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1.
应用TEM、XPS、XRD等分析技术,研究了包钴过程中各种因素对钴改性γ-Fe_2O_3磁粉的微观结构以及磁性能的影响。结果表明,钴铁氧体的形成是Co-γ-Fe_2O_3磁粉磁性能提高的主要原因。包少量钴(钴含量<1%),可使原磁粉的矫顽力提高约6.37kA/m。  相似文献   

2.
研究了热处理过程中α-Fe_2O_3还原、Fe_3O_4氧化机理,考察了还原、氧化条件对γ-Fe_2O_3微观结构及磁性的影响。结果表明,还原温度和还原气空速是影响还原程度的重要参数。当还原温度为380℃、空速为1200h~(-1)时,所获磁粉矫顽力最高。Fe_3O_4烧结为表面扩散控制。Fe_3O_4向γ-Fe_2O_3的相变过程能加速粒子烧结。同时发现,当Fe_3O_4氧化不充分时,立方γ-Fe_2O_3中存在四方γ-Fe_2O_3杂相。  相似文献   

3.
利用广延X射线精细结构和X射线吸收近边结构技术,结合高分辨电镜和磁性能测量,研究了各种还原温度处理后的包钴型γ-Fe_2O_3磁粉的微结构与磁性能的关系。结果表明,还原温度对包钴型γ-Fe_2O_3磁粉的表面层结构的形成、转变影响很大,350℃左右的热处理能够形成较理想的表面层结构,增大磁各向异性,从而大幅度提高其矫顽力。  相似文献   

4.
采用DTA、TEM、HREM、SEAD、BET等实验手段,研究了α-FeOOH脱水相变过程中空洞形成机理,并考察了焙烧温度、气氛对γ-Fe_2O_3磁性能的影响。结果表明,γ-Fe_2O_3空洞主要由脱水过程中α-FeOOH内部OH~-脱除时产生,铁黄表面缺陷部位和α-FeOOH初级粒子凝并区域是脱水相变的“发源地”。当在450℃湿空气下焙烧时,最终获得的磁粉性能较佳。  相似文献   

5.
本文运用差热分析、X-衍射分析、偏光显微镜和电子显微镜的分析,研究了某些氧化物(SnO_2、Ta_2O_5和PbO)对ZnO-B_2O_3-SiO_2系钝化玻璃在热处理前后性能的影响。认为该系统结晶型钝化玻璃析出的晶相主要是ZnSiO_4、α-Zn_5B_4O_(11)及Zn_3B_2O_6,而且通过热处理可控制和调节玻璃的物化性能。该类玻璃可用作硅元件的钝化材料。  相似文献   

6.
研究了包敷磷酸盐和稀土氧化物对α-FeOOH分散性、γ-Fe_2O_3热稳定性和磁性能的影响规律。结果发现,包敷磷酸盐能明显提高γ-Fe_2O_3磁性能。此类包敷剂的作用效应为六偏磷酸钠>高聚磷酸钠>焦磷酸钠。La_2O_3可阻止γ-Fe_2O_3烧结和相变,该作册源于La~(3+)在γ-Fe_2O_3晶格母体的填隙和La_2O_3与γ-Fe_2O_3间的界面化学作用。  相似文献   

7.
目的 利用磁性/荧光量子点双功能纳米粒子双标记大鼠骨髓间充质干细胞(BMSC),探讨标记效率和可行性.方法 分离、纯化及培养大鼠BMSC.制备二氧化硅(SiO_2)同时包裹四氧化三铁(Fe_3O_4)和碲化镉(CdTe)荧光量子点的磁性/荧光双功能纳米粒子Fe_3O_4@CdTe@SiO_2:,利用铁浓度为25μg/ml的Fe_3O_4@CdTe@SiO_2标记BMSC,未标记的BMSC作为对照组.通过荧光显微镜观察细胞内纳米粒子的荧光表达情况.双标记后的BMSC分成8个不同数量级(3×10~6~1×10~3个),应用1.5 T磁共振扫描仪进行T_1 WI、T_2 WI和T_2~* WI 3个序列成像.分光光度计测量细胞铁含量,普鲁士蓝染色显示细胞内铁.结果 荧光显微镜下可见双标记组细胞内Fe_3O_4@CdTe@SiO_2:纳米粒子显示为红色荧光,细胞标记率达到90%以上.磁共振成像可见3×10~6~5×10~4双标记组细胞较对照组T_2 WI、T_2~* WI信号减低,两组之间的信号差异随数量级减小而相应减小,T_2~* WI信号变化最明显,T_2WI次之.细胞铁含量为(14.05±4.15)pg/细胞,普鲁士蓝染色可见双标记细胞胞质内蓝染的含铁颗粒.结论 Fe_3O_4@CdTe@SiO_2,纳米粒子可同时对大鼠BMSC进行磁性和荧光双标记,有望成为磁共振和光学成像活体示踪移植后BMSC的有效手段.  相似文献   

