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聚酰胺纤维异形化对纤维性能的影响 被引量:1
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作者 蔡长庚 许家瑞 《合成纤维工业》 CAS CSCD 北大核心 2003年第5期13-15,共3页
考察了聚酰胺纤维异形化对于纤维拉伸性能、热性能和动态力学性能的影响。结果表明 ,将平直纤维加工成凸端短纤维和竹节状短纤维 ,对纤维拉伸性能的影响不大 ,但纤维的热收缩减小 ,并使纤维的动态力学性能发生一定程度的变化。主要是凸... 考察了聚酰胺纤维异形化对于纤维拉伸性能、热性能和动态力学性能的影响。结果表明 ,将平直纤维加工成凸端短纤维和竹节状短纤维 ,对纤维拉伸性能的影响不大 ,但纤维的热收缩减小 ,并使纤维的动态力学性能发生一定程度的变化。主要是凸端短纤维的储能模量降低 。 展开更多
关键词 聚酰胺纤维 异形化 拉伸 热收缩 松弛 动态力学性能
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轻油蒸汽转化催化剂异形化研究 被引量:1
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作者 石方柱 程玉春 +1 位作者 尹长学 郝树仁 《大氮肥》 CAS 1999年第6期407-410,共4页
对轻油蒸汽转化异形化催化剂的实验室研究及工业装置投样试验结果进行了总结。结果表明,催化剂异形化后较原拉西环堆密度下降10 % 左右,表观活性提高15% ~20% ,机械强度能够满足工业装置使用要求。
关键词 轻油 蒸汽转 异形化 制氢
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乙烯氧乙酰化催化剂颗粒异形化的研究 被引量:2
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作者 赵振兴 王尚弟 +2 位作者 陈甘棠 王祯祺 杨忠伟 《石油化工》 CAS CSCD 北大核心 1994年第12期783-785,共3页
采用颗粒异形化技术研究了球状颗粒开孔孔径和孔数目对乙烯氧乙酰化催化剂活性和选择性的影响。结果表明,适当增加颗粒外表面积,可以提高催化剂的活性和选择性,且单孔颗粒的催化剂性能优子多孔颗粒。
关键词 颗粒异形化 乙烯氧 乙酰 活性
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异形化微波炉用磁控管的研究
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作者 郑文博 蒙林 +3 位作者 孙可杰 李海龙 王彬 殷勇 《真空电子技术》 2022年第3期27-30,41,共5页
微波炉用磁控管作为微波炉中最重要的器件之一,正在朝小型化、扁平化的方向发展,具有广阔的市场前景和巨大的经济效益。针对磁控管扁平化的需求,本文设计了一种十六腔的异形化微波炉用磁控管,阳极筒沿x轴方向长度为48.5 mm、沿y轴方向... 微波炉用磁控管作为微波炉中最重要的器件之一,正在朝小型化、扁平化的方向发展,具有广阔的市场前景和巨大的经济效益。针对磁控管扁平化的需求,本文设计了一种十六腔的异形化微波炉用磁控管,阳极筒沿x轴方向长度为48.5 mm、沿y轴方向宽度为40 mm,阴极沿x轴方向长度12.5 mm、沿y轴方向宽度为4 mm,利用CST仿真软件对异形化磁控管进行建模和仿真分析,该磁控管在工作电压为4300 V、磁通密度为0.17 T的条件下,阳极电流为1.31 A,在2.466 GHz输出了4141 W的峰值输出功率,效率约为73.5%。结果显示对磁控管管芯进行异形化设计后,可以增大阴极发射表面积,在阴极发射能力与圆柱形微波炉磁控管保持一样的情况下,提高了阳极电流和输出功率,占空比为50%时的平均输出功率约为2070 W,输出效率与现有圆柱形微波炉用磁控管的基本一致。 展开更多
关键词 异形化磁控管 谐振系统 磁控管管芯 微波炉
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对“文本细读”异形化的思考
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作者 卓千峰 《福建论坛(社科教育版)》 2009年第7期59-60,共2页
"文本细读",语文教学炙手可热的新名词,教学观摩研讨的话题焦点,教育刊物开设专辑的主题,专家学者讲堂里描述的烂漫之诗……作为裹挟在中国教改大潮中的一线教师。
关键词 文本细读 异形化 教学观摩 小学语文课堂 价值阅读 文本解读 王崧 听说读写能力 小学教育 文学作品
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浅论远古先民的审美意识在原始神话中的反映——以人的异形化形象为例
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作者 李旋翠 《文化创新比较研究》 2019年第15期21-23,共3页
原始神话传说是劳动人民的智慧结晶,是远古先民的生活印记。原始神话中的审美意识是劳动人民的质朴的、不自觉的情感体现和审美意识的表现。本文通过对中国远古神话中塑造的人物形象的分析来探索远古神话中所表现出来的审美意识。主要... 原始神话传说是劳动人民的智慧结晶,是远古先民的生活印记。原始神话中的审美意识是劳动人民的质朴的、不自觉的情感体现和审美意识的表现。本文通过对中国远古神话中塑造的人物形象的分析来探索远古神话中所表现出来的审美意识。主要通过分析人兽同体和人的异形化形象来突出表现远古人们的野性思维和具体化思维产生的审美意识。 展开更多
关键词 原始神话 审美意识 异形化形象 思维
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基础化学开放实验室建设中“同质异形”教学法运用探索 被引量:1
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作者 刘宝林 《科技视界》 2018年第21期130-132,共3页
基础化学实验涵盖常见化学实验基本操作技术,是化学相关学科发展的坚实物质基础。河南大学基础化学实验分中心承担学校七个学院二十多个专业基础化学实验教学任务,在开放实验室进一步优化建设中,探索运用"同质异形"教学法,强... 基础化学实验涵盖常见化学实验基本操作技术,是化学相关学科发展的坚实物质基础。河南大学基础化学实验分中心承担学校七个学院二十多个专业基础化学实验教学任务,在开放实验室进一步优化建设中,探索运用"同质异形"教学法,强化基本实验操作技能训练,强调结合不同学科专业实际创新应用。 展开更多
关键词 开放实验室 “同质”训练 异形化”应用
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催化剂颗粒的形状优化Ⅰ基本几何形状颗粒 被引量:8
