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132篇 您的检索式:作者名="WANG ShuFang"
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1Quantitative characterization of reservoir space in the Lower Silurian Longmaxi Shale,southern Sichuan,China显示文摘Based on the drilling data of the Upper Ordovician Wufeng Shale and the Lower Silurian Longmaxi Shale in southern Sichuan Basin,the construction of matrix pores and the development condition of fractures in a marine organic-rich shale are quantitatively evaluated through the establishment of the reservoir petrophysical models and porosity mathematical models.Our studies show that there are four major characteristics of the Longmaxi Shale confirmed by the quantitative characterization:(1)the pore volume of per unit mass is the highest in organic matter,followed in clay minerals,finally in brittle minerals;(2)the porosity of the effective shale reservoir is moderate and equal to that of the Barnett Shale,and the main parts of the shale reservoir spaces are interlayer pores of clay minerals and organic pores;(3)the porosity of the organic-rich shale is closely related to TOC and brittle mineral/clay mineral ratio,and mainly increases with TOC and clay mineral content;(4)fractures are developed in this black shale,and are mainly micro ones and medium-large ones.In the Longmaxi Shale,the fracture density increases from top to bottom,reflecting the characteristics with high brittle mineral content,high Young’s modulus,low Poisson's ratio and high brittleness at its bottom.WANG YuMan DONG DaZhong YANG Hua HE Ling WANG ShiQian HUANG JinLiang PU BoLing WANG ShuFang 2014Science China Earth Sciences2014,57,2:36
2Progress in China's Unconventional Oil & Gas Exploration and Development and Theoretical Technologies显示文摘The new century has witnessed a strategic breakthrough in unconventional oil & gas.Hydrocarbon accumulated in micro-/nano-scale pore throat shale systems has become an important domain that could replace current oil & gas resources.Unconventional oil & gas plays an increasingly important role in our energy demand.Tight gas,CBM,heavy oil and asphaltic sand have served as a key domain of exploration & development,with tight oil becoming a 'bright spot' domain and shale gas becoming a 'hotspot' domain.China has made great breakthroughs in unconventional oil & gas resources,such as tight gas,shale gas,tight oil and CBM,and great progress in oil shale,gas hydrate,heavy oil and oil sand.China has an estimated(223-263)×10~8t of unconventional oil resources and(890-1260)×l0^(12)m^3 of gas resources.China has made a breakthrough for progress in unconventional oil & gas study.New progress achieved in fine-grained sedimentary studies related to continental open lacustrine basin large-scale shallow-water delta sand bodies,lacustrine basin central sandy clastic flow sediments and marine-continental fine-grained sediments provide a theoretical basis for the formation and distribution of basin central reservoir bodies.Great breakthroughs have been made in unconventional reservoir geology in respect of research methodology & technology,multi-scale data merging and physical simulation of formation conditions.Overall characterization of unconventional reservoirs via multi-method and multi-scale becomes increasingly popular and facilitates the rapid development of unconventional oil & gas geological theory,method and technology.The formation of innovative,continuous hydrocarbon accumulation theory,the establishment of the framework of the unconventional oil & gas geological theory system,and the determination of the implications,geological feature,formation mechanism,distribution rule and core technology of unconventional oil& gas geological study lays a theoretical foundation for extensive unconventional oil & gas exploration and development.Theories and technologies of unconventional oil & gas exploration and development developed rapidly,including some key evaluation techniques such as 'sweet spot zone' integrated evaluation and a six-property evaluation technique that uses hydrocarbon source,lithology,physical property,brittleness,hydrocarbon potential and stress anisotropy,and some key development &engineering technologies including micro-seismic monitoring,horizontal drilling & completion and 'factory-like' operation pattern, 'man-made reservoir' development,which have facilitated the innovative development of unconventional oil & gas.These breakthroughs define a new understanding in four aspects:①theoretical innovation;② key technologies;③ complete market mechanism and national policy support;and ④ well-developed ground infrastructure,which are significant for prolonging the life cycle of petroleum industry,accelerating the upgrade and development of theories and technologies and altering the global traditional energy structure.ZOU Caineng YANG Zhi ZHU Rukai ZHANG Guosheng HOU Lianhua WU Songtao TAO Shizhen YUAN Xuanjun DONG Dazhong WANG Yuman WANG Lan HUANG Jinliang WANG Shufang 2015Acta Geologica Sinica(English Edition)2015,89,3:27
