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Abstract: The aminated core-shell organic-inorganic hybrid silica microspheres P( DETA-co-EGDMA)/Si0,were prepared by distilation precipitation polymerization and amide reaction.The diameter of hybrid micro-spheres inorganic core was ca. 400 nm and the thickness of organic polymer shell was ca. 33 nm.The amina-ted hybrid microspheres were characterized by elemental analysis and it was found that N element content ofmicrospheres was 2.91 % .The adsorption behaviors of aminated hybrid microspheres on heavy metal ions Cu(lI) and Pb( II) were investigated,which showed that aminated hybrid microspheres exhibited larger adsorp-tion capacities than methacrylic acid hybrid microspheres P(MAA-co-EGDMA )/SiO2 and unmodified silicamicrospheres.The adsorption isotherm of aminated hybrid microspheres followed the Langmuir model and themaximum adsorption capacities of aminated hybrid microspheres was 45.50 mg/g for Cu(ll) and 70.75 mg/gfor Pb( II) at 298 K,respectively. The adsorption kinetics were consistent with pseudo-second order model.The aminated hybrid microspheres still maintained excellent regeneration ratios through thrice desorption andregeneration experiment.

Abstract: This paper deals with the effect of Sn on the microstructure，physical properties，and welding per-formance of Zn-10Al -xSn Alloys by using OM，XRD diffraction , SEM and its EDS spectrum analyzer andSun10 universal testing machine. The results show that Sn can refine eutectoid structure and reduce the meltingtemperature of Zn-Al alloys. Spreading performance and the shear strength of welded joints are improved withthe adding of Sn element. The spreading area on copper plate is 122 mm’and the shear strength of weldedjoints is 53 MPa when the Sn element is added up to 12 wt. %e . Increasing the adding amount of Sn element,the spreading area and shear strength decrease. This is because intermetallic compound on interfacial growsrapidly.

Abstract: The effects of nano-ZR02 powder on the properties, composition and structure of Al-Si composite Al203-C were studied by using plate corundum aggregate and fine powder, Al powder, Si powder, graphite and nano-Zro2 powder as raw materials and phenolic resin as binder.The results show that the introduction of nano-ZRO2 powder has little effect on the strength of the sample at room temperature and high temperature, but it is beneficial to improve the molding density and oxidation resistance of the sample, and can significantly improve the thermal shock resistance of the sample.The reason for the increase of sample density is that the nano-cobalt oxide has a good filling effect and helps sintering.Nano-zro2 can promote the reaction of Al and Si to generate more non-oxide whiskers, and form a cross-linked network structure in the sample, and the toughening of nano-powder and the phase transition toughening of ZrO2 are conducive to improving the thermal shock resistance of the sample.

Abstract: In this study,polylactic acid ( PLA )-polycaprolactone ( PCL) composite fiber with core-shell struc-ture was fabricated by means of co-axial electrospinning. SEM was employed to study the impacts of electro-spinning voltage,collected distance and ratio of core-shell solution injection speed on morphology of PLA-PCI.composite fiber with core-shell structure. The influences on the formation of the core-shell structure under dif-ferent ratio of core-shell solution injection speed were observed with TEM. The results showed that the obviouscore-shell structure was fabricated when core-shell solution injection speed was 0. 1-0.2 and 0.1-0.3 mL/h.The core component in PLA-PCL composite fiber decreases with the increase of shell solution injection speed.The increasing of electrospinning voltage could efficiently reduce the average diameter of composite fiber. Theaverage diameter of composite nanofiber decreases and then increases with the increase of collection distance.

Abstract: ZSM-5 zeolite with different Si/ Al ratios was selected as catalyst carrier and the salt of the NaAICl,as the surface load.The catalytic performance with different Si/Al ratios at different temperatures was com-pared to investigate the effects of Si/ Al ratio. Commonly used,the catalysts were characterized by X-ray dif-fraction (XRD),GC,scanning electron microscope ( SEM),BET and NH, -TPD and so on. The catalystwhich Si/ Al ratio was 38 had the greatest acidity and was the most active one. The results showed that the cat-alytic activity depended on the surface area at low temperature,while at high temperature depended on the ac-tivation sites.When Si/ Al ratio was 38,at 373 K,Cat-4% showed the best catalytic effect,of which yield ofdichlorodimethylsilane was 57. 9 % .

Abstract: The properties of asphalt emulsifier in micro-surfacing are an issue of great importance for modifiedemulsified asphalt and mixture performance. In this paper,a kind of zwitterionic surfactant which can be usedfor asphalt emulsifier was synthesized by using oleic acid,polyamine,acid and alcohol containing chloride asstarting materials.The synthesized asphalt emulsifier was characterized by means of FT-IR,surface tensionand the calculated hydrophilic- lipophilic balance ( HLB) value. The properties of 5% SBS modified emulsionasphalt and the technical parameters of slurry mixtures were also tested. The results showed that the criticalmicelle concentration (CMC) of emulsifier was 2.63 ×10~3 mol/ L, the surface tension at CMC was 46.1l mV/m,and the calculated HLB value was 12.7. Furthermore, the modified emulsion asphalt showed the best perform-ance when the concentration of emulsifier was 1.5%,and the modified asphalt emulsion evaporation residue25 ℃ penetration was 6.2 mm,softening point was 78.5 ℃ , 5 ℃C ductility was 35 cm;micro-surfacing mix-ture 60 min cohesion value reached 2.4 N · m,moderate molding,1 h and 6 h soaking wet wheel abrasionvalues were to meet regulatory requirements.

