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| 1 | Preparation and microstructure characterization of a nano-sized Ti^(4+)-doped AgSnO_2 electrical contact material显示文摘A Ti4+-doped nano-structured AgSnO2 material was prepared using sol-gel method and characterized by X-ray diffraction (XRD), transmis-sion electron microscopy (TEM), and scanning electron microscopy (SEM). The results show that Ti4+ cations are successfully doped into the crystal lattice of SnO2, and thus significantly improve the electrical conductivity of the sample. Furthermore, the coating of Ag on Ti4+-doped SnO2 nano-sized particles enhances the surface wettability and enables the resulting AgSnO2 material to have better mechanical properties. | ZHENG Ji LI Songlin DOU Fuqi LI Tonghui | 2009 | Rare Metals2009，28，1： | 24 |
| 2 | Accumulation of soil organic carbon during natural restoration of desertified grassland in China's Horqin Sandy Land显示文摘China's Horqin Sandy Land,a formerly lush grassland,has experienced extensive desertification that caused considerable carbon(C) losses from the plant-soil system.Natural restoration through grazing exclusion is a widely suggested option to sequester C and to restore degraded land.In a desertified grassland,we investigated the C accumulation in the total and light fractions of the soil organic matter from 2005 to 2013 during natural restoration.To a depth of 20 cm,the light fraction organic carbon(LFOC) storage increased by 221 g C/m2(84%) and the total soil organic carbon(SOC) storage increased by 435 g C/m2(55%).The light fraction dry matter content represented a small proportion of the total soil mass(ranging from 0.74% in 2005 to 1.39% in 2013),but the proportion of total SOC storage accounted for by LFOC was remarkable(ranging from 33% to 40%).The C sequestration averaged 28 g C/(m2·a) for LFOC and 54 g C/(m2·a) for total SOC.The total SOC was strongly and significantly positively linearly related to the light fraction dry matter content and the proportions of fine sand and silt+clay.The light fraction organic matter played a major role in total SOC sequestration.Our results suggest that grazing exclusion can restore desertified grassland and has a high potential for sequestering SOC in the semiarid Horqin Sandy Land. | YuQiang LI XueYong ZHAO FengXia ZHANG Tala AWADA ShaoKun WANG HaLin ZHAO TongHui ZHANG YuLin LI | 2015 | Journal of Arid Land2015，7，3： | 21 |
| 3 | Aquaporin-dependent excessive intrauterine fluid accumulation is a major contributor in hyper-estrogen induced aberrant embryo implantation显示文摘 | Ying Zhang Qi Chen He Zhang Qiang Wang Rong Li Yaping Jin Haibin Wang Tonghui Ma Jie Qiao Enkui Duan | 2015 | Cell Research2015，25，1： | 14 |
| 4 | Aquaporin3 is a sperm water channel essential for postcopulatory sperm osmoadaptation and migration显示文摘在到女繁殖的道的从男性的旅行,哺乳动物的精子经验自然渗透的减少(例如在老鼠,从 ~ 在到 ~ 的尾 epididymis 的 415 mOsm 在子宫的洞的 310 mOsm ) 。精子演变为活动性激活利用这张力减退的暴露,同时高效地沉默张力减退的房间胀大的否定影响。以前的生理并且药理学研究显示出那个离子控制隧道的水流入 / 流出活跃地涉及精子的过程体积规定;然而,没有特定的精子蛋白质为这快速的 osmoadaptation 被发现负责。这里,我们报导 aquaporin3 (AQP3 ) 是在老鼠和人的一条精子水隧道。Aqp3 缺乏的精子响应张力减退显示出正常活动性激活,但是显示增加的危险到张力减退的房间胀大,在进入以后,由增加的尾巴弯曲描绘了子宫。精子缺点是在男性女性的繁殖的道转变期间响应生理的张力减退的应力胀大的损害精子体积规定和进步房间的结果。微速摄影的成像表明房间体积扩大在细胞质的微滴开始,强迫尾巴到有角并且由于机械膜段形成像发卡的结构。尾巴变丑妨碍了精子移植进输卵管,导致损害授精并且减少了男富饶。这些数据为精子作为一条必要的膜小径建议 AQP3 平衡 “ 的规章的卷减少(RVD ) ; trade-off”在在生理的张力减退之上胀大的精子活动性和房间之间,从而优化 postcopulatory 精子行为。 | Qi Chen Hongying Peng Li Lei Ying Zhang Haibin Kuang Yujing Cao Qi-xian Shi Tonghui Ma Enkui Duan | 2011 | Cell Research2011，21，6： | 13 |
| 5 | Tectono-Metallogenic System in the Altay Orogenic Belt,China显示文摘The Altay erogenic belt of China is an important metallogenic belt of base metals, rare metals and gold. The main orogenic-metallogenic epoch is the Hercynian (Late Palaeozoic). Hercynian orogeny underwent two tectonic stages: the early volcano-passive continental margin extension (D1-D2) and late subduction-collision (D3-P). There correspondingly developed two different metallogenic systems. One is the stratabound massive sulphide and iron metallogenic system related to volcano-passive continental margin, and the other is the epigenetic gold and granite-associated rare metals system formed by collision. Very few mineralizations were formed during the subduc-tion time. | WANG Jingbin ZHANG Jinhong DING Rufu FANG Tonghui | 2000 | Acta Geologica Sinica(English Edition)2000，74，3： | 12 |
