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| 1 | Soil Erosion and Vegetation Succession in Alpine Kobresia Steppe Meadow Caused by Plateau Pika——A Case Study of Nagqu County, Tibet显示文摘This paper evaluated the impacts of mounds created by the plateau pika (Ochotona curzoniae) on the vege- tation composition, structure, and species diversity of an alpine Kobresia steppe meadow in Nagqu County, Tibet Autonomous Region, China. Based on mound height or the depth of erosion pit, we defined five stages of erosion and compared the floristic features of communities at these stages with those in undisturbed sites. In the study area, the mounds and pits covered up to 7% of the total area. Lancea tibetica, Lamiophlomis rotata, and Potentilla bifurca were the dominant species in erosion pits, and Kobresia pygmaea, the dominant species in undisturbed sites, became a com- panion species in eroded areas. In the process of erosion, the original vegetation was covered by soil ejected by the pika, then the mounds were gradually eroded by wind and rain, and finally erosion pits formed. The vegetation coverage in- creased with increasing erosion stages but remained significantly lower than that in undisturbed sites. Improved coverage eventually reduced soil erosion, and pit depth eventually stabilized at around 20cm. Aboveground biomass increased with increasing erosion stage, but the proportion of low-quality forage reached more than 94%. The richness index and Shannon-Wiener index increased significantly with increasing erosion stage, but the richness index in mound and pit areas was significantly lower than that in undisturbed sites. | WEI Xinghu LI Sen Yang Ping Cheng Huaishun | 2007 | Chinese Geographical Science2007,17,1: | 22 |
| 2 | Layer-by-layer deposition of bioactive layers on magnesium alloy stent materials to improve corrosion resistance and biocompatibility显示文摘Magnesium alloy is considered as one of the ideal cardiovascular stent materials owing to its good mechanical properties and biodegradability.However,the in vivo rapid degradation rate and the insufficient biocompatibility restrict its clinical applications.In this study,the magnesium alloy(AZ31B)was modified by combining the surface chemical treatment and in-situ self-assembly of 16-phosphonyl-hexadecanoic acid,followed by the immobilization of chitosan-functionalized graphene oxide(GOCS).Heparin(Hep)and GOCS were alternatively immobilized on the GOCS-modified surface through layer by layer(LBL)to construct the GOCS/Hep bioactive multilayer coating,and the corrosion resistance and biocompatibility were extensively explored.The results showed that the GOCS/Hep bioactive multilayer coating can endow magnesium alloys with an excellent in vitro corrosion resistance.The GOCS/Hep multilayer coating can significantly reduce the hemolysis rate and the platelet adhesion and activation,resulting in an excellent blood compatibility.In addition,the multilayer coating can not only enhance the adhesion and proliferation of the endothelial cells,but also promote the vascular endothelial growth factor(VEGF)and nitric oxide(NO)expression of the attached endothelial cells on the surfaces.Therefore,the method of the present study can be used to simultaneously control the corrosion resistance and improve the biocompatibility of the magnesium alloys,which is expected to promote the application of magnesium alloys in biomaterials or medical devices,especially cardiovascular stent. | Fan Gao Youdong Hu Guicai Li Sen Liu Li Quan Zhongmei Yang Yanchun Wei Changjiang Pan | 2020 | Bioactive Materials2020,5,3: | 12 |
