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Influence of surface roughness on the development of moss-dominated biocrusts on mountainous rock-cut slopes in West sichuan, China

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Journal of Mountain Science 2023年第8期20卷 2181-2196页

作者： ZHAO Xin-yue ZHAO Mao-qiang WANG Pan-pan DAI Yu-quan PU Wan-qiu HUANG Cheng-min Department of Environmental Science and engineering Sichuan UniversityChengdu 610065China Jiuzhaigou Administration Bureau Jiuzhaigou 623402China sichuan institute of geological engineering investigation Group CO.LTD Chengdu 610072China

Since natural restoration combined with artificial auxiliary measures may achieve a relatively rapid restoration effect at a lower cost, it has become an essential measure for the ecological restoration of rock slopes. Previous studies have focused heavily on the relationship between substrate nutrients and water conditions and the development of mosses on the rock surface, but quantitative characterization of substantial effect of rock surface texture(e.g., microrelief) on moss growth is absent. The undulating microrelief on the rock surface can increase the heterogeneity of the microhabitat, which may be an important factor affecting the development of mossdominated biocrusts. In this study, the roughness of rock surfaces, moss coverage and biomass, weight and major nutrient contents of soils within the biocrusts were measured in the western mountainous area of sichuan Province, Southwest China to further examine the role of rock surface microrelief in the biocrusts. The results showed that three main factors affecting the development of the biocrusts were bryophyte emergence, soil accumulation, and lithology. The presence of moss accelerates soil formation on rock surfaces and lead to the accumulation of nutrients so that all parts of the moss-dominated biocrusts system can develop synergistically. It was found that a microrelief structure with a roughness between 1.5 and 2.5 could gather soil and bryophyte propagules effectively, which may have a strong relationship with the angle of repose. When the roughness is 1.5, the corresponding undulation angle is very close to the theoretical minimum value of the undulation angle calculated according to the relationships between the undulation angle of the protrusion, slope and angle of repose.

关键词： Biocrusts Moss Natural restoration Repose angle Rock slope Roughness

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Effect of crevice density on biological soil crust development on rock cut slope in mountainous regions,sichuan,China

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Ecological Processes 2023年第1期12卷 46-63页

作者： Maoqiang Zhao Wanqiu Pu Jie Du Wenhu Liu Qian Zhang Yanmei Liu Li Xiao Yingwei Ai Chengmin Huang Department of Environmental Science and engineering Sichuan UniversityNo.24 South Section 1Yihuan RoadChengdu 610065China Jiuzhaigou Administration Bureau Jiuzhaigou 623402SichuanChina School of Life Science Sichuan UniversityChengdu 610064SichuanChina sichuan institute of geological engineering investigation Group Co. Ltd.Chengdu 610072SichuanChina

Background The rock cut slope(RCS)could cause damage to regional ecological functions and landscapes and requires *** soil crusts(BSCs)are pioneer and dominant colonizers during the initial recovery *** accelerate the natural recovery of RCS,the development process and influencing agents of BSC should be ***,the area index of crevices(IR),BSC coverage(COV)and biomass(BM),soil weight(SW),and major soil nutrients[organic carbon(OC),total nitrogen(TN)and total phosphorus(TP)]content,collected from 164 quadrats on 13 RCSs in the mountainous area of west sichuan Province,China,were measured,to explore the effect of crevice of RCS on BSC *** Soil OC,TN and TP on RCSs ranged from 18.61 to 123.03 g kg^(-1),0.96 to 6.02 g kg^(-1)and 0.52 to 2.46 g kg^(-1),respectively,and were approximately to or higher than those on natural *** OC,TN and TP contents in soils elevated unsystematically with recovery time of *** on RCS distributed along crevices generally and *** the first 13 years of natural recovery,COV,BM and SW ranged from 6.5 to 28.2%,14.43 to 67.25 g m^(-2),and 127.69 to 1277.74 g m^(-2),***,BM and SW increased linearly with IR on *** positive correlation between COV and BM and IR was insignificantly impacted by bedrock,slope aspect and altitude within the recovery time less than 13 *** and BM on RCSs increased significantly when the recovery time is more than 27 *** Crevice on RCSs could be a major environmental factor which is conducive to BSC development and soil accumulation through creating a space for water and soil ***,with the increase of recovery time of RCSs,BSCs may grow and reach a stable state with the promotion of soil nutrients,plant growth and microbial *** results provide a development process of BSC that from inside to outside the crevices on *** the areas with stable rock strata and a low risk of geological disast