| 6 | Effects of rainfall patterns on annual plants in Horqin Sandy Land, Inner Mongolia of China显示文摘Growth of annual plants in arid environments depends largely on rainfall pulses. An increased understanding of the effects of different rainfall patterns on plant growth is critical to predicting the potential responses of plants to the changes in rainfall regimes, such as rainfall intensity and duration, and length of dry intervals. In this study, we investigated the effects of different rainfall patterns(e.g. small rainfall event with high frequency and large rainfall event with low frequency) on biomass, growth characteristics and vertical distribution of root biomass of annual plants in Horqin Sandy Land, Inner Mongolia of China during the growing season(from May to August) of 2014. Our results showed that the rainfall patterns, independent of total rainfall amount, exerted strong effects on biomass, characteristics of plant growth and vertical distribution of root biomass. Under a constant amount of total rainfall, the aboveground biomass(AGB), belowground biomass(BGB), plant cover, plant height, and plant individual and species number increased with an increase in rainfall intensity. Changes in rainfall patterns also altered the percentage contribution of species biomass to the total AGB, and the percentage of BGB at different soil layers to the total BGB. Consequently, our results indicated that increased rainfall intensity in future may increase biomass significantly, and also affect the growth characteristics of annual plants. | YUE Xiangfei ZHANG Tonghui ZHAO Xueyong LIU Xinping MA Yunhua | 2016 | Journal of Arid Land2016，8，3： | 8 |
| 7 | Impact of land use conversion on soil organic carbon stocks in an agro-pastoral ecotone of Inner Mongolia显示文摘Soil organic carbon(SOC) stocks in terrestrial ecosystems vary considerably with land use types. Grassland, forest, and cropland coexist in the agro-pastoral ecotone of Inner Mongolia, China. Using SOC data compiled from literature and field investigations, this study compared SOC stocks and their vertical distributions among three types of ecosystems. The results indicate that grassland had the largest SOC stock, which was 1.5-and 1.8-folds more than stocks in forest and cropland, respectively. Relative to the stock in 0–100 cm depth, grassland held more than 40% of its SOC stock in the upper 20 cm soil layer; forest and cropland both held over 30% of their respective SOC stocks in the upper 20 cm soil layer. SOC stocks in grazed grasslands were remarkably promoted after ≥20 years of grazing exclusion. Conservational cultivation substantially increased the SOC stocks in cropland, especially in the 0–40 cm depth. Stand ages, tree species, and forest types did not have obvious impacts on forest SOC stocks in the study area likely due to the younger stand ages. Our study implies that soil carbon loss should be taken into account during the implementation of ecological projects, such as reclamation and afforestation, in the arid and semi-arid regions of China. | ZHAO Wei HU Zhongmin LI Shenggong GUO Qun YANG Hao ZHANG Tonghui | 2017 | Journal of Geographical Sciences2017，27，8： | 8 |
| 8 | Expression of aquaporin-1 in SMMC-7221 liver carcinoma cells promotes cell migration显示文摘Migration of tumor cells is a crucial step in tumor invasion and metastasis. Here we provide evidence that aquaporin expression is involved in tumor cell migration. RT-PCR, immunofluorescence and Western blot analysis demonstrated the AQP1 protein expression on the plasma membrane of SMMC-7221 human hepatoma cells. SMMC-7221 cell clones with high (SMMC-7221hPf) and low (SMMC-7221lPf) water permeability were identified by functional assays with corresponding high and low AQP1 expression. Cell migration rate was remarka- bly higher in SMMC-7221hPf cells than SMMC-7221l Pf cells, assessed by Boyden chamber and wound healing assays, whereas cell growth and adhesion were not different. Adenovirus-mediated AQP1 ex- pression in SMMC-7221lPf cells increased their water permeability and migration rate. These results pro- vide the first evidence that aquaporin-mediated membrane water permeability enhances tumor cell migration and may be associated with tumor invasion and metastasis. | LI Yongming FENG Xuechao YANG Hong MA Tonghui | 2006 | Chinese Science Bulletin2006，51，20： | 5 |