| 3 | Genetic alterations and expression of inhibitor of growth 1 in human sporadic colorectal cancer显示文摘AIM: To explore the effect and significance of inhibitor of growth 1 (ING1) gene in carcinogenesis and progression of human sporadic colorectal cancer.METHODS: mRNA expression, mutation, and loss of heterozygosity (LOH) of ING1 gene in 35 specimens of sporadic colorectal cancer tissues and the matched normal mucous membrane tissues were detected by semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR),PCR-single strain conformation polymorphism (PCR-SSCP)and PCR-simple sequence length polymorphism (PCR-SSLP)using microsatellite markers, respectively.RESULTS: The average ratios of light intensities of p33ING1b and p47ING1a mRNA expression in the cancerous tissues were significantly lower than those in normal tissues.The difference between the two mRNA splices was not significant in the matched tissues. In addition, the ratios of light intensities of p33INB1b and p47ING1a mRNA expression in the cancerous tissues of Dukes' stages C and D were significantly lower than those in cancerous tissues of Dukes'stages A and B. However, no mutation of ING1 gene was detected in all 35 cases; only 4 cases of LOH (11.4%)were found.CONCLUSION: p33ING1b and p47ING1a mRNA expressions are closely related with the carcinogenesis and progression of human sporadic colorectal cancer. No mutation of ING1gene is found, and there are only few LOH in sporadic colorectal cancers. These might not be the main reasons for the down regulation of ING1 expression. Its low expression may happen in transcription or post-transcription. | Li-Sheng Chen Jian-Bao Wei Yong-Chun Zhou Sen Zhang Jun-Lin Liang Yun-Fei Cao Zong-Jiang Tang Xiao-Long Zhang Feng Gao | 2005 | World Journal of Gastroenterology2005,11,39: | 12 |
| 4 | A wind tunnel simulation of the dynamic processes involved in sand dune formation on the western coast of Hainan Island显示文摘海南岛的西方的海岸展出一处无树平原风景。沙丘的许多类型包括横向的沙丘山脉,纵向沙丘隆起,椭圆的沙丘,小灌木林沙丘,;爬的沙丘,广泛地在沿海的地区被散布。在冬季,高周波;高精力的 NE 风(主导的风) 是流行的,与 S35.6 ° W 的一个结果的飘移方向(RDD ) 。在春天,低频率;低精力的 SW 第二等的风占优势,与 N25.1 ° E 的 RDD。风洞模拟表明在沙丘表面上的气流是控制侵蚀的主要因素;沙丘表面的免职模式;沙丘的词法发展。在这个区域的双向风环境,与二个季节结盟不同能级,在椭圆的沙丘的表面上的气流,酒吧禅宗沙丘,;横向的沙丘山脉将展出一个横向的模式,而在纵向沙丘山脉上的气流展出一个侧面的模式;那在爬沙丘上展出一个爬环流的模式。这些模式代表不同动态过程。海南岛的西方的海岸上的沿海的沙丘被象向岸风那样的因素影响,沙来源,沿海的斜坡,河,;森林护田林带。特别地补充这些沙丘的沙的来源影响发展模式:当有更多的沙时,模式显示出在沙丘山脉之间的积极平衡免职;沙丘;否则,它显示出否定平衡免职。森林护田林带的存在或缺席也影响免职;沙丘发展模式;沙丘形式的转变。沿海的沙丘;内陆沙漠沙丘经历类似的动态过程,而是前者有更多样化的形状;更复杂的形成机制。 | LI Sen LIU Xianwan LI Huichuan ZHENG Yinghua WEI Xinghu | 2007 | Journal of Geographical Sciences2007,17,4: | 9 |
| 5 | Strategies for improving the storage performance of silicon-based anodes in lithium-ion batteries显示文摘Silicon has attracted much attention as a promising anode material for lithium-ion batteries (LIBs) due to its high theoretical capacity and rich resource abundance. However, the practical battery use of Si is challenged by its low conductivity and drastic volume variation during the Li uptake/release process. Tremendous efforts have been made on shrinking the particle size of Si into nanoscale so that the volume variation could be accommodated. However, the bare nano-Si material would still pulverize upon (de)lithiation. Moreover, it shows an excessive surface area to invite unlimited growth of solid electrolyte interface that hinders the transportation of charge carriers, and an increased interparticle resistance. As a result, the Si nanoparticles gradually lose their electrical contact during the cycling process, which accounts for poor thermodynamic stability and sluggish kinetics of the anode reaction versus Li. To address these problems and improve the Li storage performance of nano-Si anode, proper structural design should be applied on the Si anode. In this perspective, we will briefly review some strategies for improving the electrochemistry versus Li of nano-Si materials and their derivatives, and show opinions on the optimal design of nanostructured Si anode for advanced LIBs. | Wei Tao Ping Wang Ya You Kyusung Park Cao-Yu Wang Yong-Ke Li Fei-Fei Cao Sen Xin | 2019 | Nano Research2019,12,8: | 9 |
| 6 | NanoSIMS analytical technique and its applications in earth sciences显示文摘Despite the significant improvement on spatial resolution,Nano SIMS still preserves relatively high mass resolution,sensitivity,and analytical precision.It has become an important analytical platform to determine chemical compositions of solid materials,and has been widely used in space,earth,life,and materials sciences,etc.By using a Cs+ion beam with a size as small as 50nm scanning over sample surfaces,we are able to obtain high spatial resolution images of up to 7 species simultaneously.When utilizing Faraday cup,high analytical precision of 0.3‰–0.5‰(1SD)for C,O and S isotopic analysis can be achieved.Although this precision level is still lower than that of