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1.
电镜扫描分析,交变磁场下聚合硫酸铁晶体颗粒尺寸明显比非磁化PFS要大,应该是由于磁结晶效应。采用红外光谱、X射线衍射,确定了磁化作用并没有使PFS形成新羟基键化合物,排除其结构上的差异。而通过紫外光谱分析发现,磁化作用使Fe(c)含量减小,推断在交变磁场作用下,使得Fe3+水合离子化合物的束缚力增强,抑制Fe3+进一步生成Fe(c)这类高聚态化合物,从而使Fe(a)、Fe(b)这类低聚态铁离子水合化合物含量增多。  相似文献   

2.
王福冰 《磁记录材料》1999,17(4):31-33,57
MAMMOS(Magnetic Amplifying Magneto-Optical System)是磁光盘高密度读出的有效方法。由于记录层的磁畴在读出层得以扩大,所以在短磁畴的读出中也能得到与长磁畴读出同等大小的信号。确认在0.04μm磁畴的读出也能获得足够大的信号。在0.2μm的连续记录畴(标记)读出中,其CNR在50dB以上,BER为10^-4左右。应用交变磁场的MAMMOS(MFM-MAMMOS)方法实现了高分辨率及大振幅信号的读出。  相似文献   

3.
为优化磁化除垢条件,进而提高磁化除垢效果,采用正交试验方法对饱和碳酸钙溶液进行磁化试验,并对磁化除垢效果进行表征。结果表明:初始钙离子浓度和电流频率为影响磁化效果的显著因素,磁化时间、线圈匝数和波形为不显著因素。磁化除垢的最优条件:初始钙离子为1 000 mg/L,频率为0.9 kHz,磁化时间为0.5 h,线圈匝数为150圈,波形为方波。  相似文献   

4.
引入外加交变磁场以期提高电镀金刚石工具的性能。SEM观察结果表明:与无磁场影响的镀层相比,外加电压为200V时,胎体晶粒尺寸得到细化,镀层的显微硬度提高1 060MPa。磨削实验表明:外加电压为200V时,所制得的金刚石工具与传统无磁场影响下所制得的金刚石工具相比,使用寿命为其1.5倍,工作效率提高了20.21%。  相似文献   

5.
王亮  延克军 《硅酸盐通报》2016,35(7):2298-2303
以聚合硫酸铁(PFS)为研究对象,采用红外(FTIR)、X射线衍射(XRD),确定了磁化对PFS结构的影响;以碱化度(B=OH/Fe)和静置时间为变量,进行pH、紫外(UV)以及Fe-Ferron逐时络合比色法测定,分析了磁化对PFS水解的影响.通过实验证明:磁化作用并没有使PFS形成新羟基健化合物;随着B的升高,磁化使PFS溶液的pH升高,UV下300 nm附近的吸收峰下降减缓;随着静置时间的增加,磁化使Fe(c)含量增长速率减慢.磁化对PFS水解的影响可能是在交变磁场的作用下,Fe3+离子与水分子发生水缔结作用,形成新的水合物,多了一层水合层,阻碍了Fe(a),Fe(b)向Fe(c)转化.  相似文献   

6.
为阐明交变外磁场对硫酸钙垢溶解行为的影响规律,采用离子浓度、电导率和红外光谱等手段检测硫酸钙垢溶解液的性质,并利用X射线衍射(XRD)和检测硫酸钙垢溶解量等方法对硫酸钙垢进行表征和分析。结果表明,交变外磁场对硫酸钙垢的溶解有明显的促进作用。与无磁场作用的硫酸钙垢溶解液相比,交变外磁场作用60 min后硫酸钙垢溶解液的硫酸根质量浓度由2.41 g/L增大至3.52 g/L,电导率由5.85 mS/cm增大至7.24 mS/cm,硫酸钙垢的溶解量增加了40%。外加交变磁场可以促进硫酸钙垢溶解的原因是,外加交变磁场可以使蒸馏水中亲水性羟基的比例增加,促进水分子与硫酸钙垢的分子亲合力。此外,交变外磁场的作用还导致硫酸钙垢的结晶度减小、主晶面的面间距增大,最终有利于垢与水的接触和溶解。此研究可为利用交变外磁场调控硫酸钙垢的溶解行为提供理论依据。  相似文献   

