|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Origin and phylogenetic analysis of Tibetan Mastiff based on the mitochondrial DNA sequence显示文摘At present,the Tibetan Mastiff is the oldest and most ferocious dog in the world. However,the origin of the Tibetan Mastiff and its phylogenetic relationship with other large breed dogs such as Saint Bernard are unclear. In this study,the primers were designed accord-ing to the mitochondrial genome sequence of the domestic dog,and the 2,525 bp mitochondrial sequence,containing the whole sequence of Cytochrome b,tRNA-Thr,tRNA-Pro,and control region of the Tibetan Mastiff,was obtained. Using grey wolves and coyotes as out-groups,the Tibetan Mastiff and 12 breeds of domestic dogs were analyzed in phylogenesis. Tibetan Mastiff,domestic dog breeds,and grey wolves were clustered into a group and coyotes were clustered in a group separately. This indicated that the Tibetan Mastiff and the other domestic dogs originated from the grey wolf,and the Tibetan Mastiff belonged to Carnivora,Canidae,Canis,Canis lupus,Canis lupus familiaris on the animal taxonomy. In domestic dogs,the middle and small breed dogs were clustered at first; German Sheepdog,Swedish Elkhound,and Black Russian Terrier were clustered into one group,and the Tibetan Mastiff,Old English Sheepdog,Leonberger,and Saint Bernard were clustered in another group. This confirmed the viewpoint that many of the famous large breed dogs worldwide such as Saint Bernard possibly had the blood lineage of the Tibetan Mastiff,based on the molecular data. According to the substitution rate,we concluded that the approximate divergence time between Tibetan Mastiff and grey wolf was 58,000 years before the present (YBP),and the approximate divergence time between other domestic dogs and grey wolf was 42,000 YBP,demonstrating that the time of origin of the Tibetan Mastiff was earlier than that of the other domestic dogs. | Qifa Li Zhenshan Liu Yinxia Li Xingbo Zhao Liyan Dong Zengxiang Pan Yuanrong Sun Ning Li Yinxue Xu Zhuang Xie | 2008 | Journal of Genetics and Genomics2008，35，6： | 15 |
| 2 | SIX SIGMA OPTIMIZATION IN SHEET METAL FORMING BASED ON DUAL RESPONSE SURFACE MODEL显示文摘在为形成过程的表金属的优化和数字模拟的重复可以导致广泛的计算。另外,在材料的不确定性或处理参数可以在设计质量上有大影响。六个西格马优化方法被建议,由联合双反应表面方法(DRSM ) 和六西格马哲学,到节省计算费用并且改进部分的可靠性和坚韧性。用这个方法,统计技术包括实验的设计和变化的分析,近似模型和六西格马哲学在一起是综合的完成改进质量。形成过程的二表金属作为例子被提供说明建议方法。 | LI Yuqiang CUI Zhenshan ZHANG Dongjuan RUAN Xueyu CHEN Jun | 2006 | Chinese Journal of Mechanical Engineering2006，19，2： | 12 |
| 3 | Scaling of Soil Carbon,Nitrogen,Phosphorus and C:N:P Ratio Patterns in Peatlands of China显示文摘Inspired by the importance of Redfield-type C:N:P ratios in global soils,we looked for analogous patterns in peatlands and aimed at deciphering the potential affecting factors.By analyzing a suite of peatlands soil data(n = 1031),mean soil organic carbon(SOC),total nitrogen(TN) and total phosphorous(TP) contents were 50.51%,1.45% and 0.13%,respectively,while average C:N,C:P and N:P ratios were 26.72,1186.00 and 46.58,respectively.C:N ratios showed smaller variations across different vegetation coverage and had less spatial heterogeneity than C:P and N:P ratios.No consistent C:N:P ratio,though with a general value of 1245:47:1,was found for entire peatland soils in China.The Northeast China,Tibet,Zoigê Plateau and parts of Xinjiang had high soil SOC,TN,TP,and C:P ratio.Qinghai,parts of the lower reaches of the Yangtze River,and the coast zones have low TP and N:P ratio.Significant differences for SOC,TN,TP,C:N,C:P and N:P ratios were observed across groups categorized by predominant vegetation.Moisture,temperature and precipitation all closely related to SOC,TN,TP and their pairwise ratios.The hydrothermal coefficient(RH),defined as annual average precipitation divided by temperature,positively and significantly related to C:N,C:P and N:P ratios,implying that ongoing climate change may prejudice peatlands as carbon sinks during the past 50 years in China. | ZHANG Zhongsheng XUE Zhenshan LYU Xianguo TONG Shouzheng JIANG Ming | 2017 | Chinese Geographical Science2017，27，4： | 9 |
| 4 | Regional features of the temperature trend in China based on Empirical Mode Decomposition显示文摘由实验模式分解方法,我们在超过 700 个车站分析了观察每月平均的温度从 1951 2001 在中国上。同时,每个车站的温度可变性被这个方法计算。 | SUN Xian LIN Zhenshan CHENG Xiaoxia JIANG Chuangye | 2008 | Journal of Geographical Sciences2008，18，2： | 8 |
