Morphology prediction of dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (TKX-50) crystal in different solvent systems using modified attachment energy model

In order to theoretically study the growth morphology of dihydroxylammonium 5,5’-bistetrazole-1,1’-dio late(TKX-50)crystal in different solvent systems,crystal–solvent models were established,and then molecular dynamics(MD)methods were adopted as a means to simulate particle motion.Modified attachment energy(MAE)model was employed to calculate the growth morphology of TKX-50.The simulation results demonstrate that COMPASS force field and RESP charge are suitable for molecular dynamics simulation of TKX-50.The morphologically dominant growth surfaces of TKX-50 in vacuum are(020),(011),(11–1),(100)and(120),respectively.In water(H_(2)O)and N,N-dimethylformamide(DMF)solvents,the(11–1)face is the largest in the habit face,the growth rate of(020)face becomes faster.With the increase of temperature,the aspect ratios of TKX-50 crystal in DMF solvent increase,and the areas of the(120)faces decrease.In ethylene glycol/H_(2)O mixed solvent system with volume ratio of 1/1,aspect ratio of TKX-50 is relatively small.In formic acid/H_(2)O mixed solvents with different volume ratios(1/4,1/3,1/2,1/1 and 2/1),aspect ratio of TKX-50 is relatively small when volume ratio is 1/2.

A structural relationship between place attachment and intention to conserve landscapes–a case study of Harz National Park in Germany

Place attachment is an important motivation for people to spend more time outdoors and to protect landscapes.This study explores visitors' intention to conserve natural landscapes based on the relationship with their place attachment to National Park landscape. Structural equation modelling(SEM) was used to determine the relationship between landscape conservation and place attachment. A survey with a structured questionnaire was administered to visitors to the seven designated hiking courses of Harz National Park in Germany. The path coefficient of 0.77 revealed that place dependence positively and significantly affected place attachment, whereas place identity did not. Place attachment had a significant effect on both affective appraisals and visiting satisfaction. Higher place attachment led to higher emotional reaction to landscapes on site and higher satisfaction of visiting the park. Among the variables, visiting satisfaction, but not affective appraisals, played a statistically significant mediating role between place attachment and conservation intention. With a path coefficient of 0.86, conservation intention was highly affected by visiting satisfaction. These results suggest that the managers of National Parks should focus on increasing visiting satisfaction based on how visitors are emotionally bonded with their visiting places, in order to enhance the intentions to conserve the landscape of the visitors to National Parks.

Parametric Study on Arc Behavior of Magnetically Diffused Arc

A model coupling the plasma with a cathode body is applied in the simulation of the diffuse state of a magnetically rotating arc.Four parametric studies are performed：on the external axial magnetic field（AMF）,on the cathode shape,on the total current and on the inlet gas velocity.The numerical results show that：the cathode attachment focuses in the center of the cathode tip with zero AMF and gradually shifts off the axis with the increase of AMF;a larger cathode conical angle corresponds to a cathode arc attachment farther away off axis;the maximum values of plasma temperature increase with the total current;the plasma column in front of the cathode tip expands more severely in the axial direction,with a higher inlet speed;the cathode arc attachment shrinks towards the tip as the inlet speed increases.The various results are supposed to be explained by the joint effect of coupled cathode surface heating and plasma rotating flow.