3Effects of land use, climate, topography and soil properties on regional soil organic carbon and total nitrogen in the Upstream Watershed of Miyun Reservoir, North China显示文摘Soil organic carbon (SOC) and total nitrogen (TN) contents as well as their relationships with site characteristics are of profound importance in assessing current regional, continental and global soil C and N stocks and potentials for C sequestration and N conservation to offset anthropogenic emissions of greenhouse gases. This study investigated contents and distribution of SOC and TN under different land uses, and the quantitative relationships between SOC or TN and site characteristics in the Upstream Watershed of Miyun Reservoir, North China. Overall, both SOC and TN contents in natural secondary forests and grasslands were much higher than in plantations and croplands. Land use alone explained 37.2% and 38.4% of variations in SOC and TN contents, respectively. The optimal models for SOC and TN, achieved by multiple regression analysis combined with principal component analysis (PCA) to remove the multicollinearity among site variables, showed that elevation, slope, soil clay and water contents were the most significant factors controlling SOC and TN contents, jointly explaining 70.3% of SOC and 67.1% of TN contents variability. Only does additional 1.9% and 3% increase in the interpretations of SOC and TN contents variability respectively when land use was added to regressions, probably due to environment factors determine land use. Therefore, environmental variables were more important for SOC and TN variability than land use in the study area, and should be taken into consideration in properly evaluating effects of future land use changes on SOC and TN on a regional scale.Shufang Wang Xiaoke Wang Zhiyun Ouyang 2012Journal of Environmental Sciences2012,24,3:16
4Aging Precipitation Behavior and Mechanical Properties of Inconel 617 Superalloy显示文摘Aging precipitation behavior and mechanical properties of Inconel 617 superalloy aged at 760 ℃ for up to 10000 h were investigated. The results showed that the precipitates of the aged alloy are M23C6 and M6C carbides and γ phase. The carbide particles precipitated both at the grain boundaries and within grains, and the γ phase particles were situated at intragranular sites in the process of aging. The carbide particles were discontinuously dispersed at grain boundaries after aging for 3000 h, while after aged for 5000 h the carbide particles are merged. The precipitates inside grains remained stable even after aging for 10000 h. The hardness was increased for the alloy aged for 300 h up to 3000 h, which was resulted primarily from the precipitation of carbides as discrete particles both at the grain boundaries and inside grains. Small quantity γ precipitates were formed inside grains, to some extent, which contributed to an enhanced hardness. However, a decrease of the hardness was observed after aging for 5000 h. A significant drop in toughness of the alloy aged for 300 h was attributed to the reduction of the bonding interface strength when carbides precipitated at grain boundaries. Thereafter, the toughness decreased slowly with the prolonged aging time. The high temperature tensile properties of the aged alloy are rather stable even aged for 300-3000 h.Yan GUO Bohan WANG Shufang HOU 2013Acta Metallurgica Sinica(English Letters)2013,26,3:12
5Methods for Shale Gas Play Assessment: A Comparison between Silurian Longmaxi Shale and Mississippian Barnett Shale显示文摘Based on field work, organic geochemical analyses and experimental testing, a six-property assessment method for shale gas is proposed. These six properties include organic matter properies, lithofacies, petrophysical properties, gas content, brittleness and local stress field. Due to the features of continuous distribution over a large area and low resource abundance in shale plays, a sweet spot should have these following properties:(a) TOC>2%;(b) brittle minerals content(>40%) and clay minerals(<30%);(c) Ro(>1.1%);(d) porosity(>2%) and permeability(>0.000 1 m D), and(e) effective thickness(30–50 m). Applying these criteria in the Sichuan Basin, the Silurian Longmaxi shale consists of four prospecting sweet spots, including blocks of Changning, Weiyuan, Zhaotong and Fushun-Yongchuan. Although these four blocks have some similarities, different features