| 9 | Nuclear Aurora kinase A switches m^(6)A reader YTHDC1 to enhance an oncogenic RNA splicing of tumor suppressor RBM4显示文摘Aberrant RNA splicing produces alternative isoforms of genes to facilitate tumor progression,yet how this process is regulated by oncogenic signal remains largely unknown.Here,we unveil that non-canonical activation of nuclear AURKA promotes an oncogenic RNA splicing of tumor suppressor RBM4 directed by m^(6)A reader YTHDC1 in lung cancer.Nuclear translocation of AURKA is a prerequisite for RNA aberrant splicing,specifically triggering RBM4 splicing from the full isoform(RBM4-FL)to the short isoform(RBM4-S)in a kinase-independent manner. | SiSi Li YangFan Qi JiaChuan Yu YuChao Hao Bin He MengJuan Zhang ZhenWei Dai TongHui Jiang SuYi Li Fang Huang Ning Chen Jing Wang MengYing Yang DaPeng Liang Fan An JinYao Zhao WenJun Fan YuJia Pan ZiQian Deng YuanYuan Luo Tao Guo Fei Peng ZhiJie Hou ChunLi Wang FeiMeng Zheng LingZhi Xu Jie Xu QingPing Wen BiLian Jin Yang Wang Quentin Liu | 2022 | Signal Transduction and Targeted Therapy2022，7，5： | 4 |
| 10 | Allometric response of perennial Pennisetum centrasiaticum Tzvel to nutrient and water limitation in the Horqin Sand Land of China显示文摘Optimal partitioning theory(OPT)suggests that plants should allocate relatively more biomass to the organs that acquire the most limited resources.The assumption of this theory is that plants trade off the biomass allocation between leaves,stems and roots.However,variations in biomass allocation among plant parts can also occur as a plant grows in size.As an alternative approach,allometric biomass partitioning theory(APT)asserts that plants should trade off their biomass between roots,stems and leaves.This approach can minimize bias when comparing biomass allocation patterns by accounting for plant size in the analysis.We analyzed the biomass allocation strategy of perennial Pennisetum centrasiaticum Tzvel in the Horqin Sand Land of northern China by treating samples with different availabilities of soil nutrients and water,adding snow in winter and water in summer.We hypothesized that P.centrasiaticum alters its pattern of biomass allocation strategy in response to different levels of soil water content and soil nitrogen content.We used standardized major axis(SMA)to analyze the allometric relationship(slope)and intercept between biomass traits(root,stem,leaf and total biomass)of nitrogen/water treatments.Taking plant size into consideration,no allometric relationships between different organs were significantly affected by differing soil water and soil nitrogen levels,while the biomass allocation strategy of P.centrasiaticum was affected by soil water levels,but not by soil nitrogen levels.The plasticity of roots,leaves and root/shoot ratios was‘true’in response to fluctuations in soil water content,but the plasticity of stems was consistent for trade-offs between the effects of water and plant size.Plants allocated relatively more biomass to roots and less to leaves when snow was added in winter.A similar trend was observed when water was added in summer.The plasticity of roots,stems and leaves was a function of plant size,and remained unchanged in response to different soil nitrogen levels. | Wei MAO TongHui ZHANG YuLin LI XueYong ZHAO YingXin HUANG | 2012 | Journal of Arid Land2012，4，2： | 4 |
| 11 | Comparison of soil physico-chemical properties under different land-use and cover types in northeastern China's Horqin Sandy Land显示文摘The Horqin Sandy Land of northeastern China was originally a grassland with plenty of water and lush vegetation dominated by palatable grass species along with sparsely scattered woody species. However, it has experienced severe desertification in recent decades due to its fragile ecology together with inappropriate human activities. Currently, the landscape of the Horqin Sandy Land is dominated by irrigated croplands and sand dunes with different degrees of vegetation cover, as the region has become the most important part of the semiarid agro-pastoral ecotone of northern China. In this study, we compared soil physical and chemical properties under different land-use and cover types(irrigated cropland, rainfed cropland, sandy grassland, fixed dunes, and mobile dunes). We found that soil particle size distribution; organic