I. Lithium-ion battery The lithium-ion battery is a secondary battery, which mainly relies on lithium ions moving between the positive and negative electrodes to work. During the charging and discharging process, lithium ions are embedded and de-embedded back and forth between the two electrodes through the diaphragm, and the storage and release of lithium-ion energy are achieved through the redox reaction of the electrode material. Lithium-ion battery mainly consists of positive electrode material, diaphragm, negative electrode material, electrolyte, and other materials. Among them, the diaphragm in the lithium-ion battery plays a role in preventing direct contact between the positive and negative electrodes, and allows the free passage of lithium ions in the electrolyte, providing a microporous channel for lithium ion transport. The pore size, degree of porosity, uniformity of distribution, and thickness of the lithium-ion battery diaphragm directly affect the diffusion rate and safety of the electrolyte, which has a great impact on the performance of the battery. If the pore size of the diaphragm is too small, the permeability of lithium ions is limited, affecting the transfer performance of lithium ions in the battery, and making the battery resistance increases. If the aperture is too large, the growth of lithium dendrites may pierce the diaphragm, causing accidents such as short circuits or explosions. Ⅱ. The application of field emission scanning electron microscopy in the detection of lithium diaphragm The use of scanning electron microscopy can observe the pore size and distribution uniformity of the diaphragm, but also on the multi-layer and coated diaphragm cross-section to measure the thickness of the diaphragm. Conventional commercial diaphragm materials are mostly microporous films prepared from polyolefin materials, including polyethylene (PE), polypropylene (PP) single-layer films, and PP/PE/PP three-layer composite films. Polyolefin polymer materials are insulating and non-conductive, and are very sensitive to electron beams, which can lead to charging effects when observed under high voltage, and the fine structure of polymer diaphragms can be damaged by electron beams. The SEM5000 field emission scanning electron microscope, which is independently developed by GSI, has the capability of low voltage and high resolution, and can directly observe the fine structure of the diaphragm surface at low voltage without damaging the diaphragm. The diaphragm preparation process is mainly divided into two types of dry and wet methods. The dry method is the melt stretching method, including the unidirectional stretching process and bidirectional stretching process, the process is simple, has low manufacturing costs, and is a common method of lithium-ion battery diaphragm production. The diaphragm prepared by the dry method has flat and long microporous (Figure 1), but the prepared diaphragm is thicke...
View MoreQuantum technology has been developed and popularized, eventually bringing human society into the quantum era. On December 22, 2020, Xishan Senior High School in Jiangsu, China officially started the "Quantum Computing Theory and Experiment" course based on CIQTEK Diamond Quantum Computer for Education. This is the first time quantum computing has been introduced into Chinese primary and secondary schools, and it is another breakthrough for the quantum computing industry. Dr. Ming Chen from CIQTEK was explaining quantum computing to the students "The first channel is the laser, the third channel is the measurement, you need to pay attention to the state of each channel." Under the guidance of Dr. Ming Chen from CIQTEK, the students conducted Rabi oscillation experiments using the "Diamond Quantum Computing Teaching Machine". The students said, "It was fun to do quantum computing experiments with my classmates! This class allowed me to be exposed to cutting-edge technology during my high school years, which laid the foundation for my future major choice." Unlike Newton's classical theory, which emphasizes "certainty", "mechanics", and "uniqueness", quantum theory emphasizes "unmeasured ", "not unique", "interaction". The interaction between people in real life, the social state of one person with many faces, is obviously more consistent with quantum theory. Teaching the quantum theory way of thinking to children will allow them to quickly integrate into the forefront of world development. Countries around the world are gradually front-loading quantum teaching. In the United States, quantum computing education has been written into the National K12 Education Act, and in Europe, activities such as quantum computing basic education and quantum science summer camps are prevalent. Students experimenting on the CIQTEK Diamond Quantum Computer for Education CIQTEK Vice President Feng Zedong introduced, CIQTEK Diamond Quantum Computer for Education includes a series of courses on the basic theory of quantum computing, development history and experimental exploration, etc. The experimental part contains continuous wave experiments, Rabi oscillation experiments, echo experiments, T2 experiments, DJ experiments, etc. Students will experience the differences between quantum computing and ordinary computing, and explore the applications of quantum computing in new drug research, big data algorithms, password cracking and other fields. CIQTEK Diamond Quantum Computer for Education The Diamond Quantum Computer for Education is a teaching instrument based on the principle of NV-center and spin magnetic resonance in diamond, which can quantum manipulate and read out the spins of NV-center by controlling physical quantities such as laser, microwave, and magnetic field, so as to achieve quantum computing function.Based on this instrument, CIQTEK can provide overall solutions for quantum computing ...
