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Maintained Exposure to Spring Water but Not Double Distilled Water in Darkness and Thixotropic Conditions to Weak (~1 µT) Temporally Patterned Magnetic Fields Shift Photon Spectroscopic Wavelengths: Effects of Different Shielding Materials 被引量:2
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作者 N. J. Murugan L. M. Karbowski +1 位作者 R. M. Lafrenie M. A. Persinger 《Journal of Biophysical Chemistry》 2015年第1期14-28,共15页
Spring water but not double-distilled water was exposed, in darkness, to a temporally patterned weak magnetic field that has been shown to affect planarian behavior and slow the rate of cancer cell proliferation. Expo... Spring water but not double-distilled water was exposed, in darkness, to a temporally patterned weak magnetic field that has been shown to affect planarian behavior and slow the rate of cancer cell proliferation. Exposure to the magnetic field caused a reliable shift in the peak (longer) wave-length of ~10 nm for fluorescence emissions and a ~20% increase (~100 counts) in fluorescence intensity. Spectral analyses verified a shift of 5 and 10 nm, equivalent to ~1.5 × 10-20 J “periodicity” across the measured wavelengths, which could reflect a change in the an intrinsic energy as predicted by Del Giudice and Preparata and could correspond to two lengths of O-H bonds. Wrapping the water sample containers during exposure with copper foil, aluminum foil, or plastic altered these fluorescent profiles. The most conspicuous effect was the elimination of a ~280 nm peak in the UV-VIS emission spectra only for samples wrapped with copper foil but not aluminum or plastic. These results suggest that weak magnetic fields produce alterations in the water-ionic complexes sufficient to be reliably measured by spectrophotometry. Because the effect was most pronounced when the spring water was exposed in darkness and was not disturbed the role of thixotropic phenomena and Del Giudice entrapment of magnetic fields within coherent domains of Pollack virtual exclusion zones (EZ) may have set the conditions for subsequent release of the energy as photons. 展开更多
关键词 Water weak magnetic fields PHOTON Emissions DARKNESS Thixotropic Phenomena Copper Shielding Wavelength SHIFT 10-20 Joules
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EXTREMELY LOW FREQUENCY MAGNETIC FIELD SUSCEPTIBILITY OF VISUAL DISPLAY UNITS
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作者 傅正财 杜亚平 J.Burnett 《Journal of Shanghai Jiaotong university(Science)》 EI 2001年第2期201-205,共5页
Extremely low frequency (ELF) magnetic field susceptibility is an index of visual display unit (VDU) quality and performance. This paper provided field measured data on the susceptibility for a large variety of VDUs. ... Extremely low frequency (ELF) magnetic field susceptibility is an index of visual display unit (VDU) quality and performance. This paper provided field measured data on the susceptibility for a large variety of VDUs. A test rig was built to study the susceptibility of VDUs to magnetic fields at fundamental and third harmonic frequencies. It was found that the susceptibility level is largely dependent on refresh rate of the VDU and the orientation of the external ELF field. It was also found that the VDU susceptibility is significantly increased in the presence of harmonic frequency magnetic fields. About 30% of the tested samples have susceptibility levels higher than that stated in IEC 1000-4-8 standard. 展开更多
关键词 visual display unit extremely low frequency magnetic field electromagnetic compatibility susceptibility test
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Progressive Obesity in Female Rats from Synergistic Interactions between Drugs and Whole Body Application of Weak, Physiologically Patterned Magnetic Fields
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作者 Linda S. St-Pierre Michael A. Persinger 《Journal of Behavioral and Brain Science》 2014年第6期268-283,共16页