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作者 华卫琦 陈丰秋 吕德伟 《化学反应工程与工艺》 CAS CSCD 北大核心 2000年第2期97-102,共6页
从反应工程的角度 ,通过对催化剂颗粒模型的分析和计算 ,对催化剂外形的优化设计进行了研究 ,定义了形状优化的指标参数 -颗粒的相对活性 F,以及异形化形状描述因子 -无因次开孔半径 χ,并提出了颗粒的最佳χ的求解方法 ,在对基本几何形... 从反应工程的角度 ,通过对催化剂颗粒模型的分析和计算 ,对催化剂外形的优化设计进行了研究 ,定义了形状优化的指标参数 -颗粒的相对活性 F,以及异形化形状描述因子 -无因次开孔半径 χ,并提出了颗粒的最佳χ的求解方法 ,在对基本几何形状 (无限大平板、无限长圆柱、球形 )颗粒的异形化后的颗粒模型进行解析求解的基础上提出了简化算法 ,并对颗粒异形化后的χ、Thiele模数φ对 F的影响进行了探讨。 展开更多
关键词 异形化 颗粒模型 有效因子
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催化剂颗粒的形状优化Ⅱ有限长圆柱和常见动力学 被引量:3
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作者 华卫琦 陈丰秋 吕德伟 《化学反应工程与工艺》 CAS CSCD 北大核心 2000年第2期103-108,共6页
从颗粒模型的角度对有限长圆柱催化剂颗粒的外形优化设计 (异形化 )进行了理论研究 ,针对常见的反应动力学形式 ,提出了普遍 Thiele模数的概念和推导方法 ,简化了颗粒模型求解 ,对不同动力学形式下 ,有限长圆柱形催化剂颗粒的形状优化... 从颗粒模型的角度对有限长圆柱催化剂颗粒的外形优化设计 (异形化 )进行了理论研究 ,针对常见的反应动力学形式 ,提出了普遍 Thiele模数的概念和推导方法 ,简化了颗粒模型求解 ,对不同动力学形式下 ,有限长圆柱形催化剂颗粒的形状优化进行了理论分析。 展开更多
关键词 异形化 颗粒级设计 有限长圆柱 动力学
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催化剂颗粒的力学性能与机械强度 被引量:4
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作者 赵庆国 廖晖 李绍芬 《高校化学工程学报》 EI CAS CSCD 北大核心 2000年第2期164-169,共6页
本文将弹性力学方法引入催化剂颗粒内应力分布的计算。实验结果表明:催化剂材料的应力应变关系符合弹性材料的特征;催化剂材料的强度判据可采用最大剪应力准则;催化剂材料的力学性能数据中,弹性模量基本上为常数,泊松系数则明显地... 本文将弹性力学方法引入催化剂颗粒内应力分布的计算。实验结果表明:催化剂材料的应力应变关系符合弹性材料的特征;催化剂材料的强度判据可采用最大剪应力准则;催化剂材料的力学性能数据中,弹性模量基本上为常数,泊松系数则明显地随应变变化,这种现象充分表明了多孔催化剂材料随外界压力的变化自动调节其内部孔率这-本质特征。在实验结果的基础上,本文给出了镍催化剂(以水泥作粘合剂)的力学性能数据,并对三种异形催化剂颗粒的侧向承载能力进行了对比。 展开更多
关键词 剂颗粒 力学性能 机械强度 异形化
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异形前照灯的发展趋向
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作者 周霞仙 《汽车与配件》 1985年第1期33-36,共4页
一、前照灯概况 1.前照灯的功能前照灯有行车光速和会车光束二种。前者能使驾驶员辨认很远的障碍物,后者使对方驾驶员在不眩目的范围内能辨认障碍物。在日本公路运输车辆安全标准中规定:行车光束为夜间能辨认前方100米,会车光束为夜间... 一、前照灯概况 1.前照灯的功能前照灯有行车光速和会车光束二种。前者能使驾驶员辨认很远的障碍物,后者使对方驾驶员在不眩目的范围内能辨认障碍物。在日本公路运输车辆安全标准中规定:行车光束为夜间能辨认前方100米,会车光束为夜间能辨认前方40米的障碍物。 展开更多
关键词 前照灯 配光 公路运输车辆 异形化 视认性 等照度曲线 塑料表面 半封闭式 视认距离 防水构造
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Low-Energy Electron Attachment to Serine Conformers: Shape Resonances and Dissociation Dynamics 被引量:1
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作者 王永峰 田善喜 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第2期173-185,I0001,共14页
Shape resonances of electron-molecule system formed in the low-energy electron attachment to four low-lying conformers of serine (serine 1, serine 2, serine 3, and serine 4) in gas phase are investigated using the q... Shape resonances of electron-molecule system formed in the low-energy electron attachment to four low-lying conformers of serine (serine 1, serine 2, serine 3, and serine 4) in gas phase are investigated using the quantum scattering method with the non-empirical model potentials in single-center expansion. In the attachment energy range of 0-10 eV, three shape resonances for serine 1, serine 2, and serine 4 and four shape resonances for serine 3 are predicted. The one-dimensional potential energy curves of the temporary negative ions of electron-serine are calculated to explore the correlations between the shape resonance and the bond cleavage. The bond-cleavage selectivity of the different resonant states for a certain conformer is demonstrated, and the recent experimental results about the dissociative electron attachment to serine are interpreted on the basis of present calculations. 展开更多