conventional SIMS,it already meets the major requirements of Earth Sciences.In 2011,the first Nano SIMS of China(Cameca Nano SIMS 50L)was installed at Institute of Geology and Geophysics,Chinese Academy of Sciences.Based on the working mechanism and analytical modes of the instrument,this paper will systematically introduce the analytical methods established with the Nano SIMS and their potential applications in earth sciences.These methods include trace element distribution images in mineral zoning,high spatial resolution(2–5?m)Pb-Pb and U-Pb dating,water content and H isotopic analysis for silicate glass and apatite,C isotopic analysis for diamond and graphite,O isotopic analysis for carbonate,S isotopic analysis for sulfides.In addition,the specific requirements for sample preparation will also be introduced in order to facilitate domestic earth scientists’use. | YANG Wei HU Sen ZHANG JianChao HAO JiaLong LIN YangTing | 2015 | Science China Earth Sciences2015,58,10: | 9 |
| 7 | Oxygen-deficient metal oxides:Synthesis routes and applications in energy and environment显示文摘Oxyge n vaca ncies impla ntation is an efficie nt way to adjust the physical and chemical properties of metal oxide nano materials to meet the requirements for particular applications.Through reasonable defects design,oxyge-deficient metal oxides with excellent optical and electrical properties are widely applied for environmental protection and energy uses.This review discusses recent advances in synthetic approaches of oxygervdeficient metal oxides and their applications in photocatalysis,electrocatalysis,and energy storage devices.The perspectives of oxyge n?deficie nt metal oxides for increased en ergy dema nd and en vironme ntal sustai liability are also exami ned. | Di Zu Haiyang Wang Sen Lin Gang Ou Hehe Wei Shuqing Sun Hui Wu | 2019 | Nano Research2019,12,9: | 9 |
| 8 | Olivine-norite rock detected by the lunar rover Yutu-2 likely crystallized from the SPA-impact melt pool显示文摘Chang’E-4 landed in the South Pole-Aitken(SPA)basin,providing a unique chance to probe the composition of the lunar interior.Its landing site is located on ejecta strips in Von Karm´an crater that´possibly originate from the neighboring Finsen crater.A surface rock and the lunar regolith at 10 sites along the rover Yutu-2 track were measured by the onboard Visible and Near-Infrared Imaging Spectrometer in the first three lunar days of mission operations.In situ spectra of the regolith have peak band positions at 1 and 2μm,similar to the spectral data of Finsen ejecta from the Moon Mineralogy Mapper,which confirms that the regolith’s composition of the landing area is mostly similar to that of Finsen ejecta.The rock spectrum shows similar band peak positions,but stronger absorptions,suggesting relatively fresh exposure.The rock may consist of 38.1±5.4%low-Ca pyroxene,13.9±5.1%olivine and 48.0±3.1%plagioclase,referred to as olivine-norite.The plagioclase-abundant and olivine-poor modal composition of the rock is inconsistent with the origin of the mantle,but representative of the lunar lower crust.Alternatively,the rock crystallized from the impact-derived melt pool formed by the SPA-impact event via mixing the lunar crust and mantle materials.This scenario is consistent with fast-cooling thermal conditions of a shallow melt pool,indicated by the fine to medium-sized texture(<3 mm)of the rock and the SPA-impact melting model[Icarus 2012;220:730–43]. | Honglei Lin Zhiping He Wei Yang Yangting Lin Rui Xu Chi Zhang Meng-Hua Zhu Rui Chang Jinhai Zhang Chunlai Li Hongyu Lin Yang Liu Sheng Gou Yong Wei Sen Hu Changbin Xue Jianfeng Yang Jie Zhong Xiaohui Fu Weixing Wan Yongliao Zou | 2020 | National Science Review2020,7,5: | 9 |
| 9 | Effects of riparian land use on water quality and fish communities in the headwater stream of the Taizi River in China显示文摘 | Sen DING Yuan ZHANG Bin LIU Weijing KONG Wei MENG | 2013 | Frontiers of Environmental Science & Engineering2013,7,5: | 8 |