were usually observed. After comprehensive analyses using the six-property assessment method, the Fushun-Yongan Block ranks the most favorable sweet spot, followed by the Weiyuan Block. For the other two blocks, the Changning Block is better than the Zhaotong Block. By comparing with the Mississippian Barnett shale, characteristics that are crucial for a high-yielding in the Sichuan Basin include a high content of organic matter(TOC>2.5%), a moderate thermal maturity(Ro=0.4%–2%), a high content of brittle minerals(quartz: 30%–45%), a high gas content(>2.5 m3?t-1), and types I and II1 kerogen.Songqi Pan Caineng Zou Zhi Yang Dazhong Dong Yuman Wang Shufang Wang Songtao Wu Jinliang Huang Qun Liu Dule Wang Ziyuan Wang 2015Journal of Earth Science2015,26,2:10
6Recent progress in luminescent materials based on lanthanide complexes intercalated synthetic clays显示文摘Interest in lanthanide complexes in the synthetic clays remains growing considerably during the last decades because of the attractive features of the individuals. Synthetic clays like Laponite~? and Aminoclay show great potentials in building up the luminescent hybrid materials due to their obvious advantages such as high purity, high dispersibility(or solubility) in water to yield translucent gels and clear aqueous solution. Additionally, their strong adsorption capacity for non-polar molecules or complexes is favorable to the formation of water-soluble and aqueous processable luminescent materials. This feature article summarizes the latest developments in the design and preparation of highly luminescent organicinorganic hybrid materials with excellent aqueous process ability based on lanthanide complexes intercalated synthetic clays.Yige Wang Peng Li Shufang Wang Huanrong Li 2019Journal of Rare Earths2019,37,5:10
7Shale Gas Formation and Occurrence in China: An Overview of the Current Status and Future Potential显示文摘Shale gas is one of the most promising unconventional resources both in China and abroad. It is known as a form of self-contained source-reservoir system with large and continuous dimensions. Through years of considerable exploration efforts, China has identified three large shale gas fields in the Fuling, Changning and Weiyuan areas of the Sichuan Basin, and has announced more than 540 billion m^3 of proven shale gas reserves in marine shale systems. The geological theories for shale gas development have progressed rapidly in China as well. For example, the new depositional patterns have been introduced for deciphering the paleogeography and sedimentary systems of the Wufeng shale and Longmaxi shale in the Sichuan Basin. The shale gas storage mechanism has been widely accepted as differing from conventional natural gas in that it is adsorbed on organic matter or a mineral surface or occurs as free gas trapped in pores and fractures of the shale. Significant advances in the techniques of microstructural characterization have provided new insights on how gas molecules are stored in micro- and nano-scale porous shales. Furthermore, newly-developed concepts and practices in the petroleum industry, such as hydraulic fracturing, microseismic monitoring and multiwell horizontal drilling, have made the production of this unevenly distributed but promising unconventional natural gas a reality. China has 10–36 trillion m^3 of promising shale gas among the world's whole predicted technically recoverable reserves of 206.6 trillion m^3. China is on the way to achieving its goal of an annual yield of 30–50 billion m^3 by launching more trials within shale gas projects.ZOU Caineng YANG Zhi PAN Songqi CHEN Yanyan LIN Senhu HUANG Jinliang WU Songtao DONG Dazhong WANG Shufang LIANG Feng SUN Shasha HUANG Yong WENG Dingwei 2016Acta Geologica Sinica(English Edition)2016,90,4:9
8Inheritance of Perpetual Blooming in Rosa chinensis ‘Old Blush'显示文摘Perpetual blooming is one of the most important biological and economical traits in modern rose, while the genetic basis underlining the control of this trait is poorly investigated. With an aim in dissecting the genetic determinism of perpetual blooming, we developed six rose populations(OB, W, F1, F2, BC1 OB and BC1W) derived from a WOB population [interspecific diploid hybridization between Rosa chinensis ‘Old Blush'(OB) and R. wichuriana ‘Basye's Thornless'(W)]. Perpetual blooming is absent both in a F1 population with 296 individuals and a BC1 W population(W as the backcross parent) with 150 individuals. However, the perpetual blooming trait showed a typical 3︰1 segregation in a backcross population BC1 OB with OB as the backcross parent. In this population with 300 individuals, 83 plants had the perpetual blooming phenotype while the other 217 featured non-perpetual blooming, indicating that the perpetual blooming trait is very likely controlled by two recessive genes in R. chinensis(rpb1 and rpb2). These genetic data suggest that the inheritance of rose perpetual blooming may be controlled by a complex mechanism.LI Shubin ZHOU Ningning ZHOU Qing YAN Huijun JIAN Hongying WANG Qigang CHEN Min QIU Xianqin ZHANG Hao WANG Shufang LI Shufa TANG Kaixue 2015Horticultural Plant Journal2015,1,2:9
