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Constructing globally consecutive 3. conductive network using P-doped biochar cotton fiber for superior performance of silicon-based anodes

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Journal of Materials Science & Technology 2024年第6期173卷 181-191页

作者： Jun Cao Jianhong Gao Kun Wang Zhuoying Wu Xinxin Zhu Han Li Min Ling chengdu Liang Jun Chen Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China institute of Zhejiang University-Quzhou Zheda Road 99Quzhou 324000China

The inferior conductivity and drastic volume expansion of silicon still remain the bottleneck in achieving high energy density Lithium-ion Batteries(LIBs).The design of the three-dimensional structure of electrodes by compositing silicon and carbon materials has been employed to tackle the above challenges,however,the exorbitant costs and the uncertainty of the conductive structure persist,leaving ample room for ***,silicon nanoparticles were innovatively composited with eco-friendly biochar sourced from cotton to fabricate a 3. globally consecutive conductive *** network serves a dual purpose:enhancing overall electrode conductivity and serving as a scaffold to maintain electrode *** conductivity of the network was further augmented by introducing P-doping at the optimum doping temperature of 3.0}℃.Unlike the local conductive sites formed by the mere mixing of silicon and conductive agents,the consecutive network can affirm the improvement of the conductivity at a macro ***,first-principle calculations further validated that the rapid diffusion of Li^(+)is attributed to the tailored electronic microstructure and charge rearrangement of the *** prepared consecutive conductive Si@P-doped carbonized cotton fiber anode outperforms the inconsecutive Si@Graphite anode in both cycling performance(capacity retention of 1777.15.mAh g^(-1) vs.682.5. mAh g^(-1) after 15. cycles at 0.3.C)and rate performance(12.4.2. mAh g^(-1) vs.3.0.2. mAh g^(-1) at 2.0 C).The findings of this study may open up new avenues for the development of globally interconnected conductive networks in Si-based anodes,thereby enabling the fabrication of high-performance LIBs.

关键词： 3. conductive network Biochar carbon-silicon anode Heteroatoms doping strategy DFT calculation Lithium-ion battery

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Evaluation of Sustainable Land Management and Diagnosis of Obstacle at County Scale in Sichuan Basin:Taking Lezhi County as Example

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 1046-1051页

作者： CHEN Guangjian 1, 2. 3., LIU Qing 1 1. chengdu institute of {2., Chinese Academy of Sciences, chengdu 610041, Sichuan,china 2. Graduate University of Chinese Academy of Sciences, Beijing 100049,{5. 3. Academy of Land Reconnaissance and Layout of Sichuan Province , chengdu 61003., Sichuan,{5. chengdu institute of {2. Chinese Academy of Sciences Chengdu Sichuan China Graduate University of Chinese Academy of Sciences Beijing China Academy of Land Reconnaissance and Layout of Sichuan Province Chengdu Sichuan China

This paper established sustainable land resources evaluating indicators fit for hilly area in Sichuan Basin, Southwest of china, and evaluated the case of sustainable land management of Lezhi County from 1990 to 2.01. The result showed that the land resource sustainable utilization ability in Lezhi County is belong to Second level （better sustainable）. Secondly, this paper diagnosed some years obstacles of sustainable land management of Lezhi County from base period to goal period and compared the obstacles factors in the indicators system. There were 16 indexes orderly become major affect factor to land sustainable utilization of Lezhi county in indicator system, of which there are 8 obstacles indexes exist both in 1990 and 2.01. The value of obstacles degree of five indicators exceeded {3.in 1990, but in 2.01, only two indicators＇ values were more than {3.