| 10 | Association of Overlapped and Un-overlapped Comorbidities with COVID-19 Severity and Treatment Outcomes: A Retrospective Cohort Study from Nine Provinces in China显示文摘Objective Several COVID-19 patients have overlapping comorbidities. The independent role of each component contributing to the risk of COVID-19 is unknown, and how some non-cardiometabolic comorbidities affect the risk of COVID-19 remains unclear.Methods A retrospective follow-up design was adopted. A total of 1,160 laboratory-confirmed patients were enrolled from nine provinces in China. Data on comorbidities were obtained from the patients’ medical records. Multivariable logistic regression models were used to estimate the odds ratio(OR) and 95% confidence interval(95% CI) of the associations between comorbidities(cardiometabolic or non-cardiometabolic diseases), clinical severity, and treatment outcomes of COVID-19.Results Overall, 158(13.6%) patients were diagnosed with severe illness and 32(2.7%) had unfavorable outcomes. Hypertension(2.87, 1.30–6.32), type 2 diabetes(T2 DM)(3.57, 2.32–5.49),cardiovascular disease(CVD)(3.78, 1.81–7.89), fatty liver disease(7.53, 1.96–28.96), hyperlipidemia(2.15, 1.26–3.67), other lung diseases(6.00, 3.01–11.96), and electrolyte imbalance(10.40, 3.00–26.10)were independently linked to increased odds of being severely ill. T2 DM(6.07, 2.89–12.75), CVD(8.47,6.03–11.89), and electrolyte imbalance(19.44, 11.47–32.96) were also strong predictors of unfavorable outcomes. Women with comorbidities were more likely to have severe disease on admission(5.46,3.25–9.19), while men with comorbidities were more likely to have unfavorable treatment outcomes(6.58, 1.46–29.64) within two weeks.Conclusion Besides hypertension, diabetes, and CVD, fatty liver disease, hyperlipidemia, other lung diseases, and electrolyte imbalance were independent risk factors for COVID-19 severity and poor treatment outcome. Women with comorbidities were more likely to have severe disease, while men with comorbidities were more likely to have unfavorable treatment outcomes. | MA Yan ZHU Dong Shan CHEN Ren Bo SHI Nan Nan LIU Si Hong FAN Yi Pin WU Gui Hui YANG Pu Ye BAI Jiang Feng CHEN Hong CHEN Li Ying FENG Qiao GUO Tuan Mao HOU Yong HU Gui Fen HU Xiao Mei HU Yun Hong HUANG Jin HUANG Qiu Hua HUANG Shao Zhen JI Liang JIN Hai Hao LEI Xiao LI Chun Yan LI Min Qing LI Qun Tang LI Xian Yong LIU Hong De LIU Jin Ping LIU Zhang MA Yu Ting MAO Ya MO Liu Fen NA Hui WANG Jing Wei SONG Fang Li SUN Sheng WANG Dong Ting WANG Ming Xuan WANG Xiao Yan WANG Yin Zhen WANG Yu Dong WU Wei WU Lan Ping XIAO Yan Hua XIE Hai Jun XU Hong Ming XU Shou Fang XUE Rui Xia YANG Chun YANG Kai Jun YUAN Sheng Li ZHANG Gong Qi ZHANG Jin Bo ZHANG Lin Song ZHAO Shu Sen ZHAO Wan Ying ZHENG Kai ZHOU Ying Chun ZHU Jun Teng ZHU Tian Qing ZHANG Hua Min WANG Yan Ping WANG Yong Yan 无 | 2020 | Biomedical and Environmental Sciences2020,33,12: | 8 |
| 11 | Active source monitoring at the Wenchuan fault zone:coseismic velocity change associated with aftershock event and its implication显示文摘With the improvement of seismic observation system, more and more observations indicate that earthquakes may cause seismic velocity change. However, the amplitude and spatial distribution of the velocity variation remains a controversial issue. Recent active source monitoring carried out adjacent to Wenchuan Fault Scientific Drilling(WFSD) revealed unambiguous coseismic velocity change associated with a local Ms5.5 earthquake. Here, we carry out forward modeling using two-dimensional spectral element method to further investigate the amplitude and spatial distribution of observed velocity change. The model is well constrained by results from seismic reflection and WFSD coring. Our model strongly suggests that the observed coseismic velocity change is localized within the fault zone with width of *120 m rather than dynamic strong ground shaking. And a velocity decrease of *2.0 %within the fault zone is required to fit the observed travel time delay distribution, which coincides with rock mechanical experiment and theoretical modeling. | Wei Yang Hongkui Ge Baoshan Wang Jiupeng Hu Songyong Yuan Sen Qiao | 2014 | Earthquake Science2014,27,6: | 6 |
