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1.
目的探讨低电压、低浓度碘对比剂联合迭代重建技术在头颈CTA检查的可行性方法选择100例行头颈部CTA检查患者,随机分为低剂量组和对照组。两组对比剂注射速率均为5.0ml/s,注射对比剂量=1.0ml/kg×体重,注射完后均采用30ml生理盐水冲洗。低剂量组管电压100KVP,管电流200mA,使用威视派克(270mgI/ml)对比剂,使用迭代重建(iDose4)算法,对照组管电压120 KVP,管电流200mA,使用碘佛醇(320mgI/ml)对比剂和滤波反射投影算法(FBP)重建;对各组图像质量进行评分并记录每例患者接受的辐射剂量及碘摄入量,对测量结果进行统计学分析。结果双组图像质量都可以满足诊断要求,图像质量评分差异无统计学意义(P>0.05),颈部血管CT值、信噪比(SNR)、对比噪声比(CNR)、双低组剂量长度乘积(DLP)、碘摄入量差异有统计学意义(P<0.05)。结论应用100KV、低浓度对比剂及迭代重建(iDose4)算法进行头颈部CTA扫描,在不影响图像质量前提下可以大幅度减少患者辐射剂量和对比剂碘摄入量。  相似文献   

2.
目的探讨低电压、低浓度碘对比剂联合迭代重建技术在头颈CTA检查的可行性方法选择100例行头颈部CTA检查患者,随机分为低剂量组和对照组。两组对比剂注射速率均为5.0ml/s,注射对比剂量=1.0ml/kg×体重,注射完后均采用30ml生理盐水冲洗。低剂量组管电压100KVP,管电流200mA,使用威视派克(270mgI/ml)对比剂,使用迭代重建(iDose4)算法,对照组管电压120 KVP,管电流200mA,使用碘佛醇(320mgI/ml)对比剂和滤波反射投影算法(FBP)重建;对各组图像质量进行评分并记录每例患者接受的辐射剂量及碘摄入量,对测量结果进行统计学分析。结果双组图像质量都可以满足诊断要求,图像质量评分差异无统计学意义(P>0.05),颈部血管CT值、信噪比(SNR)、对比噪声比(CNR)、双低组剂量长度乘积(DLP)、碘摄入量差异有统计学意义(P<0.05)。结论应用100KV、低浓度对比剂及迭代重建(iDose4)算法进行头颈部CTA扫描,在不影响图像质量前提下可以大幅度减少患者辐射剂量和对比剂碘摄入量。  相似文献   

3.
复合苯氧羧酸类物质(CBS)作为新的生化制剂,对杂交水稻制种试验。结果表明:每667m2喷8g赤霉素配合CBS制剂50ml较单喷赤霉素15g(正常用量)增产18.7kg,增12.8%,且节约赤霉素7g;较喷8g赤霉素配合浙农大Ⅱ号100ml增产59.45kg,增60.9%;喷8g赤霉素配合浙农大臣Ⅱ100ml十洞科1号250ml十磷酸二氢钾2509增产20.7kg,增15.2%。如进一步与自己研制的助效剂4号配合还可再增10kg/667m2。  相似文献   

4.
对选用不同的萃取剂、在不同的萃取剂用量、萃取次数以及萃取剂的回收再利用等方面进行探讨.结果选用环己酮作萃取剂,按污水与萃取剂之比分别为10:1,15:1,20:1,30:1分三次萃取,水相中CODQ去除率分别达到91.6%,89.3%,88.2%,82%.表明采用环己酮作为萃取剂来处理皂化废碱液是有效的.  相似文献   

5.
MN—202对炼油厂循环水杀菌性能的研究比较   总被引:1,自引:0,他引:1  
对茂石化炼油厂循环水用杀生剂MN-202的杀菌性能进行了实验室静态模拟,并与新洁而灭进行了研究比较,表明前者是一种广谱,高效,低毒的杀生剂,对水中不同的菌种,异养菌,硫细菌,硫酸盐还原菌,MN-202的杀菌效果略好于新洁而灭,且随浓度,作用时间不同又有其特点,在投配浓度为20mg/L时,杀菌效果良好。  相似文献   

6.
乙醇提取八角茴香油工艺的研究   总被引:18,自引:0,他引:18  
研究了用95%乙醇提取八角茴香油的最佳工艺条件,比较了索氏(热回流)提取法与冷浸取法的效果。索氏提取法最佳工艺条件是:料剂比(g/ml)为15:100回流4h;冷浸取法料剂比(g/ml)为5:100,室温浸泡4d,两均不必调pH值。用重量法测蜡和胶体的含量,用傅立叶变换红外光谱仪鉴定其成分。发现索氏提取法周期短,效率较高,产品杂质较少,由此可见,索氏提取法优于冷浸取法。  相似文献   

7.
高分子聚合物可以有效降低钻井液的滤失量,改善钻井液的流变性能。采用水溶液聚合,以丙烯酸、丙烯酰胺为单体,过硫酸铵为引发剂制备了共聚物型降滤失剂,通过正交实验确定了最佳反应条件:即丙烯酰胺和丙烯酸的质量比为3:2,单体加量10%,引发剂加量0.2ml,反应温度为75℃,反应时间为3h。同时对其降滤失性能进行了讨论。  相似文献   