9Synthesis of bifunctional Pt/MgAPO-5 catalysts and their catalytic performance in the hydrogenation of nitrobenzene to p-aminophenol显示文摘MgAPO-5 molecular sieves have been synthesized using diethylaminoethanol as the templating agent in a wide range of the MgO/Al2O3 ratio.The samples were characterized by XRD,SEM,solid state NMR,FT-IR and NH3-TPD.Using MgAPO-5 as acidic supports,bifunctional Pt/MgAPO-5 catalysts were prepared for hydrogenation of nitrobenzene to p-aminophenol (PAP).The results showed that the MgO/Al2O3 ratios influenced the Mg content and the acidity of MgAPO-5 samples,thereby greatly affecting the catalytic performance of Pt/MgAPO-5 catalysts.The selectivity to PAP over Pt/MgAPO-5 was dependent on the amount of strong acid sites of MgAPO-5.When the MgO/Al2O3 molar ratio was 0.5,the synthesized MgAPO-5 sample exhibited the largest amount of strong acid and a highest PAP yield of 41.1% was achieved over Pt/MgAPO-5 catalyst.ShuFang Wang YaDan Jin BeiBei He YanJi Wang XinQiang Zhao 2010Science China Chemistry2010,53,7:9
10Did Ecological Engineering Projects Have a Significant Effect on Large-scale Vegetation Restoration in Beijing-Tianjin Sand Source Region, China? A Remote Sensing Approach显示文摘Aiming for the restoration of degraded ecosystems, many ecological engineering projects have been implemented around the world. This study investigates the ecological engineering project effectiveness on vegetation restoration in the Beijing-Tianjin Sand Source Region(BTSSR) from 2000 to 2010 based on the rain use efficiency(RUE) trend in relation to the land cover. More than half of the BTSSR experienced a vegetation productivity increase from 2000 to 2010, with the increasing intensity being sensitive to the indicators chosen. A clear tendency towards smaller increasing areas was shown when using the net primary productivity(NPP, 51.30%) instead of the accumulated normalized difference vegetation index(59.30%). The short-term variation in the precipitation and intra-seasonal precipitation distribution had a great impact on the remote sensing-based vegetation productivity. However, the residual trends method(RESTREND) effectively eliminated this correlation, while incorporating the variance and skewness of the precipitation distribution increased the models′ ability to explain the vegetation productivity variation. The RUE combined with land cover dynamics was valid for the effectiveness assessment of the ecological engineering projects on vegetation restoration. Particularly, the result based on growing season accumulated normalized difference vegetation index(ΣNDVI) residuals was the most effective, showing that 47.39% of the BTSSR experienced vegetation restoration from 2000 to 2010. The effectiveness of the ecological engineering projects differed for each subarea and was proportional to the strength of ecological engineering. The water erosion region dominated by woodland showed the best restoration, followed by the wind-water erosion crisscross regions, while the wind erosion regions dominated by grassland showed the worst effect. Seriously degraded regions still cover more area in the BTSSR than restored regions. Therefore, more future effort should be put in restoring degraded land.LI Xiaosong WANG Hongyan ZHOU Shufang SUN Bin GAO Zhihai 2016Chinese Geographical Science2016,26,2:8
11Metal-organic frameworks-derived nitrogen-doped carbon supported nanostructured PtNi catalyst for enhanced hydrosilylation of 1-octene显示文摘Here,we successfully developed nano structured PtNi particles supported on n itroge rrdoped carbon(NC),which were obtai ned by carbon izati on of metal-organic frameworks under different temperatures,forming the nano-PtNi/NC-600,nano-PtNi/NC-800,nano-PtNi/NC-900 and nano-PtNi/NC-1000 catalysts.For hydrosilylation of 1-octene,we found that the nano-PtNi/NC-1000 catalyst exhibits higher activity for anti-Markovnikov hydrosilylation of 1-octene than those of nano-PtNi/NC-600,nano-PtNi/NC-800,nano-PtNi/NC-900 catalysts.Experiments have verified that benefiting from obvious charge transfer from nano-PtNi particles to NC support carbonized at 1,000℃,the nano-PtNi/NC-1000 catalyst achieved almost complete conversion and produce exclusive adduct for anti-Markovnikov hydrosilylation of 1-octene.Importantly,the nano-PtNi/NC-1000 catalyst exhibited good reusability for the hydrosilylation reaction.This work provides a new path to optimize electronic structure of catalysts by support modification to enhance electron transfer between metal active species and supports for highly catalytic performance.Junfeng Wen Yuanjun Chen Shufang Ji Jian Zhang Dingsheng Wang and Yadong Li 2019Nano Research2019,12,10:6
