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1.
以丁酮、乙二胺合成四乙基二甲基四氮杂大环席夫碱化合物,将其还原成四氮杂大环冠醚配体,然后再和高氯酸钴反应生成四氮杂大环冠醚配合物{Et4Me2[14]N4Co}·2C1O4,并用元素分析、红外光谱等手段时其结构进行了表征. 相似文献
2.
目的：研究四氮杂冠醚铜配合物对免疫功能低下小鼠碳粒廓清水平的影响。方法：腹腔注射（ip）CTX制备小鼠免疫抑制模型,同时灌胃（ig）给药8d,采用分光光度法测定免疫功能低下小鼠碳粒廓清水平,观察四氮杂冠醚铜配合物对非特异性免疫功能的影响。结果：四氮杂冠醚铜配合物显著提高免疫抑制小鼠的碳粒廓清水平（P〈0．01）。 相似文献
3.
本文从杂氮硅三环化合物的特殊结构，论述了杂氮硅三环四个方面的生物活性，说明这类化合物在医药、农业等领域具有广泛的应用前景。并介绍了最新研究动向及本人的实验研究部分成果。 相似文献
4.
以1,4,7,10-四氮杂环十二烷(Cyclen)为原料合成了一种新型四氮杂大环化合物,目标化合物经1HNMR、质谱、元素分析等表征. 相似文献
5.
以1,4,7,10-四氮杂环十二烷（Cyclen）为原料合成了一种新型四氮杂大环化合物,目标化合物经^1H NMR、质谱、元素分析等表征． 相似文献
6.
四氮杂大环配合物催化的振荡反应引起了人们的广泛兴趣,这是因为此振荡反应更接近于生物振荡体系。选择了一种四氮杂大环铜配合物催化的化学振荡体系：NaBrO3-苹果酸-H2SO4[CuL]（ClO4）2,其中L为5,7,7,12,14,14-六甲基-1,4,8,11,-四氮环杂十四-4,11-二烯,研究了左旋多巴对该振荡体系的影响。结果表明,左旋多巴的加入明显改变了振荡体系的周期和振幅．且浓度与振幅的改变值△A呈现良好的线性关系,线性范围为：9．90×10^-6-2．44×10^-4,相关系数为0．9933。同时对加入左旋多巴后体系的反应机理进行了初步探讨． 相似文献
7.
研究了四(1,4-二噻英)四氮杂卟啉铁修饰玻碳电极的制备,并用于抗坏血酸(AA)的测定。在pH=6.5的磷酸盐缓冲溶液中,AA在四(1,4-二噻英)四氮杂卟啉铁修饰玻碳电极上产生一灵敏的氧化峰,峰电流与AA的浓度在5.0×10-6～3.0×10-4mol/L范围内呈良好的线性关系,检出限为1.3×10-6mol/L。该电极灵敏度、重现性和稳定性都较为良好。 相似文献
8.
合成了3-氨基-1,3,4,5-四氢-2H-1-苯并氮杂卓-2-酮的消旋体,对所合成到的消旋体化合物进行了手性拆分实验研究,找到了以焦谷氨酸为手性拆分结晶试剂,5-硝基水杨醛为不对称结晶诱导催化剂,乙醇-水溶液为溶剂的实验条件.反应条件温和,所得手性化合物的光学纯度高,其中R（＋）-3-氨基-1,3,4,5-四氢-2H-1-苯并氮杂卓-2-酮的拆分收率为74%,[!]D＋446＂（c=1.0,CH3OH）;S（-）-3-氨基-1,3,4,5-四氢-2H-1-苯并氮杂卓-2-酮的拆分收率为71%,[!]D-443＂（c=1.0,CH3OH）. 相似文献
9.
10.
宁佐芳 《第二课堂(小学)》2004,(3)
............……‘自..............----....……户.*:一、化合价口诀一价钾钠氛氮银,二价氧钙顿俊锌,三铭四硅五价磷;二三铁,二四破,二四六珑都齐全,铜汞二价最常见。二、溶解性口诀钾钠按盐溶水快,①硫酸盐除去钡铅钙②氛化物不溶氛化银,梢酸盆溶液都透明。③口诀中未有皆下沉。④三、1一20号元素顺序口诀⑤氮截枉被翎,谈氮氧氛氛;钠袄铭硅磷,硫氛氮钾钙。四、金属活动性口诀钾钙钠镁铝,锌铁锡铅氮,钢汞银铂金。注洲卫钾钠按盐都溶于水; ②硫酸盐中只有硫酸钡、硫酸铅、硫酸钙不溶; ③峭酸盐都溶于水; ④口诀中没有步及的盐类都不溶于水;… 相似文献
11.
Infant-mother face-to-face interaction: age and gender differences in coordination and the occurrence of miscoordination 总被引：2，自引：0，他引：2
To evaluate the extent to which infants and mothers are able to coordinate their behavior, the interactions of 54 mother-infant pairs--18 each at 3, 6, and 9 months of age--were videotaped. Coordination was evaluated with 2 measures: (1) matching--the extent to which mother and infant engage in the same behavior at the same time; and (2) synchrony--the extent to which mother and infant change their behavior with respect to one another. Mother-infant pairs increase their degree of coordination with infant age, but the proportion of time they are coordinated is small. Mother-son pairs spend more time in coordinated states than mother-daughter pairs. The results suggest that interactions be characterized in terms of their movement from coordinated to miscoordinated states rather than only in terms of their degree of coordination. The gender differences are discussed in terms of their importance for the developmental differences in females and males. 相似文献
12.