Prepubescent female rats treated with the atypical neuroleptic acepromazine but not ketamine, prazosin, or doxepin, after lithium/pilocarpine-induced seizures gradually became obese over their lifetimes if spontaneous... Prepubescent female rats treated with the atypical neuroleptic acepromazine but not ketamine, prazosin, or doxepin, after lithium/pilocarpine-induced seizures gradually became obese over their lifetimes if spontaneous seizures developed. Mild increases in weight gain were induced when prepuberal females were given pilocarpine and acepromazine while being exposed briefly (1.5 hr) to a frequency-modulated magnetic field known to induce seizures. Weekly (1.5 hr) exposures to physiologically-patterned magnetic fields over 36 wks had no effect on weight gain while continuous periseizure exposure to 50 Hz fields above about 1 μT facilitated mild weight gains and protracted aggression. Perinatal exposure to a very weak, a 7 Hz magnetic field or a nitric oxide inhibitor retarded the weight gain induced by the obesity procedure. These results indicate that synergisms during a single episode between neuronal electrical lability and pharmacological states can initiate a process of weight gain that progresses to extreme obesity. We suggest that at least a component of the global “epidemic of obesity” could be related to a synergism between the insidious emergence of amplitude modulations within biologically compatible electromagnetic frequencies from the proliferation of communication systems and the pervasive utilization of pharmacology to treat transient disorders of ontogeny within the human population. 展开更多
关键词 OBESITY Drug-Induce OBESITY weak magnetic fields Drug-magnetic field Synergisms
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Combined Effects of 50 Hz Magnetic Field and Magnetic Nanoparticles on the Proliferation and Apoptosis of PC12 Cells 被引量:2
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作者 JIA Hong Li WANG Chao +4 位作者 LI Yue LU Yan WANG Ping Ping PAN Wei Dong SONG Tao 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第2期97-105,共9页
Objective To investigate the bioeffects of extremely low frequency (ELF) magnetic field (MF) (50 Hz, 400 μT) and magnetic nanoparticles (MNPs) via cytotoxicity and apoptosis assays on PC12 cells. Methods MNPs... Objective To investigate the bioeffects of extremely low frequency (ELF) magnetic field (MF) (50 Hz, 400 μT) and magnetic nanoparticles (MNPs) via cytotoxicity and apoptosis assays on PC12 cells. Methods MNPs modified by SiO2 (MNP-SiO2) were characterized by transmission electron microscopy (TEM), dynamic light scattering and hysteresis loop measurement. PC12 cells were administrated with MNP-SiO2 with or without MF exposure for 48 h. Cytotoxicity and apoptosis were evaluated with MTI- assay and annexin V-FITC/PI staining, respectively. The morphology and uptake of MNP-SiO2 were determined by TEM. MF simulation was performed by Ansoft Maxwell based on the finite element method. Results MNP-SiO2 were identified as -20 nm (diameter) ferromagnetic particles. MNP-SiO2 reduced cell viability in a dose-dependent manner. MF also reduced cell viability with increasing concentrations of MNP-SiO2. MNP-SiO2 alone did not cause apoptosis in PC12 cells; instead, the proportion of apoptotic cells increased significantly under MF exposure and increasing doses of MNP-SiO2. MNP-SiO2 could be ingested and then cause a slight change in cell morphology. Conclusion Combined exposure of MF and MNP-SiO2 resulted in remarkable cytotoxicity and increased apoptosis in PC12 cells. The results suggested that MF exposure could strengthen the MF of MNPs, which may enhance the bioeffects of ELF MF. 展开更多
关键词 extremely low frequency magnetic field magnetic nanoparticles CYTOTOXICITY APOPTOSIS MORPHOLOGY
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Association between Childhood Leukaemia and Exposure to Power-frequency Magnetic Fields in Middle Europe 被引量:1
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作者 Vitezslav JIRIK Ludek PEKAREK +1 位作者 Vladimir JANOUT Hana TOMASKOVA 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2012年第5期597-601,共5页