| 5 | Modelling the Effect of Initial Grain Size on Dynamic Recrystallization Using a Modified Cellular Automata and a Adaptive Response Surface Method显示文摘A modified cellular automata (CA) model of dynamic recrystallization (DRX) and a flow stress-based nucleation parameter identification method have been developed.In the method,the modified CA model,which takes the role of deformation degree on nucleation behavior into consideration,is coupled with an adaptive response surface model (ARSM) to search for the optimum nucleation parameter.The DRX behavior of an oxygen free high conductivity (OFHC) copper with different initial grain sizes has been taken as an example to validate the model.Good agreement is found between the simulated and the experimental results,which demonstrates that the new method can effectively improve the simulation accuracy. | Zhaoyang Jin Zhenshan Cui | 2010 | Journal of Materials Science & Technology2010，26，12： | 6 |
| 6 | Genomic analysis reveals the genetic diversity,population structure,evolutionary history and relationships of Chinese pepper显示文摘Chinese pepper,mainly including Zanthoxylum bungeanum and Zanthoxylum armatum,is an economically important crop popular in Asian countries due to its unique taste characteristics and potential medical uses.Numerous cultivars of Chinese pepper have been developed in China through long-term domestication.To better understand the population structure,demographic history,and speciation of Chinese pepper,we performed a comprehensive analysis at a genome-wide level by analyzing 38,395 genomic SNPs that were identified in 112 cultivated and wild accessions using a high-throughput genomewide genotyping-by-sequencing(GBS)approach.Our analysis provides genetic evidence of multiple splitting events occurring between and within species,resulting in at least four clades in Z.bungeanum and two clades in Z.armatum.Despite no evidence of recent admixture between species,we detected substantial gene flow within species.Estimates of demographic dynamics and species distribution modeling suggest that climatic oscillations during the Pleistocene(including the Penultimate Glaciation and the Last Glacial Maximum)and recent domestication events together shaped the demography and evolution of Chinese pepper.Our analyses also suggest that southeastern Gansu province is the most likely origin of Z.bungeanum in China.These findings provide comprehensive insights into genetic diversity,population structure,demography,and adaptation in Zanthoxylum. | Shijing Feng Zhenshan Liu Yang Hu Jieyun Tian Tuxi Yang Anzhi Wei | 2020 | Horticulture Research2020，7，1： | 6 |
| 7 | Evaluating ischemic stroke with diffusion tensor imaging显示文摘Objective:In recent years,diffusion tensor imaging (DTI) has emerged as a promising tool to study ischemic stroke. The aim of this study is to evaluate the anisotropic changes of cerebral white matter tracks in patients with ischemic stroke using DTI,and investigate the correlation between corticospinal tract damage and muscle strength in such patients during acute ischemia.Method:9 patients with acute ischemic stroke and 9 healthy subjects were examined with T1 weighted magnetic resonance imaging (MRI),T2 weighted MRI and DTI. Fractional anisotropy (FA) was measured and the three-dimensional fibrous band images of bilateral corticospinal tracts were reconstructed. The muscle strength of the affected hand was assessed by Brunnstorm standard[1],which is an internationally recognized measure of movement in hemiplegic patients.Results:①In the control group,there was no significant difference in FA between the bilateral corticospinal tracts,but FA in different white matter structure of the same side was significantly different (t=3.12,P < 0.05). FA of posterior limb of internal capsule was higher than that of knee and anterior limb of internal capsule,FA of anterior limb of internal capsule was the lowest. while in the patient group,FA of the infarcted sites was significantly lower than the contralateral ones (t=5.570,P < 0.01). ②The ipsilateral corticospinal tract demonstrated continuous interruption and the loss of consistent anatomic structure. The involved severity of corticospinal tract had significant correlation with that of muscle strength of the ipsilateral hand (r=0.83,P < 0.01).Conclusion:This study shows that DTI can be used to investigate ischemic stroke and assess ischemic stroke-induced damage. The damaged severity of corticospinal tracts is correlated with that of muscle strength. | Ziqian Chen Ping Ni Youqiang Ye Hui Xiao Gennian Qian Shangwen Xu Jingliang Wang Xizhang Yang Jinhua Chen Zhenshan Shi Biyun Zhang | 2008 | 福州总医院学报2008，15，3： | 6 |