关键词 SERINE Conformational effect Shape resonance Dissociative electron attach-ment
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333.3dtex/18f三叶形粘胶长丝的研制
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作者 鹿红岩 田文智 《人造纤维》 2003年第2期10-13,44,共5页
介绍了纺制333.3dtex/18f三叶形粘胶长丝的工艺条件、喷丝头设计、纺丝成形及成品丝物化指标和特点。研制试验结果表明,333.3dtex/18f三叶粘胶长丝可纺性良好,成品丝截面三枝叶形态完整,异形度高,其物化指标达到GB/T13758-1992一等品水平。
关键词 三叶形 粘胶长丝 研制 异形化 工艺 研制 试验
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仿羽绒圆中空聚酯短纤维试制技术报告
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作者 姜贵森 《聚酯工业》 CAS 1991年第4期39-43,共5页
简介仿羽绒圆中空聚酯纤维的试制原理及前后纺的工艺参数,对工艺过程进行了详尽的探讨,并分析了纺丝温度、冷却成形条件、牵伸过程等对纤维中空度的影响。
关键词 聚酯短纤维 成形条件 纺丝温度 牵伸过程 羽绒服装 空度 松弛热定型 技术报告 异形化 熔体温度
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The New Discoveries of Specific Characteristics of Yulania Spach 被引量:2
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作者 赵东欣 赵东武 孙军 《Agricultural Science & Technology》 CAS 2008年第1期54-59,共6页
The research history and new discoveries of the specific characteristics of Yulania Spach were reported, as to the specific characteristics, such as the terminal , axillary and fascicled similar flower buds,sometimes ... The research history and new discoveries of the specific characteristics of Yulania Spach were reported, as to the specific characteristics, such as the terminal , axillary and fascicled similar flower buds,sometimes polycymes; 2-4 flower types of a plant; two spathe-like stipoles of single flower; drape or overlap of tepals, deep split or shallow split on the edge of tepals. The discoveries could provide valuable information for the further studies on the taxonomic system, anthotaxical evolution, phylogenetic relationship and breeding. 展开更多
关键词 Yulania Spach Specific characteristics New discoveries
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Grain refinement of Mg−Al binary alloys inoculated by in-situ oxidation 被引量:4
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作者 Heng-bin LIAO Li-ling MO +2 位作者 Cheng-bo LI Mei-yan ZHAN Jun DU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第10期3212-3221,共10页
Utilizing oxide inclusion to induce heterogeneous nucleation event is an available method to achieve grain refinement.In this study,Mg−Al binary alloys were refined by inoculation of in-situ oxidation process.Results ... Utilizing oxide inclusion to induce heterogeneous nucleation event is an available method to achieve grain refinement.In this study,Mg−Al binary alloys were refined by inoculation of in-situ oxidation process.Results show that MgO and MgAl_(2)O_(4) phases are primary oxide products for Mg−xAl alloys inoculated by in-situ oxidation.For pure Mg and Mg−1Al alloy,MgO is the only oxide product.MgAl_(2)O_(4) is another oxide product for Mg−xAl alloy as Al content increases to 3 wt.%.For Mg−3Al alloy,average grain size significantly decreases from 1135 to 237μm,with a high grain refining ratio of 79.1%.Both MgO and MgAl_(2)O_(4) possess nucleating potency forα-Mg grain.MgAl_(2)O_(4) exhibits a higher nucleating potency due to the lower misfit withα-Mg.The grain refinement of Mg−xAl alloys inoculated by in-situ oxidation process is attributed to heterogeneous nucleation events ofα-Mg grains on MgO or MgAl_(2)O_(4) particles. 展开更多