| 12 | Improving the electrical performance of resistive switching memory using doping technology显示文摘In this paper, improvements of resistive random access memory (RRAM) using doping technology are summarized and analyzed. Based on a Cu/ZrO2/Pt device, three doping technologies with Ti ions, Cu, and Cu nanocrystal, respectively, are adopted in the experiments. Compared to an undoped device, improvements focus on four points: eliminating the electroforming process, reducing operation voltage, improving electrical uniformity, and increasing device yield. In addition, thermal stability of the high resistance state and better retention are also achieved by the doping technology. We demonstrate that doping technology is an effective way of improving the electrical performance of RRAM. | WANG Yan LIU Oi LU HangBing LONG ShiBing WANG Wei LI YingTao ZHANG Sen LIAN WenTai YANG JianHong LIU Ming | 2012 | Chinese Science Bulletin2012,57,11: | 6 |
| 13 | Different BAG-1 isoforms have distinct functions in modulating chemotherapeutic-induced apoptosis in breast cancer cells显示文摘 | Hong-yu LIU Zhuo-min WANG Yun BAI Min WANG Ying LI Sen WEI Qing-hua ZHOU Jun CHEN | 2009 | Acta Pharmacologica Sinica2009,30,2: | 5 |
| 14 | Simultaneous determination of brominated phenols in soils显示文摘Brominated phenols(BPs),a widely used group of emerging flame retardants,are important environmental contaminants and exhibit endocrine disrupting potential.Method for simultaneous determination of tetrabromobisphenol A(TBBPA),tribromophenol(TBP),dibromophenols(DBPs)and monobromophenols(MBPs)in soils using gas chromatography-mass spectrometry analysis(GC/MS)was successfully developed.Cleanup methods for soil extracts including several solid-phase extraction cartridges and diferent elution solvents were compared and optimized.Florisil cartridge with dichloromethane as the elution reagent was selected for sample cleanup owing to its high and reproducible recoveries of the target analytes in soils.Derivatization conditions were tested and the optimal conditions were obtained with 20μL silylation reagent at room temperature.The chromatographic separation was optimized with diferent columns and DB-XLB column was selected for its excellent separation of the analytes.The limits of detection for the target compounds were from 0.04 to 0.19 ng/g.Mean recoveries of the compounds from spiked soils exceeded 84%with a good reproducibility,excepting that the recovery of 2-bromophenol was relatively poor(lower than 55%)due to its instability.The developed method was applied to the determination of the BPs in the soils collected from e-waste sites.The contents of BPs in the soils were at ng/g levels with TBBPA and TBP the most frequently detected.To our knowledge,this is the first report for the simultaneous determination of TBBPA,TBP,DBPs and MBPs in soils. | Wei Han Sen Wang Honglin Huang Lei Luo Shuzhen Zhang | 2013 | Journal of Environmental Sciences2013,25,11: | 5 |
| 15 | Deposition of sandstorms in a vegetation-covered sand dune in Ejin Oasis and its characteristics显示文摘“Ejin Section” found in a typical vegetation-covered sand dune in Ejin Oasis was investigated. In this study, 263 samples were taken from the section for grain-size analysis, 25 for chemical analysis, 11 for 14C dating and 6 for scanning electron microscope (SEM). The results of the study indicate that 3 types of the sediments in the section can be identified, YS, LS and ST. YS, homogeneous yellow-brown dune sands, is equal to those of inland deserts, LS, loess-like sandy soils, is the same as the sandy loess in the middle Yellow River and modern falling dusts, and ST, sandy sediments interbeded with the deadwood and defoliation of Tamarix spp, represents the depositional process of the section interrupted by abrupt changes in climate. The Ejin Section has recorded the repeated dust-storms or sandstorms since 2500 yr BP and the peak periods of the dust-storms or sandstorms revealed by the section are consistent with the records of “dust rains” in historical literatures, indicating that the change of climate is a key factor to increase sandstorms or dust-storms, whereas, “artificial” factor may only be an accelerating one for desertification. | WENXiaohao LI Baosheng WANG Wei LI Sen OU Xianjiao ZHENG Yanming | 2006 | Journal of Geographical Sciences2006,16,4: | 3 |
