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Studies on the Automated Determination of Total Rare Earths in Al-Re Alloys by Automated Flow Injection Device with DBC-CPA Reagent

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Chemical Research in Chinese Universities 1988年第2期 31-38页

作者： Chen Danhua, cai Ruxiu and zeng yun’e(Department of Chemistry, Wuhan University, Wuchang)

The automatic determination of the total rare earths in the aluminium-rare earth alloys was studied by using our recently designed automated flow injection device and the high sensitive and selective rare earth reagent-DBC-CPA (2 -(2-phosphono-4-chlorophen-ylazo)-7-(2,,6-dibromo-4-chlorophenylazo)-1,8-dihydroxy-3, 6 - dis-ulfonaphthalene). The automated flow injection device consists of an Apple Ⅱ microcomputer, two peristaltic pumps and a spectrophoto-meter. It has good automatic degree and high producibility, the sampling volume and rotation velocity of the pumps can be changed continuously and automatically. The total rare earths in aluminium-rare earth alloys were automatically determined at 645nm wavelength in the medium of ***/L HC1 and 1% H2C2O4 . Fe Cu, Al, Mg, Ni, Zn and Cr don’t interfere with the determination and temperature has no effect on the sensitivity in the range of 10-49℃ above zero. The calibration curves for cerium group and yttrium group rare earths are close to each other. T

关键词： Flow injection analysis automatic determination DBC-chlorophenylazo Aluminium alloy Rare earths Microcomputer.

Synthesis of Fluoro-Contained Bisazo Chromotropic Acid Derivants and studies on Their Color Reactions with Rare Earth Elements

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Chemical Journal of Chinese Universities 1988年第1期 23-29页

作者： Yang Yi, Yu Ximao, cai Ruxiou, zeng yun’e (Department of Chemistry, Wuhan University, Wuhan)

In this paper, a series of f1uoro-contained bisazo chromotropic acid derivants has been designed and synthesized. They are easily soluble in water, alcohol and acetone but insoluble in benzene, ether and chloroform. Some regularities of the effects of their molecular structure on the color reaction have also been studied. The result shows that in this series of reagents, DCF-chlorophosphonazo and DBF-chlorophosphonazo are excellent color reagents for the determination of the total amount of rare earth elements. The molar absor-ptivities of light and heavy rare earth elements are approach to each other. The tolerant quantity of Bi (Ⅲ) and Pb (Ⅱ) , Sn(Ⅳ) are larger than that of the other arsenazo or chlorophosphonazo type of color reagents. We also discover that p-fluorochlorophosphonazo can form β-type complexes with heavy rare earth elements, and p -fluoro-carboxyazo with light rare earth elements. If the reaction time is controlled, p -fluoro-carboxyao can form β-type complex only with La, and the

关键词： Synthesis of Fluoro-Contained Bisazo Chromotropic Acid Derivants and studies on Their Color Reactions with Rare Earth Elements

速差动力分析法同时测定镨、铒混合物中单一稀土

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分析化学 1989年第8期17卷 743-745页

作者：王丽莎蔡汝秀曾云鹗武汉大学化研系

稀土元素与DBC[2-（2-肺酸基苯偶氮）-7-（2,6-二溴-4-氯苯偶氮）-1,8-二羟基-3,6-二磺酸萘,简称DBC或DBC偶氮胂]反应速率常数随着原子序数的增大而减小,所以Pr、Er之间速率常数差别大。在0.24mol/L HCl介质中Pr与DBC一混合反应即达到平... 详细信息

稀土元素与DBC[2-（2-肺酸基苯偶氮）-7-（2,6-二溴-4-氯苯偶氮）-1,8-二羟基-3,6-二磺酸萘,简称DBC或DBC偶氮胂]反应速率常数随着原子序数的增大而减小,所以Pr、Er之间速率常数差别大。在0.24mol/L HCl介质中Pr与DBC一混合反应即达到平衡,而铒与该试剂反应的半衰期为36秒。利用此反应,本文提出用线性外推法同时测定Pr、Er混合物中的单一稀土,推导了测量方程,用线性外推法测量了5个Pr、Er混合物试样,方法准确度约为5％。此方法简便,并不需要进行复杂的计算。

关键词：速差动力学法铒镨稀土

Complete mitochondrial genome of the atlas moth,Attacus atlas(Lepidoptera:Saturniidae) and the phylogenetic relationship of Saturniidae species

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Complete mitochondrial genome of the atlas moth,Attacus atla...