7.
直流磁场作用下水的过冷和结晶现象   总被引:2,自引:2,他引:0       下载免费PDF全文
周子鹏  赵红霞  韩吉田 《化工学报》2012,63(5):1405-1408
引言水及水溶液的过冷度变化和冻结过程在生物低温保存、过冷法制冰浆和食品冷冻冷藏保鲜中有着重要的作用[1-3]。近年来,已有一些研究者采用磁场对水及水溶液的影响进行了一些探索,但是还有  相似文献   

8.
将交变磁场引入自蔓延高温合成反应,研究其对Al2O3复合管陶瓷层结构和力学性能的影响.结果表明:交变磁场可以促进燃烧反应的进行,随着磁感应强度的增加,α-Al2O3的枝晶尺寸减小,形态逐渐向细小的等轴晶形态过渡.复合管的抗压强度和抗剪强度随着磁感应强度的增加而增加.其中当磁感应强度为0.20T时,抗压强度和抗剪强度分别达418MPa和19.5MPa,比未引入交变磁场前分别提高了19.1%和21.9%.  相似文献   

9.
研究了羰基铁粉热处理前后的微观结构、磁性能以及二者在定向集热治疗肿瘤医用交变磁场下的发热性能,羰基铁粉经过热处理后在外部交变磁场作用下的发热性能明显提高.随着经过热处理的羰基铁粉用量的增大,能够达到的最高温度也随之增大,短时间内就能达到有效杀伤肿瘤细胞的温度,经过热处理后的羰基铁粉是定向集热治疗肿瘤的一种理想候选热籽材料,羰基铁粉在外部交变磁场作用下的发热主要来自磁滞损耗和奈尔松弛.  相似文献   

10.
半导体光催化氧化技术在处理有机废水中具有突出优点,本文在优化条件下,利用自制的新型光催化反应器对苯酚模拟废水进行降解,探究交变磁场对不同波长的光源催化降解苯酚的影响以及随时间的变化,通过实验证明交变磁场可以与光源产生耦合作用,对光催化降解苯酚起促进作用。  相似文献   

11.
咸潮对氯消毒中三卤甲烷的影响   总被引:2,自引:0,他引:2  
陈飒  占永革 《净水技术》2007,26(1):76-79
受咸潮影响的出厂水三卤甲烷比非咸潮时高5倍,其中三溴甲烷增加10~4倍,远远大于三氯甲烷,4种THM8含量顺序发生了倒置,即CHBr_3>CHBr_2Cl>CHBrCl_2>CHCl_3。在管网中咸潮污染的出厂水和未污染水混合,加之余氯的作用,使得管网水中三卤甲烷(THMs)的种类分配再次发生变化。结合国内外的资料,综合评述了咸潮中溴化物与氯的反应及Br-THMs形成的机理,并提出了在咸潮期间控制饮用水中氯化消毒产物的思路。  相似文献   

12.
The major problem of current drug-based therapy is selectivity. As in other areas of science, a combined approach might improve the situation decisively. The idea is to use the pro-drug principle together with an alternating magnetic field as physical stimulus, which can be applied in a spatially and temporarily controlled manner. As a proof of principle, the neutral hydrolysis of aspirin in physiological phosphate buffer of pH 7.5 at 40 °C was chosen. The sensor and actuator system is a commercially available gold nanoparticle (NP) suspension which is approved for animal usage, stable in high concentrations and reproducibly available. Applying the alternating magnetic field of a conventional NMR magnet system accelerated the hydrolysis of aspirin in solution.  相似文献   

13.
水流以一定的速度经过磁场装置处理后得到的水称为磁化水.本实验设计了不同的磁场强度(280 mT,450 mT,650 mT,800 mT)、水流速度(0.4 m/s,0.6 m/s,0.7 m/s,0.9 m/s,1.0 m/s)和水流循环次数等参数来研究磁活化水对水泥拌合物的性能影响.结果表明:磁化水的pH值都高于普通水,不同循环次数的磁化水在紫外区的吸光度也明显增大;当磁场强度为280 mT,水流速度为0.9~1.0 m/s时,磁化水拌和水泥浆有较好的流变性其流动度也增大;磁化水拌制的砂浆试块28 d后的抗压强度有很大提高.  相似文献   

