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16篇 您的检索式:作者名="Shixin Yan"
    题名 作者 年代 出处 被引量
1Spatial patterns and driving forces of land use change in China during the early 21st century显示文摘Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science (LCS) in the study of global environmental change. Based on remotely sensed data of land use change with a spatial resolution of 1 km × 1 km on national scale among every 5 years, this paper designed a new dynamic regionalization according to the comprehensive characteristics of land use change including regional differentiation, physical, economic, and macro-policy factors as well. Spatial pattern of land use change and its driving forces were investigated in China in the early 21st century. To sum up, land use change pattern of this period was characterized by rapid changes in the whole country. Over the agricultural zones, e.g., Huang-Huai-Hai Plain, the southeast coastal areas and Sichuan Basin, a great proportion of fine arable land were engrossed owing to considerable expansion of the built-up and residential areas, resulting in decrease of paddy land area in southern China. The development of oasis agriculture in Northwest China and the reclamation in Northeast China led to a slight increase in arable land area in northern China. Due to the 'Grain for Green' policy, forest area was significantly increased in the middle and western developing regions, where the vegetation coverage was substantially enlarged, likewise. This paper argued the main driving forces as the implementation of the strategy on land use and regional development, such as policies of 'Western Development', 'Revitalization of Northeast', coupled with rapidly economic development during this period.LIU Jiyuan ZHANG Zengxiang XU Xinliang KUANG Wenhui ZHOU Wancun ZHANG Shuwen LI Rendong YAN Changzhen YU Dongsheng WU Shixin JIANG Nan 2010Journal of Geographical Sciences2010,20,4:154
2Spatiotemporal characteristics, patterns, and causes of land-use changes in China since the late 1980s显示文摘Land-use/land-cover 变化(LUCC ) 有连接到人和自然相互作用。瓷器 Land-Use/cover 数据集(CLUD ) 从 1980 年代末在 5 年的间隔定期被更新到 2010,与基于 Landsat TMETM+ 图象的标准过程。陆地使用动态区域化方法被建议分析主要陆地使用变换。在国家规模的陆地使用变化的空间与时间的特征,差别,和原因然后被检验。主要调查结果如下被总结。越过中国的陆地使用变化(LUC ) 在最后 20 年(19902010 ) 里在空间、时间的特征显示了一个重要变化。农田变化的区域在南方减少了并且在北方,而是仍然是的全部的区域增加了几乎未改变。回收农田从东北被转移到西北。布满建筑物陆地很快膨胀了,主要在东方被散布,并且逐渐地展开到中央、西方的中国。树林首先减少了,然后增加但是荒芜的区域是反面。草地继续减少。在中国的 LUC 的不同空间模式被发现在之间迟了第 20 世纪并且早第 21 世纪。原版 13 个 LUC 地区在一些地区被边界的变化由 15 个单位代替。包括的这些变化(1 ) 的主要空间特征加速的扩大布满建筑物在 Huang-Huai-Hai 区域,东南的沿海的区域,长江的中流区域,和四川盆登陆;(2 ) 从东北中国和东方内部蒙古在北方转移了陆地开垦到绿洲在西北中国的农业区域;(3 ) 从在到稻的东北中国的喂雨的农田的连续转变回答;并且(4 ) 为在内部蒙古,黄土高原,和西南的多山的区域的南部的农业牧剧的交错群落的格林工程的谷物的有效性。在最后二十年,尽管在北方的气候变化在农田影响了变化,政策规定和经济驱动力仍然是越过中国的 LUC 的主要原因。在第 21 世纪的第一十年期间,在陆地使用模式驾驶了变化的人为的因素从单程的陆地开发转移了强调到开发和保存。动态区域化方法被用来在单位的 zoning 边界,地区的内部特征,和生长和减少的空间模式分析变化。结果揭示了变化过程的模式,也就是 LUC 的过程和在在不同阶段的特征的地区性的差别。地区的生长和减少在这动态 LUC zoning,在统一边界的变化,和在前者和后者十年之间的变化紧张的特征期间被检验。在为在不同类型和陆地使用的不同区域的变化的陆地使用和原因的模式和过程之间的其他的转变的模式被探索。LIU Jiyuan KUANG Wenhui ZHANG Zengxiang XU Xinliang QIN Yuanwei NING Jia ZHOU Wancun ZHANG Shuwen LI Rendong YAN Changzhe WU Shixin SHI Xuezheng JIANG Nan YU Dongsheng PAN Xianzhang CHI Wenfeng 2014Journal of Geographical Sciences2014,24,2:245
3Cropland redistribution to marginal lands undermines environmental sustainability显示文摘Cropland redistribution to marginal land has been reported worldwide;however,the resulting impacts on environmental sustainability have not been investigated sufficiently.Here we investigated the environmental impacts of cropland redistribution in China.As a result of urbanization-induced loss of high-quality croplands in south China(~8.5 t ha^(-1)),croplands expanded to marginal lands in northeast(~4.5 t ha^(-1)) and northwest China(~2.9 t ha^(-1)) during 1990-2015 to pursue food security.However,the reclamation in these low-yield and ecologically vulnerable zones considerably undermined local environmental sustainability,for example increasing wind erosion(+3.47%),irrigation water consumption(+34.42%),fertilizer use(+20.02%) and decreasing natural habitats(-3.11%).Forecasts show that further reclamation in marginal lands per current policies would exacerbate environmental costs by 2050.The future cropland security risk will be remarkably intensified because of the conflict between food production and environmental sustainability.Our research suggests that globally emerging reclamation of marginal lands should be restricted and crop yield boost should be encouraged for both food security and environmental benefits.Wenhui Kuang Jiyuan Liu Hanqin Tian Hao Shi Jinwei Dong Changqing Song Xiaoyong Li Guoming Du Yali Hou Dengsheng Lu Wenfeng Chi Tao Pan Shuwen Zhang Rafiq Hamdi Zherui Yin Huimin Yan Changzhen Yan Shixin Wu Rendong Li Jiuchun Yang Yinyin Dou Wenbin Wu Liqiao Liang Bao Xiang Shiqi Yang 2022National Science Review2022,9,1:13