| 16 | First genetic assessment of brackish water polychaete Tylorrhynchus heterochaetus: mitochondrial CO/sequences reveal strong genetic differentiation and population expansion in samples collected from southeast China and north Vietnam显示文摘Tylorrhynchus heterochaetus is a widespread benthic polychaete worm found in coastal brackish waters of the west Pacific.It has high ecological and economic value as a biomarker of water quality and as a high-quality feed in aquaculture and fisheries and is considered a delicacy in some areas of Asia.However,it has experienced a marked reduction in recent years due to overexploitation as well as changes in the environment and climate.Here,to comprehensively understand its genetic background and thus provide insights for better conservation and utilization of this species,we assessed the genetic variability and demographic history of T.heterochaetus individuals sampled from eight locations along the coasts of southeast China and north Vietnam based on mitochondrial cytochrome c oxidase I(COI)sequences.We observed high haplotype diversity(Hd),with an average of 0.926,but relatively low nucleotide diversity(π),with a mean of 0.032 across all samples.A total of 94 polymorphic sites and 85 haplotypes were identified among 320 individuals.The pairwise genetic distances among haplotypes ranged from 0.001 to 0.067,with the high intraspecific divergence possibly reflecting geographic isolation and gene pool fragmentation.Significant genetic structures were revealed among the studied locations;specifically,the eight locations could be treated as six genetically different populations based on pairwiseΦST results(0.026–0.951,P<0.01).A significant pattern of isolation-by-distance was detected between the genetic and geographic distances(r=0.873,P=0.001).Three geographic lineages were defined based on phylogenetic tree and network analyses of COI haplotypes.AMOVA results indicated that genetic variations mainly occurred among the three lineages(89.96%).Tests of neutrality and mismatch distribution suggested that T.heterochaetus underwent recent population expansion.These results provide the first report on the genetic status of T.heterochaetus and will be valuable for the management of genetic resources and better understanding of the ecology and evolution in this species. | Xing-Han Chen Sen Yang Wei Yang Yuan-Yuan Si Rui-Wen Xu Bin Fan Le Wang Zi-Ning Meng | 2020 | Zoological Research2020,41,1: | 3 |
| 17 | Changes in plant species composition and diversity of alpine Kobresia (Kobresia pygmaea) steppe meadow at different stages of desertification in the North Tibetan plateau显示文摘The impacts of desertification on the vegetation composition, structure, and species diversity of alpine Kobresia steppe meadow were evaluated in an area of severe desertification in Anduo County, Tibet Autonomous Region, northern China. We investigated and analyzed the floristic features of communities at four different stages of desertification (slight desertification [SLD], moderate desertification [MD], severe desertification [SD], and very severe desertification [VSD]). The composition and structure of the alpine Kobresia steppe meadow at the SLD site differed significantly from that at the MD, SD, and VSD sites. Species that were more drought resistant and inedible by livestock were the dominant species at the SD site. No plants were found in the shifting dunes of the VSD site. Species diversity also decreased with increasing desertification. The SLD site had the largest mean number of species and individuals and the largest richness index; the MD grassland had the largest Shannon-Wiener index and evenness index, but the smallest Simpson's index. The vegetation cover declined from 91.8% to 34.8% as desertification increased from SLD to SD, and reached 0% in VSD areas with shifting dunes. | XingHu Wei 1*, Ping Yang 2, Sen Li 1, YuXiang Dong 3, ChunLai Zhang 41. Department of Resources and Environmental of Foshan University, Foshan, Guangdong 528000, China.2. Resources and Environmental Bureau , Chinese Academy of Science, Lanzhou, Gansu 730000, China. 3. Department of Geography of Zhongshan University, Guangzhou, Guangdong 510275, China. 4. Beijing Normal University, Beijing 100875, China. | 2009 | Research in Cold and Arid Regions2009,1,1: | 3 |
