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Integrated Stratigraphy and Mineralogy of the Doushantuo Formation in Weng’an,South China,and Implications for Ediacaran Phosphogenesis

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Journal of Earth Science 2024年第2期35卷 476-503页

作者： Liangxuan Jiao Zhenbing She Dominic Papineau Yaguan Zhang Matthew S.Dodd Kenan cao qun Chen Guoyong Chen State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan430078China School of Earth Sciences China University of GeosciencesWuhan430047China London Centre for Nanotechnology University College London17-19 Gordon StreetLondonWC1E 6BTUK Department of Earth Sciences University College LondonLondonWC1E 6BTUK Centre for Planetary Science University College London and Birkbeck CollegeLondonWC1E 7HXUK Innovation Center of Ore Resources Exploration Technology in the Region of Bedrock Ministry of Natural Resources of People’s Republic of China’Guiyang550000China Guizhou Bureau of Geology and Mineral Exploration and Development Guiyang550000China

The Ediacaran–Cambrian Phosphogenic Episode is the Earth’s first true phosphogenic event and resulted in worldwide phosphate deposits,which occurred during the processes of the Neoproterozoic Oxygenation *** Ediacaran Doushantuo Formation(ca.635–551 Ma)of Weng’an area in central Guizhou,South China,contains two economic phosphorite beds(the Lower and Upper Phosphorite Beds).This paper presents a detailed stratigraphic,sedimentological and mineralogical study of multiple outcrop and drill core sections of the Doushantuo Formation across the Weng’an area,and identified 11 lithofacies and 4 types of phosphatic *** differences in lithofacies and grain types between the upper and lower phosphate deposits are observed,indicating that the two sets of phosphate deposits are the products of two distinct phosphogenic *** Lower Phosphorite Bed mainly consists of banded and laminated phosphorites,contains micro-oncoids formed by microbially-mediated precipitation and peloids formed by in-situ chemically oscillating reactions,indicating a biochemical and chemical enrichment of phosphorus to sediments during the Early Ediacaran *** Upper Phosphorite Bed is mainly composed of carbonaceous,massive,and stromatolitic phosphorites,contains bioclasts(phosphatized spheroidal fossils),and intraclasts formed by hydrodynamic agitation,suggesting that the major accesses of phosphorus to sediments were the remineralization of organic *** of the two economic phosphorite beds was controlled by two sea-level *** differences have also been documented in contemporaneous phosphate-bearing successions in Brazil and Mangolia,indicating a significant shift in global phosphogenic mechanism during the early and middle Ediacaran,which may be due to the changes in redox conditions in seawater,associated with the Neoproterozoic Oxygenation *** regional active P-cycle processes could produce more free oxygen,which may have contributed to the up

关键词： phosphorite lithofacies phosphatic grains phosphogenic paragenesis phosphorus cycle mineralogy

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Modified variational iteration method for an El Nio Southern Oscillation delayed oscillator

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Chinese Physics B 2012年第2期21卷 51-55页

作者： cao Xiao-qun Song Jun-Qiang Zhu Xiao-Qian Zhang Li-Lun Zhang Wei-Min Zhao Jun School of Computer Science National University of Defense TechnologyChangsha 410073China

This paper studies a delayed air-sea coupled oscillator describing the physical mechanism of El Nino Southern Oscillation. The approximate expansions of the delayed differential equation＇s solution are obtained successfully by the modified variational iteration method. The numerical results illustrate the effectiveness and correctness of the method by comparing with the exact solution of the reduced model.