8.
以V_2O_5,C_2H_5OH和SOCl_2为原料,用氨法合成了釩的醇盐Vo(OC_2H_5)_3。将玻璃在其乙醇溶液中浸涂、热处理后,得到表面无定形V_2O_5导电膜。浸涂液中乙醇和钒醇盐体积比为14,水和钒醇盐摩尔比为2或3时,导电膜均匀、透明,并具良好的导电性。随着热处理温度的升高及热处理时间的延长,涂膜的厚度减少,膜与基体玻璃的结合增强,膜的电导率逐渐上升,在320℃时达到最大值,为3.5×10~(-2)Ω~(-1)。cm~(-1)。透射电镜分析表明,VO(OC_2H_5)_3水解后得到的凝胶具有纤维状显微结构。凝胶的傅里叶转换红外吸收光谱显示V_2O_5的特征吸收峰。差热和X射线衍射分析表明,在340℃凝胶中V_3O_5晶化。  相似文献   

9.
动脉栓塞用磁性流体材料制备的研究   总被引:2,自引:0,他引:2  
目的:探讨用于动物实验动脉栓塞的磁性流体材料 Fe_3O_4制备方法。方法:观察比较不同制备条件,如碱比 n、Fe~(2+)/Fe~(3+)比、反应温度、分散剂等对反应产物的影响。结果:在反应温度36℃~40℃,Fe~(2+):Fe~(3+):OH~-=1:2:n(n>10),及分散剂存在下制出了粒径0.2~0.8μm、强磁性的 Fe_3O_4材料。结论:控制反应条件是制备合乎要求 Fe_3O_4材料的关键因素。  相似文献   

10.
目的 研究四氧化三铁(磁性Fe3O4)纳米颗粒对人角质形成细胞(HaCaT)超微结构的影响。方法 将不同浓度的Fe3O4磁性纳米颗粒悬液加入培养的HaCaT细胞中,在37℃、5%CO2的细胞培养箱中共同孵育4 h,收集细胞进行常规透射电镜制样,在透射电镜下观察纳米Fe3O4颗粒进入细胞的方式及细胞超微结构的改变。结果 Fe3O4磁性纳米颗粒平均粒径为12 nm。在不同浓度下Fe3O4磁性纳米颗粒均能以吞噬的方式进入细胞,进入细胞后再从吞噬泡中释出,主要对其附近的线粒体造成影响,线粒体出现肿胀,线粒体嵴溶解。 结论 Fe3O4磁性纳米颗粒主要对HaCaT细胞中颗粒附近的线粒体结构有损伤,且存在浓度依赖性。  相似文献   

11.
FOR anesthesiologis s ,treatingpostoperativepainhas alwaysbeen a problem.Althoughopioidshave been provedtobe effective,theirsideeffectscouldnotbeignored.With thedevelopmentofscienceand pharmacology,many drugs with aspectsof satisfactoryanalgesicefficacyand couldbe welltoleratedby patientshave been developed.And lornoxicamisone of them, which isa non-steroidalanti-inflammatorydrug (NSAID ), with analgesic, anti-infl-ammatory,andantipyreticproperties.Itseliminationhalf-time(3 to 5 hours) isle…  相似文献   

12.
Dr.Zhang Ren,the chief physician,is the chairman of Shanghai Acupuncture and Moxibustion Association.Having been engaged in medicine for about 40 years,he is experienced in treating various intractable diseases.In his long years of clinical practice,he advocates taking the TCM differentiation as the basis to seek for the acupuncture method for treatment of modern intractable diseases.The author of this essay had the fortune to follow Dr.Zhang in study.The following is a summary of Dr.Zhang's experience in the acupuncture treatment for different intractable diseases with the same therapeutic principle.  相似文献   