| 18 | The causes and processes responsible for rocky desertification in karst areas of southern China显示文摘The karst region of southern China is a fragile ecological zone with widespread rocky desertification. This paper describes the rocky desertification occurring in this region in terms of both natural and anthropogenic factors. During geological time periods, the region's changing environment governed the natural rocky desertification processes, whereas during historical and modern times, anthropogenic processes have been superimposed on these natural processes. Human activities have accelerated and exacerbated rocky desertification. The period from the beginning to the middle of the Qing dynasty was an important transitional period in which human activities began to exert a particularly strong influence on rocky desertification. Since then, the effect of anthropogenic factors has increasingly exceeded the effect of natural factors. The rocky desertification process in southern China's karst region combines surface ecological processes (including vegetation degradation and loss, soil erosion, surface water loss, and bedrock solution) with a reduction of the land's biological productivity, leading to degradation that produces rocky desert. Controlling rocky desertification requires comprehensive development of sustainable agriculture and economic development that provides employment alternatives to agriculture and thereby promotes the rehabilitation of rocky desertified land. | Sen Li 1,2*, XingHu Wei 1, JinGuo Huang 1, XiZhi Wang 1, GuanYao Lu 1, HuiXia Li 11. Institute of Resources and Environment Science, Foshan University, Foshan, Guangdong 528000, China.2. College of Geography and Environment Science, Northwest Normal University, Lanzhou, Gansu 730070, China. | 2009 | Research in Cold and Arid Regions2009,1,1: | 3 |
| 19 | Improving phase transition temperature of VO_(2) via Ge doping:a combined experimental and theoretical study显示文摘Enhancing the semiconductor-metal phase transition temperature(TSMT)of VO_(2) is of great consequence for further exploring the potential applications of VO_(2) at elevated temperatures.In this study,Ge^(4+)-doped VO_(2)(Ge_(x)V_(1-x)O_(2))samples were prepared by the hydrothermal and annealing approach.X-ray diffraction(XRD),high-resolution transmission electron microscopy(HRTEM),differential scanning calorimetry(DSC)and resistivity-temperature(R-T)analyses were used to investigate the influence of Ge doping on the lattice structures and phase transition properties of Ge_(x)V_(1-x)O_(2) samples.We found that the lattice parameter of Ge_(x)V_(1-x)O_(2) decreased with the Ge concentration increasing from 2 at%to 18 at%,which was further supported by density functional theory(DFT)-based first-principle simulations.TSMT firstly increased from 64.5 to 73.0℃ at 8 at% Ge and then decreased to 71.5℃ at higher Ge concentration.Furthermore,DFT analysis revealed that the impact of lattice distortion induced by Ge doping rather than the changes in electronic structure is more pronounced on modulating TSMT of Ge_(x)V_(1-x)O_(2).The present work has pointed out the direction that the TSMT could be enhanced and illustrated the physical reason behind the regulation of TSMT in ionsdoped VO_(2) systems. | Lin Wang Yu-Qi Hao Wei Ma Sen Liang | 2021 | Rare Metals2021,40,5: | 3 |
| 20 | Fabrication of LSGM thin films on porous anode supports by slurry spin coating for IT-SOFC显示文摘La_(0.9)Sr_(0.1)Ga_(0.8)Mg_(0.2)O_(3-δ)(LSGM) and La_(0.7)Sr_(0.3)Cr_(0.5)Mn_(0.5)O_(3-δ)(LSCM) powders were synthesized by glycine-nitrate process, and LSGM electrolyte thin film was successfully fabricated on porous anode substrate of LSCM by slurry spin coating technology. Some technical parameters for the preparation of LSGM thin films were systematically investigated, including ink composition,sintering temperature, and spin coating times. The electrolyte films with the best compactness and somewhat rough are obtained when the operating parameters are fixed as follows: the content of ethyl cellulose as binder is 5 wt%, the content of terpineol as modifier is 5 wt%, the optimum coating cycle number is 9 times, and the best post-deposition sintering temperature is 1,400 °C for 4 h. | Hong-Yan Sun Wei Sen Wen-Hui Ma Jie Yu Jian-Jun Yang | 2015 | Rare Metals2015,34,11: | 3 |