关键词： Rock cut slope Crevice density Natural recovery Biological soil crust Soil organic carbon Soil total nitrogen Soil total phosphorus

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DNA alkylation promoted by an electron-rich quinone methide intermediate

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Frontiers of Chemical Science and engineering 2016年第2期10卷 213-221页

作者： Chengyun Huang Steven E. Rokita Department of Chemistry and Biochemistry University of Maryland College Park MD 20742 USA sichuan institute of geological engineering investigation Chengdu 610072 China Department of Chemistry Johns Hopkins University Baltimore MD 21218 USA

Biological application of conjugates derived from oligonucleotides and quinone methides have pre- viously been limited by the slow exchange of their covalent self-adducts and subsequent alkylation of target nucleic acids. To enhance the rates of these processes, a new quinone methide precursor with an electron donating substituent has been prepared. Additionally, this substi- tuent has been placed para to the nascent exo-methylene group of the quinone methide for maximum effect. A conjugate made from this precursor and a 5＇-aminohex- yloligonucleotide accelerates formation of its reversible self-adduct and alkylation of its complementary DNA as predicted from prior model studies.

关键词： quione methide DNA alkylation reversible covalent reaction bioconjugation target-directed modification of nucleic acids

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Symbol recognition and automatic conversion in GIS vector maps

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Petroleum Science 2016年第1期13卷 173-181页

作者： Dun-Long Liu Zi-Yong Zhou Qian Wu Dan Tang College of Software engineering Chengdu University ofInformation and Technology Chengdu 610225 China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102200China sichuan institute of geological engineering investigation Chenzdu 610072 China

Symbols are considered as the language of a map;hence,accurate understanding of the meaning of symbols is crucial when obtaining geographical information from a map： the symbolisation of spatial data is of key importance in cartography.A geographical information system（GIS） provides a convenient mapping platform and powerful functions for spatial data symbolisation,while the presence of various mapping standards impedes the understanding of maps and sharing of map *** the other hand,the available GIS platforms find it difficult to deal with automatic conversion between maps and different mapping *** resolve this problem,an approach for symbol recognition and automatic conversion is proposed,and a conversion system based on the approach and the Arc GIS Engine platform is developed to realise automatic conversion between maps produced based on different mapping *** test these conversion effects of the proposed system,the petroleum sector is chosen as the research field and the mutual conversion of a map in practical work among the three mapping standards（*** Chinese Petroleum,Shell and USGS standards） governing this field is taken as a *** results show that the conversion system has a high conversion accuracy and strong applicability.

关键词： Symbol symbol matching powerful mutual resolve convenient hence polygon Petroleum

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Newly Discovered Jurassic and Cretaceous Strata in the Yidun Area,SW China and their Constraints on the Mesozoic Tectonic Evolution of the Eastern Tethys

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Acta Geologica Sinica(English Edition) 2015年第3期89卷 1045-1046页

作者： MABI Awei Muhetaer ZARI ZHANG Mingchun WEN Dengkui School of Geology and Mining engineering Xinjiang University institute of geological Survey of sichuan Province

The Yushu-Yidun arc magmatic belt has attracted much attention among geologists due to its complete record of the evolutionary process of the Sanjiang tectonic belt in eastern Tethys and its favorable metallogenic conditions. This belt is composed of the sedimentary rock series, and Late Triassic volcanic- the Indosinian and Yanshanian granite intrusions. It has long been believed that there are no Jurassic or Cretaceous strata in this area.