4Simultaneous removal of arsenic and antimony from mining wastewater using granular TiO_2:Batch and field column studies显示文摘Coexisting arsenic(As) and antimony(Sb) in mining wastewater is a common and great concern. On-site simultaneous removal of As and Sb from mining wastewater was achieved by using a reusable granular TiO_2 column in this study. To evaluate the accuracy of the scale-up procedure, As and Sb adsorption from wastewater was studied in both large(600 g TiO_2) and small columns(12 g TiO_2) based on the proportional diffusivity rapid small-scale column tests(PD-RSSCTs) design. The comparable As and Sb breakthrough curves obtained from small and large columns confirmed the accuracy of the PD-RSSCT theory in the design of large-scale columns. Meanwhile, the consistent As and Sb adsorption results from batch and column experiments suggested that TiO_2 adsorption for As and Sb can be predicted from bench-scale tests. Charge distribution multi-site complexation(CD-MUSIC) and onedimensional transport modeling integrated in the PHREEQC program were performed to study the adsorption behaviors of As and Sb on the TiO_2 surface. Coexisting ions, such as Ca^(2+), Mg^(2+), and Si^(4+), play an important role in As and Sb adsorption, and the breakthrough curves were well simulated after considering the compound ion effects. The results from this study highlight the surface reactions of As and Sb on TiO_2 and provide a practical way for on-site remediation of industrial wastewater.Shixin Qiu Li Yan Chuanyong Jing 2019Journal of Environmental Sciences2019,31,1:8
5Automatic segmentation of foveal avascular zone based on adaptive watershed algorithm in retinal optical coherence tomography angiography images显示文摘The size and shape of the foveal avascular zone(FAZ)have a strong positive correlation with several vision-threatening ret inovascular diseases.The identification,segmentation and analysis of FAZ are of great significance to clinical diagnosis and treatment.We presented an adaptive watershed algorithm to automatically extract F AZ from retinal optical coherence tomography angiography(OCTA)images.For the traditional watershed algorithm,'over-segmentation'is the most common problem.FAZ is often incorrectly divided into multiple regions by redundant'dams'.This paper analyzed the relationship between the'dams'length and the maximum inscribed circle radius of FAZ,and proposed an adaptive watershed algorithm to solve the problem of'over-segmentation'.Here,132 healthy retinal images and 50 diabetic retinopathy(DR)images were used to verify the accuracy and stability of the algorithm.Three ophthal-mologists were invited to make quan titative and qualitative evaluations on the segmentation results of this algorithm.The quantitative evaluation results show that the correlation coffi-cients between the automatic and manual segmentation results are 0.945(in healthy subjects)and 0.927(in DR patients),respectively.For qualitative evaluation,the percentages of'perfect segmentation'(score of 3)and'good segmentation'(score of 2)are 99.4%(in healthy subjects)and 98.7%(in DR patients),respectively.This work promotes the application of watershed algorithm in FAZ segmentation,making it a useful tool for analyzing and diagnosing eye diseases.Jian Liu Shixin Yan Nan Lu Dongni Yang Chunhui Fan Hongyu Lv Shuanglian Wang in Zhu Yuqian Zhao Yi Wang Zhenhe Ma Yao Yu 2022Journal of Innovative Optical Health Sciences2022,15,1:3
6Population spatialization in China based on night-time imagery and land use data显示文摘Chuiqing Zeng Yi Zhou Shixin Wang Fuli Yan Qing Zhao 2011International Journal of Remote Sensing2011,,24:1
7p53 inhibition provides a pivotal protective effect against ischemia-reperfusion injury in vitro via mTOR signaling显示文摘Xiaomu Li Shixin Gu Yan Ling Chao Shen Xiaoyun Cao Rong Xie 2015Brain Research2015,,:1