关键词： land resources sustainable land management assessment indicators diagnosis of obstacle

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Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 5. Years

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1,2.3., ZHOU Wancun 1 ,ZHOU Jieming 4 , ZHU Mingcang 3.5.1. institute of Mountain Hazards and Environment, Chinese Academy of Sciences ,{2., Sichuan, china 2. Graduate University of Chinese Academy of Sciences, Beijing 100049, china 3. Sichuan institute of Land Resource Management,{2., Sichuan , china 4. Department of Resources and Environment Science, Sichuan Normal University , chengdu 610061, Sichuan, china 5. College of Information Engineering, chengdu University of Technology, chengdu 61005., Sichuan, china institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China Graduate University of Chinese Academy of Sciences Beijing China Sichuan institute of Land Resource Management Chengdu Sichuan China Department of Resources and Environment Science Sichuan Normal University Chengdu Sichuan China College of Information Engineering Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography Information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1995.the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 5. years, but resumed in 2.02. the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.

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Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science china Earth Sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2.3. ZHANG Yili1, BAI Wanqi1, LIU Yanhua4, BAO Weikai5. LIU Linshan1, 2.& ZHENG Du1 1. {3. of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101,{2. 2. Graduate School of the Chinese Academy of Sciences, Beijing 10003.,{2. 3. College of Resources and Environment, Southwest Agricultural University, Chongqing 400716,{2. 4. The Ministry of Science and Technology, P. C.{2., Beijing 100862.{2. 5. chengdu institute of biology, Chinese Academy of Sciences, chengdu 610041,{2. institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Graduate School of the Chinese Academy of Sciences Beijing China College of Resources and Environment Southwest Agricultural University Chongqing China The Ministry of Science and Technology P. C. China Beijing China chengdu institute of {2. Chinese Academy of Sciences Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2.00 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2.00, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43.. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2.00, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

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Synthesis,crystal structure and thermal behavior of Rb(NTO)·H_2.

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Chinese Science Bulletin 2001年第1期46卷 45-49页

作者： HU Mancheng, GAO Shiyang, LIU Zhihong, SONG Jirong, XIA Shuping & YU Kaibei1. institute of Applied Chemistry, Shaanxi Normal University, Xi’an 710062. china 2. Department of Chemical Engineering, Northwest University, Xi’an 710069, china 3. chengdu Branch of Chinese Academy of Sciences, chengdu 610041, china institute of Applied Chemistry Shaanxi Normal University Xi’an China Department of Chemical Engineering Northwest University Xi’an China chengdu Branch of Chinese Academy of Sciences Chengdu China

The Rb(NTO) .H2. crystal has been synthesized by reaction of 3.nitro-l,2.4-triazole-5.one (NTO) with Rb2.O3.in aqueous solution. Its crystal structure has been determined. The crystal belongs to monoclinic system. Crystal structure data: space group P2./ n; a = 0.63. 0(1), b = 0.82. 1(2., c =1.2.6 4(3. nm; β = 97.90(1)°; V = 0.669 9 (2. nm3. Z = 4, Dc= 2.3.6 g/cm3.μ = 7.3.5.nm-1, F(000) = 448. An eight coordinated compound is formed between Rb+ with oxygen atoms and nitrogen atoms. A layer structure is formed by coordination bonds and hydrogen bonds. The thermal decomposition mechanism of this coordination compound is discussed.

关键词： Rb-NTO coordination compound crystal structrue thermal decomposition.

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Study on the coating of nano-scale SiO_2.film on the surface of nanocrystalline Mg-Al layered double hydroxides

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Science china Chemistry 2005年第2期48卷 107-114页

作者： ZHANG Zejiang1,2.3. MEI Xiujuan2. XU Chenghua1 & QIU Fali1 1. chengdu {3. of Organic Chemistry, Chinese Academy of Sciences,{2., china 2. Sichuan Fire Research {3. of Public Security Ministry, chengdu 61183., china 3. Graduate School of the Chinese Academy of Sciences, Beijing 10003., china Correspondence should be addressed to Zhang Zejiang (email: zzjzzjzz@***) chengdu institute of Organic Chemistry Chinese Academy of Sciences Chengdu China Sichuan Fire Research institute of Public Security Ministry Chengdu China Graduate School of the Chinese Academy of Sciences Beijing China

