期刊文献+
共找到358篇文章
< 1 2 18 >
每页显示 20 50 100
The possible implications of magnetic field effect on understanding the reactant of water splitting 被引量:3
1
作者 Chao Wei Zhichuan J.Xu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第1期148-157,共10页
Electrochemical water splitting consists of two elementary reactions i.e.,hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).Developing robust HER and OER technologies necessitates a molecular picture ... Electrochemical water splitting consists of two elementary reactions i.e.,hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).Developing robust HER and OER technologies necessitates a molecular picture of reaction mechanism,yet the reactants for water splitting reactions are unfortunately not fully understood.Here we utilize magnetic field to understand proton transport in HER,and hydroxide ion transport in OER,to discuss the possible implications on understanding the reactants for HER and OER.Magnetic field is a known tool for changing the movement of charged species like ions,e.g.the magnetic‐field‐improved Cu^(2+)transportation near the electrode in Cu electrodeposition.However,applying a magnetic field does not affect the HER or OER rate across various pH,which challenges the traditional opinion that charged species(i.e.proton and hydroxide ion)act as the reactant.This anomalous response of HER and OER to magnetic field,and the fact that the transport of proton and hydroxide ion follow Grotthuss mechanism,collectively indicate water may act as the universal reactant for HER and OER across various pH.With the aid of magnetic field,this work serves as an understanding of water might be the reactant in HER and OER,and possibly in other electrocatalysis reactions involving protonation and deprotonation step.A model that simply focuses on the charged species but overlooking the complexity of the whole electrolyte phase where water is the dominant species,may not reasonably reflect the electrochemistry of HER and OER in aqueous electrolyte. 展开更多
关键词 ELECTROCATALYSIS water splitting magnetic field Lorenz force Metal deposition
下载PDF
Magnetic field‐enhanced water splitting enabled by bifunctional molybdenum‐doped nickel sulfide on nickel foam 被引量:2
2
作者 Yuanyuan Zhang Mengxin Chen +5 位作者 Ping Guo Yunchen Du Bo Song Xianjie Wang Zaixing Jiang Ping Xu 《Carbon Energy》 SCIE EI CAS CSCD 2023年第10期50-63,共14页
Herein,we report bifunctional molybdenum-doped nickel sulfide on nickel foam(Mo-NiS_(x)/NF)for magnetic field-enhanced overall water splitting under alkaline conditions.Proper doping of Mo can lead to optimization of ... Herein,we report bifunctional molybdenum-doped nickel sulfide on nickel foam(Mo-NiS_(x)/NF)for magnetic field-enhanced overall water splitting under alkaline conditions.Proper doping of Mo can lead to optimization of the electronic structure of NiS_(x),which accelerates the dissociation of H2O and the adsorption of OH−in the hydrogen evolution reaction(HER)and the oxygen evolution reaction(OER)processes,respectively.In addition,the magnetically active Mo-NiS_(x)/NF can further enhance the HER and OER activity under an applied magnetic field due to the magnetoresistance effect and the ferromagnetic(FM)exchange-field penetration effect.As a result,Mo-NiS_(x)/NF requires low overpotentials of 307 mV at 50mA cm^(−2)(for OER)and 136 mV at 10mA cm^(−2)(for HER)under a magnetic field of 10000 G.Furthermore,the electrolytic cell constructed by the bifunctional Mo-NiS_(x)/NFs as both the cathode and the anode shows a low cell voltage of 1.594 V at 10 mA cm^(−2)with optimal stability over 60 h under the magnetic field.Simultaneous enhancement of the HER and OER processes by an external magnetic field through rational design of electrocatalysts might be promising for overall water splitting applications. 展开更多
关键词 electron density modulation FM exchange‐field penetration effect magnetic field magnetoresistance effect water splitting
下载PDF
Magnetic field increase weight and water content in date palm (Phoenix dactylifera L.)
