The goat’s hind limbs play an important role in dampening vibrations caused by ground impact during movement.Inspired by the unique structure of their hind limbs,a novel bionic limb vibration isolator has been develo...The goat’s hind limbs play an important role in dampening vibrations caused by ground impact during movement.Inspired by the unique structure of their hind limbs,a novel bionic limb vibration isolator has been developed to suppress low-frequency vibrations.It consists of the base,the carrying platform,four bionic legs and so on.The bionic legs are made up of rods of varying lengths and springs in different directions to imitate the various shapes of bones such as the femur and patella of the hind limbs of goats and developed muscles such as the biceps and quadriceps.The bionic device was found to have excellent nonlinear stiffness through statics analysis,and could be flexibly adjusted to the work range and load capacity.The bionic vibration isolator offers lower natural frequencies(2.3 Hz),better vibration isolation effect and a wider vibration isolation band than conventional linear vibration isolator.The bionic device can effectively suppress vibrations above 3.2 Hz and reduce the amplitude of random vibrations to more than 90%.In addition,compared to similar bionic vibration isolation devices,the bionic isolator achieves excellent load-bearing capacity in a smaller size,which facilitates its application in practical production.展开更多
As water reuse development has increased,biological stability issues associated with reclaimed water have gained attention.This study evaluated assimilable organic carbon(AOC)in effluents from a full-scale membrane bi...As water reuse development has increased,biological stability issues associated with reclaimed water have gained attention.This study evaluated assimilable organic carbon(AOC)in effluents from a full-scale membrane biological reactor(MBR)plant and found that they were generally stable over one year(125-216µg/L),with slight increases in warmer seasons.After additional tertiary treatments,the largest increases in absolute and specific AOCs were detected during ozonation,followed by coagulation-ozonation and coagulation.Moreover,UV254 absorbance is known to be an effective surrogate to predict the AOC changes during ozonation.Applying coagulation prior to ozonation of MBR effluents for removal of large molecules was found to reduce the AOC formation compared with ozonation treatment alone.Finally,the results revealed that attention should be paid to seasonal variations in influent and organic fraction changes during treatment to enable sustainable water reuse.展开更多
Y2 Mo4 O15 particles were prepared using a simple solution method（SSM） and used as a highly efficient selective adsorbent for methylene blue（MB） in aqueous solutions. The maximum adsorption capacity of the samples...Y2 Mo4 O15 particles were prepared using a simple solution method（SSM） and used as a highly efficient selective adsorbent for methylene blue（MB） in aqueous solutions. The maximum adsorption capacity of the samples was determined based on the adsorption isotherms with different adsorbent doses at 298,318 and 338 K. The fittings of the temperature-dependent isotherms yield ΔrGm^θ=-34.1 kJ/mol,ΔrHm^θ-36.9 kJ/mol and ΔrSm^θ=-9.67 J/mol·K. The as-prepared Y2 Mo4 O15 has a very large maximum adsorption capacity（i.e., 198 mg/g） for MB at room temperature, and this value is only less than that of amorphous hardwood powder. Notably, 80 mg of adsorbent is able to completely decolorize 250 mL of 30 mg/L MB aqueous solution. The kinetic parameters of the adsorption process were obtained from the temperature-dependent adsorption isotherm（i.e., E1=26.9 kJ/mol and E1 = 63.8 kJ/mol）. The results of adsorption kinetics show that it is a pseudo-second-order reaction. The mechanism of the high selectivity and the large adsorption capacity is discussed based on competitive ion（CI） experiments and coordination theory.展开更多
基金This research was funded by the the Science and Technology Development Program of Jilin Province,China(Grant No.20230101117JC)National Natural Science Foundation of China(Grant No.51775234,91748211,51305157)the Science and Technology Development Program of Jilin Province,China(Grant No.20190302101GX,20180101090JC).
文摘The goat’s hind limbs play an important role in dampening vibrations caused by ground impact during movement.Inspired by the unique structure of their hind limbs,a novel bionic limb vibration isolator has been developed to suppress low-frequency vibrations.It consists of the base,the carrying platform,four bionic legs and so on.The bionic legs are made up of rods of varying lengths and springs in different directions to imitate the various shapes of bones such as the femur and patella of the hind limbs of goats and developed muscles such as the biceps and quadriceps.The bionic device was found to have excellent nonlinear stiffness through statics analysis,and could be flexibly adjusted to the work range and load capacity.The bionic vibration isolator offers lower natural frequencies(2.3 Hz),better vibration isolation effect and a wider vibration isolation band than conventional linear vibration isolator.The bionic device can effectively suppress vibrations above 3.2 Hz and reduce the amplitude of random vibrations to more than 90%.In addition,compared to similar bionic vibration isolation devices,the bionic isolator achieves excellent load-bearing capacity in a smaller size,which facilitates its application in practical production.
基金This work was supported by the Key Program of the National Natural Science Foundation of China(No.51738005)the Youth Program of National Natural Science Foundation of China(No.51908317).
文摘As water reuse development has increased,biological stability issues associated with reclaimed water have gained attention.This study evaluated assimilable organic carbon(AOC)in effluents from a full-scale membrane biological reactor(MBR)plant and found that they were generally stable over one year(125-216µg/L),with slight increases in warmer seasons.After additional tertiary treatments,the largest increases in absolute and specific AOCs were detected during ozonation,followed by coagulation-ozonation and coagulation.Moreover,UV254 absorbance is known to be an effective surrogate to predict the AOC changes during ozonation.Applying coagulation prior to ozonation of MBR effluents for removal of large molecules was found to reduce the AOC formation compared with ozonation treatment alone.Finally,the results revealed that attention should be paid to seasonal variations in influent and organic fraction changes during treatment to enable sustainable water reuse.
基金Project supported by the Fundamental Research Funds for the Central Universities(N162302001)the Basic Key Program of Applied Basic Research of Science and Technology Commission Foundation of Hebei Province in China(15961005D)+2 种基金the Natural Science Foundation of Liaoning Province(2015020665)the Hebei Province Higher Education Research Project(ZD2017309)Northeastern University at Qinhuangdao Campus Research Fund(XNK201602)
文摘Y2 Mo4 O15 particles were prepared using a simple solution method（SSM） and used as a highly efficient selective adsorbent for methylene blue（MB） in aqueous solutions. The maximum adsorption capacity of the samples was determined based on the adsorption isotherms with different adsorbent doses at 298,318 and 338 K. The fittings of the temperature-dependent isotherms yield ΔrGm^θ=-34.1 kJ/mol,ΔrHm^θ-36.9 kJ/mol and ΔrSm^θ=-9.67 J/mol·K. The as-prepared Y2 Mo4 O15 has a very large maximum adsorption capacity（i.e., 198 mg/g） for MB at room temperature, and this value is only less than that of amorphous hardwood powder. Notably, 80 mg of adsorbent is able to completely decolorize 250 mL of 30 mg/L MB aqueous solution. The kinetic parameters of the adsorption process were obtained from the temperature-dependent adsorption isotherm（i.e., E1=26.9 kJ/mol and E1 = 63.8 kJ/mol）. The results of adsorption kinetics show that it is a pseudo-second-order reaction. The mechanism of the high selectivity and the large adsorption capacity is discussed based on competitive ion（CI） experiments and coordination theory.