C, total N, and total mineral element, microelement, and available microelement and nutrient contents; p H; CEC; and bulk density differed significantly among the land-use and cover types. In general, soil quality was highest in the cropland, intermediate in the sandy grassland, and lowest in the dunes. The most important soil quality attribute, soil organic carbon(SOC) storage, decreased in the following order: irrigated cropland(5,699 g/m^2) > sandy grassland(3,390 g/m^2) > rainfed cropland(2,411 g/m^2) > fixed dunes(821 g/m^2) > mobile dunes(463 g/m^2). SOC was significantly positively correlated with a large proportion of the other soil physico-chemical parameters. Our results suggest that the key issue in restoration of the degraded soils will be to increase SOC storage, which would also create a high potential for sequestering soil C in desertified areas of the Horqin Sandy Land. | YuQiang Li JianPeng Zhang XueYong Zhao TongHui Zhang YuLin Li XinPing Liu YinPing Chen | 2016 | Research in Cold and Arid Regions2016，8，6： | 4 |
| 12 | Highly active N-doped carbon encapsulated Pd-Fe intermetallic nanoparticles for the oxygen reduction reaction显示文摘Developing highly efficient non-R catalysts for fuel cells and metal-air batteries is highly desirable but still challenging due to the sluggish oxygen reduction reaction(ORR).Herein,a facile and efficient strategy is demonstrated to prepare N-doped carbon encapsulated ordered Pd-Fe intermetallic(O-Pd-Fe@NC/C)nanoparticles via a one-step thermal annealing method.The obtained O-Pd-Fe@NC/C nanoparticles show enhanced ORR activity,durability and anti-poisoning capacity in both acid and alkaline medium.When O-Pd-Fe@NC/C serving as cathode catalyst for Zn-air battery,it exhibits higher voltage platform and superior cycling performance with respect to the Zn-air battery based on the mixture of Pt/C and Ir/C catalysts.The enhanced electrocatalytic performance can be ascribed to the formation of face-centered tetragonal(fct)Pd-Fe nanoparticles,the protective action of the N-doped carbon layer and the interface confinement effect between them.The in situ formed N-doped carbon shell not only restrains the Pd-Fe ordered intermetallics from aggregating effectively during the thermal annealing process,but also provides a strong anchoring effect to avoid the detachment of Pd-Fe nanoparticles from the carbon support during the potential cycling.This facile carbon encapsulation strategy may also be extended to the preparation of a wide variety of N-doped carbon encapsulated intermetallic compounds for fuel cell application. | Yezhou Hu Yun Lu Xueru Zhao Tao Shen Tonghui Zhao Mingxing Gong Ke Chen Chenglong Lai Jian Zhang Huolin L.Xin Deli Wang | 2020 | Nano Research2020，13，9： | 3 |
| 13 | Afforestation effects on soil microbial abundance, microbial biomass carbon and enzyme activity in dunes of Horqin Sandy Land, northeastern China显示文摘In order to investigate the effects of afforestation on soil microbial abundance, microbial biomass carbon and enzyme activity in sandy dunes, 20-year-old Pinus sylvestris var. mongolica Litv. (PSM) and Populus simonii Carrière (PSC) mature forests were selected in Horqin Sandy Land, and mobile dunes was set as a control (CK). Results show that PSM and PSC plantations can improve soil physicochemical properties and significantly increase microbiological activity in mobile dunes. Soil microbial abundance, microbial biomass carbon and enzyme activity show an order of PS>PSM>CK. Total soil microbial abundance in PSM and PSC was respectively 50.16 and 72.48 times more than that in CK, and the differences were significant among PSM, PSC and CK. Soil microbial biomass carbon in PSM and PSC was respectively 23.67 and 33.34 times more than that in CK, and the difference was insignificant between PSM and PSC. Soil enzyme activity, including dehydrogenase (DEH), peroxidase (PER), protease (PRO), urease (URE) and cellobiohydrolase (CEL) in PSM and PSC were respectively 19.00 and 27.54, 4.78 and 9.89, 4.05 and 8.67, 29.93 and 37.46, and 9.66 and 13.42 times of that in CK. P. sylvestris and P. simonii can effectively improve soil physicochemical and microbiological properties in sandy dunes and fix mobile dunes in Horqin Sandy Land. The C mic :C ratio is an applicable indicator to estimate soil stability and soil water availability, and based on an overall consideration of plantation stability and sustainability, P. sylvestris is better than P. simonii in fixing mobile dunes in sandy land. | ShaoKun Wang XueYong Zhao TongHui Zhang YuQiang Li Jie Lian WenDa Huang JianYing Yun | 2013 | Research in Cold and Arid Regions2013，5，2： | 3 |