3
作者 Faten Dhawi Jameel M. Al-Khayri 《Journal of Agricultural Science and Technology》 2009年第1期23-29,共7页
Magnetic field effects on different plant species have been subject of many studies in the last decade. Magnetic fields are known to induce changes in plant metabolism, growth and productivity. In this study, effect o... Magnetic field effects on different plant species have been subject of many studies in the last decade. Magnetic fields are known to induce changes in plant metabolism, growth and productivity. In this study, effect of magnetic field on date palm weight and water content has been investigated. Seedlings of date palm were treated with two types of magnetic fields in two separate experiments. In the first experiment, seedlings were treated with static magnetic field SMF using electromagnetic circuit set to produce three levels of magnetic field intensities 10, 50 and 100 mT for different durations (0, 30, 60, 120, 180 and 240 min). In the second experiment seedlings were treated with alternating magnetic field AMF, using magnetic resonance imaging providing 1500 mT for 0, 1, 5, 10 and 15 min. After two months of exposure, plants growth parameters (fresh, dry weights and water content for both leaves and roots) were recorded. The measurements revealed that leaf fresh, dry weight and water content increased significantly in response to SMF treatment. Similarly, roots fresh weight and water content were increased significantly; however roots dry weight increasing were insignificant. In the second experiment, AMF has affected plant growth all parameters were increased significantly. Measurements reached the highest level at 15 min of exposure. This study revealed that magnetic fields affect date palm growth parameters by increasing osmotic pressure and water potential which increase water absorption and enhance flesh weight. 展开更多
关键词 date palm dry weight fresh weight LEAF magnetic field ROOT water content
下载PDF
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
4
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
下载PDF
Separation of Fe<sub>3</sub>O<sub>4</sub>Nanoparticles from Water by Sedimentation in a Gradient Magnetic Field
5
作者 I. Medvedeva Iu. Bakhteeva +6 位作者 S. Zhakov A. Revvo M. Uimin A. Yermakov I. Byzov A. Mysik N. Shchegoleva 《Journal of Water Resource and Protection》 2015年第2期111-118,共8页
Sedimentation dynamics of magnetite (γ-Fe3O4) nanopowders (10 - 20 nm) in water in the presence of a gradient magnetic field was studied by optical and Nuclear Magnetic Resonance (NMR) relaxometry methods. The magnet... Sedimentation dynamics of magnetite (γ-Fe3O4) nanopowders (10 - 20 nm) in water in the presence of a gradient magnetic field was studied by optical and Nuclear Magnetic Resonance (NMR) relaxometry methods. The magnetic field B ≤ 0.3 T, dB/dz ≤ 0.13 T/cm was produced by the system of permanent strip magnets. The initial sedimentation rate of the nanoparticles in water and under magnetic fields is higher for less concentrated suspensions (c0 = 0.1 g/l) than for more concentrated ones (c0 = 1 g/l). This might be connected with the formation of gel structures due to strong magnetic attraction between ferromagnetic nanoparticles. In the gravitation field, the suspensions of the particles (10 - 20 nm) remain stable for over 20 hours. The sedimentation process can be greatly accelerated by the action of a vertical gradient magnetic field, reducing the sedimentation time down to several minutes. In a gradient magnetic field enhanced by a steel grid, sedimentation of the nanopowder (c0 = 0.1 g/l) for 180 minutes resulted in reduction of the iron concentration in water down to 0.4 mg/l. In flowing water regime, the residual iron concentration in water 0.3 mg/l is reached after 80 minutes. 展开更多
关键词 MAGNETITE NANOPARTICLES water SEDIMENTATION Gradient magnetic field