12Core-shell fibrous vascular grafts with the nitric oxide releasing property显示文摘Small-diameter vascular grafts with the nitric oxide(NO) releasing property were designed and prepared.Diazeniumdiolated N,N'-dibutyl-1,6-hexanediamine(DBHD/N2O2) was first synthesized as the NO donor and doped into the biocompatible polymer poly(ε-caprolactone)(PCL).The fibrous vascular grafts were fabricated by electrospinning.Despite the reduced platelet adhesion observed on the NO releasing grafts,the cytotoxicity and burst release were apparent,especially at a higher loading level of the NO donor.In order to solve this problem,core-shell structured nanofibers,in which PCL or gelatin is the shell and PCL doped with the NO donor is the core,were fabricated via coaxial electrospinning.The core-shell structure made the NO release more steady and controllable,and the cell compatibility was improved.ZHANG Lei,WANG Kai,ZHAO Qiang,ZHENG WenTing,WANG ZhiHong,WANG ShuFang & KONG DeLing Key Laboratory of Bioactive Materials,Ministry of Education College of Life Science,Nankai University,Tianjin 300071,China 2010Science China Chemistry2010,53,3:6
13Cholesterol-tuned liposomal membrane rigidity directs tumor penetration and anti-tumor effect显示文摘Recently, liposomes have been widely used in cancer therapeutics, but their anti-tumor effects are suboptimal due to limited tumor penetration. To solve this problem, researchers have made significant efforts to optimize liposomal diameters and potentials, but little attention has been paid to liposomal membrane rigidity. Herein, we sought to demonstrate the effects of cholesterol-tuned liposomal membrane rigidity on tumor penetration and anti-tumor effects. In this study, liposomes composed of hydrogenated soybean phospholipids(HSPC), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000](DSPE-PEG2000) and different concentrations of cholesterol were prepared. It was revealed that liposomal membrane rigidity decreased with the addition of cholesterol. Moderate cholesterol content conferred excellent diffusivity to liposomes in simulated diffusion medium, while excessive cholesterol limited the diffusion process. We concluded that the differences of the diffusion rates likely stemmed from the alterations in liposomal membrane rigidity, with moderate rigidity leading to improved diffusion. Next, the in vitro tumor penetration and the in vivo anti-tumor effects were analyzed. The results showed that liposomes with moderate rigidity gained excellent tumor penetration and enhanced anti-tumor effects. These findings illustrate a feasible and effective way to improve tumor penetration and therapeutic efficacy of liposomes by changing the cholesterol content, and highlight the importance of liposomal membrane rigidity.Hangyi Wu Miaorong Yu Yunqiu Miao Shufang He Zhuo Dai Wenyi Song Yuan Liu Sha Song Ejaj Ahmad Dongkai Wang Yong Gan 2019Acta Pharmaceutica Sinica B2019,9,4:5
14Influences of drip and flood irrigation on soil carbon dioxide emission and soil carbon sequestration of maize cropland in the North China Plain显示文摘The need is pressing to investigate soil CO_2(carbon dioxide) emissions and soil organic carbon dynamics under water-saving irrigation practices in agricultural systems for exploring the potentials of soil carbon sequestration. A field experiment was conducted to compare the influences of drip irrigation(DI) and flood irrigation(FI) on soil organic carbon dynamics and the spatial and temporal variations in CO_2 emissions during the summer maize growing season in the North China Plain using the static closed chamber method. The mean CO_2 efflux over the growing season was larger under DI than that under FI. The cumulative CO_2 emissions at the field scale were 1959.10 and 1759.12 g/m^2 under DI and FI, respectively. The cumulative CO_2 emission on plant rows(OR) was larger than that between plant rows(BR) under FI, and the cumulative CO2 emission on the irrigation pipes(OP) was larger than that between irrigation pipes(BP) under DI. The cumulative CO_2 emissions of OP, BP and bare area(BA) under DI were larger than those of OR, BR and BA under FI, respectively. Additionally, DI promoted root respiration more effectively than FI did. The average proportion of root respiration contributing to the soil CO_2 emissions of OP under DI