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Vegetation slope protection has become more popular in recent years as an environmentally friendly support approach for slope protection projects. Thus, it's critical to study how to properly plant vegetation to maximize its slope protection effect. As a result, this work uses arbor as the research object and 3D printing technology to construct a model of the arbor root. The slope protection effect of arbor was studied by using a self-designed landslide model test system and conducting systematic physical model tests with three different root arrangement modes and three different root spacings. The results reveal that: ①With tree roots supporting the slope, the peak value of anti-sliding force increases, the time to reach the peak value of anti-sliding force is substantially delayed, and anti-sliding force attenuation is reduced. ②Anti-arch arrangement>positive arch arrangement>linear arrangement>no root support in terms of anti-sliding force improvement. S=1.5D (root coverage range D=7 cm) has a similar improved impact to S= 2.0D, while S=2.5D has the highest peak value of anti-sliding force. ③In terms of the root arrangement mode, the anti-arch arrangement has the most obvious improvement effect on the slope displacement, while the positive arch arrangement and linear arrangement are close in terms of the improvement effect on the displacement. In terms of the root spacing, S=2.5D has the most obvious improvement effect on the slope displacement, while S=1.5D and S=2.0D are close in terms of the improvement effect on the slope. ④Under the linear arrangement, the slope's sliding range expands, whereas the positive arch and anti-arch arrangements effectively limit slope deformation. Root spacing has no obvious effect on the slope deformation field.In conclusion, managing the arrangement mode of trees and root spacing in the vegetation protection project can increase the slope protection effect.

In this paper, a method was proposed to prepare high-purity CaCO3 to sequester CO2 by means of the cyclic utilization of ammonium chloride and with carbide slag as the raw material. There was a systematical discussion about the process conditions for carbonation reaction and the effect of different technological conditions on the property of reaction product. The results have shown that the optimum process conditions for the carbonation reaction were as follows: reaction time: 60 min, reaction temperature: 30 °C, and the flow velocity of CO2: 80 mL/min. The optimum carbonated conversion rate was 98.99 % The resulting product was nanoscale spherical vaterite with a CaCO3 content of 99.95 %, a whiteness of 99.3% and good self-fluidity and self-pulverability. The carbonation reaction filtrate could be recycled 8 times throughout the preparation process, and the reaction efficiency at this time was greater than 50%. High-purity nanoscale CaCO3 and fibrous CaCO3 could be successfully prepared by the control of process conditions. The study scheme proposed herein is hopeful to be used to the extraction of CO2 from carbide slag and the controlled preparation of CaCO3. [ABSTRACT FROM AUTHOR]

Using bentonite as the main raw material, zeolite A was prepared by alkaline melting. The static adsorption experiments were carried out to explore the adsorption kinetics and thermodynamics of Sr2+ on bentonite and zeolite A. The results show that the adsorption capacity of bentonite and zeolite depends on the initial concentration of Sr2+, and the trends of adsorption behavior with respect to the initial concentration and adsorption time is roughly the same for bentonite and zeolite. The isotherm adsorption process of Sr2+ on bentonite and zeolite conforms to the Langmuir isotherm adsorption model. The adsorption mechanism of Sr2+ on bentonite and zeolite is similar, both based on cation exchange adsorption in monolayer. The kinetics of adsorption follows a pseudo-second-order kinetic adsorption process controlled by chemical reaction. The bentonite and zeolite before and after adsorption were characterized by XRD and SEM. The adsorption of bentonite and zeolite in acidic solution did not severely damage or affect their intrinsic framework structures. The adsorption capacity of A zeolite for Sr2+ is about 3.9 times of that of bentonite, showing a better adsorption capability than bentonite. [ABSTRACT FROM AUTHOR]

Objective To analyze the polymorphism of 71 SNP loci on Y chromosome in Han population of Northwest China, to assess its forensic application value, and to screen out Y-SNP loci for forensic examination of Han population in East, South, and Northwest China based on the integration of previous research results. Methods Multiplex polymerase chain reaction （PCR） and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS） were performed on 71 Y-SNP loci of 202 unrelated Han male individuals in Northwest China. Gene diversity （GD） and haplotype diversity （HD） values were calculated, and then Y-SNP loci of Han population in East, South, and Northwest China were screened with the combination of data from previous research. Results Among the detected 71 loci, 67 loci were polymorphic in the Northwest Han male population, with GD values 0.010 0-0.502 2. There were 22 and 25 loci with a moderate （0.2≤GD