Abstract Objective Higher levels of exposure to extremely low-frequency magnetic fields (ELF-MF) are associated with a slightly increased risk of childhood leukaemia. Compared with more-developed Western countries, ... Abstract Objective Higher levels of exposure to extremely low-frequency magnetic fields (ELF-MF) are associated with a slightly increased risk of childhood leukaemia. Compared with more-developed Western countries, higher exposure levels are evident in the Czech Republic, probably because of the different types of housing. In light of this, we aimed to examine the association between ELF-MF exposure and childhood leukaemia in the Czech Republic. Methods We conducted a paired case-control study. The cases (children with leukaemia) were age- sex- and permanent residence-matched to controls (children without leukaemia). Although this limited potential bias and confounding, it also limited our number of participants. Results The matched analyses included 79 case-control pairs. No significant association between ELF-MF exposure and childhood leukaemia was observed for exposures over 0.2 μT (odds ratio [0R]=0.93, confidence interval [Cl]=0.45-1.93), 0.3 μT (0R=0.77, Cl=0.34-1.75), or 0.4 μT (OR=0.9, Cl=0.37-2.22). Conclusion Despite higher levels of exposure in Middle and Eastern Europe, no indication of an association between ELF-MF exposure and childhood leukaemia was determined. This in contrast to the findings of previous studies conducted in different countries. 展开更多
关键词 Childhood leukaemia Power-frequency magnetic field exposure extremely low-frequencymagnetic field Housing types
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Temperature Dependent Zeno Time for a Two Level Atom Traversing through a Thermal Magnetic Barrier in the Framework of Weak Measurement
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作者 Samyadeb Bhattacharya Sisir Roy 《Journal of Modern Physics》 2015年第9期1261-1269,共9页
The Zeno time has been calculated for a metastable two-level atom tunneling through a interacting thermal magnetic field. The process of weak measurement has been utilized for the estimation of the timescale. Zeno tim... The Zeno time has been calculated for a metastable two-level atom tunneling through a interacting thermal magnetic field. The process of weak measurement has been utilized for the estimation of the timescale. Zeno time has been shown to be temperature dependent. From the calculation it is evident that the Zeno time decreases with the increase of temperature. Moreover, the result restricts the Zeno time to a maximum limiting value, irrespective of how frequent the measurement process is. 展开更多
关键词 Zeno TIME weak MEASUREMENT DISSIPATIVE System THERMAL magnetic field
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Geological Specimens, Minerals, and Actions Affecting Polar Shift and Earth’s Magnetic Field
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作者 Shreyas Banaji 《International Journal of Geosciences》 CAS 2022年第10期875-881,共7页
This study will touch upon Earth’s magnetic field, the four spheres, and their relationship with polar shift influenced by the magnetization of the interior and surface areas. It will outline how certain aspects with... This study will touch upon Earth’s magnetic field, the four spheres, and their relationship with polar shift influenced by the magnetization of the interior and surface areas. It will outline how certain aspects within the spheres are influenced by magnetization of minerals and localized rock, how such can be contained deep within Earth’s mantle areas, as well as how mining deposits of iron ore can affect other spheres and systems. It will also entail a brief explanation of geological research concerning the Pacific Ocean floor, as well as a discussion on the magnetization of minerals retaining their properties at extremely high temperatures within Earth’s interior. There will be explanations of how various spheres interact with each other, but it should be noted that while some findings here might seem unsubstantiated, any analysis of Earth’s interior and exterior, the magnetic field, polar shift, and its contagion effect upon living organisms, is still, somewhat, in its initial research stages, and is, at times, left to hypotheses concerning anomalous indications. This study is not conclusive. It has, at best, pieced together areas of relevance. Concluded here is that each event affects polar shift. How this has been affected by magnetization is not completely, at this time, understood. Furthermore, this report in no way promotes the “doomsday scenario”, prolific, fairly recently, within some of the scientific literature on this subject, particularly in Europe. This paper closely adheres to the most modern theories, and will try, at best, to leave speculation to science fiction writers. 展开更多