was larger than that of OR under FI. A general conclusion drawn from this study is that soil CO_2 emission was significantly influenced by the soil water content, soil temperature and air temperature under both DI and FI. Larger concentrations of dissolved organic carbon(DOC), microbial biomass carbon(MBC) and total organic carbon(TOC) were observed under FI than those under DI. The observed high concentrations(DOC, MBC, and TOC) under FI might be resulted from the irrigation-associated soil saturation that in turn inhibited microbial activity and lowered decomposition rate of soil organic matter. However, DI increased the soil organic matter quality(the ratio of MBC to TOC) at the depth of 10–20 cm compared with FI. Our results suggest that the transformation from conventional FI to integrated DI can increase the CO2 emissions and DI needs to be combined with other management practices to reduce the CO_2 emissions from summer maize fields in the North China Plain.GUO Shufang QI Yuchun PENG Qin DONG Yunshe HE Yunlong YAN Zhongqing WANG Liqin 2017Journal of Arid Land2017,9,2:5
15Multimodal Identification by Transcriptomics and Multiscale Bioassays of Active Components in Xuanfeibaidu Formula to Suppress Macrophage-Mediated Immune Response显示文摘Xuanfeibaidu Formula (XFBD) is a Chinese medicine used in the clinical treatment of coronavirus disease 2019 (COVID-19) patients. Although XFBD has exhibited significant therapeutic efficacy in clinical practice, its underlying pharmacological mechanism remains unclear. Here, we combine a comprehensive research approach that includes network pharmacology, transcriptomics, and bioassays in multiple model systems to investigate the pharmacological mechanism of XFBD and its bioactive substances. High-resolution mass spectrometry was combined with molecular networking to profile the major active substances in XFBD. A total of 104 compounds were identified or tentatively characterized, including flavonoids, terpenes, carboxylic acids, and other types of constituents. Based on the chemical composition of XFBD, a network pharmacology-based analysis identified inflammation-related pathways as primary targets. Thus, we examined the anti-inflammation activity of XFBD in a lipopolysaccharide-induced acute inflammation mice model. XFBD significantly alleviated pulmonary inflammation and decreased the level of serum proinflammatory cytokines. Transcriptomic profiling suggested that genes related to macrophage function were differently expressed after XFBD treatment. Consequently, the effects of XFBD on macrophage activation and mobilization were investigated in a macrophage cell line and a zebrafish wounding model. XFBD exerts strong inhibitory effects on both macrophage activation and migration. Moreover, through multimodal screening, we further identified the major components and compounds from the different herbs of XFBD that mediate its anti-inflammation function. Active components from XFBD, including Polygoni cuspidati Rhizoma, Phragmitis Rhizoma, and Citri grandis Exocarpium rubrum, were then found to strongly downregulate macrophage activation, and polydatin, isoliquiritin, and acteoside were identified as active compounds. Components of Artemisiae annuae Herba and Ephedrae Herba were found to substantially inhibit endogenous macrophage migration, while the presence of ephedrine, atractylenolide I, and kaempferol was attributed to these effects. In summary, our study explores the pharmacological mechanism and effective components of XFBD in inflammation regulation via multimodal approaches, and thereby provides a biological illustration of the clinical efficacy of XFBD.Lu Zhao Hao Liu Yingchao Wang Shufang Wang Dejin Xun Yi Wang Yiyu Cheng Boli Zhang 2023Engineering2023,,1:5
16Preparation and electrochemical characterization of ultrathin WO3-x/C nanosheets as anode materials in lithium ion batteries显示文摘Keyan Bao Wutao Mao Guangyin Liu Liqun Ye Haiquan Xie Shufang Ji Dingsheng Wang Chen Chen Yadong Li 2017Nano Research2017,10,6:4
17Effect of ambient oxygen pressure on structural, optical and electrical properties of SnO_2 thin films显示文摘Polycrystalline SnO2 thin films were deposited on sapphire substrates at 450°C under different ambient oxygen pressures by pulsed laser deposition technique. The effect of ambient oxygen pressure on the structural, optical and electri- cal properties of SnO2 thin films was studied. X-ray diffraction and Hall measurements show that increasing the ambient oxygen pressure can improve crystallization of the films and decrease resistivity of the films. A violet emission peak cen- tered at 409 nm was observed from photoluminescence measurements for SnO2 films under deposition ambient oxygen pressure above 5 Pa, which is related to the improvement of crystalline of the films.ZHAO Songqing ZHOU Yueliang WANG Shufang ZHAO Kun HAN Peng 2006Rare Metals2006,25,6:4