| 8 | b-DAZL:A novel gene in bovine spermatogenesis显示文摘DAZL 基因在 gametogenesis 起一个重要作用。这基因的 Microdeletion 和变化经常在脊椎动物和无脊椎动物与绝育被联系了。这里,包含 DAZL 基因的完全的开的读物框架的 cDNA,它编码通常认为的 RRM RNA 有约束力的蛋白质,被 RT-PCR 从牛的纸巾孤立。孤立的基因被叫作 b-DAZL。基于计算机的地点分析证明 b-DAZL 在染色体 1 的结束附近被定位。b-DAZL 基因和它的脊椎动物相当或相同事物分享了高核苷酸类似(90 94%) 在编码区域并且在 genomic 组织,每由 10 前 ons 和 9 introns 组成。他们的蛋白质产品包含了一个高度保存的 RNA 有约束力的主题,一次唯一的 DAZ 重复,和 PUM2 和 PABP 交往领域。RT-PCR 试金表明 b-DAZL 在睾丸和卵巢被表示。然而,没有信号在无菌的雄的牛牦牛的睾丸被检测。不育的男性的睾丸的微观结构显示出很少的 spermatocytes 但是主要体的房间。这些观察与有有缺点的 DAZL 表示的睾丸的典型显型一致。随后的基因察觉研究显示那抄写拘捕可能在牛牦牛的睾丸导致一个 b-DAZL 抄本缺点。我们的结果建议 b-DAZL 可以涉及精子发生,并且基因的那抄写拘捕在牛牦牛与男绝育被联系。 | Qingbo Zhang Qifa Li Jiahuang Li Xinfu Li Zhenshan Liu Dawei Song Zhuang Xie | 2008 | Progress in Natural Science:Materials International2008，18，10： | 6 |
| 9 | Analysis of IGF2 mRNA expression and its methylation status between cattle yaks and their parents显示文摘Cattle yaks are an F1 hybrid between cattle and yaks and exhibit significant hybrid vigor. However, cattle yaks are sterile males. To study the epigenetic aspects of this reproductive isolation, IGF2 mRNA expression in cattle yaks and their parents and the patterns of the IGF2 differentially methylated regions (DMR) were examined in blood and testes. The results showed that IGF2 expression in cattle yaks' testes was lower than in their parents (P < 0.01). The IGF2 DMR was highly methylated (above 90%) in blood and testes of cattle yaks, yaks and cattle, with the highest level in cattle yaks (P > 0.05). Our study showed that IGF2 plays an important role in bovine spermato-genesis and might be involved in cattle-yak male sterility. The methylation level of the IGF2 DMR was irrelevant to the lower expression of IGF2 in cattle yaks; other factors perhaps play roles in its expression. | Zhenshan Liu Qifa Li Qingbo Zhang Xuguang Qu Liyan Dong Chamba Yang-zom Zhuang Xie Honglin Liu | 2009 | Progress in Natural Science:Materials International2009，19，9： | 5 |
| 10 | Zanthoxylum-specific whole genome duplication and recent activity of transposable elements in the highly repetitive paleotetraploid Z.bungeanum genome显示文摘Zanthoxylum bungeanum is an important spice and medicinal plant that is unique for its accumulation of abundant secondary metabolites,which create a characteristic aroma and tingling sensation in the mouth.Owing to the high proportion of repetitive sequences,high heterozygosity,and increased chromosome number of Z.bungeanum,the assembly of its chromosomal pseudomolecules is extremely challenging.Here,we present a genome sequence for Z.bungeanum,with a dramatically expanded size of 4.23 Gb,assembled into 68 chromosomes.This genome is approximately tenfold larger than that of its close relative Citrus sinensis.After the divergence of Zanthoxylum and Citrus,the lineage-specific whole-genome duplication event q-WGD approximately 26.8 million years ago(MYA)and the recent transposable element(TE)burst~6.41 MYA account for the substantial genome expansion in Z.bungeanum.The independent Zanthoxylum-specific WGD event was followed by numerous fusion/fission events that shaped the genomic architecture.Integrative genomic and transcriptomic analyses suggested that prominent speciesspecific gene family expansions and changes in gene expression have shaped the biosynthesis of sanshools,terpenoids,and anthocyanins,which contribute to the special flavor and appearance of Z.bungeanum.In summary,the reference genome provides a valuable model for studying the impact of WGDs with recent TE activity on gene gain and loss and genome reconstruction and provides resources to accelerate Zanthoxylum improvement. | Shijing Feng Zhenshan Liu Jian Cheng Zihe Li Lu Tian Min Liu Tuxi Yang Yulin Liu Yonghong Liu He Dai Zujun Yang Qing Zhang Gang Wang Jisen Zhang Huifeng Jiang Anzhi Wei | 2021 | Horticulture Research2021，8，1： | 5 |