关键词 Polar Shift magnetic field Atmosphere LITHOSPHERE HYDROSPHERE BIOSPHERE Iron Ore hematite Magnetite
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Radical involved reactive wetting and retarding mechanism of alumina refractory ceramic by molten slags under weak static magnetic field
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作者 Sheng-hao Li Ao Huang +5 位作者 Fan-bo Zeng Hui Peng Hao-ran Wei Xue-chun Huang Sheng-qiang Song Hua-zhi Gu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2024年第6期1355-1366,共12页
High alumina slag will cause severe corrosion at the interface of alumina refractory,and the wetting behavior of slag is a key factor influencing the corrosion resistance of refractory ceramics.The static magnetic fie... High alumina slag will cause severe corrosion at the interface of alumina refractory,and the wetting behavior of slag is a key factor influencing the corrosion resistance of refractory ceramics.The static magnetic field is a promising solution for improvement in the slag resistance of refractory.The wetting of alumina refractory ceramics with different basicities of high alumina slags under a weak static magnetic field was analyzed,given that a weak static magnetic field can affect the corrosion behavior of refractory ceramics.Taking slag S_(3) as an example,when there was an external static magnetic field of 1.0 mT at 1600 ℃,the thickness of calcium aluminate reaction layer at the interface decreased by 36.7%,the denting depth of interface decreased by 35.6%,and the apparent wetting angle increased by 20%.The living radicals and their formation path in oxide melts were verified by first-principles calculation combined with electron paramagnetic resonance spectroscopy analysis.The influence of the flux density of a weak static magnetic field on the wetting behavior of slags was also explored.The contact angle of the slags increased owing to the inhibitory effect of magnetic field on the radicalinvolved reaction at the interface of the slag and the alumina refractory ceramic.The relationships between the magnetic flux density,diffusion coefficient,slag microstructure(hyperfine coupling constant),and contact angle were established.This provides a theoretical basis for the field control of radical involved reactive wetting between inorganic oxide slags and solid oxide ceramics. 展开更多
关键词 Alumina refractory ceramic Molten slag weak magnetic field effect Reactive wetting Free radical
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High field superconducting magnet: Science, Technology and Applications 被引量:2
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作者 Wang Qiu-Liang 《物理学进展》 CSCD 北大核心 2013年第1期1-23,共23页
关键词 物理学 进展 征订 启事 征稿
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Nuclear Physics with Magnetic Charges 被引量:1
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作者 Robert A. Sizov 《Journal of Modern Physics》 2018年第2期145-171,共27页
The magnetic spinor particles (magnetic charges) are the real structural components all varieties of the Mass, for example, atoms, nucleons, positrons and neutrinos. Atomic-shaped device of Mass is the natural and the... The magnetic spinor particles (magnetic charges) are the real structural components all varieties of the Mass, for example, atoms, nucleons, positrons and neutrinos. Atomic-shaped device of Mass is the natural and the only possible organization of electric and magnetic charges which can create a gravitational field. At level of a popular language one can define nucleons as “small atoms”, and positron and neutrino as “very small atoms”. The electric and magnetic fundamental particles in neutron and proton shells which by tradition should be called quarks have charges of smaller magnitude than the charges of particles in atomic shells. Positron which participates in the gravitational interaction and, consequently, has an atomic-shaped device is the most likely candidate for the role of the proton nucleus. The most likely candidate particles on the participation in