下载PDF
Magnetic Field Enhancement in Ammonia-Water Absorption Refrigeration Systems
6
作者 Moradeyo K. Odunfa Richard O. Fagbenle +1 位作者 Olanrewaju M. Oyewola Olayinka S. Ohunakin 《Energy and Power Engineering》 2014年第4期54-68,共15页
Absorption enhancement has been considered as an effective way of improving coefficient of performance (COP) of refrigeration systems and magnetic enhancement is one of these methods. A model of magnetic field enhance... Absorption enhancement has been considered as an effective way of improving coefficient of performance (COP) of refrigeration systems and magnetic enhancement is one of these methods. A model of magnetic field enhancement in ammonia-water absorption systems is presented in this paper. A numerical model using finite difference scheme was developed based on the conservation equations and mass transport relationship. Macroscopic magnetic field force was introduced in the momentum equation. The model was validated using data obtained from the literature. Changes in the physical properties of ammonia solution while absorbing both in the direction of falling film and across its thickness were investigated. The magnetic field was found to have some positive effect on the ammonia-water falling film absorption. The results indicate that absorption performance enhancement increased with magnetic intensity. The COP of simple ammonia solution absorption refrigeration system increased by 1.9% and 3.6% for magnetic induction of 1.4 and 3.0 Tesla respectively. 展开更多
关键词 AMMONIA-water Absorption REFRIGERATION magnetic field Force AMMONIA SOLUTION Concentration COEFFICIENT of Performance Finite DIFFERENCE Scheme Numerical SOLUTION
下载PDF
Effects of alternating magnetic field on the corrosion rate and corrosion products of copper 被引量:10
7
作者 GUO Bin ZHANG Peng +1 位作者 JIN Yongping CHENG Shukang 《Rare Metals》 SCIE EI CAS CSCD 2008年第3期324-328,共5页
The effects of alternating magnetic field on the corrosion morphologies, corrosion rate, and corrosion products of copper in 3.5% NaCl solution, sea water, and magnetized sea water were investigated using electrochemi... The effects of alternating magnetic field on the corrosion morphologies, corrosion rate, and corrosion products of copper in 3.5% NaCl solution, sea water, and magnetized sea water were investigated using electrochemical test, scanning electron microscopy/energy dispersive analysis system of X-ray (SEM/EDAX), and X-ray diffraction (XRD). The results show that the corrosion rate of copper in magnetized sea water is minimal. Moreover, the surface of the specimen in magnetized sea water is uniform and compact as compared with those in 3.5% NaCl solution and sea water. The corrosion products of copper in magnetized sea water are mainly Cu2O and CuCl2. However, the corrosion products in sea water are CuCl, Cu2Cl(OH)3, and FeCl3-6H2O. The electrochemical corrosion mechanisms of copper in the three media were also discussed. 展开更多
关键词 CORROSION sea water alternating magnetic field COPPER corrosion products
下载PDF
Investigation of changes in properties of water under the action of a magnetic field 被引量:23
8
作者 PANG XiaoFeng1,2 & DENG Bo1 1 Institute of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China 2 International Centre for Materials Physics, Chinese Academy of Sciences, Shenyang 110015, China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2008年第11期1621-1632,共12页