View MoreLi-Ion Batteries (LIBs) are widely used in electronic devices, electric vehicles, power grid storage, and other fields due to their small size, lightweight, high battery capacity, long cycle life, and high safety.Electron paramagnetic resonance (EPR or ESR) technology can non-invasively probe the inside of the battery and monitor the evolution of electronic properties during the charging and discharging of electrode materials in real-time, thus studying the electrode reaction process close to the real state. It's gradually playing an irreplaceable role in the study of the battery reaction mechanism. Composition and Working Principle of Lithium-ion Battery A lithium-ion battery consists of four main components: the positive electrode, the negative electrode, the electrolyte, and the diaphragm. It mainly relies on the movement of lithium ions between the positive and negative electrodes (embedding and de-embedding) to work. Fig. 1 Lithium-ion Battery Working Principle In the process of battery charging and discharging, the changes of charging and discharging curves on the positive and negative materials are generally accompanied by various microstructural changes, and the decay or even failure of performance after a long time cycle is often closely related to the microstructural changes. Therefore, the study of the constitutive (structure-performance) relationship and electrochemical reaction mechanism is the key to improving the performance of lithium-ion batteries and is also the core of electrochemical research. EPR (ESR) Technology in Lithium-ion Batteries There are various characterization methods to study the relationship between structure and performance, among which, the electron spin resonance (ESR) technique has received more and more attention in recent years because of its high sensitivity, non-destructive, and in situ monitorability. In lithium-ion batteries, using the ESR technique, transition metals such as Co, Ni, Mn, Fe, and V in electrode materials can be studied, and it can also be applied to study the electrons in the off-domain state. The evolution of electronic properties (e.g., change of metal valence) during the charging and discharging of electrode materials will cause changes in EPR (ESR) signals. The study of electrochemically induced redox mechanisms can be achieved by real-time monitoring of electrode materials, which can contribute to the improvement of battery performance. EPR (ESR) Technology in Inorganic Electrode Materials In lithium-ion batteries, the most commonly used cathode materials are usually some electrodeless electrode materials, including LiCoO2, Li2MnO3, etc. The improvement of cathode material performance is the key to improving the overall battery performance. In Li-rich cathodes, reversible O redox can generate additional capacity and thus increase the specific energy of oxide cathode materials. Hence, the s...
View MorePowders are today's raw materials for the preparation of materials and devices in various fields and are widely used in lithium-ion batteries, catalysis, electronic components, pharmaceuticals, and other applications. The composition and microstructure of the raw material powders determine the properties of the material. The particle size distribution ratio, shape, porosity, and specific surface of the raw material powders can match the unique properties of the material. Therefore, the regulation of the microstructure of the raw material powder is a prerequisite for obtaining excellent performance materials. The use of scanning electron microscopy allows observation of the specific surface morphology of the powder and precise analysis of the particle size to optimize the preparation process of the powder. Application of scanning electron microscopy in MOFs materials In the field of catalysis, the construction of metal-organic backbone materials (MOFs) to substantially improve the surface catalytic performance has become one of the hot research topics today. MOFs have the unique advantages of high metal loading, porous structure and catalytic sites, and have great potential as cluster catalysts. Using the CIQTEK Tungsten Filament Scanning Electron Microscope, it can be observed that the MOFs material shows regular cubic shape and the presence of fine particles adsorbed on the surface (Figure 1). The electron microscope possesses a resolution of up to 3 nm and excellent imaging quality, and uniform high-brightness SEM maps can be obtained in different fields of view, which can clearly observe the folds, pores, and particle loading on the surface of MOFs materials. Figure 1 MOFs material / 15 kV/ETD Scanning electron microscopy in silver powder materials In the manufacture of electronic components, electronic paste, as a basic material for manufacturing electronic components, has certain rheological and thixotropic properties, and is a basic functional material integrating materials, chemical and electronic technologies, and the preparation of silver powder is the key to manufacturing silver conductive paste. Using the SEM5000 field emission scanning electron microscope independently developed by CIQTEK, relying on the high voltage tunneling technology, the space charge effect is drastically reduced, and irregular silver powder clustering with each other can be observed (Figure 2). And the SEM5000 has high resolution, so that details can still be seen even at 100,000x magnification. Figure 2 Silver powder/5 kV/Inlens Scanning electron microscopy in lithium iron phosphate Lithium-ion batteries are rapidly occupying the mainstream market because of their high specific energy, long cycle life, no memory effect, and high safety. The use of electron microscopy to observe the positive and negative electrode morphology of lithium-ion batteries is important to improve t...