Abstract: In order to investigate nitrogen release characteristics of the nanoscale humic acid fertilizers,cellu-lar automata and the spread of fertilizer nutrients discreteness were used as simulation tools and theoretical ba-sis,respectively. Nitrogen dynamic visual simulation was systematically studied by nitrogen migration ofnanoscale humic acid fertilizer. The research results showed that the nitrogen release characteristics of cellularautomata simulation was consistent between nanoscale humic acid fertilizer and the selection of two kinds ofcoated fertilizer under 25°℃. This model provides an effective simulation tool for studying the features in fertil-izer nitrogen released characteristics.

Abstract: Variable angle helical baffle heat exchanger is proposed to optimize the non-fully developed sectionin shell inlet. The flow and heat transfer performance of heat exchangers with different forms of helical baffleswere studied,and the mechanisms of heat transfer enhancement for heat exchangers were analyzed. The resultsshow:the length of non-fully developed section could be reduced by using variable angle helical baffle,the in-tensity of overall helical flow and the coordination of temperature field with velocity field increase too,and thenthe heat transfer performance is strengthened.Compared with general helical baffle heat exchanger,the com-prehensive performance of variable angle helical baffle heat exchanger with angle of 10° +20° and 15° +25°could increase 7.10%~7.54% and 2.88 ~4.05%,respectively.

Abstract: The thermal model using EES (Engineering Equation Solver) is developed,and then the systemperformance of transcritical R744/R290 heat pump water heater is simulated with the meteorological andhydrological conditions in Zhengzhou,the typical city in central China. The total Equivalent Warming Impacts(TEWIs) are calculated with the simulation datum. The results show that the maximum heating system COP is4.104 under the design condition without consideration of internal heat exchanger. When R744/R290 heatpump water heater is on operation in cnetral China,the mean annual heating COP of 4.202 can be achieved.Compared with the hot water heater using other energy,the R744/R290 heat pump water heater is averagelydecreased by 36.39% in the CO,emissions. It is also cacalated and discussed how the internal heat exchangerand compressor isentropic efficiency influence the system performances respectively. Therefore,the R744/R290 based heat pump water heater is characterized by a higher energy efficiency and a very effective way forremarkably reducing CO,emissions.

Abstract: Based on the solar energy-lithium bromide solution desiccant-regeneration test system,the influenceof a range of factors at an inlet,such as solution mass fraction,solution temperature,liquid-gas ratio,relativehumidity ratio of air and temperature,on export air moisture content were analyzed with the orthogonal experi-ment method in the experiment. The results show that the influence degree of them on the capacity of dehu-midification from large to small is:relative moisture content air,liquid-gas ratio,liquid solution temperature,solution mass fraction,and the inlet air temperature. When liquid-gas ratio of the inlet was 3. 5,the systemhad a better dehumidification effect.Meanwhile,based on the flash principle,the regeneration temperature ofthe solution system could be controlled within the range of 60 ℃C and 70 ℃. The results provide the basis forthe engineering design and application of the solar energy-lithium bromide solution dehumidifier.

Abstract: The unilateral bolt connection nodes of new type concrete filled steel tubular columns with outershell and steel beam was put forward by summing up the previous deficiency of connection nodes. Based on theexperimental and theoretical analysis,in consideration of the initial geometric imperfections of steels and con-crete damaged plasticity model,end-plate connections for concrete filled steel tubular columns and steel beamwith outer-shell and without outer shell finite element models were established respectively.Under monotonicloading in finite element model,analysis the damage and working mechanism; according to parametric study a-nalysis the main factors of initial stiffiness and bearing capacity for joints and establish M-0,practical model fornew type joints. The results show that the joints with outer-shell have greater initial stiffness and bearing ca-pacity and better seismic performance.The M-0,models which was presented in this paper are reasonable andreliable.It can provide a reference for theory design and real engineering application.

Abstract: In this study,a theoretical research on hysteretic behavior of a new composite frame composed ofRC column encased steel-tube and steel reinforced concrete beam was proposed by using the plane nonlinearsoftware-IDARC2D. The theoretical analysis results were compared with experiments. In addition,seismic re-sponse regarding to an outer-jacketing reconstruction example of composite frame was analyzed by means oftime-history analysis. The research results showed that IDARC 2D could preferably simulate the entire loadingprocess on the composite frame,and provide a suitable analytical method for hysteretic behavior. The emer-gence sequence of plastic hinges on this frame is ‘beam ends before and column bottoms after’,so that theanti-collapse ability of the structure was largely enhanced.

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