The properties of water and their changes under the action of a magnetic field were gathered by the spectrum techniques of infrared, Raman, visible, ultraviolet and X-ray lights, which may give an insight into molecul... The properties of water and their changes under the action of a magnetic field were gathered by the spectrum techniques of infrared, Raman, visible, ultraviolet and X-ray lights, which may give an insight into molecular and atomic structures of water. It was found that some properties of water were changed, and a lot of new and strange phenomena were discovered after magnetization. Magnetized water really has magnetism, which has been verified by a peak shift of X-ray diffraction of magnetized water + Fe3O4 hybrid relative to that of pure water + Fe3O4 hybrid, that is a saturation and memory effect. The properties of infrared and ultraviolet absorptions, Raman scattering and X-ray diffraction of magnetized water were greatly changed relative to those of pure water; their strengths of peaks were all increased, the frequencies of some peaks did also shift, and some new peaks, for example, at 5198, 8050 and 9340 cm?1, occurred at 25°C after water was magnetized. In the meanwhile, the magnetized effects of water are related to the magnetized time, the intensity of an externally applied magnetic field, and the temperature of water, but they are not a linear relationship. The study also showed a lot of new and unusual properties of magnetized water, for example, the six peaks in 3000–3800 cm?1 in infrared absorption, the exponential increase of ultraviolet absorption of wave with the decreasing wavelength of light of 200–300 nm, the frequency-shifts of peaks, a strange irreversible effect in the increasing and decreasing processes, as well as a stronger peak of absorption occurring at 50°C, 70°C and 80°C, the existence of many models of motion from 85°C to 95°C in 8000–10000 cm?1, and so on. These results show that the molecular structure of water is very complicated, which needs further study. Furthermore, the macroscopic feature of mechanics, for instance, surface tension force of magnetized water, was also measured. Experiments discovered that the size in contact angles of magnetized water on the surface of hydrophobic materials decreases, thus the surface tension force of magnetized water decreases relative to that of pure water. It is seen from the above results that the clustering structure of hydrogen-bonded chains and polarization effects of water molecules are enhanced after magnetization. These results are helpful in revealing the mechanism of magnetization of water. 展开更多
关键词 pure water magnetized water magnetic-field physical property spectrum SATURATION and memory effect mechanical feature surface tension force polarization ANGLES of contact
原文传递
Variations of optic properties of water under action of static magnetic field 被引量:2
9
作者 DENG Bo PANG XiaoFeng 《Chinese Science Bulletin》 SCIE EI CAS 2007年第23期3179-3182,共4页
Effects of static magnetic field on optic properties of water are investigated by infrared spectroscopy, ultraviolet spectroscopy and X-ray diffraction, respectively. The ultraviolet spectroscopy experiments show the ... Effects of static magnetic field on optic properties of water are investigated by infrared spectroscopy, ultraviolet spectroscopy and X-ray diffraction, respectively. The ultraviolet spectroscopy experiments show the changes of properties of water under action of static magnetic field, in the region of 191 to 400 nm. The infrared experiment shows that the water exposed in a magnetic field had saturation and memory effects. The magnetized effects increased with increasing exposed time, but were weakened with increasing of time when the magnetic field was removed. In the X-ray experiment, the strength of diffraction increased also, after the water was exposed in magnetic field. Meanwhile, the shift of peak and increase of strength of X-ray diffraction of magnetized water added with nanoFe3O4 occurred as compared with that of pure water added with nano Fe3O4. This result suggests that the magnetized wa- ter has certain magnetism. Finally, these phenomena are simply explained by the molecular structure of water and the theory of magnetization of water. 展开更多
