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氯沙坦钾的合成工艺研究

广州化工 2022年第4期50卷 40-41页

作者：吴剑郭鹏曾罗生保胡华南九江学院化学化工学院江西九江332005

以2-丁基-4-氯-5-甲酰基-咪唑和2-氰基-4′-溴甲基联苯为原料,依次经过NaBH;还原和四唑化反应得氯沙坦,最后与氢氧化钾成盐得到氯沙坦钾1。本文对氯沙坦钾1合成工艺进行改进,2-丁基-4-氯-5-甲酰基-咪唑和2-氰基-4′-溴甲基联苯的最佳摩... 详细信息

以2-丁基-4-氯-5-甲酰基-咪唑和2-氰基-4′-溴甲基联苯为原料,依次经过NaBH;还原和四唑化反应得氯沙坦,最后与氢氧化钾成盐得到氯沙坦钾1。本文对氯沙坦钾1合成工艺进行改进,2-丁基-4-氯-5-甲酰基-咪唑和2-氰基-4′-溴甲基联苯的最佳摩尔比为1.0:1.1,四唑化反应中叠氮化钠3.0 eq,得到氯沙坦钾1,总收率75.7%。该方法生产工艺简单,操作简便,产品质量稳定,收率高,适合工业化生产。

关键词： 2-丁基-4-氯-5-甲酰基-咪唑 2-氰基-4′-溴甲基联苯氯沙坦钾抗高血压

10,9-硼氧杂菲-10-β-二酮衍生物的合成、性质与结构

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化学学报 1988年第6期46卷 567-571页

作者：单自兴赵德杰邬飞岳张国敏罗保生谌了容武汉大学化学系武汉武汉大学测试中心武汉

10-羟基-10,9-硼氧杂菲与乙酰基丙酮;1-二茂铁基-1,3-丁二酮,苯甲酰基丙酮,二苯甲酰基甲烷和乙酰基乙酰基苯胺在苯中等摩尔反应生成具色双齿螯合物1、2、3、4和无色分子配合物5.

关键词： β-二酮分子离域配合物单晶射线衍射分析晶形配体 IR光谱红外光谱

A keyed-hashing based self-synchronization mechanism for port address hopping communication

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Frontiers of Information Technology & Electronic Engineering 2017年第5期18卷 719-728页

作者： Yue-bin luo bao-sheng WANG Xiao-feng WANG Bo-feng ZHANG College of Computer National University of Defense TechnologyChangsha 410073China

Port address hopping(PAH) communication is a powerful network moving target defense(MTD)mechanism. It was inspired by frequency hopping in wireless communications. One of the critical and difficult issues with PAH is synchronization. Existing schemes usually provide hops for each session lasting only a few seconds/minutes, making them easily influenced by network events such as transmission delays, traffic jams, packet dropouts, reordering, and retransmission. To address these problems, in this paper we propose a novel selfsynchronization scheme, called ‘keyed-hashing based self-synchronization(KHSS)'. The proposed method generates the message authentication code(MAC) based on the hash based MAC(HMAC), which is then further used as the synchronization information for port address encoding and decoding. Providing the PAH communication system with one-packet-one-hopping and invisible message authentication abilities enables both clients and servers to constantly change their identities as well as perform message authentication over unreliable communication mediums without synchronization and authentication information transmissions. Theoretical analysis and simulation and experiment results show that the proposed method is effective in defending against man-in-the-middle(MITM) attacks and network scanning. It significantly outperforms existing schemes in terms of both security and hopping efficiency.

关键词： Synchronization Port address hopping Moving target defense Network security

Control of gallbladder contractions by cholecystokinin through cholecystokinin-A receptors on gallbladder interstitial cells of cajal

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World Journal of Gastroenterology 2008年第18期14卷 2882-2887页

作者： Dan Xu bao-Ping Yu He-sheng luo Ling-Dan Chen Department of Gastroenterology Renmin Hospital of Wuhan University Wuhan 430060 Hubei Province China

