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Fractional crystallization processes of magma beneath the Carlsberg Ridge(57°–65°E)

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Journal of Oceanology and limnology 2020年第1期38卷 75-92页

作者： ZONG Tong HAN Xiqiu liU Jiqiang WANG Yejian qiu Zhongyan YU Xing Key Laboratory of Submarine Geosciences and Prospection of Ministry of Education Ocean University of ChinaQingdao 266100China Key Laboratory of Submarine Geosciences State Oceanic Administration&Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Ocean College Zhejiang UniversityZhoushan 316021China School of Oceanography Shanghai Jiaotong UniversityShanghai 200030China

Fractional crystallization of basaltic magma at variable depths influences strongly the geochemical compositions of mid-ocean ridge basalts(MORBs),especially at slow-spreading mid-ocean *** Carlsberg Ridge is a typical slow-spreading ridge located in the northwestern Indian *** this study,we conducted petrological,geochemical and modelling studies of MORBs collected along the Carlsberg Ridge from 57°-65°E to understand the fractional crystallization processes of magma and the controls on variations in MORB *** results show that the mantle sources beneath the Carlsberg Ridge are heterogeneous even on the local scale of a segment;such heterogeneity may be ubiquitous beneath the Carlsberg *** heterogeneity may be caused by the enriched components resulting in the"DUPAL"anomaly,whereas the effect of pyroxenite on mantle heterogeneity is *** parental melts experienced crystallization of olivine,plagioclase and clinopyroxene prior to eruption,which played a significant role in the major and trace element variations in MORBs from the Carlsberg *** liquid lines of descent(LLDs),deduced from the forward modelling of three parental magma compositions using the Petrolog3 program at pressures between 1 atm and 10 kbar,demonstrate that clinopyroxene joined the olivine and plagioclase *** over-enrichment in highly incompatible elements relative to LLDs may be caused by the processes of replenishment-tapping-crystallization in magma *** calculated crystallization pressures suggest that parental magmas beneath the Carlsberg Ridge experienced moderateto high-pressure crystallization and that crystallization beneath the slow-spreading Carlsberg Ridge may start at upper mantle depths.

关键词： fractional crystallization crystallization pressure mantle heterogeneity Carlsberg Ridge mid-ocean ridge basalt (MORB)

Drought-Tolerant Rice at Molecular Breeding Eras:An Emerging Reality

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Rice science 2024年第2期31卷 179-189页

作者： ZHU Chengqi YE Yuxuan qiu Tian HUANG Yafan YING Jifeng SHEN Zhicheng Institute of Insect Sciences Zhejiang UniversityHangzhou 310058China Performance Plants Inc. 1287 Gardiners RoadKingstonOntario K7P 3J6Canada China National Rice Research Institute Hangzhou 310006China

Rice(Oryza sativa L.)stands as the most significantly influential food crop in the developing world,with its total production and yield stability affected by environmental *** stress impacts about 45%of the world’s rice area,affecting plants at molecular,biochemical,physiological,and phenotypic *** conventional breeding method,predominantly employing single pedigree selection,has been widely utilized in breeding numerous drought-tolerant rice varieties since the Green *** rapid progress in plant molecular biology,hundreds of drought-tolerant QTLs/genes have been identified and tested in rice crops under both indoor and field *** genes have been introgressed into elite germplasm to develop commercially accepted drought-tolerant varieties,resulting in the development of several drought-tolerant rice varieties through marker-assisted selection and genetically engineered *** review provides up-to-date information on proof-of-concept genes and breeding methods in the molecular breeding era,offering guidance for rice breeders to develop drought-tolerant rice varieties.

关键词： conventional breeding drought stress drought tolerant rice genetic engineering marker-assisted selection breeding

Improved Denoising Autoencoder for Maritime Image Denoising and Semantic Segmentation of USV

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China Communications 2020年第3期17卷 46-57页

作者： Yuhang qiu Yongcheng Yang Zhijian lin Pingping Chen Yang Luo Wenqi Huang Electronic Information Engineering Fuzhou UniversityFuzhou 350116China Nautical College Jimei UniversityXiamen 350116China

Unmanned surface vehicle(USV)is currently a hot research topic in maritime communication network(MCN),where denoising and semantic segmentation of maritime images taken by USV have been rarely *** former has recently researched on autoencoder model used for image denoising,but the existed models are too complicated to be suitable for real-time detection of *** this paper,we proposed a lightweight autoencoder combined with inception module for maritime image denoising in different noisy environments and explore the effect of different inception modules on the denoising ***,we completed the semantic segmentation task for maritime images taken by USV utilizing the pretrained U-Net model with tuning,and compared them with original U-Net model based on different ***,we compared the semantic segmentation of noised and denoised maritime images respectively to explore the effect of image noise on semantic segmentation *** studies are provided to prove the feasibility of our proposed denoising and segmentation ***,a simple integrated communication system combining image denoising and segmentation for USV is shown.