nuclei of proton and neutron as well as in nuclei of the positron and neutrino are presented in the article. So-called abnormal magnetic moment of neutron is formed by the quark magnetic dipoles which are like to unpaired electrons in the so-called magnetic atoms rotate on the outer orbitals of the neutron shell. The participation of the “magnetic electron” (magneton) in the neutrino core assumes the existence of the so-called anomalous magnetic moment and in the neutrino shell. The existence of real magnetic charges in the structures of the Mass draws our attention on such important problem as interaction between charges in the framework of electromagnetic dipoles such as and in which manifest the weak attraction. Weak interaction by its nature is electromagnetic. So-called electromagnetic interaction, manifested in pairs of homogeneous charges of opposite signs, is either electric or magnetic, but not electromagnetic. The explanation of the weak interaction in the marked pairs of charges is based on the author’s concept of the World Physical Triad and “Dark Energy”. Forces responsible for the interaction of the charges composing the electromagnetic dipoles correspond, conditionally of the weak charges of the particles which what assume mutual suppression of the influence of their fields on the Energo-medium and the formation of the weak “Dark energy”. Complex of magnetic particles, the quark magnetic dipoles and magneton by means of which the interconversion of a proton and a neutron is realized and maintained their constant number in the atomic nuclei can be called as magnetic meson. Namely, a processes of interconversion between a neutron and a proton which, as a rule, are not accompanied by secretions, created the illusion of neutron stability in atomic nuclei. The energy created by an exchange of magnetic mesons between neutron and proton can be a component of nuclear forces (strong interaction). Another effective and, most likely, the main component in the composition of the nuclear forces is the gravitational “Dark Energy”. Physics and structure of neutrinos presented in the paper suggest that the nature of these particles closer to the ideology of E. Majorana than P. Dirac’s. 展开更多
关键词 magnetic and Electric CHARGES Antielectrons Magnetons Antimagnetons Bispinor Physical Mass Vortex Electromagnetic (Gravitational) field QUARKS PROTONS Neutrons Positrons NEUTRINO MESONS weak and Strong Interactions “Dark Energy”
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星载材料极弱剩磁测量方法研究
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作者 孟立飞 徐超群 +4 位作者 陈金刚 肖琦 刘超波 周斌 张铁龙 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第8期1514-1519,共6页
为解决科学探测卫星星载材料微弱磁性测量难题,本文提出了一种卫星部件极弱剩磁的测量方法,并研制了测量系统。利用屏蔽技术去除外界磁场干扰,在屏蔽系统内搭建了测量系统,使用零场原子磁力仪采集旋转试件的磁场频谱信息,通过小波多分... 为解决科学探测卫星星载材料微弱磁性测量难题,本文提出了一种卫星部件极弱剩磁的测量方法,并研制了测量系统。利用屏蔽技术去除外界磁场干扰,在屏蔽系统内搭建了测量系统,使用零场原子磁力仪采集旋转试件的磁场频谱信息,通过小波多分辨分析方法处理得到试件的磁特征数据。研究表明:本文方法可有效提取极弱剩磁信号,且系统稳定度优于1×10^(-12) T/30 min,磁场分辨率优于1×10^(-12) T,磁矩提取分辨量级可达10^(-6) A·m^(2),为整星磁洁净控制和空间磁场高精度探测提供了途径。 展开更多
关键词 卫星 材料 极弱剩磁 磁屏蔽 测量系统 频谱 小波多分辨分析 磁洁净
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低频脉冲磁场诱导TRPC1改善COVID-19患者康复期下肢的肌肉无力症状 被引量:1
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作者 厉中山 包义君 +6 位作者 刘洁 孔维签 李伟 陈琳 白石 杨铁黎 王春露 《中国组织工程研究》 CAS 北大核心 2024年第16期2605-2612,共8页
背景:肌肉无力是新型冠状病毒(COVID-19)感染后的常见症状,影响康复期人体日常活动能力。在强度1.5 mT,频率3300 Hz的低频脉冲磁场刺激下可通过诱导和激活经典瞬时感受器电位通1(classical transient receptor potential channel 1,TRPC... 背景:肌肉无力是新型冠状病毒(COVID-19)感染后的常见症状,影响康复期人体日常活动能力。在强度1.5 mT,频率3300 Hz的低频脉冲磁场刺激下可通过诱导和激活经典瞬时感受器电位通1(classical transient receptor potential channel 1,TRPC1),提升人体骨骼肌的最大自主收缩力与力量耐力,对肌肉组织产生一系列生理支持效应,该手段是否会改善新型冠状病毒肺炎患者康复期的肌无力症状尚无研究。目的:选用低频脉冲磁场对新型冠状病毒肺炎患者下肢肌群进行磁刺激,以观察该刺激对新型冠状病毒肺炎患者康复期下肢肌群肌无力改善的影响。方法:招募胶体金法抗原检测试剂(COVID-19)为阳性并伴有肌肉无力症状的新型冠状病毒(奥密克戎毒株)感染患者14例,将所有受试者随机分成2组,分别为接受磁场刺激的试验组和接受假治疗的对照组。试验总时长3周,试验组每隔48 h对腿部进行低频脉冲磁刺激,对照组与试验组干预流程一致但给予假刺激,两组患者均不被告知磁刺激仪器是否运行,两组患者共进行9次操作,随后观察两组患者下肢局部肌群最大自主收缩力、腿部爆发力与力量耐力的变化情况。结果与结论:①在采集的8个局部肌群中,试验组患者7个局部肌群在经过3周的低频脉冲磁场刺激,最大自主收缩力值均增长。对照组除3个肌群最大自主收缩力自行增长改善以外,其他肌群肌力无提升。②试验组的左腿前群与双腿后群提升率显著高于对照组。③两组的纵跳摸高高度与膝关节峰值角速度相比试验前测均提升,试验组摸高高度提升率高于对照组。④在疲劳状态下,试验组膝关节峰值角速度下降率显著下降,对照组膝关节峰值角速度下降率无显著性变化;试验组摸高高度下降率显著下降,而对照组摸高高度下降率无显著性变化。⑤上述数据证实,在强度1.5 mT,频率3300 Hz的低频脉冲磁场刺激方案下,新型冠状病毒肺炎患者在康复期经过3周的低频脉冲磁场刺激相比人体自愈过程可使更多的下肢局部肌群肌力获得提升,对基于腿部爆发力的全身协调发力能力及功能状态明显改善。因此,低频脉冲磁场刺激可作为一种改善新冠感染患者下肢肌肉无力症状的有效、非运动的康复手段。 展开更多