| 11 | Application of orthogonal experimental design and Tikhonov regularization method for the identification of parameters in the casting solidification process显示文摘The inverse heat conduction method is one of methods to identify the casting simu- lation parameters. A new inverse method was presented according to the Tikhonov regularization theory. One appropriate regularized functional was established, and the functional was solved by the sensitivity coeffcient and Newton-Raphson iteration method. Moreover, the orthogonal experimental design was used to estimate the ap- propriate initial value and variation domain of each variable to decrease the number of iteration and improve the identification accuracy and effciency. It illustrated a detailed case of AlSi7Mg sand mold casting and the temperature measurement ex- periment was done. The physical properties of sand mold and the interfacial heat transfer coeffcient were identified at the meantime. The results indicated that the new regularization method was effcient in overcoming the ill-posedness of the inverse heat conduction problem and improving the stability and accuracy of the solutions. | Dashan SUI Zhenshan CUI | 2009 | Acta Metallurgica Sinica(English Letters)2009，22，1： | 4 |
| 12 | Petrology,Geochemistry,and Sr-Nd-S Isotopic Compositions of the Ore-Hosting Biotite Monzodiorite in the Luanjiahe Gold Deposit,Jiaodong Peninsula,China显示文摘The Jiaodong Peninsula is one of the most important Au ore provinces in China.There is an ongoing debate on the correlation between ore formation and magmatism in this province,because few intrusive rocks exhibit a clear association with ore deposits.A mineralized biotite monzodiorite(BM)stock,with disseminated ore,pervasive phyllic alteration,and no deformation,was found in a borehole in the footwall of the Zhaoping fault within the Luanjiahe Au deposit,which may shed light on this debate.The biotite monzodiorite contains explosion breccias,miarolitic cavities,skeletal and den-dritic quartz,and late-stage evolved aplite dikes,and the in-situδ34S values of the disseminated pyrite which is associated with Au mineralization are-1.7‰ to 7.3‰(mean=3.5‰),indicative of a magmatic-hydrothermal system.These findings,combined with the reported age of 123 Ma,show that the intru-sion has close spatial,temporal,and geochemical relationships with Au mineralization in the area.The biotite monzodiorite is metaluminous,high-K calc-alkaline and shoshonitic,with enrichment in light rare earth elements(REEs)and large-ion lithophile elements(LILEs),depletion in high-field-strength elements(HFSEs),and enriched Sr-Nd isotopic compositions.The intrusion may be the product of par-tial melting of enriched lithospheric mantle with a small lower crustal component.The hydrous,Au-bearing,enriched mantle source,and the strongly oxidized magma that was generated,created fa-vorable conditions for Au mineralization. | Xiaofeng Yao Zhizhong Cheng Zezhong Du Zhenshan Pang Yuquan Yang Kun Liu | 2021 | Journal of Earth Science2021，32，1： | 4 |
| 13 | Molecular Fingerprints of Soil Organic Matter in a Typical Freshwater Wetland in Northeast China显示文摘Natural wetlands are known to store huge amounts of organic carbon in their soils. Despite the importance of this storage,uncertainties remain about the molecular characteristics of soil organic matter(SOM), a key factor governing the stability of soil organic carbon(SOC). In this study, the molecular fingerprints of SOM in a typical freshwater wetland in Northeast China were investigated using pyrolysis gas-chromatography/mass-spectrometry technology(Py-GC/MS). Results indicated that the SOC, total nitrogen(TN),and total sulfur contents of the cores varied between 16.88% and 45.83%, 0.93% and 2.82%, and 1.09% and 3.79%, respectively. The bulk δ^13C and δ^15N varied over a range of 9.85‰, between –26.85‰ and –17.00‰, and between –0.126‰ and 1.002‰, respectively. A total of 134 different pyrolytic products were identified, and they were grouped into alkyl(including n-alkanes(C:0) and n-alkenes(C:1),aliphatics(Al), aromatics(Ar), lignin(Lg), nitrogen-containing compounds(Nc), polycyclic aromatic hydrocarbons(PAHs), phenols(Phs), polysaccharides(Ps), and sulfur-containing compounds(Sc). On average, Phs moieties accounted for roughly 24.11% peak areas of the total pyrolysis products, followed by Lg(19.27%), alkyl(18.96%), other aliphatics(12.39%), Nc compounds(8.08%), Ps(6.49%), aromatics(6.32%), Sc(3.26%), and PAHs(1.12%). Soil organic matter from wetlands had more Phs and Lg and less Nc moieties in pyrolytic products than soil organic matters from forests, lake sediments, pastures, and farmland.