8Spatial patterns and driving forces of land use change in China during the early 21st century显示文摘Jiyuan Liu Zengxiang Zhang Xinliang Xu Wenhui Kuang Wancun Zhou Shuwen Zhang Rendong Li Changzhen Yan Dongsheng Yu Shixin Wu Nan Jiang 0,2010,:1
9Efficient grain refinement of Al alloys induced by in-situ nanoparticles显示文摘Grain refinement of Al and Al alloys during the solidification remains a long-term challenge.Here we report a general strategy for efficient grain refinement through instantaneously in-situ forming abundant nanoparticles with concentrated size distribution.The Al-Zn-Mg-Cu alloy and commercial purity Al are respectively refined by using this proposed strategy and the traditional refinement method(adding AlTi-B alloy into Al melt),and the experimental and numerical results indicate that the TiBnanoparticles instantaneously form in the Al melt during the in-situ refinement process.Compared to the traditional refinement treatment method,the new approach not only can promote the high number density of the nucleation sites and narrow their size distribution,but also tremendously attenuates the agglomeration and settlement of the heterogeneous nucleation sites.It exhibits much better grain refinement ability and inhibits the decline of the grain refinement efficiency.This approach may have broad application prospect not only for the grain refinement of Al and Al alloys,but also for the grain refinement of other alloy systems,e.g.steel,magnesium,copper,and so on.Hongxiang Jiang Yan Song Lili Zhang Jie He Shixin Li Jiuzhou Zhao 2022Journal of Materials Science & Technology2022,,29:1
10Population spatialization in China based on night-time imagery and land use data显示文摘Chuiqing Zeng Yi Zhou Shixin Wang Fuli Yan Qing Zhao 2011International Journal of Remote Sensing2011,,24:1
11Phase-separated bienzyme compartmentalization as artificial intracellular membraneless organelles for cell repair显示文摘Implanting artificial organelles in living cells is capable of correcting cellular dysfunctionalities for cell repair and biomedical applications. In this work, phase-separated bienzyme-loaded coacervate microdroplets are established as a model of artificial membraneless organelles in endothelial dysfunctional cells for the cascade enzymatic production of nitric oxide(NO) with a purpose of correcting cellular NO deficiency. We prepared the coacervate microdroplets via liquid-liquid phase separation of oppositely charged polyelectrolytes, in which glucose oxidase/horseradish peroxidase-mediated cascade reaction was compartmented. After the coacervate microdroplets were implanted in NO-deficient dysfunctional cells, the compartments maintained a phase-separated liquid droplet structure, which facilitated a significant enhancement of NO production in the dysfunctional cells. The recovery of NO production was further exploited to inhibit clot formation in blood plasma located in the cell suspension. This demonstrated a proof-of-concept design of artificial organelles in dysfunctional cells for cell repair and anticoagulation-related medical applications. Our results demonstrate an approach for the construction of coacervate droplets through phase separation for the generation of artificial membraneless organelles, which can be designed to provide an array of functionalities in living organisms that have the potential to be used in the field of cell engineering and medical therapy.Yanwen Zhang Shixin Wang Yuling Yan Xiaoxiao He Zefeng Wang Shaohong Zhou Xiaohai Yang Kemin Wang Jianbo Liu 2023Science China Chemistry2023,66,3:0
12SIX1对肿瘤瓦氏效应的转录调控显示文摘文章简介恶性肿瘤不仅是一种基因病,也是一种能量代谢性疾病。即使在氧供应充分的条件下,肿瘤细胞也主要以糖酵解获取能量,称之有氧糖酵解或'Warburg效应'。目前,'Warburg效应'作为肿瘤的一个典型标志已被广泛认可.Ling Li Yingchun Liang Lei Kang 刘阳 高山 Siyu Chen Ying Li Wenye You Qian Dong Tian Hong Zhifeng Yan Shuai Jin 王涛 Wei Zhao Haixing Mai Jun Huang Xiao Han Quanbo Ji Qi Song Chao Yang Shixin Zhao 徐小洁 叶棋浓 2019科学新闻2019,0,2:0