The coating process of a nano-scale SiO2.film on the nanocrystalline Mg-Al layered double hydroxides via a sol-gel process was investigated. The uniform and dense SiO2.ilm with a thickness of about 5.nm on the nano-LDHs particles was characterized by the solubility test in the dilute HNO3.or HCl acid, TEM and FT-IR, XRD, TG and DSC. The chemical shifts of binding en- ergies of Al 2., Mg 2., Si 2. and O 1s on the coated particles indicate that the coating of the SiO2.nano-film on the surface of the nano-LDHs proceeds through the formation of Mg-O-Si and Al-O-Si bonds. The thermal analysis shows that both the SiO2.coated nano-LDHs and the nano-LDHs have a similar mass loss process, in which there are three obvious stages of mass loss in the temperature range of 40—700℃. Furthermore, the more the coatedamount of SiO2.n the surface of the nano-LDHs is, the less the mass loss of the samples is at 700℃.The nano- LDHs have two obvious endothermic peaks at 2.4.67℃ and 43..13., whose corresponding heat absorption capacities are 412.2. J/g and 3.6.3. J/g, respectively. In contrast, the coated nano-LDHs have only one endothermic peak at 2.3.60℃ with a heat absorption capacity of 2.1.2.0}J/g.

关键词： layered double hydroxides, nanocrystalline, silica, coating.

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Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2. 3.,HUANG Zhiqin 2. 3. 4 1. The Faculty of Geography and Resources Science, Sichuan Normal University, chengdu 610066, Sichuan,{3. 2. {2. of Mountain Hazards and Environment, Chinese Academy of Sciences, chengdu 610041, Sichuan,{3. 3. Graduate University of the Chinese Academy of Sciences, Beijing 100049,{3. 4. Information Center of Land and Resources Department of Sichuan Province, chengdu 610041, Sichuan,{3. The Faculty of Geography and Resources Science Sichuan Normal University Chengdu Sichuan China institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China Graduate University of the Chinese Academy of Sciences Beijing China Information Center of Land and Resources Department of Sichuan Province Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992.is extracted from the dynamic polygons of 2.02. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 3.3.. The areas of steep land cultivated had been slowly reduced from 1992.to 2.02. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

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Impacts of permafrost changes on alpine ecosystem in Qinghai-Tibet Plateau

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Science china Earth Sciences 2006年第11期49卷 1156-1169页

作者： WANG Genxu1,3., LI Yuanshou2., WU Qingbai2.& WANG Yibo3.1. institute of Mountain Hazards and Environment, Chinese Academy of Sciences,{3.,{2. 2. Cold and Arid Regions Environmental and Engineering Research institute, Chinese Academy of Sciences, Lanzhou 73.000,{2. 3. Resource and Environment School, Lanzhou University, Lanzhou 73.000,{2. institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Resource and Environment School Lanzhou University Lanzhou China Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou China

Alpine cold ecosystem with permafrost environment is quite sensitive to climatic changes and the changes in permafrost can significantly affect the alpine ecosystem. The vegetation coverage, grassland biomass and soil nutrient and texture are selected to indicate the regime of alpine cold ecosystems in the Qinghai-Tibet Plateau. The interactions between alpine ecosystem and permafrost were investigated with the depth of active layer, permafrost thickness and mean annual ground temperature (MAGTs). Based on the statistics model of GPTR for MAGTs and annual air temperatures, an analysis method was developed to analyze the impacts of permafrost changes on the alpine ecosystems. Under the climate change and human engineering activities, the permafrost change and its impacts on alpine ecosystems in the permafrost region between the Kunlun Mountains and the Tanggula Range of Qinghai-Tibet Plateau are studied in this paper. The results showed that the per- mafrost changes have a different influence on different alpine ecosystems. With the increase in the thickness of active layer, the vegetation cover and biomass of the alpine cold meadow exhibit a significant conic reduction, the soil organic matter content of the alpine cold meadow ecosystem shows an exponential decrease, and the surface soil materials become coarse and gravelly. The alpine cold steppe ecosystem, however, seems to have a relatively weak relation to the permafrost environment. Those relationships resulted in the fact that the distribution area of alpine cold meadow decreased by 7.98% and alpine cold swamp decreased by 2..11% under the permafrost environment degradation during recent 15.years. In the future 5. years the alpine cold meadow ecosystems in different geomorphologic units may have different responses to the changes of the permafrost under different climate warming conditions, among them the alpine cold meadow and swamp ecosystem located in the low mountain and plateau area will have a relatively