关键词： USV denoising autoencoder semantic segmentation U-Net

Spatiotemporal dynamics of vegetation response to permafrost degradation in Northeast China

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Journal of Arid Land 2024年第11期16卷 1562-1583页

作者： qiu lisha SHAN Wei GUO Ying ZHANG Chengcheng liU Shuai YAN Aoxiang Institute of Cold Regions Science and Engineering Northeast Forestry UniversityHarbin 150040China Ministry of Education Observation and Research Station of Permafrost Geo-Environment System in Northeast China Harbin 150040China Collaborative Innovation Centre for Permafrost Environment and Road Construction and Maintenance in Northeast China Harbin 150040China

Permafrost in Northeast China is undergoing extensive and rapid degradation,and it is of great importance to understand the dynamics of vegetation response to permafrost degradation during different periods in this *** on the meteorological station data and MODIS land surface temperature data,we mapped the distribution of permafrost using the surface frost number(SFN)model to analyze the permafrost degradation processes in Northeast China from 1981 to *** investigated the spatiotemporal variation characteristics of vegetation and its response to permafrost degradation during different periods from 1982 to 2020 using the normalized difference vegetation index(NDVI).We further discussed the dominant factors influencing the vegetation dynamics in the permafrost degradation *** indicated that the permafrost area in Northeast China decreased significantly by 1.01×10^(5) km^(2) in the past 40 *** permafrost stability continued to weaken,with large areas of stable permafrost(SP)converted to semi-stable permafrost(SSP)and unstable permafrost(UP)after *** 1982 to 2020,NDVI exhibited a significant decreasing trend in the seasonal frost(SF)region,while it exhibited an increasing trend in the permafrost *** in the UP and SSP regions changed from a significant increasing trend before 2000 to a nonsignificant decreasing trend after *** 78.63%of the permafrost region,there was a negative correlation between the SFN and NDVI from 1982 to *** the SP and SSP regions,the correlation between the SFN and NDVI was predominantly negative,while in the UP region,it was predominantly *** was the dominant factor influencing the NDVI variations in the permafrost region from 1982 to 2020,and the impact of precipitation on NDVI variations increased after *** findings elucidate the complex dynamics of vegetation in the permafrost region of Northeast China and provide deeper insights into the response mechanisms of vegetation

关键词： permafrost degradation surface frost number(SFN) normalized difference vegetation index(NDVI) vegetation response climate change Northeast China

A Study on the Innovations of Rural Planning and Management of Chengdu, Sichuan, China

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China City Planning Review 2016年第3期25卷 58-65页

作者： Zeng fan qiu Jian School of Architecture and Design Southwest Jiaotong University College of Resources Sichuan Agriculture University Southwest Jiaotong University Housing and Urban-Rural Construction Department of Sichuan Province

China has adopted a dual urban-rural administration system for many years which gives far more attention to cities than to rural areas. Designated as a National Comprehensive Reform Experiment Area for Coordinated Urban-Rural Development, Chengdu is one of several areas in China where the practice of rural planning was fi rstly carried out. After the earthquakes in Wenchuan in 2008 and Lushan in 2013, the post-disaster reconstruction further enriched the local capabilities of rural planning and management. The practice of Chengdu demonstrates that the success of rural planning and management depends on two aspects, a well-organized and well-developed legal systems and institutions and bottom-up selfadministration of local residents which incorporates the social relationships of local communities based on clan and blood kinships. This paper introduces the positive experience of Chengdu in rural planning and management that could be benefi cial for other areas in the country.

关键词： bottom-up self-administration Chengdu practice post-disaster reconstruction rural planning rural planning management

Thermal Annealing Characteristics of Detrital Zircon Fission Track Obtained from Natural Borehole Samples

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Journal of Earth Science 2022年第1期33卷 45-56页

作者： Chang'e Cai Nansheng qiu Jian Chang Cleber Jose Soares Hong Chen Chongqing Key Laboratory of Complex Oil and Gas Field Exploration and Development Chongqing University of Science and TechnologyChongqing 401331China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China ChronusCamp Research-Thermochronology Analyses LTD Itapira 13974Brazil

Previous studies proposed thermal simulation experiment to investigate the annealing characteristics of fission tracks in igneous zircon ***,basic research about detrital zircon fission track was relatively *** study discussed the initial track length,annealing temperature and annealing model of zircon fission track by using the measured track lengths obtained from natural borehole samples in the sedimentary basins with different thermal *** results show that the initial track length of zircon fission track is 12.97 μ*** total annealing temperature(Ttotal) of zircon fission track derived from the evolutionary curve of the mean track lengths is approximately 400 ℃.The temperature ranges of 120-230 ℃ corresponds to the partial annealing zone(PAZ),and is lower than the range obtained through thermal annealing *** annealing model is modified based on the measured track *** addition,a functional formula about the mean track length,annealing temperature,and geological time is proposed,and the fitted values of track lengths consist with the measured track lengths in this *** properly understanding the initial track length and annealing behavior of zircon fission track can provide a significant guidance for the study of hydrocarbon accumulation in sedimentary basins.

