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Effects of benactyzine on action potentials and contractile force of guinea pig papillary muscles

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郑州大学学报(医学版) 2000年第2期35卷 124-127页

作者： DING Zhongren 1)△ , ZHANG Yan 2. , ZHANG Guiqing 2. , KE Jun 2. , HU Xiangjie 2. 1)Department of Hematology,Peking Union Medical Hospital,Chinese Academy of Medical Sciences,beijing 10073. 2.Department of Pharmacology, Henan Medica Department of Hematology Peking Union Medical HospitalChinese Academy of Medical SciencesBeijing 100730 Department of Pharmacology Henan Medical UniversityZhengzhou 450052

Aim: To explore the effects of benactyzine (BEN) on the action potential and contractile force in guinea pig papillary muscles. Methods: Conventional microelectrode technique was used to record the fast action potentials (FAP) and slow action potentials (SAP) of guinea pig papillary muscles. Results: Benactyzine 5, 10, 50 μmol·L -1 suppressed the maximal upstroke velocity ( v max ) of FAP and contractile force (Fc) concentration dependently while prolonged the action potential duration at 50%, 90% repolarization (APD 50 , APD 90 ) and effective refractory period (ERP) of FAP. The suppression on the v max was frequency dependent. Benactyzine 5, 10,50 μmol·L -1 lengthened the APD50, APD90 of SAP induced by isoprenaline or histamine when perfused with KCl 2. mmol·L -1 Tyrode’s solution. The v max of the SAP was not decreased by benactyzine 5, 10 μmol·L -1 but by 50 μmol·L -1 . The effects on the SAP were antagonized by elevation of the extracellular calcium from 2.0 to 5.6 mmol·L -1 . The effects of benactyzine on SAP elicited by tetrodotoxin resembled that by isoprenaline or histamine except the more pronounced suppression on v max and action potential amplitude (APA). The persistent rapid spontaneous activity and triggered tachyarrhythmia induced by ouabain were also abolished immediately by benactyzine 5 μmol·L -1 . Conclusion: Benactyzine can inhibit Na +, K +, Ca 2. transmembrane movement and intracellular Ca 2. mobilization in the myocardium, and this may be the electrophysiological basis of its effects against experimental arrhythmias.

关键词： benactyzine papillary muscle action potential myocardial contraction tetrodotoxin

Effect of Heat Treatment on Crystallization of Nd:YAG Ceramics

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Journal of Wuhan University of Technology(Materials Science) 2007年第2期22卷 333-336页

作者：张华山苏春辉 School of Materials and Chemical Engineering Changchun University of Science and Technology

（Nd0.01Y0.99）3.l5O12.nano-sized powders were synthesized by low temperature combustion （LCS）, using Nd2.3. Y2.3. Al（NO3.3.9H2., ammonia water and citric acid as starting materials. The powders were characterized by TG-DTA, XRD, FT-IR, ICP and TEM, respectively. The grain sizes were calculated by the Scherrer＇s formula using the full width at half maximum （FWHM） of YAG （42.） crystal plane diffraction lines. The study focused on crystallization of ceramics at different heat treatment temperatures. The experimental results show that crystallizing temperature of YAG is 850 ℃, and the intermediate crystal phase YAP, appearing during heat treatment, transforms to YAG cubic crystal phase at the temperature of 1 050℃. The particle size of the powders synthesized by LCS is nano-sized. With the temperature increasing, the mean grain sizes raise, the stand deviations keep almost at the value of 2.0 and the lattice parameters decrease. The grains mainly grow by grain boundary diffusion. The lattice parameter expansion is caused by an increase of the repulsive dipolar interactions on surfaces of crystallites,

关键词： laser ceramics neodymium-doped yttrium aluminum garnet (Nd:YAG) nano-sized powders low temperature combustion synthesis (LCS)

On the major proposals for carbon emission reduction and some related issues

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Science China Earth Sciences 2010年第12期53卷 159-172页