关键词： permafrost environment, alpine cold ecosystem, statistics relationship, climate change, impacts, Qinghai-Tibet Plateau.

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CMC surfaces in the hyperbolic 3.space

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Chinese Science Bulletin 1998年第7期43卷 547-550页

作者： YU Zuhuan 1, 2.and LI Zhenqi 1, 3.1. institute of Mathematics, Fudan University, Shanghai 2.043.,{3. 2. Department of Mathematics,Sichuan Union University, {2. 610064,{3. 3. Department of Mathematics, Nanchang University, Nanchang 3. nstitute of Mathemalics Fudan University Shanghai China Department of Mathematics Sichuan Union University Chengdu China Department of Mathematics Nanchang University Nanchang China

CMC-H surfaces satisfying H≥1 are studied. It is proved that these surfaces possess a natural representation which is a generalization of the Bryant’s result.

关键词： hyperbolic space CMC surface Weierstrass representation.

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Impact of land-use change on hydrological processes in the Maying River basin, china

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Science china Earth Sciences 2006年第10期49卷 1098-1110页

作者： WANG Genxu1,3. ZHANG Yu2. LIU Guimin2.& CHEN Lin3.1. institute of Mountain Hazards and Environment, Chinese Academy of Sciences,{3.,{2. 2. Cold and Arid Regions Environmental and Engineering Research institute, Chinese Academy of Sciences, Lanzhou 73.000,{2. 3. Resource and Environment School, Lanzhou University, Lanzhou 73.000,{2. institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Resource and Environment School Lanzhou University Lanzhou China Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou China

Since the 1960s, dramatic changes have taken place in land-use patterns characterized by the persistent expansion of cultivated land and a continuous decrease in natural woodland and grassland in the arid inland river basins of china. It is very important to assess the effects of such land-use changes on the hydrological processes so vital for water resource management and sustainable development on the catchment scale. The Maying River catchment, a typical arid inland watershed located in the middle of the Hexi Corridor in northwest china, was the site chosen to investigate the hydrological responses to land-use changes. The annual runoff, base flow, maximum peak flow, and typical seasonal runoff in both spring and autumn flood periods were selected as the variables in the hydrological processes. Statistical-trend analysis and curvilinear regression were utilized to detect the trends in hydrological variables while eliminating the climatic influence. The relationship between cultivated land-use and hydrological variables was analyzed based on four periods of land-use variation data collected since 196{2. A runoff model was established composed of two factors, i.e., cultivated land use and precipitation. The impact of land use changes, especially in the large ar- eas of upstream woodland and grassland turned into cultivated lands since 1967, has resulted in a mean annual runoff decrease of 2..12., a base flow decline of 3.2.3.2}, a drop in the maximum peak discharge of 3.2.77%, and mean discharge decreases in spring and autumn of 3..0{2. and 2..87% respectively, of which the contribution of cultivated land expansion to the influence of annual runoff amounts to 77%-80%, with the contribution to the influence of spring discharge being 73.-81%, and that to the influence of base flow reaching 62.-6{2.. Thus, a rational regulation policy of land use patterns is vitally important to the sustainable use of water resources and the proper development of the entire catchment.

关键词： land-use change, arid inland river catchment, hydrological process, impact, Maying River.

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