| 14 | Effects of Caragana microphylla plantations on organic carbon sequestration in total and labile soil organic carbon fractions in the Horqin Sandy Land, northern China显示文摘Afforestation is conducive to soil carbon(C) sequestration in semi-arid regions. However, little is known about the effects of afforestation on sequestrations of total and labile soil organic carbon(SOC) fractions in semi-arid sandy lands. In the present study, we examined the effects of Caragana microphylla Lam. plantations with different ages(12-and 25-year-old) on sequestrations of total SOC as well as labile SOC fractions such as light fraction organic carbon(LFOC) and microbial biomass carbon(MBC). The analyzed samples were taken from soil depths of 0–5 and 5–15 cm under two shrub-related scenarios: under shrubs and between shrubs with moving sand dunes as control sites in the Horqin Sandy Land of northern China. The results showed that the concentrations and storages of total SOC at soil depths of 0–5 and 5–15 cm were higher in 12-and 25-year-old C. microphylla plantations than in moving sand dunes(i.e., control sites), with the highest value observed under shrubs in 25-year-old C. microphylla plantations. Furthermore, the concentrations and storages of LFOC and MBC showed similar patterns with those of total SOC at the same soil depth. The 12-year-old C. microphylla plantations had higher percentages of LFOC concentration to SOC concentration and MBC concentration to SOC concentration than the 25-year-old C. microphylla plantations and moving sand dunes at both soil depths. A significant positive correlation existed among SOC, LFOC, and MBC, implying that restoring the total and labile SOC fractions is possible by afforestation with C. microphylla shrubs in the Horqin Sandy Land. At soil depth of 0–15 cm, the accumulation rate of total SOC under shrubs was higher in young C. microphylla plantations(18.53 g C/(m^2·a); 0–12 years) than in old C. microphylla plantations(16.24 g C/(m^2·a); 12–25 years), and the accumulation rates of LFOC and MBC under shrubs and between shrubs were also higher in young C. microphylla plantations than in old C. microphylla plantations. It can be concluded that the establishment of C. microphylla in the Horqin Sandy Land may be a good mitigation strategy for SOC sequestration in the surface soils. | SHANG Wen LI Yuqiang ZHAO Xueyong ZHANG Tonghui MA Quanlin TANG Jinnian FENG Jing SU Na | 2017 | Journal of Arid Land2017，9，5： | 3 |
| 15 | The LTR of endogenous retrovirus ev21 retains promoter activity and exhibits tissue specific transcription in chicken显示文摘Endogenous viruses integrate into the host genome and influence the expression of neighboring genes through their long terminal repeats (LTRs). In this study, we analyzed the promoter, enhancer and transcriptional activities of the chicken endogenous retrovirus ev21 LTR. The LTR was cloned into pGL3-basic and pGL3-promoter luciferase vectors in forward and reverse orientation separately. The luciferase activities were detected respectively in chicken embryonic fibroblast cell, human embryonic kidney cell line, human lung carcinoma cell line, Chinese hamster ovary cell line, and murine melanoma cell line. Relative luciferase activity analysis indicated that the ev21 LTR retained bi-directional promoter activity but no detectable enhancer activity in these cells. The constructs containing the LTR and F1 region show stronger promoter activity than the constructs containing only LTR. The transcriptional pattern of ev21 LTR varied in tissues of late feathering White Leghorn chicken at post-hatch day one. Skin exhibits the highest expression in the tissues examed. Collectively, our results indicate that the ev21 LTR exhibits tissue-type specific expression in White Leghorn chicken, and it also have regulatory potential. | LU XiaoQing HAN JinRun LIU XiaoFang LIN TongHui LI YuLin HU XiaoXiang LI Ning | 2009 | Chinese Science Bulletin2009，54，24： | 3 |
