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Differential Effects of Ammonium and nitrate on Growth Performance of Glechoma longituba under Heterogeneous Cd Stress

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Phyton-International Journal of Experimental Botany 2020年第3期89卷 667-679页

作者： Yanwei Feng Wen Lei Rui Gu Ping Zhao shijun ni ningfei Lei College of Earth Sciences Chengdu University of TechnologyChengdu610101China College of Landscape Architecture Sichuan Agricultural UniversityChengdu610101China College of Environment Chengdu University of TechnologyChengdu610101China Geological Party 105 Guizhou Provincial Bureau of Geology and Mineral Exploration and DevelopmentGuiyang550018China

Water,minerals,nutrients,etc.,can be shared by physiological integration among inter-connected ramets of clonal plants.nitrogen plays an important role in alleviating cadmium(Cd)stress for clonal plants.But how different forms of nitrogen affect growth performance of clonal plants subjected to heterogeneous Cd stress still remains poorly understood.A pot experiment was conducted to investigate the differential effects of ammonium and nitrate on growth performance of Glechoma longituba under heterogeneous Cd stress.In the experiment,parent ramets of Glechoma longituba clonal fragments were respectively supplied with modified Hoagland solution containing 7.5 mM ammonium,7.5 mM nitrate or the same volume of nutrient solution without nitrogen.Cd solution with different concentrations(0,0.1 or 2.0 mM)was applied to offspring ramets of the clonal fragments.Compared with control(N-free),nitrogen addition to parent ramets,especially ammonium,significantly improved antioxidant capacity[glutathione(GSH),proline(Pro),peroxidase(POD,)superoxide dismutase(SOD)and catalase(CAT)],PSII activity[maximum quantum yield of PSII(F_(v)/F_(m))and effective quantum yield of PSII(ΦPSII)],chlorophyll content and biomass accumulation of the offspring ramets suffering from Cd stress.In addition,negative effects of nitrate on growth performance of whole clonal fragments were observed under Cd stress with high concentration(2.0 mM).Transportation or sharing of nitrogen,especially ammonium,can improve growth performance of clonal plants under heterogeneous Cd stress.The experiment provides insight into transmission mechanism of nitrogen among ramets of clonal plants suffering from heterogeneous nutrient supply.Physiological integration might be an important ecological strategy for clonal plants adapting to heterogeneous environment stress conditions.

关键词： Clonal plant physiological integration nitrogen form antioxidant capacity chlorophyll fluorescence

富磷水体中铀在水-钠长石界面的吸附机制研究

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矿物岩石 2024年第2期44卷 1-11页

作者：赵永才王新宇施泽明倪师军王瑞麟成都理工大学地球与行星科学学院四川成都610059 地学核技术四川省重点实验室四川成都610059 成都理工大学材料化学与化工学院四川成都610059

磷矿开发、磷肥施用会引起表生水系中铀与磷酸盐浓度的升高。通过吸附试验,探讨了pH、总磷酸盐浓度、固液比和离子强度对富磷水体中铀在水一钠长石界面的吸附机制。研究结果表明:在总磷酸盐浓度为0.2mg/L、固液比为10g/L、离子强度为0.1... 详细信息

磷矿开发、磷肥施用会引起表生水系中铀与磷酸盐浓度的升高。通过吸附试验,探讨了pH、总磷酸盐浓度、固液比和离子强度对富磷水体中铀在水一钠长石界面的吸附机制。研究结果表明:在总磷酸盐浓度为0.2mg/L、固液比为10g/L、离子强度为0.1mol/L、pH=4.0时,钠长石对铀吸附性最强,最大吸附百分比为95%;酸性条件下,相对于无磷酸盐溶液,磷酸盐溶液会增强钠长石对铀的吸附性;碱性条件下,磷酸盐浓度较低时,钠长石对铀吸附性强于无磷酸盐的溶液,但是磷酸盐浓度较高时,钠长石对铀吸附性弱于无磷酸盐的溶液。不同NaCl浓度条件下的吸附实验表明,当2

关键词：富磷水体钠长石吸附铀赋存形态

Assessment of heavy metals contamination in soils of Dexing region, Jiangxi Province, China