关键词： air sea coupling nonlinear oscillator modified variational iteration method delayeddifferential equation

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2022年广西包装饮用桶装水污染情况分析

实验室检测

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实验室检测 2024年第1期2卷 30-34页

作者：曹轶群吕仕军缪璐阮海农馥俏金晓兰刘坤广西壮族自治区产品质量检验研究院南宁530200

目的了解2022年广西区内包装饮用桶装水中溴酸盐、大肠菌群、铜绿假单胞菌、亚硝酸盐(以NO_(2)^(-)计)的污染情况。方法根据桶装水类型及检测项目按标准GB 8538—2016《食品安全国家标准饮用天然矿泉水检验方法》、GB 4789.3—2016《食... 详细信息

目的了解2022年广西区内包装饮用桶装水中溴酸盐、大肠菌群、铜绿假单胞菌、亚硝酸盐(以NO_(2)^(-)计)的污染情况。方法根据桶装水类型及检测项目按标准GB 8538—2016《食品安全国家标准饮用天然矿泉水检验方法》、GB 4789.3—2016《食品安全国家标准食品微生物学检验大肠菌群计数》、GB 5009.33—2016《食品安全国家标准食品中亚硝酸盐与硝酸盐的测定》、GB 19298—2014《食品安全国家标准包装饮用水》、GB 2762—2017《食品安全国家标准食品中污染物限量》进行检测判定。结果收集的204批次桶装包装饮用水中,有55批次铜绿假单胞菌检出,检出率约为26.96%。溴酸盐、大肠菌群、亚硝酸盐均无超标。结论大多数产品不存在安全问题,但铜绿假单胞菌的污染情况仍然突出,企业应加强对管道、桶的清洗消毒及运输存贮的规范,以确保产品安全。

关键词：包装饮用水污染物铜绿假单胞菌溴酸盐亚硝酸盐大肠菌群

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Discovery of novel double pyrazole Schiff base derivatives as anti-tobacco mosaic virus(TMV) agents

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Chinese Chemical Letters 2017年第2期28卷 377-382页

作者： Xian-Hai Lv Zi-Li Ren Dong-Dong Li Ban-Feng Ruan Qing-Shan Li Ming-Jie Chu Cheng-Ying Ai Dao-Hong Liu Kai Mo Hai-qun cao School of Plant Protection Anhui Agricultural University Hefei 230036 China School of Biological and Medical Engineering Hefei University of Technology Hefei 230009 China School of Chemical Engineering Nanjing Forestry University Nanjing 210073 China State Key Laboratory of Pharmaceutical Biotechnology Nanjing University Nanjing 210093 China

Many pyrazole derivatives were reported to exhibit highly activity towards tobacco mosaic virus（TMV）.In this work,an optimized pyrazole Schiff base scaffold was designed and introduced to derive novel potential TMV ***-six compounds were synthesized,characterized by elemental analysis,mass spectra and nuclear magnetic resonance（NMR） spectroscopy and evaluated by biological *** bioassay results showed that some of the synthesized compounds exhibited excellent anti-TMV ***,5-chloro-3-methyl-1H-pyrazole contained compound 4j showed ningnanmycin comparable inhibitory activity and can be considered as potential anti-TMV candidate *** molecular docking,compound 4j insert into nucleotide sequence（GAAGUU） of OriRNA stably which revealed nucleotide could be a target of these compounds.

关键词： Pyrazole Schiff base Anti-TMV Molecule docking

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BACE1 in the retina:a sensitive biomarker for monitoring early pathological changes in Alzheimer's disease

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Neural Regeneration Research 2016年第3期11卷 447-453页

作者： Lan Li Jia Luo Dan Chen Jian-bin Tong Le-ping Zeng Yan-qun cao Jian Xiang Xue-gang Luo Jing-ming Shi Hui Wang Ju-fang Huang Department of Anatomy and Neurobiology School of Basic Medical SciencesCentral South University Department of Anesthesiology Third Xiangya Hospital of Central South University Department of Ophthalmology Second Xiangya HospitalCentral South University

