Compositional and Structural Difference of Fulvic Acid from Black Soil Applied with Different Organic Materials: Assessment After Three Years

Knowledge of different effects of various organic materials on soil humic substance is important for both environmental safety and sustainable agriculture.A pot experiment was conducted at Jilin Agricultural University,Jilin Province in northeast China to discover the influence of herb residue,animal excrement,woody residue,animal remnant on fulvic acid（FA） composition and structure using differential thermal analysis-thermogravimetric（DTA-TG）,fourier transform infrared spectroscopy（FTIR） and elemental analysis.DTA-TG showed the range of peak temperature in the first exothermic reaction increased following the trend： CK〉herb residue〉animal excrement〉woody residue=animal remnant,and the most weight loss was observed in animal excrement.Moreover,the second exothermic reaction of CK-and animal excrement-FA was presented as double peaks,the order of weight loss in that area was animal remnant〉CK〉woody residue〉animal excrement〉herb residue.According to FTIR,herb residue displayed higher adsorption intensity at 2 950,1 420,1 240 and 1 030 cm-1,animal excrement was in reverse.At the same time,herb residue-and animal excrement-FA had an absorption peak at 1 720 cm-1,while other organic materials didn＇t have this peak.As elemental analysis showed,FA isolated from various treatments was significantly distinct.It was clearly shown from our results that FA composition and structure in amended soils may be affected in different ways and at various extents on dependence of the nature and origin of amendment.

Seismic performance evaluation of water supply pipes installed in a full-scale RC frame structure based on a shaking table test

As an important part of nonstructural components,the seismic response of indoor water supply pipes deserves much attention.This paper presents shaking table test research on water supply pipes installed in a full-scale reinforced concrete(RC)frame structure.Different material pipes and different methods for penetrating the reinforced concrete floors are combined to evaluate the difference in seismic performance.Floor response spectra and pipe acceleration amplification factors based on test data are discussed and compared with code provisions.A seismic fragility study of displacement demand is conducted based on numerical simulation.The acceleration response and displacement response of different combinations are compared.The results show that the combination of different pipe materials and different passing-through methods can cause obvious differences in the seismic response of indoor riser pipes.

不同材质管道定向钻穿越过程最大允许长度探讨

在天然气管道定向钻过程中,不同材质管道所承受的拖拉力不尽相同,导致不同材质的管道最大回拖允许长度不同,本文通过分析钢质管材和聚乙烯管材定向钻穿越过程中的最大允许拖拉力、从而确定不同管材的最大回拖允许长度,为工程实际运用提供理论支持。

Ground reaction curves for circular excavations in non-homogeneous,axisymmetric strain-softening rock masses

Fast methods to solve the unloading problem of a cylindrical cavity or tunnel excavated in elasto-perfectly plastic, elasto-brittle or strain-softening materials under a hydrostatic stress feld can be derived based on the self-similarity of the solution. As a consequence, they only apply when the rock mass is homogeneous and so exclude many cases of practical interest. We describe a robust and fast numerical technique that solves the tunnel unloading problem and estimates the ground reaction curve for a cylindrical cavity excavated in a rock mass with properties depending on the radial coordinate, where the solution is no longer self-similar. The solution is based on a continuation-like approach(associated with the unloading and with the incremental formulation of the elasto-plastic behavior), fnite element spatial discretization and a combination of explicit sub-stepping schemes and implicit techniques to integrate the constitutive law, so as to tackle the diffculties associated with both strong strain-softening and elasto-brittle behaviors. The developed algorithm is used for two practical ground reaction curve computation applications. The frst application refers to a tunnel surrounded by an aureole of material damaged by blasting and the second to a tunnel surrounded by a ring-like zone of reinforced(rock-bolted) material.

Structural,electrochemical and cycling properties of Nb^(5+)doped LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)cathode materials at different calcination temperatures for lithium-ion batteries

LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)cathode material is prepared by sol-gel method and the effects of Nb^(5+)doping and different calcination temperatures on cathode materials were deeply investigated.Structural and morphological characterizations revealed that the optimal content of 1 mol%Nb^(5+)can stabilize layered structures,mitigate Ni^(2+)migration to Li layers,improve lithium diffusion capacity,and reduce lattice expansion/shrinkage while cycling.And calcination temperature at 800℃can not only ensure good morphology,but also suppress the mixed discharge of lithium and nickel in the internal structure.Electrochemical performance evaluation revealed that Nb^(5+)doping improves the discharge-specific capacity of the material,which is conducive to ameliorating its rate capability and cycle performance.And the material at 800℃exhibits the highest discharge specific capacity,the best magnification performance,low polarizability,and the best cycle reversibility.

The Feasible Design of Quasi-Solid-State Aqueous Tin-Iodine Batteries

Aqueous rechargeable batteries with high safety have been considered as the main energy source to power portable and wearable electronics.Herein,we report the first construction of quasi-solid-state aqueous tin-iodine batteries by exploiting Sn foil as anode,carbon cloth as cathode,and gel electrolytes.The anode reversibly converts from K_(2)Sn(OH)_(6) to metal Sn,thus eliminating the formation of metal dendrites.Meanwhile,gel electrolytes alleviate anode corrosion and enhance the utilization of the anode.Therefore,the asfabricated quasi-solid-state batteries manifest an areal capacity of 700μAh cm^(-2)(211 mAh g^(-1) equal to theoretical capacity)and excellent cycling stability without obvious capacity degradation after 120 cycles at 1mA cm^(-2).Remarkably,the designed batteries sealed by different package materials including plastic,glass,wood,and cardboard operated steadily,thereby enlarging the application scenario for these batteries.This work enriches the family of aqueous rechargeable batteries and sheds light on the construction of high-performance quasi-solid-state aqueous batteries.

A modeling study of different kinds of sessile droplets on the horizontal surface with surface wettability and gravity effects considered

Droplet phase change is important for energy storage and saving technology.The initial profile of the droplet is extremely important for its vaporization or solidification on a horizontal surface.To understand the effect of liquid physical properties on droplet profile,a theoretical model was developed in this study,based on the Young-Laplace equation with gravity effect specially considered.After the model was experimentally validated by comparing the geometric shape of water droplets,it was further used for predicting droplet shapes of other materials,and thus analyzing the influence of different physical properties,such as temperature,pressure,surface wettability,etc.Results show that the results of this model agree well with the experimental data.The maximum and average deviations are less than 4.5%and 1.5%,respectively.For all kinds of droplets on the fixed surfaces,when the temperature increases,the droplet contact radius increases and height decreases.The droplets of nitro-gen and carbon dioxide are more sensitive to temperature than ethanol and ethylene glycol droplets.For 20𝜇L droplets on the surface of contact angle 150°,when the temperature changes from 273.15 K to 293.15 K,the droplet contact radiuses increase by 30.6%for carbon dioxide,1.2%for ethanol and 0.67%for ethylene glycol,and the droplet heights decrease by 42.9%,2.5%,1.1%,respectively.Results of this study are meaningful for predicting the phase change process of droplets on the horizontal surface by controlling their initial profiles.