关键词 红外线光谱学 紫外线光谱学 X衍射 静力学 磁铁
原文传递
Flow Field and Temperature Field of Water-Cooling-Type Magnetic Coupling 被引量:2
10
作者 Lei Wang Zhenyuan Jia +1 位作者 Yuqin Zhu Li Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第4期61-72,共12页
At present, the water-cooling simulation of the water-cooled magnetic coupler is based on the water-cooled motor and the hydraulic coupler, which cannot accurately characterize the temperature distribution of the rota... At present, the water-cooling simulation of the water-cooled magnetic coupler is based on the water-cooled motor and the hydraulic coupler, which cannot accurately characterize the temperature distribution of the rotating watercooled coupling of the coupler. Focusing on rotating water cooling radiating, the present paper proposes simulating the water cooling temperature field as well as the flow field through the method of combining fluid-solid coupled heat transfer and MRF(Multiphase Reference Frame). In addition, taking an 800 kW magnetic coupling as an example, the paper optimizes the shape, number, cooling water inlet speed? and so on? of the cooling channel. Considering factors such as the complete machine’s temperature, and drag torque, it is proved that the cooling e ect is best when there are 36 involute curved channels and when the inlet speed is 3 m/s. Further, through experiments, the actual temperature values at six di erent positions when 50 kW and 70 kW thermal losses di er are measured. The measured values agree with the simulation results, proving the correctness of the proposed method. Further, data have been collected during the entire experimental procedure? and the variation in the coupling’s temperature is analyzed in depth, with the objective of laying a foundation for the estimation of the inner temperature rise as well as for the optimization of the structural design. 展开更多
关键词 water-cooling magnetic COUPLING Fluid-solid COUPLING Channel Three-dimensional TEMPERATURE field
下载PDF
Effects of extremely low frequency magnetic field on anxiety level and spatial memory of adult rats 被引量:2
11
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
原文传递
ARSENIC REMOVAL BY SULFIDATION SEDIMENTATION IN MAGNETIC FIELD
12
作者 Ma, Wei Ma, Wenji +1 位作者 Ma, Rongjun Shen, Dianbang 《中国有色金属学会会刊:英文版》 EI CSCD 1998年第3期174-177,共4页
1INTRODUCTIONAsthewatersourcecrisisisbecomingmoreandmoresevereandtheenvironmentprotectionrequirementsarebeco... 1INTRODUCTIONAsthewatersourcecrisisisbecomingmoreandmoresevereandtheenvironmentprotectionrequirementsarebecomingmoreandmoreri... 展开更多
关键词 ARSENIC treatment of waste water SULFIDE magnetic field
下载PDF
Magnetically Treated Irrigation Water Improves the Production and the Fruit Quality of Strawberry Plants(Fragaria×ananassa Duch.)in the Northwest of Morocco
13
作者 Houda Taimourya Mohamed Oussible +4 位作者 Lahoussaine Baamal El Hassane Bourarach Najem Hassanain Lhoussaine Masmoudi Abderrahmane El Harif 《Journal of Agricultural Science and Technology(B)》 2018年第3期145-156,共12页
Utilization of magnetically treated water has been investigated and applied in many countries such as Russia,Australia,Israel,China and Japan.Studies have shown that the magnetic field is used as a safe alternative to... Utilization of magnetically treated water has been investigated and applied in many countries such as Russia,Australia,Israel,China and Japan.Studies have shown that the magnetic field is used as a safe alternative to improve plant growth and development.Although the properties of magnetically treated water have received a great deal of interest in recent years,there are no studies conducted in Moroccan agricultural conditions.The present study aimed at gaining more insight on the effect of magnetically treated