Because of a lack of sensitive biomarkers,the diagnosis of Alzheimer＇s disease（AD） cannot be made prior to symptom ***,it is crucial to identify novel biomarkers for the presymptomatic diagnosis of *** brain lesions are a major feature of AD,retinal pathological changes also occur in *** this study,we investigated the temporal changes in β-site APP-cleaving enzyme 1（BACE1） expression in the retina and brain to determine whether it could serve as a suitable biomarker for early monitoring of ***/PS-1 transgenic mice,3,6 and 8 months of age,were used as an experimental group,and age-matched C57/BL6 wild-type mice served as the control *** the Morris water maze test,there were no significant differences in escape latency or in the number of crossings in the target area among mice of different *** with wild-type mice,no changes in learning or memory abilities were detected in transgenic mice at 3 months of ***,compared with wild-type mice,the escape latency was significantly increased in transgenic mice at 6 months,starting on day 3,and at 8 months,starting on day 2,during Morris water maze *** addition,the number of crossings of the target area was significantly decreased in transgenic *** learning and memory abilities of transgenic mice were further worsened at 8 months of *** staining revealed no BACE1 plaques in wild-type mice at 3,6 or 8 months or in transgenic mice at 3 months,but they were clearly found in the entorhinal cortex,hippocampus and prefrontal cortex of transgenic mice at 6 and 8 ***1 expression was not detected in the retina of wild-type mice at 3 months,but weak BACE1 expression was detected in the ganglion cell layer,inner plexiform layer and outer plexiform layer at 6 and 8 *** transgenic mice,BACE1 expression in the ganglion cell layer was increased at 3 months,and BACE1 expression in the ganglion cell layer,inner plexiform layer and outer plex

关键词： nerve regeneration neurodegenerative disease Alzheimer's disease retina amyloid-β β-site amyloid precursor protein cleaving enzyme 1 APP/PS-1 transgenic mouse neural regeneration

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以橡子为碳源制备的空心磁性碳纳米球及其吸附性能

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无机化学学报 2020年第7期36卷 1233-1240页

作者：曹群武世奎李彦内蒙古医科大学药学院呼和浩特010110 北京大学化学与分子工程学院北京100871

以橡子为碳源,通过高温煅烧法制备了粒径均匀的磁性空心碳纳米球(MHCNS)。经过HCl浸泡处理可得MHCNS-1,再经HNO3和NH3·H2O处理得MHCNS-2。MHCNS-2粒径均匀,直径为20~40 nm,球壁厚度为3~5 nm。MHCNS-2的尺寸可通过改变镍离子与氢氧化钾... 详细信息

以橡子为碳源,通过高温煅烧法制备了粒径均匀的磁性空心碳纳米球(MHCNS)。经过HCl浸泡处理可得MHCNS-1,再经HNO3和NH3·H2O处理得MHCNS-2。MHCNS-2粒径均匀,直径为20~40 nm,球壁厚度为3~5 nm。MHCNS-2的尺寸可通过改变镍离子与氢氧化钾的添加量和比例进行调控。通过X射线粉末衍射、扫描电镜、透射电镜、振动样品磁强计等方法对制备的产物进行了表征,进而分析了其生长机制。MHCNS-2对于有机染料亚甲基蓝(MB)的吸附性能的实验结果表明,MHCNS-2具有强吸附性能,当MB溶液浓度为100 mg·L^-1时,吸附量可以达到185 mg·g^-1。MHCNS对布洛芬的载药释药实验结果表明,MHCNS-2载药率可达44%,释药率达70%,有着良好的载药与释药能力。

关键词：磁性空心碳纳米球(MHCNS) 橡子吸附染料载药微球释药性能

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CPN及在军事指挥控制系统建模中的应用

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系统工程理论与实践 2000年第7期20卷 99-105页

作者：曹群毛张燕国防科技大学C~3I系统研究中心湖南长沙410073

简单介绍了着色 Petri网 (CP-网或 CPN)的发展过程和基本原理 ,重点就 CPN在军事 C3I系统建模仿真中的应用进行了探讨 .