关键词 Mg−Al alloy grain refinement heterogeneous nucleation MGO MgAl_(2)O_(4)
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Different cell kinetic changes in rat stomach cancer after treatment with celecoxib or indomethacin: Implications on chemoprevention 被引量:38
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作者 JunYu Bao-DongTang +7 位作者 WaiK.Leung Ka-FaiTo AlfaH.C.Bai Zhi-RongZeng Po-KiMa MinnieY.Y.Go Pin-JinHu JosephJ.Y.Sung 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第1期41-45,共5页
AIM: Mechanisms underlying the chemopreventive effects of cyclooxygenase (COX) inhibitors remain elusive. We have previously shown that celecoxib but not indomethacin could prevent carcinogen-induced gastric cancer de... AIM: Mechanisms underlying the chemopreventive effects of cyclooxygenase (COX) inhibitors remain elusive. We have previously shown that celecoxib but not indomethacin could prevent carcinogen-induced gastric cancer development in Wistar rats. This chemopreventive effect appeared to be independent of COX-2 and prostaglandin (PG) E2 suppression since the lowest PGE2 was obtained in indomethacin group.This study compared the cell kinetic changes in stomachs of rats after treatment with celecoxib (5, 10, 20 mg/(kg·d)) or indomethacin (3 mg/(kg·d)) to gain more insights into the chemopreventive mechanism.METHODS: The apoptosis and proliferation indexes in gastric tumor, adjacent non-cancer tissues and normal gastric tissues were determined. Apoptosis was quantified by apoptotic nuclei counting and TUNEL, whereas proliferation was determined by Ki67 immunostaining.RESULTS: Treatment with either celecoxib or indomethacin inhibited gastric tumor proliferation by more than 65% (P<0.02). However, celecoxib caused a dose-dependent increase in apoptosis (P<0.05) which was not seen in indomethacin-treated tumors (P = 0.54). The highest apoptosis to proliferation ratio was seen in tumors treated with celecoxib at 10 mg/(kg·d). Treatment with this dose of celecoxib was associated with the lowest incidence of gastric cancer development.CONCLUSION: Our findings suggest that the difference in chemopreventive effects of indomethacin and celecoxib in this animal model of gastric carcinogenesis is largely due to the differential cell kinetic changes, which does not correlate with the degree of COX-2 and PG suppression. 展开更多
关键词 Stomach cancer CELECOXIB INDOMETHACIN Cell kinetics
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Sulfur-doped g-C3N4/TiO2 S-scheme heterojunction photocatalyst for Congo Red photodegradation 被引量:39
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作者 Juan Wang Guohong Wang +2 位作者 Bei Cheng Jiaguo Yu Jiajie Fan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第1期56-68,共13页
