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本文首次采用傅立叶变换红外光谱法，直接、快速、准确地测定彝药鸡根的红外光谱。研究表明：彝药鸡根的不同部位，其红外光谱不同，它们的红外光谱的吸收位置和强度均有明显差异。根据红外特征吸收能够得到鸡根的红外光谱图，从而达到对彝药在分子水平上的研究。该方法具有直接、快速、准确，不破坏样品的原性质；重现性好，仪器相对便宜，方法易掌握，普适性强；可数字化，更具科学性和便于管理；更符合中医中药的医治原则和研究。 相似文献
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本文利用FTIR光谱法分析了野坝子的茎、叶及全草红外光谱图，对红外光谱的峰形进行了归属分析。结果表明：野坝子的茎、叶及全草由于所含的化学成分不同和相对含量的差异，其红外光谱的吸收的位置和强度均有不同，它们具有各自的特征谱，为鉴别野坝子的茎、叶和全草提供了重要依据。 相似文献
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红外光谱法定性分析壳聚糖脱乙酰化度的大小 总被引：1，自引：0，他引：1
该文通过对壳聚糖红外光谱测试结果的分析,比较氨基和乙酰基对远红外光吸收的强弱,论证了红外光谱特征峰的强度可定性地说明壳聚糖脱乙酰化度的大小。 相似文献
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运用傅立叶红外光谱对(胰特敏)和其它几种西药降糖药物进行了指纹图谱分析研究.发现胰特敏和格列本脲红外光谱图有较大的相似性,但是胰特敏和格列齐特、盐酸二甲双胍的指纹图谱有很大的差异存在.综合分析研究后知在胰特敏中可能含有格列本脲.采用此种方法简便可行,无损坏作用且快速,适用性强,可以为该类药物的结构鉴定及质量的监控提供科学依据.实验证明可以用傅立叶红外光谱来初步鉴定中药降糖药物中是否含有两药成分 相似文献
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傅里叶变换红外光谱用于一枝黄花的分析 总被引：1，自引：0，他引：1
分别在室温和在静态空气中升温到600℃的条件下，测定了一枝黄花全草红外光谱图，对红外光谱的峰形进行了归属分析，为鉴别一枝黄花全草提供了重要依据。该方法具有简便、快速、不需对样品分离提取等特点。 相似文献
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《实验技术与管理》2015,(6):37-41
在293K~393K范围内,分别测定聚乙烯甲基弯曲振动模式(δCH 3)的一维红外光谱、二阶导数红外光谱、四阶导数红外光谱和去卷积红外光谱。实验发现:1 455cm-1和1 377cm-1附近的红外吸收峰,分别归属于聚乙烯甲基不对称弯曲振动模式(δas CH 3)和甲基对称弯曲振动模式(δs CH 3)。进一步采用二维红外光谱研究了聚乙烯δCH 3,研究发现:随着测定温度的升高,聚乙烯分子中δCH 3红外吸收强度变化早晚顺序为:1 455cm-1(δas CH 3)早于1 377cm-1(δsCH 3)。此项研究显示出二维红外光谱在高分子材料热变性分析中的重大作用。 相似文献
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红外光谱实验中谱图质量研究 总被引：1，自引：0，他引：1
要想得到一个高质量的红外光谱图,不仅需要掌握光谱的分析方法、样品的制备技术,还要了解样品的特点以及科学的操作技术才能得到满意的结果.该文对红外光谱实验中影响谱图质量的诸多因素进行了详细的探讨. 相似文献
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药物红外谱库的建立与鉴定 总被引：1，自引：0，他引：1
蔡锡兰 《南京晓庄学院学报》1998,(4)
用高纯度的生物检村中提取的药物,在一定的测试条件下测得其红外光谱图,按照一定规则编码,将光谱信息转变为计算机可读形式,存放在计算机存贮设备中建立药物红外光谱库。本实验对常见生物检材中的药物片剂直接进样、检索、解析,确定药物成分。此法操作简便、快速、定性准确。 相似文献
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《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help? 相似文献
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罗艳萍 《读与写:教育教学刊》2008,5(6)
The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity. 相似文献
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《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love. 相似文献
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Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject. 相似文献
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Richard Denner 《海外英语》2007,(4):14-15
Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose. 相似文献
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Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities. 相似文献
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RUZBEHANI Mohsen 《重庆大学学报(英文版)》2004,3(1):20-25
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec… 相似文献