AIM: To identify the cholecystokinin (CCK)-A receptors (CCK-AR) on the guniea pig gallbladder interstitial cells of cajal (ICC) and to study CCK-8 induced gallbladder muscle strip contractions through the CCK-AR. METHODS: The existence of CCK-AR was examined by immunohistofluorescence on sectioned tissue and cultured cells. In vitro contractile response of guinea pig gallbladder muscle strips and the strips with ICC removed were also studied with CCK-8 receptors added. RESULTS: In tissue sections, intensely CCKAR- immunoreactive interstitial cells were found mainly in the muscular layers. In cultured cell sections, distinctive double staining of C-kit and CCK-AR ICCs were found. When we removed the ICC of the gallbladder, CCK-8 induced muscle strip contraction dose response curve significantly shifted to the right. CONCLUSION: We proved that both the existence of CCK-AR on the guinea pig gallbladder ICC and CCK evoked contraction are mediated through direct action on CCK-AR on the gallbladder ICC.

关键词： Gallbladder Interstitial cells of cajal Cholecystokinin-A receptor C-kit Immunohistofluorescence

Mullite/Al-4.5Cu复合材料的时效析出行为

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四川大学学报（工程科学版） 2001年第5期33卷 94-97页

作者：龙剑平李伟景山沈保罗高升吉涂铭旌四川大学制造科学与工程学院四川成都610065

选用挤压铸造法制备mullite/Al - 4.5Cu复合材料 ,采用硬度测试 (HB)、差示扫描量热DSC、透射电镜(TEM)等手段研究了mullite/Al- 4.5Cu复合材料的时效特性。结果表明 :莫来石纤维的引入明显提高了基体合金的时效硬度 ,加速了基体合金的... 详细信息

选用挤压铸造法制备mullite/Al - 4.5Cu复合材料 ,采用硬度测试 (HB)、差示扫描量热DSC、透射电镜(TEM)等手段研究了mullite/Al- 4.5Cu复合材料的时效特性。结果表明 :莫来石纤维的引入明显提高了基体合金的时效硬度 ,加速了基体合金的时效硬化速度 ,对GP区的形成有抑制作用 ,但没有改变基体合金的时效析出序列。复合材料具有和基体合金相似的时效硬化曲线。

关键词：铝基复合材料莫来石短纤维 Al-Cu合金时效 Mullite/Al-4.5Cu合金时效析出序列时效硬度

Species identification of poisonous medicinal plant using DNA barcoding

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Chinese Journal of Natural Medicines 2019年第8期17卷 585-590页

作者： LIU Miao LI Xi-Wen LIAO bao-sheng luo Lu REN Yue-Ying College of Chinese Medicine Materials Jilin Agriculture University Changchun 130118 China Institute of Chinese Materia Medica Academy of Chinese Medical Sciences Beijing 100700 China

The aim is to select a universal DNA barcode for identifying all poisonous medicinal plants in Chinese pharmacopoeia and their poisonous related species or adulterants. We chose 4 commonly used regions as candidate DNA barcodes(ITS2, psb A-trn H,matK and rbc L) and compared their identification efficiency in 106 species from 27 families and 65 genera totally. Data analysis was performed including the information of sequence alignment, inter/intra-specific genetic distance and data distribution, identification efficiency and the situation of Neighbor-Joining(NJ) phylogenetic trees. We found ITS2 sequence region had high variation, stable genetic distance and identification efficiency relatively. The topological structure of NJ phylogenetic tree showed monophyletic. Our findings show that ITS2 can be applied as a universal barcode for identifying poisonous medicinal plants in Chinese pharmacopoeia and their poisonous related species or adulterants.

关键词： Sequence Poisonous herbal medicine Genetic distance DNA barcoding ITS2 Blast

Fabrication of green one-part geopolymer from silica-rich vanadium tailing via thermal activation and modification

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International Journal of Minerals,Metallurgy and Materials 2022年第1期29卷 177-184页

作者： Shenxu bao Yongpeng luo Yimin Zhang Hubei Key Laboratory of Mineral Resources Processing and Environment Wuhan University of TechnologyWuhan 430070China School of Resources and Environmental Engineering Wuhan University of TechnologyWuhan 430070China State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution Control Wuhan University of Science and TechnologyWuhan 430081China Hubei Collaborative Innovation Center for High Efficient Utilization of Vanadium Resources Wuhan University of Science and TechnologyWuhan 430081China