基于网络的校际协作学习中,同步交流是其必不可少的一个环节,然而该环节的协作中通常会存在一些不协调的状态。文章首先分析并归纳了校际协作同步交流中的不协调状态,然后提出相应的协调策略,并对实施结果进行分析和总结。 相似文献
13.
徐汉峰 《宁波职业技术学院学报》2011,(4):71-75
贾府非管理人员的会计文化包括贾瑞单思,贾蔷勒据;可卿辞世,薛蟠献棺;赖爷献计,筹建省院;老明公号,一一筹画;贾赦幕控,山野制度;元春省亲,奢华靡费;姨娘迷信,马婆骗财;为官做宰,仕途经济;海棠六钱,送花赏银;熙凤厉害,尤氏挑战;丁丁卯卯,偷偷摸摸;克扣使费,纠缠不清;投机钻营,非法经营;房子加价,邪门歪道;金银财宝,尤如粪土;刀笔先生,许他银子等层面。对中国会计文化建设的贡献在于会计证据。劳动酬金,用好资金,计划控制,规划监督,节约资源,反对迷信,掌握经济,价值规律等方面。 相似文献
14.
Vijay A. Singh 《Resonance》2000,5(8):84-91
The International Physics Olympiad was held in Padua, Italy during July 18–27 1999. It marked India’s second foray into this exciting event where sixty-two nations participated. As the pedagogical leader of the Indian team at Padua, I was privileged to be in the thick of action. Our performance was creditable: all our participants won medals, garnering four silvers and one bronze. Out of the five special prizes, one went to a member of our team. This article describes an interesting and historically rich problem that was posed as part of the five hour theoretical examination. 相似文献
15.
化学是一门实验科学,提高毕业生的实验能力是高校化学教学主要目标之一。近年来,随着产业升级,国内化工企业对高校毕业生的能力有着也来越高的要求。通过对茂名石化公司化验部和研究所的在岗职工工作情况进行调查研究,统计并分析了调查问卷,探讨了在新的形势下,化学实验教学与化工企业人才需求的承接和配合。 相似文献
16.
《南通师范学院学报》2011,(3):23-28
美国学者斯图尔特.帕特里克的失败国家理论研究值得深思。他运用＂能力＂与＂意愿＂双重维度对失败国家理论进行的辨析正名,他同布鲁金斯学会高级研究员苏珊.赖斯（Susan Rice）联袂发布的《2008年第三世界脆弱国家指数》,他对美国严重依赖国防部来解决失败国家问题的批评,他对应对失败国家问题＂全政府＂（whole of government）方略的提倡,均显示了深厚精湛的学识和卓尔不群的理论创造能力。 相似文献
17.
姚忠亮 《宁德师专学报(自然科学版)》2002,14(2):107-110,121
运用电化学循环伏安和石英晶体微天平技术研究了 0 .1mol·L- 1H2 SO4 溶液中甲醇在Pt电极上吸附和氧化行为 .结果表明 ,甲醇的电氧化过程与电极表面氧的吸附物种有着密切的关系 ,并指出甲醇电催化氧化是通过解离吸附产物和反应中间体双途径机理进行的 .电化学原位E QCM进一步从表面质量变化提供了甲醇电催化氧化的新数据 相似文献
18.
曹德光 《重庆大学学报(英文版)》2005,4(2):70-73
1 Introduction 1 During the last decade a new kind of material called geopolymer has emerged as a viable alternative for many conventional cements and plastics. Geopolymer is inorganic polymer derived from metakaolin and sodium silicate solution. It can be synthesized at low temperature and have useful properties such as high compressive strength. It is stable at temperatures up to 800 °C and even 1150 °C while ordinary Portland cement loses its strength at 500 °C [1]. Several microstruct… 相似文献
19.
Ilana A. Manneh Carl-Johan Rundgren Karim M. Hamza Lars Eriksson 《International Journal of Science Education》2013,35(16):2023-2043
ABSTRACTIn this study, we explore the issues and challenges involved in supporting students’ learning to discern relevant and critical aspects of determining oxidation states of atoms in complex molecules. We present a detailed case of an interaction between three students and a tutor during a problem-solving class, using the analytical tool of practical epistemology analysis (PEA). The results show that the ability to make relevant distinctions between the different parts of a molecule for solving the problem, even with the guidance of the tutor, seemed to be challenging for students. These shifts were connected to both purposes that were specific for solving the problem at hand, and additional purposes for general learning of the subject matter, in this case how to assign oxidation states in molecules. The students sometimes could not follow the additional purposes introduced by the tutor, which made the related distinctions more confusing. Our results indicate that in order to provide adequate support and guidance for students the tutor needs to consider how to sequence, move between, and productively connect the different purposes introduced in a tutor-student interaction. One way of doing that is by first pursuing the purposes for solving the problem and then successively introduce additional, more general purposes for developing students’ learning of the subject matter studied. Further recommendations drawn from this study are discussed as well. 相似文献
20.
刘跃发 《石家庄职业技术学院学报》2001,13(4):11-13
讨论了与过渡金属组成配合物对特定反应具有专一催化作用的典型旋光性膦配体的结构,认为当催化剂配体为二元螯合膦、配体磷原子上有环状取代基等关系时,可获得较高的立体选择性. 相似文献