14.
马健伟  宋亚瑞 《广东化工》2012,39(13):83-83
概述了磁分离技术的原理、设备及在水处理中的应用,并展望了该技术在水处理中的应用前景。  相似文献   

15.
Although osteosarcoma is the most common primary malignant bone tumor, chemotherapeutic drugs and treatment have failed to increase the five-year survival rate over the last three decades. We previously demonstrated that type 5 metabotropic glutamate receptor, mGluR5, is required to proliferate metastatic osteosarcoma cells. In this work, we delivered mGluR5 siRNAs in vitro using superparamagnetic iron oxide nanocages (IO-nanocages) as delivery vehicles and applied alternating magnetic fields (AMFs) to improve mGluR5 siRNAs release. We observed functional outcomes when mGluR5 expression is silenced in human and mouse osteosarcoma cell lines. The results elucidated that the mGluR5 siRNAs were successfully delivered by IO-nanocages and their release was enhanced by AMFs, leading to mGluR5 silencing. Moreover, we observed that the proliferation of both human and mouse osteosarcoma cells decreased significantly when mGluR5 expression was silenced in the cells. This novel magnetic siRNA delivery methodology was capable of silencing mGluR5 expression significantly in osteosarcoma cell lines under the AMFs, and our data suggested that this method can be further used in future clinical applications in cancer therapy.  相似文献   

16.
The reversal of loss of the critical size of skeletal muscle is urgently required using biomaterial scaffolds to guide tissue regeneration. In this work, coaxial electrospun magnetic nanofibrous scaffolds were fabricated, with gelatin (Gel) as the shell of the fiber and polyurethane (PU) as the core. Iron oxide nanoparticles (Mag) of 10 nm diameter were added to the shell and core layer. Myoblast cells (C2C12) were cultured on the magnetic scaffolds and exposed to the applied magnetic fields. A mouse model of skeletal muscle injury was used to evaluate the repair guided by the scaffolds under the magnetic fields. It was shown that VEGF secretion and MyoG expression for the myoblast cells grown on the magnetic scaffolds under the magnetic fields were significantly increased, while, the gene expression of Myh4 was up-regulated. Results from an in vivo study indicated that the process of skeletal muscle regeneration in the mouse muscle injury model was accelerated by using the magnetic actuated strategy, which was verified by histochemical analysis, immunofluorescence staining of CD31, electrophysiological measurement and ultrasound imaging. In conclusion, the integration of a magnetic scaffold combined with the extra magnetic fields enhanced myoblast differentiation and VEGF secretion and accelerated the defect repair of skeletal muscle in situ.  相似文献   

17.
ADC发泡剂高含盐废水污染防治   总被引:4,自引:0,他引:4  
周琦  张万青  苏鸿钧  李美菊 《广东化工》2007,34(2):54-56,45
ADC发泡剂是一个很好的氯气下游产品,经济效益可观,但它所带来的环境影响不容忽视。本文试从ADC发泡剂的生产工艺流程出发,找出污染环节并提出污染防治对策。  相似文献   

18.
饮用水与矿化水溶液的磁光协同处理技术研究   总被引:2,自引:0,他引:2  
施其宏  于洋  高菲 《水处理技术》2001,27(6):326-328
本文对同时采用磁场和紫外光协同处理水和无机盐(矿物质)对溶液进行了研究。结果表明协同处理可显著提高水对紫外光的吸光度。作者通过谨慎设计的一系列实验,研究了外加磁场强度与紫外吸光度的关系、磁化水的记忆效应,并讨论了磁光协同处理的作用机理,探讨了开发磁光协同进行灭菌处理的可能性。  相似文献   

19.
Results of an experimental investigation of electric and magnetic fields generated by explosions of charges of a chemical high explosive in the frequency range of 0–10 kHz are presented. It is shown that the characteristics of signals of the electric and magnetic fields registered in explosions of highexplosive charges in air, on the ground surface, and in underground explosions are significantly different.  相似文献   

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