irrigation water(MTIW)in the northwest region of Morocco,on the yield of strawberry plants(Fragaria×ananassa Duch.cv.Camarosa)and its components.The experiments were conducted in situ,during two crop seasons(2011-2012 and 2013-2014).The results confirm that physical treatment of irrigation water by a static magnetic field improves the yield and quality of strawberry fruits.The percentages of increase in number of flowers,number of fruits,fruit yield and quality of export production per 100 plants were 27.4%,30.9%,34.8%,24.3%,respectively,compared with normal irrigation water(average over both crop seasons).These results suggest that irrigation with MTIW improves the production as well as the quality of the strawberry fruit,thus water use efficiency was enhanced.Therefore,the MTIW can be considered as a promising technique for improvement but extensive research is still required. 展开更多
关键词 magnetic field irrigation water STRAWBERRY PRODUCTION quality
下载PDF
The Gravito-Chemical Bond and Structures of Hydrocarbons and Water Molecules with Real Magnetic Charges
14
作者 Robert A. Sizov 《Open Journal of Physical Chemistry》 2021年第4期220-240,共21页
Experimental and theoretical studies of the author (period: 1968-present) have shown that true sources of </span><span style="font-family:"">the </span><span style="font-family... Experimental and theoretical studies of the author (period: 1968-present) have shown that true sources of </span><span style="font-family:"">the </span><span style="font-family:"">magnetic field are magnetic fundamental particles (magnetic charges), and not moving electrons. The main reason for <span>ignoring real magnetic charges, as well as true antielectrons in physical</span> science is the hard conditions for confinement of these particles in atoms and substance</span><span style="font-family:"">s</span><span style="font-family:"">, which </span><span style="font-family:"">is </span><span style="font-family:"">radically different from the confinement of electrons. Magnetic charges together with electric charges form the shells atoms which are <span>electromagnetic, and not electronic. Namely</span></span><span style="font-family:"">,</span><span style="font-family:""> electromagnetic shells are</span><span style="font-family:""> sources of gravitational field which is </span><span style="font-family:"">a </span><span style="font-family:"">vortex electromagnetic field and de<span>scribed by the vortex</span></span><span style="font-family:""> rot [<i>E</i> - <i>H</i>]</span><span style="font-family:"">. Depending on the state polarization o</span><span style="font-family:"">f vortex vectors </span><span style="font-family:"">rot [<i>E</i> - <i>H</i>]</span><span style="font-family:""> in compositions of atomic gravitational fields it </span><span style="font-family:"">is </span><span style="font-family:"">subdivided into paragravitational (PGF) and ferrogravitational fields </span><span style="font-family:"">(FGF). The overwhelming number of atoms emits PGF. Between the masses (bodies, atoms, nucleons and others) emitting PGF areas of negative gravitational “Dark Energy” are realized the forces of which press the masses towards each other. Namely</span><span style="font-family:"">,</span><span style="font-family:""> the compression of atoms by the forces of paragravitational “Dark Energy” underlies the chemical bond. The exception here is the ionic bond in ionic crystals. However, all ions have electromagnetic shells that generate the gravitational field. Consequently, ionic bonding is a relatively rare addition to gravito-chemical bond processes. The direct gravito-chemical bond of carbon atom</span><span style="font-family:"">s</span><span style="font-family:""> with hydrogen (<sup>1</sup>H) is physically forbidden due to </span><span