关键词 新型冠状病毒 COVID-19 新型冠状病毒肺炎 脉冲磁场 经典瞬时感受器电位通道1 TRPC1 肌肉无力
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Chiral mesostructured hematite with temperature-independent magnetism due to spin confinement 被引量:1
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作者 Baiwen Zhang Jing Ai +3 位作者 Yingying Duan Te Bai Lu Han Shunai Che 《Nano Research》 SCIE EI CSCD 2024年第3期2019-2024,共6页
Hematite(α-Fe_(2)O_(3))is known to undergo conversion from weak ferromagnetic to antiferromagnetic as the temperature decreases below the Morin temperature(TM=250 K)due to spin moment rotation occurring during the Mo... Hematite(α-Fe_(2)O_(3))is known to undergo conversion from weak ferromagnetic to antiferromagnetic as the temperature decreases below the Morin temperature(TM=250 K)due to spin moment rotation occurring during the Morin transition(MT).Herein,we endowed hematite with mesostructured chirality to maintain weak ferromagnetism without MT.Chiral mesostructured hematite(CMH)nanoparticles were prepared by a hydrothermal method with glutamic acid(Glu)as the symmetry-breaking agent.The triangular bipyramidal CMH nanoparticles were composed of helically cleaved nanoflakes with twisted crystal lattice.Field-cooled(FC)magnetization measurements showed that the magnetic moments of CMH were stabilized without MT within the temperature range of 10–300 K.Hysteresis loop measurements confirmed the weak ferromagnetism of CMH.The enhanced Dzyaloshinskii–Moriya interaction(DMI)was speculated to be responsible for the temperature-independent weak ferromagnetism,in which the spin configuration would be confined with canted antiferromagnetic coupling due to the mesostructured chirality of CMH. 展开更多
关键词 hematite chiral mesostructure Dzyaloshinskii–Moriya interaction weak ferromagnetism antiferromagnetic material temperature-independent magnetism
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经颅直流电刺激–经颅磁刺激–音乐融合刺激对脑力疲劳干预效果的研究
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作者 任振峰 曹勇 +6 位作者 牟锴裕 王立志 王慧泉 张朋 王艳景 毕珣 姜昌华 《航天医学与医学工程》 CAS 2024年第2期105-111,共7页
目的评估经颅直流电刺激(tDCS)、经颅磁刺激(TMS)和音乐(Music)多物理场融合刺激方案对脑力疲劳的干预效果。方法疲劳诱发后,10名受试者分别接受空白(静息态)干预、音乐干预和tDCS-TMS-Music多物理场干预。tDCS刺激部位位于受试者双额区... 目的评估经颅直流电刺激(tDCS)、经颅磁刺激(TMS)和音乐(Music)多物理场融合刺激方案对脑力疲劳的干预效果。方法疲劳诱发后,10名受试者分别接受空白(静息态)干预、音乐干预和tDCS-TMS-Music多物理场干预。tDCS刺激部位位于受试者双额区,TMS刺激部位为后脑双侧枕部。每次刺激干预前后统计受试者主观疲劳量表、测定心率变异性和被试反应绩效,研究不同干预方案对脑力疲劳的缓解效果。结果与音乐组和空白组相比,tDCS-TMS-Music组干预后脑力负荷程度、反应绩效和心率变异性指标改善效果更好。结论tDCS-TMS-Music融合干预方案能够有效缓解长时间认知操作任务诱发的脑力疲劳,干预效果优于相同时间的音乐干预和静息态缓解。 展开更多
关键词 疲劳缓解 多物理场干预 微弱直流电刺激 弱磁场刺激
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Experimental studies on extremely low frequency pulsed magnetic field inhibiting sarcoma and enhancing cellular immune functions 被引量:8
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作者 张沪生 叶晖 +5 位作者 张传清 曾繁清 黄兴鼎 张晴川 李宗山 杜碧 《Science China(Life Sciences)》 SCIE CAS 1997年第4期392-397,共6页
The previous observation with an electron microscope showed that extremely low frequency (ELF) pulsed magnetic field (PMF) (with the maximum intensity of 0. 6-2. 0 T, gradient of 10-100 T. M-1, pulse width of 20-200 m... The previous observation with an electron microscope showed that extremely low frequency (ELF) pulsed magnetic field (PMF) (with the maximum intensity of 0. 6-2. 0 T, gradient of 10-100 T. M-1, pulse width of 20-200 ms and frequency of 0. 16-1. 34 Hz) inhibited the growth of S-180 sarcoma in mice and enhanced the ability of immune cell’s dissolving sarcoma cells. In this study, the DNA contents of nuclei were assayed by using Faulgen Staining method. With an electron microscope and cell stereoscopy technology it was observed that magnetic field affected the sarcoma cell’s metabolism, lowered its malignancy, and restrained its rapid and heteromorphic growth. The magnetic field enhanced the cellular immune ability and the reaction of lymphocytes and plasma. Since ELF pulsed magnetic fields can inhibit the growth of sarcomas and enhance the cellular immune ability, it is possible to use it as a new method to treat cancer. 展开更多
关键词 extremely low frequency (ELF) PULSED magnetic field cancer immunity.