关键词： process magmatic belt record

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Mechanical Properties and Evolution of Microstructure of Cement Stabilized Loess

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Journal of Renewable Materials 2022年第12期10卷 3611-3627页

作者： Kangze Yuan Kui Liu Guoyang Yi Bowen Yang College of geological engineering and Geomatics Chang'an UniversityXi'anChina China Information Industry engineering investigation and Research institute Xi'anChina School of Civil engineering Chang'an UniversityXianChina

Cement Stabilized Loess(CSL)sample has a long history as a method of improving building *** this paper,the main physical(specific gravity,consistency limit,optimum moisture content,and maximum dry den-sity)and mechanical properties(Unconfined Compressive Strength(UCS)and shear strength par ameters)of CSL samples with different cement content were inves tigated,and the change reasons were exp lored by mean of SEM ***,quantitative analysis sofware Image Pro Plus(IPP)6.0 was used to characterize the microstruc-tural evolution of pores in compacted loess and CSL *** the cement content increased,the specific gravity and optimum water content in the CSL samples increased and the liquid limit and maximum dry density *** plastic limit exhibits an increase followed by a decrease,with the plasticity index changing in the opposite *** UCS and shear strengths of the CSL samples increased with increa sing cement con-tent,and the USC and cement content was better ftted using the Asymptotic model under the same curing *** growth rate of the UCS and shear strength parameters were significantly reduced at cement contents above 2%.The results of Scanning Hlectron Microscopy(SEM)showed that the structure of the CSL samples was denser and had no obvious inter-aggregate ***,compared to compacted loess,produced C-S-H gel and *** analysis of compacted loess and CSL sample by IPP *** to compacted loess,the average pore diameter and average pore area of the CSL sample decreased from 12.44μm and 229.04 μm^(2) to 8.72 μm and 84.68μm^(2),a reduction of 29.9% and 63.0%,*** pore shape tends to fatten,but there is basically no efet on the pore angle ***,a systematic description of the phy-sicochemical reactions occurring during the formation of the CSL sample structure was made,and a schematic diagram of the formation of the CSL sample structure was created.

关键词： Strength pores SEM structure formation quantitative analysis

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Numerical simulation study on penetration performance of depleted Uranium(DU)alloy fragments

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Defence Technology（防务技术） 2021年第1期17卷 50-55页

作者： Fu-lin Zhu Yang Chen Gui-li Zhu sichuan Aerospace System engineering institute Chengdu610100SichuanChina

Due to its high strength,high density,high hardness and good penetration capabilities,Depleted uranium alloys have already shined in armor-piercing *** should also be a lot of room for improvement in the application of fragment killing ***,regarding the performance of the depleted uranium alloy to penetrate the target plate,further investigation is needed to analyze its advantages and disadvantages compared to tungsten *** study the difference in penetration performance between depleted uranium alloy and tungsten alloy fragments,firstly,a theoretical analysis of the adiabatic shear sensitivity of DU and tungsten alloys was given from the perspective of material constitutive ***,taking the cylindrical fragment penetration target as the research object,the penetration process and velocity characteristics of the steel target plates penetrated by DU alloy fragment and tungsten alloy fragment were compared and analyzed,by using finite element software ANSYS/LS-DYNA and Lagrange ***,the influence of different postures when impacting target and different fragment shapes on the penetration results is carried out in the *** results show that in the penetration process of the DU and tungsten alloy fragments,the self-sharpening properties of the DU alloy can make the fragment head sharper and the penetrating ability *** the same conditions,the penetration capability of cylindrical fragment impacting target in vertical posture is better than that in horizontal posture,and the penetration capability of the spherical fragment is slightly better than that of cylindrical fragment.

关键词： Depleted uranium alloy Constitutive model Adiabatic shear Penetration performance Numerical simulation

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Initiation Mechanism of Loess Mudflows by Flume Experiments

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Journal of Earth Science 2022年第5期33卷 1166-1178页

作者： Penghui Ma Jianbing Peng Jianqi Zhuang Xinghua Zhu Cong Liu Yuxiang Cheng Zuopeng Zhang Key Laboratory of Western China Mineral Resources and geological engineering College of Geological Engineering and Surveying of Chang’an UniversityXi’an710054China Xi’an engineering investigation and Design Research institute China Nonferrous Metals Industry Co.Ltd.Xi’an710054China