作者： DING ZhongLi1,DUAN XiaoNan2.GE QuanSheng3.& ZHANG ZhiQiang4 1 CAS Key Lab of Cenozoic Geology and Environment,Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing 10002.,China 2.The General Office of Chinese Academy of Sciences,beijing 100864,China 3.Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,beijing 100101,China 4 The Lanzhou Branch of the National Science Library,Scientific Information Center for Resources and Environment of CAS,Lanzhou 73.000,China 1. CAS Key Lab of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China2. The General Office of Chinese Academy of Sciences Beijing 100864 China3. Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China4. The Lanzhou Branch of the National Science Library Scientific Information Center for Resources and Environment of CAS Lanzhou 730000 China

We evaluated and ran simulations for seven proposals for the reduction of global CO2.emissions (e.g.,those of the Intergovernmental Panel on Climate Change (IPCC),United Nations Development Program,and Organization for Economic Cooperation and Development).All the proposals ignored the fact that the cumulative CO2.emissions per capita for developed countries were 7.54 times those for developing countries in the historical period of *** proposals further deliberately allocate 2.06-2.50 emission quotas to developed countries that are 2.3.6.7 times those to developing *** will seriously violate the development rights of developing *** paper clearly states that proposals such as that of the IPCC are not suitable references for future international climate change negotiations as they violate the fundamentals of fairness and equity in international relationships and the UNFCCC principle of "common but differentiated responsibilities".Comparing estimates of emissions in China in the scenario of rapid development with low-CO2.emission technology in the period 2.06-2.50 with estimates for other countries and groups,we find that China can logically and morally argue for equivalent emission rights even in the case of the strict CO2.concentration target of 450-470 ppmv.

关键词： CO2 emission reduction cumulative CO2 emission per capita emission rights

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稀土元素防治植物病害的研究进展

中国稀土学报 2003年第1期21卷 1-5页

作者：慕康国张福锁王成菊张文吉胡林中国农业大学资源与环境学院北京100094 中国农业大学应用化学学院北京100094

稀土元素在农业上应用的有关研究主要集中在植物生理活性、生理生化机制及稀土元素的卫生毒理学和环境安全性方面,对其在防治植物病害、对植物病原微生物方面的研究较少。本文对稀土元素在防治植物病害及诱导植物抗病性方面进行了综述,... 详细信息

稀土元素在农业上应用的有关研究主要集中在植物生理活性、生理生化机制及稀土元素的卫生毒理学和环境安全性方面,对其在防治植物病害、对植物病原微生物方面的研究较少。本文对稀土元素在防治植物病害及诱导植物抗病性方面进行了综述,重点探讨了稀土元素防治植物病害的作用机制,并展望了此方面的应用前景,期望能够对于进一步研究利用稀土防治植物病害,拓宽稀土元素农用范围发挥一定的指导作用。

关键词：植物学植物病害综述作用机制稀土

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东营凹陷南部樊东地区隐蔽圈闭研究

特种油气藏 2004年第4期11卷 23-25页

作者：杨飞王英民金武弟李群石油大学盆地与油藏研究中心教育部石油天然气成藏机理重点实验室北京102249

樊东地区位于东营凹陷南部缓坡带 ,是各类砂体发育的有利地带。由于其砂层较薄 ,虽能在测井曲线上很好地显示 ,但在地震剖面上难以识别与追踪。为此 ,提出测井 -地震体反演-地质解释三位一体的隐蔽圈闭研究方法 ,即利用测井研究砂层的... 详细信息

樊东地区位于东营凹陷南部缓坡带 ,是各类砂体发育的有利地带。由于其砂层较薄 ,虽能在测井曲线上很好地显示 ,但在地震剖面上难以识别与追踪。为此 ,提出测井 -地震体反演-地质解释三位一体的隐蔽圈闭研究方法 ,即利用测井研究砂层的地球物理响应特征 ,确定砂层及其盖层与波阻抗值的对应关系 ,然后在稀疏脉冲反演获得的地震波阻抗属性体上进行砂体的识别与追踪 ,并在此基础上。

关键词：隐蔽圈闭油气地质测井地震体反演地质解释东营凹陷

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面元叠加地震采集技术

石油物探 2003年第2期42卷 160-168页

作者：谭绍泉刘光林刘泰生胡立新徐淑合中国地质大学北京100083 中国石化胜利油田物探公司山东东营257100

面元叠加地震采集技术是为适应资料处理的要求而提出的一种采集方法 ,也是适应目标采集和目标处理的一种观测方式 ,它对解决深层和复杂地区的地震勘探技术是有效的。通过对面元叠加的基本原理、技术特点的论述和 4个地区应用效果的对比。

