-Si heterostructure or Ag/BIT/p-Si heterostructure.

Micro-plastic deformation is produced on the surface of the laser cladding layer by micro-forging, and crack makes a change in cladding layer. In this paper, a finite element model with a simplified panel strain model elastic-plastic of stress and strain relationship and adaptive meshing technique was used to simulate laser cladding layer crack by using DEFORM-2D software. Laser cladding process of cracks by micro-regulation forging is simulated. Comparing to the measurement of crack width, the results show that micro-forging can make the surface of laser cladding layer the residual tensile stress to adjust compressive stress, and the micro-forging can significantly reduce or eliminate the laser cladding layer crack. Reasonable and effective regulation of high-frequency micro-forging can improve the surface quality in micro-cladding layer.

This paper utilized self-made high-frequency micro-forging machine to treat NiCrBSi alloy cladded by laser, Optical Microscopy(OM) to study geometric characteristic of plastic deformation, OM and SEM to observe influence on surface microstructure and cracking behavior of the laser cladding layer under micro-forging. The results have shown that: Regularly dendrite microstructure, which is peculiar of laser cladding layer, was broken into pieces. Cracking behavior of laser cladding layer improved greatly.