The structure of loess is loose,and the shear strength of loess drops sharply after contact with ***,loess mudflows have become a common geological disaster on the Chinese Loess *** order to study the initiation mode and mechanism of loess mudflows,in this study,seven sets of flume experiments were designed by controlling the slope angle and rainfall *** results show that(1)when the slope angle is between 10°and 20°,there are two initiation mechanisms of loess mudflows:mudflow(large scale)and retrogressive toe sliding,and mudflow(small-scale)and retrogressive toe sliding.(2)The main method by which water infiltrates into the soil accumulation is mainly vertical infiltration,which is not affected by the slope angle and the seepage direction of the accumulation soil.(3)The liquefaction of loess is the root cause of loess *** infiltrates into the area with an uneven density and a large amount of water accumulates in this ***,the water content of the loess increases and the pore water pressure increases quickly and cannot dissipate in time,so the loess liquefies and the liquefacted area continues to spread and become ***,loess mudflows(large scale)*** increase in pore water pressure was captured in the seven sets of ***,the order of the rising positions in the accumulation were *** requires us to carry out tracking of the particle displacement inside the soil and the spatial changes in the internal structure of the soil in future research.

关键词： flume tests loess mudflow loess liquefaction initiation modes initiation mechanism engineering geology

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Macro-mechanical properties of columnar jointed basaltic rock masses

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Journal of Central South University 2011年第6期18卷 2143-2149页

作者：狄圣杰徐卫亚宁宇王伟吴关叶 institute of Geotechnical engineering Hohai University Kunming investigation and Design institute China Hydropower Engineering Group Co. East China investigation and Design institute China Hydropower Engineering Group Co.

From the geological structure of the columnar jointed rock mass, a visual model was established in software AUTOCAD by programming based on the algorithm of the Voronoi diagram. Furthermore, a program to convert the AUTOCAD model into 3DEC (3-dimensional distinct element code) model was developed, and a numerical model was established in 3DEC. Moreover, the results of triaxial compression tests of columnar jointed rock masses were simulated numerically. The REV (representative element volume) scale was studied, and the result shows that the REV size is 3 m × 3 m. The proposed approach, the established model and the numerical simulation were applied to study the macro-mechanical properties and the equivalent strength parameters of the columnar jointed rock mass. The numerical simulation results are in good accordance with the in-situ test results.

关键词： columnar joint Voronoi diagram three-dimensional distinct element code representative element volume mechanicalparameters

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Waste oyster shell as a kind of active filler to treat the combined wastewater at an estuary

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Journal of Environmental Sciences 2013年第10期25卷 2047-2055页

作者： Hongbing Luo Gu Huang Xiaoying Fu Xiaoling Liu Daocai Zheng Jian Peng Ke Zhang Bo Huang Liangqian Fan Fenghui Chen Xiubo Sun College of Urban and Rural Construction Sichuan Agricultural University China Northwest Municipal engineering Design Research Institute Co. Ltd. State Key Laboratory of Hydraulics and Mountain River engineering Sichuan University Department of Civil and geological engineering University of Saskatchewan

Estuaries have been described as one of the most difficult environments on Earth. It is difficult to know how to treat the combined wastewater in tidal rivers at the estuary, where the situation is very different from ordinary fresh water rivers. Waste oyster shell was used as the active filler in this study in a bio-contact oxidation tank to treat the combined wastewater at the Fengtang Tidal River. With a middle-experimental scale of 360 ma/day, the average removal efficiency of COD, BOD, NH3-N, TP and TSS was 80.05%, 85.02%, 86.59%, 50.58% and 85.32%, respectively, in this bio-contact oxidation process. The living microbes in the biofilms on the waste oyster shell in this bio-contact oxidation tank, which were mainly composed of zoogloea, protozoa and micro-metazoa species, revealed that waste oyster shell as the filler was suitable material for combined wastewater degradation. This treatment method using waste oyster shell as active filler was then applied in a mangrove demonstration area for water quality improvement near the experiment area, with a treatment volume of 5 × 10^3 m^3/day. Another project was also successfully applied in a constructed wetland, with a wastewater treatment volume of 1 ×10^3 m^3/day. This technology is therefore feasible and can easily be applied on a larger scale,

关键词： waste oyster shell active filler combined wastewater treatment tidal estuary engineering application

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