style="font-family:"">the </span><span style="font-family:"">manifestation of the effect of ferrogravitational levitation between them and the repulsion of atoms from each other. Paradoxically, but all existing ideas about the structural device of hydrocarbons are based on such physically forbidden bonds which, moreover, must be realized through ionic <span>bonds which in reality do not exist. Chemical bonding of carbon and hydrogen </span>atoms to form hydrocarbons molecules is possible only if the hydrogen atoms are in the molecular form (<sup>1</sup>H<sub>2</sub>). In the composition of water, within the framework of the chemical formula H<sub>2</sub>O, two stable isomorphic molecular structures are formed. The chemical bond in the first structure is similar to the hydrocarbon scenario described above, </span><span style="font-family:""><i></span><i><span style="font-family:"">i.e.</span></i><i><span style="font-family:""></i></span></i><span style="font-family:""> in the process of combining paragravitational oxygen with a hydrogen molecule <sup>1</sup>H<sub>2</sub>. The second molecular structure in water is <span>formed under conditions of ferropolarization of the gravitational field of</span> oxygen atom</span><span style="font-family:"">s</span><span style="font-family:""> under the influence of FGF of neighboring <sup>1</sup>H atoms. In this case, the chemical bond is realized under the conditions of ferropolarization</span><span style="font-family:""> </span><span style="font-family:"">of the vortex vectors </span><span style="font-family:"">rot [<i>E</i> - <i>H</i>]</span><span style="font-family:""> of the gravitational fields of all atoms in</span><span style="font-family:""> the molecule and the co-directionality of them vectors </span><span style="font-family:""><i></span><b><i><span style="font-family:"">P</span></i></b><i><sub><span style="font-family:"">fp</span></sub></i><i><sub><span style="font-family:""></i></span></sub></i><span style="font-family:""> ferropolarization. The gravito-physical properties of the presented molecular structures in the composition of water make it possible to name them, respectively, as heavy and light clusters. 展开更多
关键词 magnetic Charges True Antielectrons S-Gravitons Gravitational field Ferro- and Paragravitation Gravitational Levitation Gravito-Chemical Bond Hydrocarbon and water Molecules Heavy and Light the water Clusters
下载PDF
掺硫铝酸钙类膨胀剂白水泥净浆干燥收缩与水分损失关联
15
作者 梁华明 朱文彬 +2 位作者 郭鑫志 卢艺菲 周春圣 《哈尔滨工业大学学报》 EI CAS 北大核心 2025年第1期140-148,共9页
为精确解析干燥条件下掺硫铝酸钙类膨胀剂水泥基材料的收缩行为,深入揭示低相对湿度条件下硫铝酸钙类膨胀剂补偿收缩效果下降的机制,利用低场磁共振弛豫技术,结合X射线衍射、质量与长度测试,在不同相对湿度下对掺与不掺硫铝酸钙类膨胀... 为精确解析干燥条件下掺硫铝酸钙类膨胀剂水泥基材料的收缩行为,深入揭示低相对湿度条件下硫铝酸钙类膨胀剂补偿收缩效果下降的机制,利用低场磁共振弛豫技术,结合X射线衍射、质量与长度测试,在不同相对湿度下对掺与不掺硫铝酸钙类膨胀剂白水泥净浆的干燥收缩历程进行10个月的长期监测,从含水量及水分状态角度,定量描述白水泥净浆干燥失水和收缩的演变规律,阐明硫铝酸钙类膨胀剂导致干燥收缩落差增大的作用机制。结果表明:在相对湿度为75%、43%、11%的环境中干燥,白水泥净浆失水量和干燥收缩均持续增大直至稳定,3类环境中各试件干燥收缩与相对失水量间的关系基本保持一致;随干燥时间延长,单位失水量导致的干燥收缩先降低后升高,干燥进程中净浆内部各级孔隙失水规律不同,且各湿度条件下的干燥收缩机制存在差异;掺入硫铝酸钙类膨胀剂后,C-S-H凝胶纳米孔结构会发生一定粗化,干燥时易损失更多可蒸发水,且膨胀剂水化生成的钙矾石还会损失2~5个结晶水,二者共同导致净浆水分损失与干燥收缩增大;在低湿度环境中应用硫铝酸钙类膨胀剂时,需注意这两个因素导致收缩落差增大的影响。 展开更多
关键词 白水泥 硫铝酸钙类膨胀剂 干燥收缩 水分损失 低场磁共振
下载PDF
MHD Free Convective Flow of Water near 4℃ past a Vertical Moving Plate with Constant Suction 被引量:1
16
作者 Michalis Xenos Stelios Dimas Andreas Raptis 《Applied Mathematics》 2013年第1期52-57,共6页