13MULTIUSER DETECTION AND DIVERSITY RECEPTION FOR ASYNCHRONOUS CDMA MOBILE COMMUNICATION显示文摘In CDMA mobile communication systems, multiple access interference can be canceled by multiuser detection technique. The Degradation by channel fading can be reduced by diversity reception. This paper investigates a family of multiuser receivers that combined decor-relating detection, antenna diversity and RAKE multipath diversity. The performance of the multiuser receivers is analyzed. The results demonstrate a significant increase in the performance of the receivers by using multiuser detection and diversity reception.Wang Yan Cheng Shixin (National Communication Research Lab, Southeast University, Nanjing 210096) 1999Journal of Electronics(China)1999,16,2:0
14Effect of Seed Preservation Technique on the Germination of Artemisia annua Seeds显示文摘[Objectives] To explore the techniques of long-term preservation of Artemisia annua. [Methods] Using different storage methods,germination test and statistical analysis,the effect on seed germination of Artemisia annua was studied. [Results] In cold storage,the envelope preservation had the best effect,while the self-sealing bag had the worst effect; under freezing at low temperatures,the hop-pocket preservation had the best effect,while the self-sealing bag effect had the worst effect. In short,under different storage methods,the self-sealing bag had the worst packaging effect,indicating that the ventilation property of self-sealing bag was poor,affecting the seed breathing,thereby affecting the vitality of the seed,and shortening the life of the seed. [Conclusions]The cold storage envelope packaging was the most appropriate way of storage for Artemisia annua seed,and the storage time should be less than 270 d.Fan LIU Yongli XU Zhigang YAN Shugen WEI Shixin FENG 2017Medicinal Plant2017,8,6:0
15A Verifiable Multi-Secret Sharing Scheme Based on Short Integer Solution显示文摘With the possible birth of the quantum computer, traditional secret sharing schemes have been unable to meet security requirements. We proposed a new verifiable multi-secret sharing scheme based on the short integer solution problem. By utilizing a symmetric binary polynomial,k secrets and secret shares can be generated,and then we convert the secret shares into binary string on Zq, which can be identified by one-way anti-collision hash function on the lattice, so that multiple secrets can be reconstructed safely. The advantages mainly focus on verifiability without interaction in the distribution phase and less memory requirement. In a secret sharing scheme,verifiability prevents the dealer to share the wrong shares and forces the participants to submit their shares correctly. Meanwhile, the interaction can be reduced, which means the security is improved. In a multi-secret sharing scheme, releasing the public values is inevitable, this paper has less public values and less size of shares per secret size to reduce the pressure of memory consumption in the proper parameters. In the end, it can also effectively resist the quantum attack.LI Fulin YAN Jiayun ZHU Shixin HU Hang 2023Chinese Journal of Electronics2023,32,3:0
16A Model Describing Solidification Microstructure Evolution in an Inoculated Aluminum Alloys显示文摘A population dynamics-cellular automaton(PD-CA)model is developed to describe the microstructure formation in an inoculated Al alloys.The model involves the dynamics behaviors of the inoculated particles and the nucleation,initial spherical growth of nuclei as well as the subsequent dendritic growth.The model was validated by using the experimental results for the Al-Cu alloys inoculated by Al–Ti–C refiner first,and then used to simulate the detailed solidification process in an inoculated Al–Cu alloy.The results indicate that the TiC is not stable in Al melt.The heterogeneous nucleation process consists of two stages:a very short initial stage dominated by the cooling rate and the later stage dominated by the number of the active TiC.It stops at the very moment the recalescence occurs.The average grains size d of the aluminum alloys aw))inoculated by the Al–Ti–C refiner can be calculated by d(μm)=a·exp(t/60·In(C_(0)/w)/(v_cool·^(t)^(1/3)w(1/3)+b·Int/Q·v^(1/2))cool where Q is the cool factor,C0(%)is the initial solutes composition,w(%)is the additive amount of Al–Ti–C refiner.t(min)is the holding temperature time since the Al–Ti–C refiner is added into the melt.a and b are the constants.Yan Song Hongxiang Jiang Lili Zhang Shixin Li Jiuzhou Zhao Jie He 2021Acta Metallurgica Sinica(English Letters)2021,34,6:0
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