Constructing step-scheme(S-scheme)heterojunctions has been confirmed as a promising strategy for enhancing the photocatalytic activity of composite materials.In this work,a series of sulfur-doped g-C3N4(SCN)/TiO2 S-sc... Constructing step-scheme(S-scheme)heterojunctions has been confirmed as a promising strategy for enhancing the photocatalytic activity of composite materials.In this work,a series of sulfur-doped g-C3N4(SCN)/TiO2 S-scheme photocatalysts were synthesized using electrospinning and calcination methods.The as-prepared SCN/TiO2 composites showed superior photocatalytic performance than pure TiO2 and SCN in the photocatalytic degradation of Congo Red(CR)aqueous solution.The significant enhancement in photocatalytic activity benefited not only from the 1D well-distributed nanostructure,but also from the S-scheme heterojunction.Furthermore,the XPS analyses and DFT calculations demonstrated that electrons were transferred from SCN to TiO2 across the interface of the SCN/TiO2 composites.The built-in electric field,band edge bending,and Coulomb interaction synergistically facilitated the recombination of relatively useless electrons and holes in hybrid when the interface was irradiated by simulated solar light.Therefore,the remaining electrons and holes with higher reducibility and oxidizability endowed the composite with supreme redox ability.These results were adequately verified by radical trapping experiments,ESR tests,and in situ XPS analyses,suggesting that the electron immigration in the photocatalyst followed the S-scheme heterojunction mechanism.This work can enrich our knowledge of the design and fabrication of novel S-scheme heterojunction photocatalysts and provide a promising strategy for solving environmental pollution in the future. 展开更多
关键词 TiO2 nanofiber Sulfur-doped g-C3N4 Step-scheme heterojunction photocatalysis In situ XPS S-scheme mechanism
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Mineralization-related geochemical anomalies derived from stream sediment geochemical data using multifractal analysis in Pangxidong area of Qinzhou-Hangzhou tectonic joint belt, Guangdong Province, China 被引量:5
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作者 张焱 周永章 +8 位作者 王林峰 王正海 何俊国 安燕飞 李红中 曾长育 梁锦 吕文超 高乐 《Journal of Central South University》 SCIE EI CAS 2013年第1期184-192,共9页
Distinguishing geochemical anomalies from background is a basic task in exploratory geochemistry. The derivation of geochemical anomalies from stream sediment geochemical data and the decomposition of these anomalies ... Distinguishing geochemical anomalies from background is a basic task in exploratory geochemistry. The derivation of geochemical anomalies from stream sediment geochemical data and the decomposition of these anomalies into their component patterns were described. A set of stream sediment geochemical data was obtained for 1 880 km 2 of the Pangxidong area, which is in the southern part of the recently recognized Qinzhou-Hangzhou joint tectonic belt. This belt crosses southern