The aim of this work is the study of the magnetohydrodynamic (MHD) unsteady free convective flow of water near 4℃ past an infinitely vertical plate moving with constant velocity. The influence of constant uniform suc... The aim of this work is the study of the magnetohydrodynamic (MHD) unsteady free convective flow of water near 4℃ past an infinitely vertical plate moving with constant velocity. The influence of constant uniform suction was also considered. The partial differential equations (PDEs) and their initial and boundary conditions, describing the problem under consideration, are dimensionalized and the numerical solution is obtained by using the finite volume discretization methodology which is suitable for Fluid Mechanics applications. The numerical results for the velocity and temperature fields are shown in figures for different dimensionless parameters entering in the problem under consideration, such as the magnetic parameter, M and the Grashof number, Gr. This study predicts the effects of a constant magnetic field and uniform suction on the free convective flow of water near 4℃, when the water is electrically conductive. Analysis of the results showed that the velocity and temperature profiles are noticeably influenced by these parameters. 展开更多
关键词 Free Convection water near 4℃ Constant magnetic field Finite Volume Method
下载PDF
磁场辅助冻结对汤圆粉团品质的影响
17
作者 潘治利 申佳晋 +3 位作者 雷萌萌 艾志录 杨联芝 黄忠民 《中国食品学报》 EI CAS CSCD 北大核心 2024年第3期139-148,共10页
目的:为了探究磁场辅助冻结对汤圆粉团冻结品质的影响,开发新型辅助冻结方式在米面制品上的应用,研究不同磁场强度下辅助冻结对汤圆粉团品质变化。方法:采用平板冻结加磁场辅助的方式冷冻汤圆粉团,测定汤圆粉团冻结速率、失水率、色度... 目的:为了探究磁场辅助冻结对汤圆粉团冻结品质的影响,开发新型辅助冻结方式在米面制品上的应用,研究不同磁场强度下辅助冻结对汤圆粉团品质变化。方法:采用平板冻结加磁场辅助的方式冷冻汤圆粉团,测定汤圆粉团冻结速率、失水率、色度、质构特性、糊化特性、可冻结水含量和水分结合状态等指标,揭示磁场辅助冻结对其品质的影响。结果表明,与对照组相比较,经磁场辅助冻结后汤圆粉团冻结速率、失水率、色度、质构特性、糊化特性和可冻结水含量等均存在显著性差异(P<0.05)。磁场辅助冻结的汤圆粉团在24 Gs时冻结速率加快,进入最大冰晶生成带时间提前4 min,使得冰晶体积变小;失水率降低了37.57%,亮度提高了3.63%,透光度提高了14.92%和硬度下降了11.74%。从水分结合状态上看,汤圆粉团的可冻结水含量明显低于对照组,在24 Gs时降低了11.64%;然而,磁场辅助冻结后汤圆粉团的峰值黏度增加7.81%,回生值增加3.93%;水分结合状态上未见显著性差异。结论:在磁场强度为24 Gs时汤圆粉团的冻结品质最佳,可明显改善汤圆粉团的失水率、色度、硬度、可冻结水含量等品质指标。研究结果为磁场辅助冻结在米面制品上的应用提供了参考。 展开更多
关键词 磁场 汤圆粉团 水分结合状态 品质变化
下载PDF
马蹄脆片微波真空干燥工艺优化及其水分变化 被引量:1
18
作者 谭德馨 唐小闲 +4 位作者 张奕涛 李官丽 黎小椿 罗杨合 伍淑婕 《食品研究与开发》 CAS 2024年第3期107-115,共9页
以马蹄为原料,采用微波真空干燥技术干燥马蹄脆片,考察微波功率、干燥温度、真空度、切片厚度对马蹄脆片色差值、总糖含量、脆度的影响,以响应面试验优化干燥工艺,采用低场核磁共振技术研究马蹄脆片干燥过程水分变化情况。结果表明,微... 以马蹄为原料,采用微波真空干燥技术干燥马蹄脆片,考察微波功率、干燥温度、真空度、切片厚度对马蹄脆片色差值、总糖含量、脆度的影响,以响应面试验优化干燥工艺,采用低场核磁共振技术研究马蹄脆片干燥过程水分变化情况。结果表明,微波真空干燥马蹄脆片的最佳工艺为微波功率2.0 kW、干燥温度71℃、真空度-95 kPa、切片厚度3.1 mm,所得产品色差值、总糖含量、脆度分别为3.42、50.51 mg/100 g、464.96 g,产品色泽白亮,酥脆可口,马蹄风味浓厚。低场核磁共振检测结果表明:马蹄片内部主要存在3种状态水,分别是自由水、不易流动水及结合水,其中自由水占比较高、结合水和不易流动水的比例相对较低,在最佳工艺下到达干燥终点时自由水完全除去,只剩少量的不易流动水以及结合水。 展开更多
关键词 马蹄脆片 微波真空干燥 水分变化 工艺优化 低场核磁共振
下载PDF
鲜湿甘薯渣水分相态分布测定及其束水机制分析
19
作者 张欢欢 高飞虎 +5 位作者 张玲 钟巍然 杨世雄 李雪 张雪梅 梁叶星 《食品科学》 EI CAS CSCD 北大核心 2024年第19期1-7,共7页
为探究鲜湿甘薯渣的束水机理,以10种不同品种鲜湿甘薯渣为研究对象,采用低场核磁共振仪测定鲜湿甘薯渣中水分的相态分布,分析甘薯渣各相态水分与主要有机非水组分之间的相关性,再结合酶解实验进行因果关系验证。结果表明:10种鲜湿甘薯... 为探究鲜湿甘薯渣的束水机理,以10种不同品种鲜湿甘薯渣为研究对象,采用低场核磁共振仪测定鲜湿甘薯渣中水分的相态分布,分析甘薯渣各相态水分与主要有机非水组分之间的相关性,再结合酶解实验进行因果关系验证。结果表明:10种鲜湿甘薯渣中存在3~4种相态的水分,分别命名为组成水(T_(21),0.658~2.310 ms)、固定化水(T_(22),7.055~21.550 ms)、滞化水(T_(23),377.410~705.480 ms)和自由流动水(T_(24),705.480~3764.936 ms);鲜湿甘薯渣中滞化水含量最高,平均占比93.59%,固定化水含量次之,平均占比5.15%,组成水和自由流动水含量较少,分别占比0.85%、0.41%;鲜湿甘薯渣中主要相态水分滞化水与果胶、膳食纤维和不溶性膳食纤维含量呈显著正相关;鲜湿薯渣经果胶酶水解后可排出水量显著增加,而经纤维素酶、半纤维素酶和木质素过氧化物酶酶解后的薯渣可排出水量无明显变化;扫描电子显微镜观察到大部分淀粉颗粒被包裹或束缚于细胞壁碎片中。此研究可为甘薯渣高效脱水技术的开发提供理论依据。 展开更多
关键词 鲜湿甘薯渣 低场核磁共振 水分相态分布 束水机理
下载PDF
矿井瞬变电磁透视探测技术响应特征研究与应用
20
作者 李毛飞 姜志海 +4 位作者 刘树才 童雪瑞 陈尚斌 高兆丰 代琦 《煤炭学报》 EI CAS CSCD 北大核心 2024年第4期1976-1988,共13页
针对大采长/超宽工作面内部隐蔽地质异构体常规地球物理探测难的问题,揭示了对侧发射接收的瞬变电磁透视探测电磁响应机制。采用理论研究、数值模拟和实测数据分析相结合的研究方式,对瞬变电磁透视探测技术电磁场扩散特征、数据影响机... 针对大采长/超宽工作面内部隐蔽地质异构体常规地球物理探测难的问题,揭示了对侧发射接收的瞬变电磁透视探测电磁响应机制。采用理论研究、数值模拟和实测数据分析相结合的研究方式,对瞬变电磁透视探测技术电磁场扩散特征、数据影响机制以及探测能力进行了详细研究,研究结果表明:受地空边界的影响,全空间长条形发射回线瞬态电磁场扩散与半空间电磁场扩散不同,全空间状态下感应电动势极值长期位于发射线圈中心位置,无法直接沿用地面“烟圈效应”进行处理解释;对侧发射接收的瞬变电磁透视早期数据主要受一次磁场的影响,具有较高的左右低阻异常分辨能力和探测能力,晚期数据与同侧发射接收数据产生机制相同,为发射线圈附近产生的二次场相互感应扩散形成,其分辨能力和探测能力相对较弱;相较于同侧发射接收的瞬变电磁法,对侧发射接收的瞬变电磁透视技术结合早晚期数据,可以很好的区分低阻异常体相对于发射线圈和接收点的空间位置;低阻异常体越靠近发射线圈,对侧接收的早期数据受到的影响越大,晚期数据影响时间段有所增加,但影响程度越小,越靠近接收点所在巷道,其影响特征相反,以此可以粗略判断低阻异常体沿工作面切向的位置。早晚期数据相结合的瞬变电磁透视探测技术,能更加精细地解译工作面内部及附近隐蔽突水地质异构体的空间信息。 展开更多
关键词 瞬变电磁透视 大采长工作面 一次磁场 感应磁场 水害防治
下载PDF
上一页 1 2 18 下一页 到第
使用帮助 返回顶部