Spermatophyte Flora Distribution in Hubei Daqi Mountain Nature Reserve

A basic ingredient analysis of flora and geographic elements of plant genera and families in Daqi Mountain Nature Reserve was conducted through the field survey and specimen collection,based on the system investigation of plant flora,and an R/T ratio comparison between the flora in Daqi Mountain and adjacent mountain floras was made.Plant taxonomy identification indicates that spermatophytes in the nature reserve comprises 1035 species of 534 genera,falling in 140families,of which 10 gymnosperm species of 8 genera fall in 5 families,while 1025angiosperm species of 526 genera in 135 families.The analysis of flora demonstrates that the region harbors 15 flora distribution types,with high complexity,paleo-flora origin,distinct trait of temperate zone,abundant ingredient of tropical zone,and close connection with the flora of East China.

Process optimization and mechanism study of ionic liquid-based mixed amine biphasic solvents for CO_(2) capture in biogas upgrading procedure

This study focused on enhancing the efficiency of methane upgrading and reducing energy consumption in the biogas upgrading process through the use of biphasic solvents.An aqueous-based biphasic solvent,comprising methyl monoethanolamine(MMEA),N-methyldiethanolamine(MDEA),and 1-butyl-3-methylimidazolium tetrafluoroborate(ItFB),was meticulously prepared.The biogas upgrading effect,regeneration efficiency,regeneration energy consumption,economic viability,selectivity,and phase separation characteristics of this absorbent were systematically analyzed.Various parameters,including different inlet flow rates,stirring rate,methane inlet concentrations,reaction temperatures,and amine mixing ratios,were adjusted to investigate their impact.A comprehensive evaluation was conducted on the biogas upgrading effect and substance migration trends of the biphasic solvent.Optimal process parameters were determined,demonstrating the favorable impact of the biphasic solvent on biogas upgrading.The upgraded gas achieved a methane purity exceeding 96%,and the regeneration energy consumption decreased by 44.27% compared to 30 wt.%MEA,resulting in a more than 50% improvement in economic efficiency.The interaction between the ionic liquid and carbamate facilitated the phase separation process,with carbon enrichment after separation exceeding 95%.This enhancement significantly contributed to the improvement of regeneration energy consumption.The study thus concludes that biphasic solvents,exemplified by the described aqueous-based solution,offer a promising avenue for effective biogas upgrading with notable advancements in economic and energy efficiency.

Porous silica synthesis out of coal fly ash with no residue generation and complete silicon separation

Ordered mesoporous silica materials exhibit enormous potential in industrial production.Since coal fly ash(CFA)is abundant in Si,it has become a green and promising way to utilize CFA by synthesizing porous silica materials.However,the stable crystalline structure of CFA limits the extraction of Si,and the residue is generated during the process of extracting Si.In this work,we proposed a no-residue method to synthesize ordered mesoporous silica out of CFA.Sodium carbonate(Na_(2)CO_(3))was used to reconstruct the crystals of the CFA,and the calcined mixture then directly reacted with the precipitators.This method combined the process of Si extraction and porous material synthesis.In this method,no residue was generated and the silicon in both amorphous and crystalline phases of CFA was fully utilized.By this method,the extraction efficiency of Si was increased from 31.75%to nearly 100%.The as-synthesized mesoporous silica had a highly-ordered pore structure with a space group of la-3d,a surface area of 663.87 m^(2)/g,a pore volume of 0.41 cm^(3)/g,and an average pore diameter of 2.73 nm.The mechanism of crystalline transformation and material structure formation were systematically studied.This method provides a new idea to dispose of CFA and synthesize porous silica materials.

Influence of H_(2)S and NH_(3) on biogas dry reforming using Ni catalyst:a study on single and synergetic effect