The aim of this investigation was to prepare geopolymeric precursor from vanadium tailing(VT)by thermal activation and *** activation,a homogeneous blend of VT and sodium hydroxide was calcinated at an elevated temperature and then modified with metakaolin to produce a geopolymeric *** the thermal activation,the VT was corroded by sodium hydroxide and then sodium silicate formed on the particle *** water was added,the sodium silicate coating dissolved to release silicon species,which created an alkaline solution *** metakaolin then dissolved in the alkaline environment to generate aluminum species,which was followed by *** VT particles were connected by a gel produced during geopolymerization,which yielded a geopolymer with excellent mechanical *** investigation not only improves the feasibility of using geopolymer technology for large-scale and in-situ applications,but also promotes the utilization of VT and other silica-rich solid wastes.

关键词： vanadium tailing thermal activation geopolymeric precursor compressive strength leaching behavior

Quantitative Relationship Between Multi-Angle Polarized Reflectance and BRDF of Rock

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Journal of China University of Mining and Technology 2005年第3期15卷 192-196页

作者： ZHAO Yun-sheng WU Tai-xia LIU bao luo Yang-jie College of Urban and Environmental Sciences Northeast Normal University Changchun Jilin 130024 China Foreign Languages Institute Northeast Normal University Changchun Jilin 130024 China

The traditional remote sensing mainly detects the ground vertically to obtain the 2D information but it is hard to get adequate parameters for the quantitative remote sensing to invert land features. The multi-angle observation can get more detailed and reliable 3D structural parameters of targets, so it makes the quantitative remote sensing applicable. During the process of reflecting, scattering and transmitting the electromagnetic wave, minerals and rocks could reveal the polarized features related to the nature of themselves. Therefore, it has become a new approach of quantitative remote sensing to detect multi-angle polarized information of minerals and rocks. In respect that the polarized reflectance always goes with the bidirectional one, we can obtain the 3D spatial distribution of targets by a polarized means together with detecting its bi-directional reflectance. From the perspective of multi-angle polarized remote sensing mechanism, the quantitative relationship between multi-angle polarized reflectance and the BRDF is studied in this paper. And it is testified that the bi-directional reflectance, polarized reflectance of 45° and the mean value of polarized reflectance are equal to that of the corresponding azimuth angle, zenith angle, detection angle and detection channels in 27t space by experiment.

关键词： Rock Multi-angle Polarized reflectance BRDF Quantitative remote sensing

Reactive oxygen species metabolism during the cadmium hyperaccumulation of a new hyperaccumulator Sedum alfredii (Crassulaceae)

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Journal of Environmental Sciences 2007年第11期19卷 1311-1317页

作者： ZHANG Zhong-chun QIU bao-sheng College of Life Sciences Huazhong Normal University Wuhan 430079 China

Sedum alfredii Hance, a newly discovered hyperaccumulator, could serve as a good material for phytoremediation of Cd polluted sites. Malondialdehyde （MDA）, reactive oxygen species （ROS） and antioxidases （catalase （CAT）; superoxide dismutase （SOD）; peroxidase （POD）） in the leaf were determined when S. alfredii was treated for 15 d with various CdC12 concentrations ranging from 0 to 800 μmol/L. The results showed that the production rate of 2＇,7＇-dichlorofluorescein （DCF）, which is an indicator of ROS level, reached up to the maximum at 400 μmol/L CdCl2 and then declined with the increase of CdCl2 concentration, while MDA accumulation tended to increase. CAT activity was significantly inhibited at all tested CdCl2 concentrations and SOD activity was sharply suppressed at 800 μmol/L CdCl2. However, the enhancement of POD activity was observed when CdCl2 concentration was higher than 400 μmol/L. In addition, its activity increased when treated with 600 μmol/L CdCl2 for more than 5 d. When sodium benzoate, a free radical scavenger, was added, S. alfredii was a little more sensitive to Cd toxicity than that exposed to Cd alone, and the Cd accumulation tended to decline with the increase of sodium benzoate concentration. It came to the conclusions that POD played an important role during Cd hyperaccumulation, and the accumulation of ROS induced by Cd treatment might be involved in Cd hyperaccumulation.

关键词： cadmium hyperaccumulation reactive oxygen species Sedum alfredii