| 16 | Facile self-template fabrication of hierarchical nickel-cobalt phosphide hollow nanoflowers with enhanced hydrogen generation performance显示文摘Developing facile methods to construct hierarchical-structured transition metal phosphides is beneficial for achieving high-efficiency hydrogen evolution catalysts.Herein,a self-template strategy of hydrothermal treatment of solid Ni-Co glycerate nanospheres followed by phosphorization is delivered to synthesize hierarchical Ni Co P hollow nanoflowers with ultrathin nanosheet assembly.The microstructure of Ni Co P can be availably tailored by adjusting the hydrothermal treatment temperature through affecting the hydrolysis process of Ni-Co glycerate nanospheres and the occurred Kirkendall effect.Benefitting from the promoted exposure of active sites and affluent mass diffusion routes,the HER performance of the Ni Co P hollow nanoflowers has been obviously enhanced in contrast with the solid Ni Co P nanospheres.The fabricated Ni Co P hollow nanoflowers yield the current density of 10 m A cmà2at small overpotentials of 95 and 127 m V in 0.5 mol Là1H2SO4and 1.0 mol Là1KOH solution,respectively.Moreover,the two-electrode alkaline cell assembled with the Ni Co P and Ir/C catalysts exhibits sustainable stability for overall water splitting.The work provides a simple but efficient method to regulate the microstructure of transition metal phosphides,which is helpful for achieving high-performance hydrogen evolution catalysts based on solid-state metal alkoxides. | Xupo Liu Shaofeng Deng Peifang Liu Jianing Liang Mingxing Gong Chenglong Lai Yun Lu Tonghui Zhao Deli Wang | 2019 | Science Bulletin2019，64，22： | 2 |
| 17 | Ore-forming Fluid and Mineral Source of the Hongshi Copper Deposit in the Kalatage Area, East Tianshan, Xinjiang, NW China显示文摘The Hongshi copper deposit is located in the middle of the Kalatage ore district in the northern segment of the Dananhu-Tousuquan island-arc belt in East Tianshan, Xinjiang, NW China. This study analyses the fluid inclusions and H, O, and S stable isotopic compositions of the deposit. The fluid-inclusion data indicate that aqueous fluid inclusions were trapped in chalcopyrite-bearing quartz veins in the gangue minerals. The homogenization temperatures range from 108°C to 299°C, and the salinities range from 0.5% to 11.8%, indicating medium to low temperatures and salinities. The trapping pressures range from 34.5 MPa to 56.8 MPa. The δ^(18)O_(H_2O) values and δD values of the fluid range from -6.94‰ to -5.33‰ and from -95.31‰ to -48.20‰, respectively. The H and O isotopic data indicate that the ore-forming fluid derived from a mix of magmatic water and meteoric water and that meteoric water played a significant role. The S isotopic composition of pyrite ranges from 1.9‰ to 5.2‰, with an average value of 3.1‰, and the S isotopic composition of chalcopyrite ranges from -0.9‰ to 4‰, with an average value of 1.36‰, implying that the S in the ore-forming materials was derived from the mantle. The introduction of meteoric water decreased the temperature, volatile content, and pressure, resulting in immiscibility. These factors may have been the major causes of the mineralization of the Hongshi copper deposit. Based on all the geologic and fluid characteristics, we conclude that the Hongshi copper deposit is an epithermal deposit. | YU Mingjie WANG Jingbin MAO Qigui FANG Tonghui ZHANG Rui | 2018 | Acta Geologica Sinica(English Edition)2018，92，5： | 2 |
| 18 | Hybrid Structure Reliability Analysis Based on the Damped Newton Method显示文摘This paper presents a hybrid model reliability analysis method based on the damped Newton method with both random and interval variables to solve the hybrid structure reliability problem.The method combines an outer iterative solution and inner layer numerical calculation.In the outer iteration,the method seeks an optimized solution to the interval variable iterative by adding the boundary constraint condition based on the damped Newton optimization theory.In the inner layer solution,the method first reduces the dimension of the random variable through the dimension reduction method,then obtains the first four-order central moment of the function through the application of the Taylor expansion method,and finally calculates the reliability index of the structure according to the fourth-order moment calculation structure of the function.The results of a numerical example and an engineering ten-rod truss structure show that the proposed method can effectively solve the random-interval hybrid reliability problem and has better calculation accuracy than that of the two-layer iterative method. | Hongwei Zheng Guangwei Meng Feng Li Tonghui Wei Wei Luo Yaming Guo | 2020 | Tsinghua Science and Technology2020，25，5： | 2 |