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Chinese Journal Of Geochemistry 2006年第B8期25卷 27-28页

作者： Cuihua CHEN shijun ni Binbin HE Chengjiang ZHANG School of Geosciences Chengdu University of Technology Chengdu 610059 China School of Applied Nuclear Techniques ＆ Automatic Engineering Chengdu University of Technology Chengdu 610059 China Institute of Geo-Spatial Information Science and Technology University of Electronic Science and Technology of China Chengdu 610054 China

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基于智能手机的眼科诊断技术应用研究综述

软件导刊 2024年第2期23卷 201-207页

作者：倪佳张培茗胡桐沈佳琳王迎郭世俊上海理工大学健康科学与工程学院上海200093 上海健康医学院医疗器械学院上海201318

对基于智能手机的眼科诊断技术进行综述,分析将智能手机光学成像技术用于眼结构检查的裂隙灯显微镜、眼底成像设备和角膜地形图仪等技术特点。研究可知,智能手机应用于眼科具有较好的便携性、易用性和低成本等优势,能够增加患者尤其是... 详细信息

对基于智能手机的眼科诊断技术进行综述,分析将智能手机光学成像技术用于眼结构检查的裂隙灯显微镜、眼底成像设备和角膜地形图仪等技术特点。研究可知,智能手机应用于眼科具有较好的便携性、易用性和低成本等优势,能够增加患者尤其是医疗资源紧缺地区的患者获得眼科疾病诊断的机会,从而节约专业医疗资源。未来基于智能手机的眼科诊断设备在医院、诊所和社区卫生中心眼科疾病筛查中将有广泛的应用前景,也可在医学院校用于临床教学。

关键词：眼科诊断智能手机裂隙灯显微镜角膜地形图仪检眼镜

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合金元素及热轧工艺对高强钢组织性能的影响

冶金信息导刊 2024年第2期61卷 21-25,66页

作者：查显文王市均江苏飞达控股集团有限公司丹阳市212312 冶金工业信息标准研究院北京100730

采用热力学计算,分析了试验钢各主要合金含量对组织含量和力学性能的影响规律。结果表明,在一定范围内,Mn、Mo、Cr、ni等元素可以提高试验钢的力学性能,质量分数0.3%的Cr元素,可以使其硬度可达到43.6HRC,屈服强度和抗拉强度均可显著提高。

关键词：高强度钢成分优化设计组织性能热力学计算

Segmentation of Remote Sensing Images Based on U-Net Multi-Task Learning

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Computers, Materials & Continua 2022年第11期73卷 3263-3274页

作者： ni Ruiwen Mu Ye Li Ji Zhang Tong Luo Tianye Feng Ruilong Gong He Hu Tianli Sun Yu Guo Ying Li shijun Thobela Louis Tyasi College of Information Technology Jilin Agricultural UniversityChangchun130118China Jilin Province Agricultural Internet of Things Technology Collaborative Innovation Center Changchun130118China Jilin Province Intelligent Environmental Engineering Research Center Changchun130118China Jilin Province Information Technology and Intelligent Agriculture Engineering Research Center Changchun130118China College of Information Technology Wuzhou UniversityWuzhou543003China Guangxi Key Laboratory of Machine Vision and Intelligent Control Wuzhou543003China Department of Agricultural Economics and Animal Production University of LimpopoSovengaPolokwane0727South Africa

In order to accurately segment architectural features in highresolution remote sensing images,a semantic segmentation method based on U-net network multi-task learning is proposed.First,a boundary distance map was generated based on the remote sensing image of the ground truth map of the building.The remote sensing image and its truth map were used as the input in the U-net network,followed by the addition of the building ground prediction layer at the end of the U-net network.Based on the ResNet network,a multi-task network with the boundary distance prediction layer was built.Experiments involving the ISPRS aerial remote sensing image building and feature annotation data set show that compared with the full convolutional network combined with the multi-layer perceptron method,the intersection ratio of VGG16 network,VGG16+boundary prediction,ResNet50 and the method in this paper were increased by 5.15%,6.946%,6.41%and 7.86%.The accuracy of the networks was increased to 94.71%,95.39%,95.30%and 96.10%respectively,which resulted in high-precision extraction of building features.