8.
在分析测定中广泛应用隐蔽剂和解蔽剂,以消除干扰离子的影响,本文就它们在终合滴定法,光度分析法,沉淀分析法中的应用,进行了综合性阐述。  相似文献   

9.
WJ抗高温耐碱凝胶型调剖剂的室内试验研究   总被引:2,自引:0,他引:2  
系统地研究了一种聚丙酰胺为主要成分的抗高温、耐碱凝胶型调剖剂体系,考查了聚丙烯酰胺、稳定剂、温度、pH值、矿化度等因素对调剖剂性能的影响。通过L25(5^6)正交表优化了配方并进行了性能评价。实验结果表明,配方体系在30~130℃条件下都能成胶,成胶时间在3~30d可控,pH值范围为7~14,成胶粘度3.0~40Pa·s,岩心的封堵率〉95%,突破压力梯度〉4MPa/m,残余阻力系数〉100,适用于高温强碱油藏的调剖作业。  相似文献   

10.
烟花爆竹中的“烟火药”成分非常复杂,但是一般主要由氧化剂、可燃剂、发色剂和其他特效药剂四部分组成。氧化剂和可燃剂是药剂的主体,发生氧化还原反应。发色剂和发光剂、发烟剂、粘合剂、钝化剂、稳定剂、加速或减速剂、发声剂、防腐剂、防潮剂等特效药剂也不可或缺,他们能增加烟花爆竹的观赏性、艺术性、趣味性、感染性、稳定性和安全性。药剂的燃烧包含着一系列复杂的化学反应,而且绝大多数都是固相反应,蕴含着许多有趣的化学知识。  相似文献   

11.
汉字倒说     
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。  相似文献   

12.
钱生钱!     
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了  相似文献   

13.
The problem on the geometrc inequalities involving an n-dimensional simplex and its inscribed simplex is studied. Aninequality is established, which reveals that the difference between the squared circumradius of the n-dimensional simplex andthe squared distance between its circumcenter and barycenter times the squared circumradius of its inscribed simplex is not lessthan the 2(n-1)th power of n times its squared inradius, and is equal to when the simplex is regular and its inscribed siplex is atangent point one. Deduction from this inequality reaches a generalization of n-dimensional Euler inequality indicating that thecircumradius of the simplex is not less than the n-fold inradius. Another inequality is derived to present the relationship betweenthe circumradius of the n-dimensional simplex and the circumradius and inradius of its pedal simplex.  相似文献   

14.
现在,我们可以没有面包,没有钱,没有房子,没有车子……但我们唯独不能丢失的是高尚的情操,笃定的信念,还有,满满的希望!  相似文献   

15.
Using virtual reality for interactive design gives a designer an intuitive vision of a design and allows the designer to achieve a viable, optimal solution in a timely manner. The article discusses the process of making the Virtual Reality System of the Humble Administrator's Garden. Translating building data to the Virtual Reality Modeling Language (VRML) is by far unsatisfactory. This creates a challenge for computer designers to do optimization to meet requirements. Five different approaches to optimize models have been presented in this paper. The other methods are to optimize VRML and to reduce the file size. This is done by keeping polygon counts to a minimum and by applying such techniques as object culling and level-ofdetail switching.  相似文献   

16.
钱微 《华章》2007,(3):124-124
The awareness of individualism can be traced back to the period of American Revolution when the Declaration of Independence was produced.It expressed basic beliefs concerning freedom,equality,democracy,privacy and the relationship between people and government,which were exactly what the philosophy of individualism mostly dealt with at that time.This paper is to exploit the essence of individualism by analyzing the Declaration .The analysis enables us to reconsider its significance to the issue of America human rights and foreign policies.  相似文献   

17.
Public speaking, as one kind of speech act, the speaker uses some pragmatic strategies, for example,the use of personal pronoun, in order to achieve effective communication. Speakers use the first personal pro-noun we and the second personal pronoun you conventionally, also there are some deviations in the use of person-al pronouns. However, theses kinds of uses have to be explained and understood in such a specific context.  相似文献   

18.
This essay mainly studies the linguistic features of News English on stylistics.The study is made mainly on three aspects of News English.They are lexical features.sentence features and grammar features of News English.Through the study we find that News English,as a distinctive and new language.has its own lin-guistic features in words, sentences and grammar.  相似文献   

19.
《东南大学学报》2014,(3):F0003-F0003
正Journal of Southeast University(English Edition)[JSEU(EE)],a comprehensive academic journal sponsored by Southeast University,was established in1984 and is published quarterly.It is included in Ei Compendex,CA.CSA and MR in America.Scopus in  相似文献   

20.
《东南大学学报》2014,(2):F0003-F0003
正Journal of Southeast University(English Edition)[JSEU(EE)],a comprehensive academic journal sponsored by Southeast University,was established in1984 and is published quarterly.It is included in Ei Compendex,CA,CSA and MR in America,Scopus in the Netherlands,INSPEC in UK?ZB1 MATH in Germany?AJ in Russia,and other databases.This journal publishes up-to-date theoretical and experimental papers of high creativity and great  相似文献   

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