18Effects and mechanism of freeze-thawing cycles on the soil N2O fluxes in the temperate semi-arid steppe显示文摘High nitrous oxide(N2O) emissions during freeze-thawing period(FTP) have been observed in many different ecosystems. However, the knowledge about the dynamic of soil N_2O emissions and its main driving mechanism during the freeze-thawing processes in grassland ecosystem is still limited. An in-situ experiment was conducted during the FTP on the sites with 0 and 15% surplus of the average rainfall and two levels of N addition(0,10 g N/(m^2·year)) during growing season(marked as W0N0, W15N0, W0N10, W15N10, respectively) to explore the effects of water and N background on soil N_2O emissions during FTPs and the relationship between soil N_2O emissions and environmental factors. The results indicated that water and N treatments conducted during growing season did not show significant effect on the N_2O effluxes of FTP, but the soil mineral N contents of W0N10 treatment were significantly higher than those of W0N0, W15N0, W15N10treatments(p < 0.05). The soil PLFA concentrations of microbial groups monitored during 2015 spring freeze-thawing period(2015S-FTP) were lower than those during winter freeze-thawing period of 2014(2014W-FTP), while cumulative soil N_2O emissions of 2015S-FTP were higher than those of 2014W-FTP. The correlations between soil N_2O effluxes and most of the measured environmental factors were insignificant, multiple stepwise regression analysis indicated that the soil temperature, soil NH_4^+-N content and air temperature were the major environmental factors which significantly influenced the N_2O effluxes during 2014W-FTP, and air temperature and soil water content were the significant influencing factors during 2015S-FTP.Liqin Wang Yuchun Qi Yunshe Dong qin Peng Shufang Guo Yunlong He Zhaolin Li 2017Journal of Environmental Sciences2017,29,6:4
19Characterization of increased cuticular wax mutant and analysis of genes involved in wax biosynthesis in Dianthus spiculifolius显示文摘Cuticular wax formation on the surface of plant leaves is associated with drought-stress tolerance.The identification of wax biosynthesis-related genes will contribute to the genetic improvement of drought resistance in plants.In this study,we characterize a novel Dianthus spiculifolius mutant with increased cuticular wax.The mutant exhibited stronger drought resistance as indicated by less leaf wilting and death,higher leaf relative water content and water retention capacity,and slower water loss and chlorophyll extraction than did the wild type during drought treatment.In the mutant leaves,2730 upregulated and 2151 downregulated differentially expressed genes(DEGs)were identified by transcriptome sequencing.A wax biosynthesis pathway of the identified DEGs was significantly enriched.Finally,three key genes(DsCER1,DsMAH1,and DsWSD1)involved in wax biosynthesis were identified and verified by qPCR.These results suggest that differential expression of DEGs involved in wax biosynthesis may be associated with the increase in cuticular wax in the mutant.Taken together,our results help elucidate wax formation patterns in D.spiculifolius.Furthermore,the DEGs involved in wax biosynthesis identified here may be valuable genetic resources for improving plant stress tolerance through increased accumulation of cuticular wax.Aimin Zhou Enhui Liu Jiao Liu Shuang Feng Shufang Gong Jingang Wang 2018Horticulture Research2018,5,1:4
20Mechanical Properties and Degradability of Electrospun PCL/PLGA Blended Scaffolds as Vascular Grafts显示文摘In our study, the mechanical properties and degradability of vascular grafts made from poly(ε-caprolactone)(PCL) and poly(lactic-co-glycolic acid)(PLGA) at different ratios were investigated. The results showed that the electrospun PCL/PLGA grafts possess good mechanical properties and biodegradability. The tensile and burst strength of the scaffolds met the demands of vascular grafts. In vitro degradation tests indicated that the degradation rate of the materials increased with the percentage of PLGA, and in vivo tests showed that increasing the amount of PLGA is an effective way to promote cell infiltration. Particularly, the electrospun PCL/PLGA blended scaffold with 10% PLGA exhibited a balance of mechanical and degradation properties, making it a promising tissue engineering material for vascular grafts.Jingchen Gao Siyuan Chen Di Tang Li Jiang Jie Shi Shufang Wang 2019Transactions of Tianjin University2019,25,2:4
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