中国蚕学会第九届青年学术研讨会

作者： Miao-Miao Chen Yan Li Mo Chen Huan Wang Qun Li Run-Xi Xia cai-yun zeng Yu-Ping Li 刘彦群 Li Qin Insect Resource Center for Engineering and Technology of Liaoning Province Shenyang Agricultural University Administration Bureau of Xishuangbanna National Nature Reserve Key Laboratory of Wild Silkworms of Liaoning Province Sericultural Institute of Liaoning Province

Mitochondrial genome(mitogenome) can provide information for genomic structure as well as for phylogenetic analysis and evolutionary *** this study,we present the complete mitogenome of the atlas moth,Attacus atlas(Lepidoptera:Saturniidae),a well-known silk-producing and ornamental insect with the largest wing surface area of all *** mitogenome of *** is a circular molecule of 15,282 bp long,and its nucleotide composition shows heavily biased towards As and Ts,accounting for 79.30%.This genome comprises 13 protein-coding genes(PCGs),two ribosomal RNA genes(rRNAs),22 transfer RNA genes(tRNAs),and an A+T-rich *** is of note that this genome exhibits a slightly positive AT skew,which is different from the other known Saturniidae *** PCGs are initiated by ATN codons,except for COI with CGA *** six PCGs use a common stop codon of TAA or TAG,whereas the remaining seven use an incomplete termination codon T or *** tRNAs have the typical clover-leaf structure,with an exception for tRNA(AGN).The *** A+T-rich region contains non-repetitive sequences,but harbors several features common to the Bombycoidea *** phylogenetic relationships based on Maximum Likelihood method provide a well-supported outline of Saturniidae,which is in accordance with the traditional morphological classification and recent molecular works.

关键词： Atlas moth Attacus atlas Nucleotide composition Genomic structure Phylogenetic relationship

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钐钆富集物中钐、钆的同时测定

高等学校化学学报 1989年第6期10卷 586-590页

作者：王丽莎蔡汝秀曾云鹗华中理工大学化学系武汉大学化学系

本文初步探讨了稀土的DBC偶氮胂络合物与CyDTA取代反应机理。对于不同显色剂和取代剂进行了选择,建立了测量钐、钆的最佳反应体系。用速差动力分析法进行了钐钆富集物中钐、钆的同时测定。速差动力分析结果与ICP发射光谱法结果相符。本... 详细信息

本文初步探讨了稀土的DBC偶氮胂络合物与CyDTA取代反应机理。对于不同显色剂和取代剂进行了选择,建立了测量钐、钆的最佳反应体系。用速差动力分析法进行了钐钆富集物中钐、钆的同时测定。速差动力分析结果与ICP发射光谱法结果相符。本法测定钐、钆相对含量在1:2～4:1范围,误差约为10％。

关键词：钐钆同时测定速差动力学测定 CyDTA 光度法 DBC偶氮络合物

Brain region-specific roles of brain-derived neurotrophic factor in social stress-induced depressive-like behavior

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Neural Regeneration Research 2025年第1期20卷 159-173页

作者： Man Han Deyang zeng Wei Tan Xingxing Chen Shuyuan Bai Qiong Wu Yushan Chen Zhen Wei Yufei Mei Yan zeng Brain Science and Advanced Technology Institute Wuhan University of Science and TechnologyWuhanHubei ProvinceChina Geriatric Hospital Affiliated to Wuhan University of Science and Technology WuhanHubei ProvinceChina School of Public Health Wuhan University of Science and TechnologyWuhanHubei ProvinceChina

Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral *** studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and *** how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress *** this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of *** focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine *** determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic ***,BDNF might be a biological indicator regulating stress-related processes in various brain regions.

关键词： amygdala chronic mild stress chronic social defeat stress corticolimbic system depression hippocampus medial prefrontal cortex nucleus accumbens social stress models ventral tegmental area

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十水草酸镧的热分解及其动力学分析

材料与冶金学报 2017年第2期16卷 116-123页

作者：邓庚凤姬传红谢耀谭敏蔡晨龙王赟曾青云江西理工大学冶金与化学工程学院江西赣州341000

用热重-差热(TG-DTA)技术,在不同升温速率条件下,研究了十水草酸镧在空气气氛下的热分解过程.分别采用Ozawa-Flynm-Wall法、Kissinger法、Crane法和同步热分析法确定其热分解动力学参数.TG-DTA曲线表明:十水草酸镧分解为四个阶段,前两... 详细信息