关键词：面元叠加地震采集技术目标采集目标处理地震勘探技术基本原理技术特点

Anisotropic characteristic in HDDR Nd_(13.Fe_(80)B_7

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Journal of University of Science and Technology beijing 2003年第3期10卷 26-29页

作者： Jingzhi Han, Aizhi Sun, Yaofu Xiao, Xubo Liu, and Run WangMaterials Science and Engineering School, University of Science and Technology beijing, beijing {2. China Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China

The function of disproportionation and desorption stages ofhydrogenation-disproportionation-desorption-recombination (HDDR) process in the formation ofmagnetic anisotropy was studied. The results showed that degree of anisotropy (DOA) ofNd_(13.Fe_(80)B_7 induced by appropriate HDDR process is comparable with that ofNd_(13.Fe_(80-x)B_7M_x (M=Co, Zr or Ga), however, the moderate coercive force of Nd_(13.Fe_(80)B_7magnetic powder led to an undesirable (BH)_(max) of 104 kJ/m^3.in bonded magnet. Experimentsdemonstrated that a relatively short disproportionation time, combined with a high desorptiontemperature and slow desorption rate, during HDDR process is beneficial to anisotropy attainment,but HDDR Nd_(13.Fe_(80)B_7 magnetic powder becomes isotropic if the disproportionation time islonger than a certain period. This phenomenon strongly indicated that the origin of anisotropy inNdFeB-type HDDR material is contributed by disproportionation stage. XRD (X-ray Diffraction)analysis and TEM (Transmission Electron Microscope) observation told that no other phase exceptNdH_2. alpha-Fe and Fe_2. has been found in the disproportionation step. The formation of HDDRNd_(13.Fe_(80)B_7 anisotropy might be related to the early lamella disproportionation structure.

关键词： HDDR anisotropy isotropy NdFeB

镧对Rhizoctonia solani的毒力及其致病酶活性的影响

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中国稀土学报 2004年第1期22卷 149-152页

作者：慕康国张福锁胡林张文吉中国农业大学资源环境学院北京100094 中国农业大学应用化学学院北京100094

采用琼脂平板生长速率法及液体培养基培养测定了La对立枯丝核病菌(Rhizoctoniasolani)的抑制作用和毒力,并测定了其对病菌胞外的果胶酶、蛋白酶和纤维素酶等几种致病酶的活性的影响。结果表明,随着La浓度升高,对病菌菌丝生长的抑制作用... 详细信息

采用琼脂平板生长速率法及液体培养基培养测定了La对立枯丝核病菌(Rhizoctoniasolani)的抑制作用和毒力,并测定了其对病菌胞外的果胶酶、蛋白酶和纤维素酶等几种致病酶的活性的影响。结果表明,随着La浓度升高,对病菌菌丝生长的抑制作用增强,固体培养上所测定的对病菌的EC50和EC95分别为171.9和667.7mg·L-1;在液体培养基中所测定的EC50和EC95分别为111 4和500 7mg·L-1。在一定浓度范围内,La提高了单位量菌丝所产生3.致病酶的活性,但由于对菌丝生长量的强烈抑制,使病菌胞外3.致病酶的总量或总活性受到抑制,减低了病菌的致病力。

关键词：镧 Rhizoctonia solani 毒力致病酶活性稀土

Distribution of Nb atom in the TiAl+Nb system

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Rare Metals 2001年第1期20卷 5-12页

作者： Xiaodong Ni, Xidong Hui, Guoliang Chen (Applied Science School, University of Science and Technology beijing, beijing {2. China State Key Laboratory for Advanced Metals and Materials, University of Science and Technology beijing, China) Appl. Sci. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Based on MEAM (the modified embedded atom method) potential and an average atom model similar to B-W (Bragg-Williams) method, the distribution of Nb atoms in TiAl+Nb compounds with various composition was calculated. The calculation results showed that Nb atoms prefer to occupy the Ti sublattice of L10 structure for all compounds in question. With increasing atomic fraction of Nb and Al, Nb atoms exhibited a trend of ordered distribution on the Ti sublattice and result in a new L10 derivative superlattice structure.

关键词： Computer simulation Intermetallics Superlattices Ternary systems