China and tends to the northwest (NE) direction. The total number of collected samples was 7 236, and the concentrations of Ag, Au, Cu, As, Pb and Zn were measured for each sample. The spatial combination distribution law of geochemical elements and principal component analysis (PCA) were used to construct combination models for the identification of combinations of geochemical anomalies. Spectrum-area (S-A) fractal modeling was used to strengthen weak anomalies and separate them from the background. Composite anomaly modeling was combined with fractal filtering techniques to process and analyze the geochemical data. The raster maps of Au, Ag, Cu, As, Pb and Zn were obtained by the multifractal inverse distance weighted (MIDW) method. PCA was used to combine the Au, Ag, Cu, As, Pb, and Zn concentration values. The S-A fractal method was used to decompose the first component pattern achieved by the PCA. The results show that combination anomalies from a combination of variables coincide with the known mineralization of the study area. Although the combination anomalies cannot reflect local anomalies closely enough, high-anomaly areas indicate good sites for further exploration for unknown deposits. On this basis, anomaly and background separation from combination anomalies using fractal filtering techniques can provide guidance for later work. 展开更多
关键词 geochemical anomalies fractal modeling principal component analysis Qinzhou-Hangzhou joint tectonic belt streamsediments
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Morphological changes and allometric growth in hatcheryreared Chinese loach Paramisgurnus dabryanus(Dabry de Thiersant, 1872) 被引量:11
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作者 张云龙 吴巧婉 +7 位作者 胡伟华 汪帆 邵韦涵 张诚明 赵忠波 何辉 樊启学 顾泽茂 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第4期757-762,共6页
The length-weight relationship and allometric growth patterns of hatchery-reared Chinese loach, Paramisgurnus dabryanus(Dabry de Thiersant, 1872), were determined from hatching to 60 days after hatching. A best power ... The length-weight relationship and allometric growth patterns of hatchery-reared Chinese loach, Paramisgurnus dabryanus(Dabry de Thiersant, 1872), were determined from hatching to 60 days after hatching. A best power model was estimated for the length-weight relationship during the early life stages. Positive allometric growth for the head segment, trunk length, tail length and eye diameter was also found in the early life stages, while body depth, tail depth, tail fi n length, pectoral fi n length and barbel length displayed a negative coeffi cient. During the subsequent early developmental stage, the growth coeffi cients showed a clear and common tendency towards isometry for all measured body ratios. The allometric growth changes in Chinese loach during the early stage are possibly the result of selective organogenesis directed towards survival priorities. 展开更多
关键词 Paramisgurnus dabryanus early life stages length-weight relationship allometric growth
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