用热重-差热(TG-DTA)技术,在不同升温速率条件下,研究了十水草酸镧在空气气氛下的热分解过程.分别采用Ozawa-Flynm-Wall法、Kissinger法、Crane法和同步热分析法确定其热分解动力学参数.TG-DTA曲线表明:十水草酸镧分解为四个阶段,前两个阶段为脱水过程,后两个阶段为La_2(C_2O_4)_3的分解过程.实验计算得出四步反应表观活化能E分别为83.92、76.04、136.26、162.61 k J·mol-1左右;指前因子A分别为4.92×10^(10)、6.1×10~7、2.1×10~9、8.46×10~6s-1左右;反应级数n均为1左右,并用Coats-Redfem积分法得出第三步分解机理受F1控制.

关键词： G-DTA La2(C2O4)3·10H2O 热分解动力学参数

DBC-偶氮胂与稀土元素在高酸度下显色反应的研究(Ⅱ)——DBC-偶氮胂的萃取提纯与鉴定

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化学试剂 1986年第5期 266-269页

作者：李红蔡汝秀曾云鹗武汉大学化学系

DBC-偶氮肿,全称3-(2-胂酸基苯偶氮-6-(2,6)-二溴-4-氯苯偶氮)-4,5-二羟基-2,7-萘二磺酸,是武汉大学分析研究室新合成的稀土显色剂。此试剂与其它变色酸双偶氮衍生物相比可在更强的酸性溶液中(0.2～1.7NHCl)与稀土发生显色反应。其选择... 详细信息

DBC-偶氮肿,全称3-(2-胂酸基苯偶氮-6-(2,6)-二溴-4-氯苯偶氮)-4,5-二羟基-2,7-萘二磺酸,是武汉大学分析研究室新合成的稀土显色剂。此试剂与其它变色酸双偶氮衍生物相比可在更强的酸性溶液中(0.2～1.7NHCl)与稀土发生显色反应。其选择性很高,且对成分复杂的高温合金可不经分离直接进行测定。

关键词： DBC 高酸度偶氮胂偶氮化合物萃取提纯显色反应点滴试验稀土元素 ⅢB族元素

Glucocorticoid receptor signaling in the brain and its involvement in cognitive function

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Neural Regeneration Research 2025年第9期20卷 2520-2537页

作者： Chonglin Su Taiqi Huang Meiyu Zhang Yanyu Zhang Yan zeng Xingxing Chen Brain Science and Advanced Technology Institute Hubei Province Key Laboratory of Occupational Hazard Identification and ControlSchool of MedicineWuhan University of Science and TechnologyWuhanHubei ProvinceChina

The hypothalamic-pituitary-adrenal axis regulates the secretion of glucoco rticoids in response to environmental *** the brain,a nuclear receptor transcription fa ctor,the glucocorticoid recepto r,is an important component of the hypothalamicpituitary-a d renal axis's negative feedback loop and plays a key role in regulating cognitive equilibrium and *** glucoco rticoid receptor influences cognitive processes,including glutamate neurotransmission,calcium signaling,and the activation of brain-derived neurotrophic factor-mediated pathways,through a combination of genomic and non-genomic *** interactions within the central nervous system can alter the expression and activity of the glucocorticoid receptor,there by affecting the hypothalamic-pituitary-a d renal axis and stress-related cognitive *** appropriate level of glucocorticoid receptor expression can improve cognitive function,while excessive glucocorticoid receptors or long-term exposure to glucoco rticoids may lead to cognitive *** with cognitive impairment-associated diseases,such as Alzheimer's disease,aging,depression,Parkinson's disease,Huntington's disease,stroke,and addiction,often present with dysregulation of the hypothalamic-pituitary-adrenal axis and glucocorticoid receptor *** review provides a comprehensive overview of the functions of the glucoco rticoid receptor in the hypothalamic-pituitary-a d renal axis and cognitive *** emphasizes that appropriate glucocorticoid receptor signaling fa cilitates learning and memory,while its dysregulation can lead to cognitive *** provides clues about how glucocorticoid receptor signaling can be targeted to ove rcome cognitive disability-related disorders.

关键词： brain-derived neurotrophic factor calcium signaling glucocorticoid receptor glucocorticoid glutamate transmission hypothalamic-pituitary-adrenal axis long-term potentiation neurocognitive disorders neuroplasticity stress