关键词： zircon detrital zircon fission track initial track length annealing temperature annealing model natural borehole sample

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圆形薄板在任意弹性边界条件下的自由振动分析

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船舶力学 2015年第1期19卷 162-168页

作者：李秋红刘广明薛开王久法王威远哈尔滨工程大学机电工程学院哈尔滨150001

采用改进的Fourier-Bessel级数方法和Rayleigh-Ritz法对任意弹性边界条件下的圆形薄板进行自由振动分析。通过将圆板的位移函数表示为Fourier-Bessel级数和辅助级数的组合,有效地解决了位移函数在边界处的不连续性问题。最后,应用Raylei... 详细信息

采用改进的Fourier-Bessel级数方法和Rayleigh-Ritz法对任意弹性边界条件下的圆形薄板进行自由振动分析。通过将圆板的位移函数表示为Fourier-Bessel级数和辅助级数的组合,有效地解决了位移函数在边界处的不连续性问题。最后,应用Rayleigh-Ritz法建立了圆板自由振动的矩阵方程,所有振动参数可以通过求解矩阵方程得到。方程特征值对应着圆板振动的固有频率,特征向量对应着圆板振动的振型模态。通过数值仿真计算结果与文献、有限元结果对比,证明了该方法的正确性。

关键词：圆板自由振动改进的 Fourier-Bessel 级数任意弹性边界

The 2-axis stress component decoupling of {100} c-Si by using oblique backscattering micro-Raman spectroscopy

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Science China(Physics,Mechanics & Astronomy) 2020年第9期63卷 51-57页

作者： DongHui Fu XiaoYong He LuLu Ma HuaDan Xing Tian Meng Ying Chang Wei qiu Tianjin Key Laboratory of Modern Engineering Mechanics Department of MechanicsTianjin UniversityTianjin 300350China Department of Mechanical Engineering Lamar UniversityBeaumont TX 77710USA Department of Electrical and Computer Engineering University of DelawareNewark DE 19711USA

With the application of strain engineering in microelectronics,complex stress states are introduced into advanced semiconductor ***,there is still a lack of effective metrology for the decoupling analysis of the complex stress states in semiconductor *** paper presents an investigation on the 2-axis stress component decoupling of{100}monocrystalline silicon(c-Si)by using oblique backscattering micro-Raman spectroscopy.A spectral-mechanical model was established,and two practicable methods for actual stress decoupling analyses were *** verification experiments demonstrated the correctness and applicability of the methods proposed in this paper.

关键词： {100}c-Si stress component decoupling oblique backscattering micro-Raman spectroscopy

Nutritional factors and gastric cancer in Zhoushan Islands, China

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World Journal of Gastroenterology 2005年第28期11卷 4311-4316页

作者： Jiong-liang qiu Jian-Ning Zheng Kun Chen Jian-Yue Wang li-Jun Zhang li-Ming Sui Department of Health and Quarantine Ningbo Entry-Exit Inspection and Quarantine BureauNingbo 315012 Zhejiang Province China Department of Epidemiology Zhejiang University School of Public Health Hangzhou 310006 Zhejiang Province China Zhoushan Center for Disease Prevention and Control Zhoushan 316000 Zhejiang Province China Jiangdong Center for Disease Prevention and Control Ningbo 315000 Zhejiang Province China

AIM: To investigate the association between nutrient intakes and high incidence rate of gastric cancer among residents in Zhoushan ***: A frequency-matched design of case-control study was used during the survey on dietary factors and gastric cancer in Zhoushan Islands, China. A total of 103 cases of gastric cancer diagnosed in 2001 were included in the study and 133 controls were randomly selected from the residents in Zhoushan Islands. A food frequency questionnaire was specifically designed for the Chinese dietary pattern to collect information on dietary intake. A computerized database of the dietary and other relative information of each participant was completed. Total calories and 15 nutrients were calculated according to the food composition table and their adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by gender using unconditional logistic regression ***: High intakes of protein, saturated fat, and cholesterol were observed with the increased risk of gastric cancer particularly among males (ORQ4 vsQ1 were 10.3, 3.24, 2.76 respectively). While carbohydrate was a significant high-risk nutrient (ORQ4 vsQ1 = 14.8; Pfor linear trend = 0.024) among females. Regardless of their gender, the cases reported significantly higher daily intake of sodium mainly from salts. As to the nutrients of vitamins A and C, an inversed association with the risk of GC was found. Baseline characteristics of participants were briefly ***: The findings from this study confirm the role of diet-related exposure in the etiology of gastric cancer from the point of view of epidemiology. An increased risk of gastric cancer is associated with high intakes of protein, saturated fat, cholesterol and sodium,while consumption of polyunsaturated fat, vitamin A and ascorbic acid may have a protective effect against gastric cancer.

关键词： Gastric cancer Nutrient intake Case-control Risk factor Protective effect Antioxidants