13.
In treating chronic nephropathy,Luo Lingjie,a chief physician,pays attention to regulating the balance between yin and yang,treating infection if present,and removing pathogenic factors.He prescribes gentle drugs and uses carefully strongly warming-tonifying ones,emphasizes the importance of persuading the patient to persist in treatment with medication and nurse one's health for recuperation,and is good at combined use of TCM and western medicine therapy and brings the merits of various therapies into full play,with obvious theraoeutic effects.  相似文献   

14.
Objective: To observe the therapeutic effects in acupunture treatment of primary dysmenorrhea combined with spinal Tui Na, and study its mechanism. Methods: Thirty cases of the treatment group were treated by acupuncture combined with spinal Tui Na, and thirty cases in the control group were treated by routine acupuncture. Results: The total effective rate was 93.3% in the treatment group, and 73.3% in the control group, with a significant difference between the two groups (P<0.05). Conclusions: Acupuncture combined with spinal Tui Na has good prospects for treatment of primary dysmenorrhea.  相似文献   

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16.
目的 探讨猪肺磷脂注射液联合经鼻持续气道正压通气(NCPAP)对呼吸衰竭早产儿的临床疗效及肌酸激酶同工酶活性(CK-MB)的影响.方法 选取呼吸衰竭早产儿80例,分为观察组和对照组各40例.对照组采用NCPAP给氧治疗,观察组给予NCPAP给氧联合猪肺磷脂气管内给药.观察两组患儿治疗前及治疗12h、24 h后PaO2、PaCO2、血氧饱和度(SaO2)、pH的变化情况,检测治疗前及治疗5d后血清CK-MB水平;评估两组患儿的临床治疗效果.结果 两组患儿PaO2、PaCO2、SaO2、pH比较,差异均有统计学意义(P<0.05),其中观察组治疗后的PaO2、SaO2、pH均高于对照组,PaCO2则低于对照组.两组的PaO2、SaO2、pH均随观察时间延长而升高(P<0.05),PaCO2均随观察时间的延长而降低(P<0.05).观察组治疗有效率为87.5%,显著高于对照组的70.0% (P <0.05).治疗5d后两组患儿血清CK-MB水平均较前降低(P<0.05),且观察组明显低于对照组(P<0.05).结论 猪肺磷脂注射液气管内给药联合NCPAP可以显著降低呼吸衰竭早产儿CK-MB的含量,提高治疗有效率,起到很好的呼吸循环支持作用.  相似文献   

17.
Evidence obtained from randomized controlled trials (RCTs) has been generally accepted as the gold standard in the evaluation of clinical effectiveness. Readers need to understand the trial design, implementation, results, analysis and interpretation, so as to fully Jnderstand the results of RCTs. Thus, the investigators of RCTs have to report these items in a complete, accurate and clear manner. Since 1998, we have conducted several evaluations on the reporting quality of RCTs published in Chinese journals on traditional Chinese medicine (TCM) and results have shown that there is an urgent need for higher quality RCTs on TCM.  相似文献   

18.
Ankylosing spondylitis is a chronic and progressive disorder with inflammation mainly involving the central axis joints. It mainly affects the cervical spine and the lumbosacral area, with the pathogenesis closely related to the kidney and the Governor Vessel (GV). TCM holds that the syndrome is deficiency in origin and excess in superficiality, which is due to insufficiency of the kidney, deficiency of GV, and blocking of the channels with the invasion of exogenous evil, leading to poor circulation of qi and blood and malnutrition of the bones, muscles and joints. The TCM method of tonifying the kidney and strengthening GV to regulate circulation of qi and blood and check the arthralgia pain should be adopted, with the Kidney-Tonifying and GV Strengthening Decoction (益肾强督汤) prescribed.  相似文献   

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CHEMOTHERAPY playsa greatrolein the treat- ment of malignanttumors,especiallyingynecolo- gicalones.But inanticancerchemotherapy,leuko-cytopeniaisfrequentlytheprimarydose-limitingsideeffect factor.Moreover,cancersarefrequentlychemoresistantbe-causeof overexpressionof P-glycoprotein(P-gp), which isencodedby multidrugresistancegene (MDR1 ) and detectableinup to50% ofhuman cancersand renderscellsresistancetoanticancerdrugs.The safetyand potentialtherapeuticbenefitof mdr1 gene transferredto h…  相似文献   

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