δ^13 C distribution patterns implied more C3 plant-derived soil organic matter, but the vegetation was in succession to C4 plant from C3 plant. Significant negative correlations between Lg or Ps proportions and C3 plant proportions were observed. Multiple linear analyses implied that the Ar and Al components had negative effects on SOC. Alkyl and Ar could facilitate ratios between SOC and total nitrogen(C/N), while Al plays the opposite role. Al was positively related to the ratio of dissolved organic carbon(DOC) to SOC. In summary, SOM of wetlands might characterize by more Phs and lignin and less Nc moieties in pyrolytic products. The use of Pyrolysis gas-chromatography/mass-spectrometry(Py-GC/MS) technology provided detailed information on the molecular characteristics of SOM from a typical freshwater wetland. | LI Zhe ZHANG Zhongsheng XUE Zhenshan SONG Xiaolin ZHANG Hongri WU Haitao JIANG Ming LYU Xianguo | 2019 | Chinese Geographical Science2019，29，4： | 4 |
| 14 | xperimental investigation on cumulative propagation of thin film buckling under cyclic load显示文摘As instrument technology is needed for rapid determination of the smaller,thinner and lighter specimens,more stringent demands are related to thin films such as micro-electro-mechanical systems(MEMS),dielectric coatings and electronic packaging.Therefore,the requirement for testing platforms for rapidly determine the mechanical properties of thin films is increasing.Buckling of a film/substrate system could offer a variety of applications,ranging from stretchable electronics to micro-nanoscale metrology.In this paper,a fatigue-loading device has been designed to make the cyclic loading available for investigating the cumulative propagation of thin film buckling.The straight side buckling of thin compressed titanium film with the thickness of 50 nm deposited on organic glass substrates is investigated by using an optical microscope.The cumulative buckling propagation under the cyclic loading of a sequence of peak compression with the frequency 1 Hz is recorded by CCD camera.The buckling extension lengths are calculated by digital image measurement technology. | WANG ShiBin JIA HaiKun LI LinAn SUN Heng CUI DiQiang GUO ZhenShan XUE XiuLi | 2011 | Science China(Technological Sciences)2011，54，6： | 4 |
| 15 | Spatiotemporal evolution and driving factors of China's flash flood disasters since 1949显示文摘This study examines the spatiotemporal evolution of China's flash flood disasters(FFDs) since 1949 and explores driving factors affecting the spatial distribution of historical FFDs. Records of more than 60000 FFDs are examined, and the centroid comparison method is used to reveal the spatiotemporal evolution of FFDs from 1951 to 2015. In particular, the geographical locations of the centroids, degrees of aggregation, and associated movement tendencies are examined to conduct a preliminary analysis of correlations between rainfall, population, and the spatiotemporal evolution of FFDs. Subsequently, using relevant data from 2000 to 2015, three factors relating to FFDs in natural watershed units include namely rainfall, human activity,and the environment of the Earth's surface. The geographical detector method is then employed to explore the effect of these driving factors on the spatial distribution of FFDs. Analysis results show that displacement of the spatial distribution of FFDs since 1949 is correlated with variations in rainfall and population distribution. In addition, it is determined that the distribution of FFDs occurring between 2000 and 2015 have regional differentiation characteristics. However, the effect of rainfall on the distribution of FFDs is more significant than that of human activity or the environment of the Earth's surface, but interactions occur between these latter two factors in disaster-formative environments. Furthermore, results also show that the driving factors of FFDs have significant spatiotemporal