| 19 | Seasonal changes in the relationship between species richness and community biomass in grassland under grazing and exclosure, Horqin Sandy Land, northern China显示文摘How species diversity-productivity relationships respond to temporal dynamics and land use is still not clear in semi-arid grassland ecosystems. We analyzed seasonal changes of the relationships between vegetation cover, plant density, species richness, and above-ground biomass in grasslands under grazing and exclosure in the Horqin Sandy Land of northern China. Our results showed that in grazed and fenced grassland, vegetation cover, richness, and biomass were lower in April than in August, whereas plant density showed a reverse trend. Vegetation cover during the growing season and biomass in June and August were higher in fenced grassland than in grazed grassland, whereas plant density in April and June was lower in fenced grassland than in grazed grassland. A negative relationship between species richness and biomass was found in August in fenced grassland, and in grazed grassland the relationship between plant density and biomass changed from positive in April to negative in August. The relationship between the density of the dominant plant species and the total biomass also varied with seasonal changes and land use (grazing and exclosure). These results suggest that long-term grazing, seasonal changes, and their interaction significantly influence vegetation cover, plant density, and biomass in grasslands. Plant species competition in fenced grassland results in seasonal changes of the relationship between species richness and biomass. Long-term grazing also affects seasonal changes of the density and biomass of dominant plant species, which further affects the seasonal relationship between plant density and biomass in grasslands. Our study demonstrates the importance of temporal dynamics and land use in understanding the relationship between species richness and ecosystem function. | XiaoAn Zuo XueYong Zhao TongHui Zhang ShaoKun Wang YaYong Luo Xin Zhou | 2013 | Research in Cold and Arid Regions2013，5，2： | 2 |
| 20 | Carbon and nitrogen mineralization in soils along a desertification gradient in the semiarid Horqin Sandy Land, Northern China显示文摘This experiment was conducted in three sites along a desertification gradient in Horqin Sandy Land, Northern China. Soils una-mended and amended with five types of plant residue in a wide range of C:N ratios from 9.9 to 82.2 were incubated for 70 days, during which C and N mineralization were measured. Along the desertification gradient from fixed sand dune to semifixed, and mobile sand dune: cumulative CO2-C produced from the unamended soils was 231.6, 193.3 and 61.9 μg/g, respectively, while net inorganic N was 22.9, 17.6 and 0.9 mg/kg. Soils amended with residues produced more CO2-C than the unamended soils across all sites. During the first 10 days, C mineralization rate of residue-amended soils decreased with the increase of C:N ratio at each site. However, the mineralization rates were poorly correlated with the C:N ratio in subsequent stage of incubation. Soils of mobile sand dune amended with higher C:N ratio (more than 32) residues produced less CO2-C than that of fixed and semifixed sand dune. NO3--N was the predominant form of inorganic N during the mineralization process in sandy soils. Carbon-to-nitrogen ratio (C:N) can be regarded as a predictor of the speed of N mineralization in sandy soil. The more C. microphylla residue with the lowest C:N ratio (9.9) added in soils, the more net inorganic N released. Our results suggest that C. microphylla residue when added to soil would potentially provide short-term plant available N and improve the soil quality in sandy land. The desertification process postponed the release of inorganic N from plant residues. | YuQiang Li HaLin Zhao TongHui Zhang YuLin Li XiaoAn Zuo | 2010 | Research in Cold and Arid Regions2010，2，1： | 2 |
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