关键词： CPN 军事指挥控制系统建模 C^3I系统

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The correlation between rat retinal nerve fiber layer thickness around optic disc by using optical coherence tomography and histological measurements

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International Journal of Ophthalmology(English edition) 2013年第4期6卷 415-421页

作者： Ju-Fang Huang Hui-Min Yu Lei Shang Ruo-Fei Ma Ngobe Akume Cynthia Yan-qun cao Jia Luo Le-Ping Zeng Dan Chen Kun Xiong Department of Anatomy and Neurobiology Central South University School of Basic Medical Sciences Department of Ophthalmology Central South University Third Xiangya Hospital Central South University Xiangya School of Medicine Department of Anatomy Shaoyang Medical College

·AIM: To explore the correlation between the retinal nerve fiber layer (RNFL) thickness by using optical coherence tomography (OCT) and by histological measurements in normal adult rats and optic nerve transected rats. · METHODS: The RNFL thickness of 36 rats was scanned in a circle 3.46mm far from the optic disc by OCT. The two experimental groups were the normal group ( =20 rats) and the optic nerve transected group ( =16 rats). The latter group included 4 groups ( =4 /group) surviving for 1 day, 3, 5 and 7 days. Then the RNFL thickness of the same retina area was also measured by NF -200 immunohistochemical staining method. Linear regression was used to analyze the correlation between the data obtained from these two methods. ·RESULTS: The RNFL thickness of normal right eyes around optic disc by OCT was 72.35 ±5.71μm and that of the left eyes was 72.65 ±5.88μm ( =0.074). The RNFL thickness of the corresponding histological section by immunohistochemistry was 37.54 ±4.05μm (right eyes) and 37.38 ±4.23μm (left eyes) ( =0.059). There was a good correlation between the RNFL thickness measured by OCT and that measured by histology (R 2 =0.8131). After optic nerve transection, the trend of the RNFL thickness was thinner with the prolonged survival time. The correlation of the thickness detected by the above two methods was approximately (R 2 =0.8265). Value of the RNFL thickness in rats around optic disc measured by OCT was obviously higher than that measured by common histological measurement in normal adult rats and optic nerve transected rats. ·CONCLUSION: The RNFL thickness measured by OCT has a strong correlation with that measured by histological method. Through OCT scanning, we found that the thickness of RNFL gradually becomes thinner in a time-dependent manner.

关键词： retinal nerve fiber layer thickness optical coherence tomography optic nerve transection immunohistochemistry staining relevance analysis rat

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基于高斯球的近似共面合并层次细节模型

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软件学报 2000年第12期11卷 1607-1613页

作者：曹卫群鲍虎军彭群生浙江大学CAD&CG国家重点实验室浙江杭州310027

构造场景多层次细节模型是加速图形显示的有效途径 .给出一种基于共面合并自动生成场景多层次细节模型的算法 .此算法将一单位球定义为高斯球 ,并按一定的规则对其进行层次分割 .然后根据各景物面片的法向在高斯球上的分布 ,将具有近似... 详细信息

构造场景多层次细节模型是加速图形显示的有效途径 .给出一种基于共面合并自动生成场景多层次细节模型的算法 .此算法将一单位球定义为高斯球 ,并按一定的规则对其进行层次分割 .然后根据各景物面片的法向在高斯球上的分布 ,将具有近似一致法向的面片划分为面片族 ;在面片族内对相邻面片进行合并 ,生成近似共面区域 ;然后移去其内部点 ,对区域边界重新三角化 .算法还结合临近边界点合并等原则 ,删除对表达场景几何特征重要度低的顶点 .算法利用平面九叉树进行合并操作 ,生成具有多层次细节的场景模型 .实验结果表明。

关键词：多层次细节模型高斯球共面合并计算机图形学

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基于产业集群的可持续发展研究——以东莞IT产业集群为例

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商业研究 2005年第6期 89-91页

作者：曹群哈尔滨工业大学管理学院黑龙江哈尔滨150001

产业集群发展能增强企业竞争力 ,并带来区域经济的发展。但是 ,在产业集群的可持续发展过程中存在诸多问题。以东莞IT产业集群发展为例 ,指出提高集群可持续发展意识、加强区域创新网络的建设、增强高素质人才的培养。

关键词：产业集群 IT产业可持续发展意识东莞宏观调控作用集群发展区域创新网络高素质人才可持续发展研究培养

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