heterogeneity. In China, regions at high risk of FFDs include the Sichuan-Chongqing ecological zone, the South China ecological zone, the Yunnan-Guizhou Plateau, and the middle and lower reaches of the Yangtze River, while regions with a low risk of FFDs include the Northwest China arid zone, Qinghai-Tibet Plateau, Inner Mongolian Plateau, and the Northeast China ecological zone. These findings support further studies investigating disaster-formative environments, facilitate FFD risk zoning, and provide a scientific basis for plans to effectively prevent and control FFDs. | Yesen LIU Zhenshan YANG Yaohuan HUANG Changjun LIU | 2018 | Science China Earth Sciences2018，61，12： | 4 |
| 16 | Integrated Modelling of Microstructure Evolution and Mechanical Properties Prediction for Q&P Hot Stamping Process of Ultra‑High Strength Steel显示文摘High strength steel products with good ductility can be produced via Q&P hot stamping process,while the phase transformation of the process is more complicated than common hot stamping since two-step quenching and one-step carbon partitioning processes are involved.In this study,an integrated model of microstructure evolution relating to Q&P hot stamping was presented with a persuasively predicted results of mechanical properties.The transformation of diffusional phase and non-diffusional phase,including original austenite grain size individually,were considered,as well as the carbon partitioning process which affects the secondary martensite transformation temperature and the subsequent phase transformations.Afterwards,the mechanical properties including hardness,strength,and elongation were calculated through a series of theoretical and empirical models in accordance with phase contents.Especially,a modified elongation prediction model was generated ultimately with higher accuracy than the existed Mileiko’s model.In the end,the unified model was applied to simulate the Q&P hot stamping process of a U-cup part based on the finite element software LS-DYNA,where the calculated outputs were coincident with the measured consequences. | Yang Chen Huizhen Zhang Johnston Jackie Tang Xianhong Han Zhenshan Cui | 2020 | Chinese Journal of Mechanical Engineering2020，33，3： | 3 |
| 17 | Catalytic hydrogenation of aromatic nitro compounds by functionalized ionic liquids-stabilized nickel nanoparticles in aqueous phase:The influence of anions显示文摘Two kinds of nickel nanoparticles (NPs) well-dispersed in aqueous phase have been conveniently prepared by reducing nickel(II) salt with hydrazine in the presence of amino group (-NH2) functionalized ionic liquids:1-(3-aminopropyl)-2,3-dimethylimidazolium bromide ([AMMIM][Br]) and 1-(3-aminopropyl)-2,3-dimethylimidazolium acetate ([AMMIM][AcO]).The Ni(0) particles are composed of smaller ones which assemble in a blackberry-like shape.The Ni nanoparticles stabilized with [AMMIM][AcO] are much larger than those stabilized with [AMMIM][Br],and the former unexpectedly give much higher activity in the selective hydrogenation of citral and nitrobenzene (NB) in aqueous phase.The Ni(0) nanocatalysts dispersed in aqueous phase are stable enough to be reused at least five times without significant loss of catalytic activity and selectivity during the catalytic recycles. | HU Yu YU YinYin ZHAO XiuGe YANG HanMing FENG Bo LI Huan QIAO YunXiang HUA Li PAN ZhenYan HOU ZhenShan | 2010 | Science China Chemistry2010，53，7： | 3 |
| 18 | Spatial and Temporal Changes of Wetlands on the Qinghai-Tibetan Plateau from the 1970s to 2010s显示文摘Wetlands on the Qinghai-Tibetan Plateau(QTP) perform a dazzling array of vital ecological functions and are one of the most fragile ecosystems in the world. Timely and accurate information describing wetland resources and their changes over time is becoming more important in their protection and conservation. By using remote sensing data, this study intended to investigate spatial distribution and temporal variations of wetlands on the QTP at different watershed scales from 1970 s to 2010 s. Results show that wetlands on the QTP have undergone widespread degradation from 1970 s to 2010 s, with nearly 6.4% of their area being lost. Areas of freshwater marsh, salt marsh and wet meadow declined by 46.6%, 53.9% and 15.6%, respectively, while lake area increased by 14.6%. The