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Effects of extremely low frequency magnetic field on anxiety level and spatial memory of adult rats 被引量:2
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作者 HE Li-hua SHI Hong-mei +3 位作者 LIUTong-tong XU Ying-chun YE Kang-ping WANG Sheng 《Chinese Medical Journal》 SCIE CAS CSCD 2011年第20期3362-3366,共5页
Background As the widespread use of electric devices in modern life, human are exposed to extremely low frequency magnetic fields (ELF MF) much more frequently than ever. Over the past decades, a substantial number ... Background As the widespread use of electric devices in modern life, human are exposed to extremely low frequency magnetic fields (ELF MF) much more frequently than ever. Over the past decades, a substantial number of epidemiological and experimental studies have demonstrated that ELF MF (50 Hz) exposure is associated with increased risk of various health effects. The present study examined the effects of chronic exposure to ELF MF on anxiety level and spatial memory of adult rats. Methods The 50-Hz ELF MF was used during the whole experimental procedures and the value of magnetic field (MF) was set to 2 mT. Adult rats were divided randomly to control, MF 1 hour and MF 4 hours group. Anxiety-related behaviors were examined in the open field test and the elevated plus maze; changes in spatial learning and memory were determined in Morris water maze aRer 4 weeks of daily exposure. Results Rats in MF 4 hours group had increased anxiety-like behaviors with unaltered locomotor activity. In the Morris water maze test, rats had reduced latency to find the hidden platform and improved long-term memory of former location of platform without changes in short-term memory and locomotor activity. Conclusion Chronic ELF MF exposure has anxiogenic effect on rats, and the promoting effects on spatial learning and long-term retention of spatial memory. 展开更多
关键词 extremely low frequency magnetic field ANXIETY spatial memory Morris water maze test open field test
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The Weak Magnetic Photon Emission from Quark-gluon Plasma
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作者 SUN Jing’an YAN Li 《原子核物理评论》 CAS CSCD 北大核心 2024年第1期558-563,共6页
There must be electromagnetic fields created during high-energy heavy-ion collisions.Although the electromagnetic field may become weak with the evolution of the quark-gluon plasma(QGP),compared to the energy scales o... There must be electromagnetic fields created during high-energy heavy-ion collisions.Although the electromagnetic field may become weak with the evolution of the quark-gluon plasma(QGP),compared to the energy scales of the strong interaction,they are potentially important to some electromagnetic probes.In this work,we propose the coupled effect of the weak magnetic field and the longitudinal dynamics of the background medium for the first time.We demonstrate that the induced photon spectrum can be highly azimuthally anisotropic when the quarkgluon plasma is in the presence of a weak external magnetic field.On the other hand,the weak magnetic photon emission from quark-gluon plasma only leads to a small correction to the photon production rate.After hydrodynamic evolution with a tilted fireball configuration,the experimentally measured direct photon elliptic flow is well reproduced.Meanwhile,the used time-averaged magnetic field in the hydrodynamic stage is found no larger than a few percent of the pion mass square. 展开更多
关键词 heavy-ion collision the direct photon weak magnetic field elliptic flow
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基于电子顺磁共振谱的残磁测量应用及进展
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作者 张全哲 邹升 张红 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第1期22-28,共7页