Biogas is a renewable biomass energy source mainly composed of CH4 and CO_(2).Dry reforming is a promising technology for the high-value utilization of biogas.Some impurity gases in biogas can not be completely removed after pretreatment,which may affect the performance of dry reforming.In this study,the influence of typical impurities H_(2)S and NH_(3) on dry reforming was studied using Ni/MgO catalyst.The results showed that low concentration of H_(2)S in biogas could cause serious deactivation of catalyst.Characterization results including EDS,XPS and TOF-SIMS confirmed the adsorption of sulfur on the catalyst surface,which was the cause of catalyst poisoning.We used air calcination method to regenerate the sulfur-poisoned catalysts and found that the regeneration temperature higher than 500℃could help catalyst recover the original activity.NH_(3)in the concentration range of 50–10000 ppm showed a slight inhibitory effect on biogas dry reforming.The decline rate of biogas conversion efficiency increased with the increase of NH_(3) concentration.This was related to the reduction of oxygen activity on catalyst surface caused by NH_(3).The synergetic effect of H_(2)S and NH_(3)in biogas was investigated.The results showed that biogas conversion decreased faster under the coexistence of H_(2)S and NH_(3)than under the effect of H_(2)S alone,so as the surface oxygen activity of catalyst.Air calcination regeneration could also recover the activity of the deactivated catalyst under the synergetic effect of H_(2)S and NH_(3).

Influence of SO_2 in incineration flue gas on the sequestration of CO_2 by municipal solid waste incinerator fly ash

The influence of CO2 content and presence of SO2 on the sequestration of CO2 by municipal solid waste incinerator （MSWI） fly ash was studied by investigating the carbonation reaction of MSWI fly ash with different combinations of simulated flue gas. The reaction between fly ash and 100% CO2 was relatively fast; the uptake of CO2 reached 87 g CO2/kg ash, and the sequestered CO2 could be entirely released at high temperatures. When CO2 content was reduced to 12%, the reaction rate decreased; the uptake fell to 41 g CO2/kg ash, and 70.7% of the sequestered CO2 could be released. With 12% CO2 in the presence of SO2, the reaction rate significantly decreased; the uptake was just 17 g CO2/kg ash, and only 52.9% of the sequestered CO2 could be released. SO2 in the simulated gas restricted the ability of fly ash to sequester CO2 because it blocked the pores of the ash.

A REVIEW AND PROSPECT OF READABLE MACHINE PROOFS FOR GEOMETRY THEOREMS

After half a century research, the mechanical theorem proving in geometries has become an active research topic in the automated reasoning field. This review involves three approaches on automated generating readable machine proofs for geometry theorems which include search methods, coordinate-free methods, and formal logic methods. Some critical issues about these approaches are also discussed. Furthermore, the authors propose three further research directions for the readable machine proofs for geometry theorems, including geometry inequalities, intelligent geometry softwares and machine learning.

Leaching characteristics of heavy metals during cement stabilization of fly ash from municipal solid waste incinerators

The leaching characteristics of heavy metals in products of cement stabilization of fly ash from a municipal solid waste incinerator were investigated in this paper.The stabilization of heavy metals such as Cd,Pb,Cu,and Zn in fly ash from such incinerators was examined through the national standard method in China based on the following factors:additive quantity of cement and Na_(2)S,curing time,and pH of leaching liquor.The results showed that as more additives were used,less heavy metals were leached except for Pb,which is sensitive to pH of the leachate,and the worse effect was observed for Cd.The mass ratio of cement to fly ash=10% is the most appropriate parameter according to the national standard method.When the hydration of cement was basically finished,stabilization of heavy metals did not vary after curing for 1 d.The mixtures of cement and fly ash had excellent adaptability to environmental pH.The pH of leachate was maintained at 7 when pH of leaching liquor varied from 3 to 11.

An end-to-end text spotter with text relation networks

Reading text in images automatically has become an attractive research topic in computer vision.Specifically,end-to-end spotting of scene text has attracted significant research attention,and relatively ideal accuracy has been achieved on several datasets.However,most of the existing works overlooked the semantic connection between the scene text instances,and had limitations in situations such as occlusion,blurring,and unseen characters,which result in some semantic information lost in the text regions.The relevance between texts generally lies in the scene images.From the perspective of cognitive psychology,humans often combine the nearby easy-to-recognize texts to infer the unidentifiable text.In this paper,we propose a novel graph-based method for intermediate semantic features enhancement,called Text Relation Networks.Specifically,we model the co-occurrence relationship of scene texts as a graph.The nodes in the graph represent the text instances in a scene image,and the corresponding semantic features are defined as representations of the nodes.The relative positions between text instances are measured as the weights of edges in the established graph.Then,a convolution operation is performed on the graph to aggregate semantic information and enhance the intermediate features corresponding to text instances.We evaluate the proposed method through comprehensive experiments on several mainstream benchmarks,and get highly competitive results.For example,on the SCUT-CTW1500,our method surpasses the previous top works by 2.1%on the word spotting task.