关键词： Multitasking learning U-net ResNet remote sensing image semantic segmentation

Evolution of isotopic composition and deuterium excess of brines in the Sichuan Basin, China

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Chinese Journal Of Geochemistry 2013年第1期32卷 69-77页

作者： YAN Qiushi GAO Zhiyou ni shijun SHI Zeming YIN Guan Geochemistry Department College of Nuclear Technology and Automatic Engineering Chengdu University of Technology

The isotopic composition and parameters for deuterium excess of brines, which were sampled in the Si-chuan Basin, show obvious regularities of distribution. The brine isotopic composition shows distinct two systems of marine and terrestrial deposits, with the Middle Triassic strata as the boundary. Brine hydrogen isotopic composition of marine deposits is lower while oxygen isotopic composition is higher than that of the SMOW, respectively, indicating that the brines were derived from seawater with different evaporating degrees at different times. From the Sinian strata, up to the Cambrian, Permian Maokou Formation and the Triassic Jialingjiang Formation, the δD values of brines tend to become relatively positive with the strata becoming younger. Brines of terrestrial deposits are considered to have been derived from precipitation and their isotopic composition is close to the globe meteoric water line (GMWL). Brines of transitional deposits between marine and terrestrial ones (the Upper Triassic Xujiahe Formation) have δD and δ18O values falling between the two end members of marine deposit brines and precipitation, indicating that the brines are a mixture of precipitation and vaporing seawater. Water samples from the brine-bearing strata of different ages show various deuterium excesses (d) with an evident decreasing trend as the age of strata gets older and older. Brine-bearing strata of the Triassic Leikoupo-Jialingjiang Formation, the Permian Maokou Formation, the Cambrian and Sinian strata are all carbonate rocks which have experienced intensive water/rock reaction and the deuterium excess essentially changes with time. All brine-bearing-strata surrounding the basin or faults, as well as those brine wells exploited for resources, have been obviously influenced by the precipitation supply. Therefore, the deuterium excesses of their brines have increased to different extents, depending on the amount of involvement of meteoric water. The variation and distribution of d values of the brines from different Trias

关键词：同位素组成四川盆地过量氘卤水震旦纪地层演变中国陆相沉积

Conductivity of Oxalic Acid in Aqueous Solution at Low Concentration

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Chinese Journal of Chemical Engineering 2005年第1期13卷 81-84页

作者：倪良韩世钧 School of Chemistry and Chemical Engineering Jiangsu University Zhenjiang 212013 China Department of Chemistry Zhejiang University Hangzhou 310027 China Department of Chemistry Zhejiang University Hangzhou 310027 China

Oxalic acid is a weak and unsymmetrical bi-basic acid. There exist dissociation and association equilibria among the species in aqueous solution. The molar conductivity of the solution is the sum of the ionic contributions.Based on this idea, a new prediction equation of ionic conductivity was proposed at low concentration. The molar conductivities of the solution and its relevant ions were calculated respectively. The results obtained were in good agreement with those from experiments and the Quint-Viallard equation.

关键词：传导性草酸水溶液浓度非对称电解液化学分析

Prediction of thermodynamic properties of actinide and lanthanide compounds

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Nuclear Science and Techniques 2008年第3期19卷 152-158页

作者： LU Chunhai ni shijun SUN Ying CHEN Wenkai ZHANG Chengjiang Chengdu University of Technology Chengdu 610059 China China Academy of Engineering Physics P.O. Box 919-71 Mianyang 621900 China Department of Chemistry Fuzhou University Fuzhou 350002 China

Several relationship models for thermodynamic functions of actinide and lanthanide compounds are built. The descriptors such as the difference of atomic radii between metal atoms and nonmetal atoms and the molecular mass are used in quantitative structure-activity/property relationships. The relative errors for entropy and heat capacity are less than 20% in the majority of gaseous compounds. Similar results are obtained from solid compounds.

关键词：金属元素化学热力热力学化合物