most extensive losses of natural wetlands have occurred in endorheic basins, such as in the Kunlun-Altun-Qilian Drainage Basin and Qiangtang Basin, which shrank by 44.5% and 33.1%, respectively. A pronounced increase in temperature tends to facilitate the evaporation process and reduce water availability for wetlands. One-third of the wetlands on the QTP are under threat of being submerged due to lakes rising in recent years. More research is needed to gain insight into the interaction mechanisms behind observed variations and potential impacts from further warming in the future. | XUE Zhenshan LYU Xianguo CHEN Zhike ZHANG Zhongsheng JIANG Ming ZHANG Kun LYU Yonglei | 2018 | Chinese Geographical Science2018，28，6： | 3 |
| 19 | Review on modeling and simulation of microstructure evolution during dynamic recrystallization using cellular automaton method显示文摘The macro-mechanical properties of metal and alloy are largely depended on their chemical composition and microstructures resulting from the complicated processing and heat treatment history in industrial production. During these thermoplastic processes, dynamic recovery, dynamic recrystallization, static recovery and static recrystallization are the key microstructural evolution mechanisms. Accurate prediction and precise control of the microstructural evolution are of great importance for designers to achieve excellent mechanical properties for metals and alloys through hot working. Up to date, dynamic recrystallization has been recognized as a powerful mechanism for grain refinement. In-depth understanding of the microstructural evolution of dynamic recrystallization and furthermore to accurately predict and control the microstructure evolution during dynamic recrystallization process has become a research focus in the field of plastic processing. Cellular automaton(CA) method has been commonly employed to simulate the microstructure evolution of dynamic recrystallization due to its unique advantages,for example, it is easier to represent topological features and more realistically reflect the grain boundary migration process. In this paper, the basic ideas and characteristics of the CA method are briefly introduced. The physical mechanisms of dynamic recrystallization are summarized. Meanwhile, the state-of-the-art overview of the CA method of simulating the DRX process is introduced. Furthermore, this paper points out several problems that need to be solved urgently and prospects the development trend of the CA method for simulating the microstructure evolution in dynamic recrystallization. | ZHU HuaJia CHEN Fei ZHANG HaiMing CUI ZhenShan | 2020 | Science China(Technological Sciences)2020，63，3： | 3 |
| 20 | Mechanism of combination membrane and electro-winning process on treatment and remediation of Cu^(2+) polluted water body显示文摘Mechanism of treatment and remediation of synthetic Cu2+ polluted water body by membrane and electro-winning combination process was investigated.The influences of electrolysis voltage,pH,and electrolysis time on the metal recovery effciencies were studied.Relationship between trans-membrane pressure drop(△P),additions ratio,initial Cu2+ concentration on operating effciency,stability of membrane and the possibility of water reuse were also investigated.The morphology of membrane and electrodes were observed using scanning electron microscopy(SEM),the composition of surface deposits was ascertained using combined energy dispersive X-ray spectroscopy(EDX) and atomic absorption spectrophotometer.The results showed that using low pressure reverse osmosis(LPRO),Cu2+ concentration could increase from 20 to 100 mg/L or even higher in concentrated solutions and permeate water conductivity could be less than 20 μS/cm.The addition of sodium dodecy/sulfate sodium dodecyl sulfate improved Cu2+ removal effciency,while EDTA had little side influence.In electro-reduction process,using plante electrode cell,Cu2+ concentration could be further reduced to 5 mg/L,and the average current effciency ranged from 9% to 40%.Using 3D electrolysis treatment,Cu2+ concentration could be reduced to 0.5 mg/L with a current effciency range 60%-70%. | ZHANG Linnan WU Yanjun QU Xiaoyan LI Zhenshan NI Jinren | 2009 | Journal of Environmental Sciences2009，21，6： | 3 |
您所在的机构暂未开通此部分的功能，请联系管理员