电子顺磁共振类似于核磁共振,是一种基于电子磁矩在外磁场中的顺磁性及塞曼分裂的方法,该方法与物质中未成对电子和外磁场相联系,通过获取和分析物质的电子顺磁共振谱,能够得到物质的结构信息或环境的磁场信息,因此其常被用来分析物质... 电子顺磁共振类似于核磁共振,是一种基于电子磁矩在外磁场中的顺磁性及塞曼分裂的方法,该方法与物质中未成对电子和外磁场相联系,通过获取和分析物质的电子顺磁共振谱,能够得到物质的结构信息或环境的磁场信息,因此其常被用来分析物质结构、探测磁场等。极弱磁场通常指nT或以下量级的磁场,目前一些科学研究的进行常常要求在极弱磁环境下进行,例如基础物理研究、心脑磁探测等,因此稳定可靠的磁屏蔽常被用来创建所需的极弱磁环境。磁屏蔽包括被动磁屏蔽和主动磁补偿,被动磁屏蔽指利用磁屏蔽室屏蔽外界磁场,其内部往往有一定量的残余磁场,因此为方便进一步主动磁补偿,探测屏蔽后的残余磁场是有必要的。目前屏蔽室内残余磁场的测量手段主要分为商用化磁强计测量和装置原位测量,商用化磁强计测量方法简单,但精度低、噪声大,且不利于小型化,利用装置原位测量能够减少噪声,是目前主要的研究方法。由于碱金属原子最外层含有一个未成对电子,其成为电子顺磁共振实验的理想样品。而随着激光和光泵技术的发展,利用法拉第旋光效应作为光学手段探测气体原子的电子顺磁共振谱已经成为了可能。通过测量碱金属原子气体的电子顺磁共振谱进行残余磁场的原位测量效果好、精度高,具有极大的应用前景。通常基于电子顺磁共振的残磁测量系统包括残磁环境和样品模块、光学探头模块、信号调制模块、环境监测模块以及信号收集与处理模块,核心是光学探头模块,决定了磁场测量的灵敏度。简要描述了电子顺磁共振技术的原理,以光泵磁力计为主介绍了基于该技术的典型磁力计和目前的发展,重点概述了基于电子顺磁共振谱的残磁测量系统、各个组成模块以及相关技术近年来的发展现状。 展开更多
关键词 电子顺磁共振 磁场传感 磁屏蔽 极弱磁环境
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Effect of a weak magnetic field on ductile-brittle transition in micro-cutting of single-crystal calcium fluoride 被引量:1
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作者 Yunfa Guo Yan Jin Lee +3 位作者 Yu Zhang Anastassia Sorkin Sergei Manzhos Hao Wang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第17期96-113,共18页
Magneto-plasticity occurs when a weak magnetic field alters material plasticity and offers a viable solution to enhance ductile-mode cutting of brittle materials.This study demonstrates the susceptibility of non-magne... Magneto-plasticity occurs when a weak magnetic field alters material plasticity and offers a viable solution to enhance ductile-mode cutting of brittle materials.This study demonstrates the susceptibility of non-magnetic single-crystal calcium fluoride(CaF_(2))to the magneto-plastic effect.The influence of magneto-plasticity on CaF_(2) was confirmed in micro-deformation tests under a weak magnetic field of 20 mT.The surface pile-up effect was weakened by 10-15 nm along with an enlarged plastic zone and suppressed crack propagation under the influence of the magnetic field.Micro-cutting tests along different crystal orientations on the(111)plane of CaF_(2) revealed an increase in the ductile-brittle transition of the machined surface with the aid of magneto-plasticity where the largest increase in ductile-brittle transition occurred along the[112]orientation from 512 nm to a range of 664-806 nm.Meanwhile,the subsurface damage layer was concurrently thinner under magnetic influence.An anisotropic influence of the magnetic field relative to the single-crystal orientation and the cutting direction was also observed.An analytical model was derived to determine an orientation factor M that successfully describes the anisotropy while considering the single-crystal dislocation behaviour,material fracture toughness,and the orientation of the magnetic field.Previously suggested theoretical mechanism of magneto-plasticity via formation of non-singlet electronic states in defected configurations was confirmed with density functional theory calculations.The successful findings on the influence of a weak magnetic field on plasticity present an opportunity for the adoption of magnetic-assisted micro-cutting of non-magnetic materials. 展开更多
关键词 Magneto-plasticity weak magnetic field Brittle material Ductile-brittle transition MICRO-CUTTING
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磁性纳米颗粒质量检测方法研究
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作者 常鑫茹 刘志勇 《农业装备与车辆工程》 2024年第5期117-119,共3页
提出一种基于亥姆霍兹线圈和TMR磁传感器的磁性纳米颗粒质量检测方法和装置,在匀强磁场下使用TMR磁传感器对不同质量的磁性纳米颗粒弱磁响应信号进行检测,分析磁响应信号随质量变化的趋势并绘制标准化曲线。结果表明:磁性纳米颗粒弱磁... 提出一种基于亥姆霍兹线圈和TMR磁传感器的磁性纳米颗粒质量检测方法和装置,在匀强磁场下使用TMR磁传感器对不同质量的磁性纳米颗粒弱磁响应信号进行检测,分析磁响应信号随质量变化的趋势并绘制标准化曲线。结果表明:磁性纳米颗粒弱磁响应信号同质量之间呈正相关函数关系。所提方法和装置为进一步研究磁性纳米颗粒用于免疫分析和单分子检测以获取其他相关信息提供了理论基础,具有良好的应用前景。 展开更多
关键词 磁性纳米颗粒 弱磁检测 亥姆霍兹线圈 TMR磁传感器
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