View MoreWhat is nano alumina? Nano-alumina is widely used in various fields such as ceramic materials, composite materials, aerospace, environmental protection, catalysts, and their carriers because of its high strength, hardness, wear resistance, heat resistance, and large specific surface area [1]. This has led to the continuous improvement of its development technology. Currently, scientists have prepared alumina nanomaterials in various morphologies from one-dimensional to three-dimensional, including spherical, hexagonal sheet, cubic, rod, fibrous, mesh, flower, curly, and many other morphologies [2]. Scanning electron microscopy of alumina nano-particles There are many methods for the preparation of nano alumina, which can be divided into three main categories according to the different reaction methods: Solid-phase, gas-phase, and liquid-phase methods [3]. In order to verify that the results of the prepared alumina nanopowders are as expected, it is necessary to characterize the structure of alumina under each process, and the most intuitive of the many characterization methods is the microscopic observation method. The scanning electron microscope, as a conventional microscopic characterization equipment, has the advantages of large magnification, high resolution, large depth of field, clear imaging, and strong stereoscopic sense, which is the preferred equipment for characterizing the structure of nano-alumina. The following figure shows the alumina powder prepared under different processes observed using CIQTEK Field Emission Scanning Electron Microscope SEM5000, which contains alumina nanopowders in the form of cubes, flakes, and rods, and with particle sizes of tens to hundreds of nanometers. CIQTEK Field Emission Scanning Electron Microscope SEM5000 SEM5000 is a high-resolution, feature-rich field emission scanning electron microscope, with advanced barrel design, in-barrel deceleration, and low aberration non-leakage magnetic objective design, to achieve low-voltage high-resolution imaging, that can be applied to magnetic samples. SEM5000 has optical navigation, perfect automatic functions, well-designed human-machine interaction, and optimized operation, and use process. Regardless of whether the operator has extensive experience, he/she can quickly get started with the task of high-resolution photography. Electron gun type: high-brightness Schottky-field emission electron gun Resolution: 1 nm @ 15 kV 1.5 nm @ 1 kV Magnification: 1 ~ 2500000 x Acceleration voltage: 20 V ~ 30 kV Sample table: five-axis automatic sample table References. [1] Wu ZF. Study on the relationship between the morphology and properties of alumina nanoparticles[J]. Journal of Artificial Crystals, 2020,49(02):353-357. doi:10.16553/j.cnki.issn1000-985x.2020.02.024. [2] Nie Duofa. A brief discussion on the preparation of nanoalumina...
View MoreThe detection and modulation of single quantum states and molecular scale imaging technology are important directions in the development of precision spectroscopy instruments. With the in-depth exploration of magnetic detection technology, CIQTEK independently produced and developed a quantum diamond single spin spectroscopy, based on the spectroscopic technology of nitrogen-vacancy system in doped diamond, which has super high magnetic detection instinct and has wide and important application prospects in different disciplines such as physics, chemistry, biology, materials, and medicine [1-11]. Development of Magnetometry Technology Figure 1: Comparison of the Indicators of Various Magnetometry Techniques Spin magnetic resonance technology is by far one of the most developed and widely used conventional techniques. Magnetic detection-related spectrometers have a long history of development, and there are different methods to achieve magnetic resonance detection which have their own advantages and disadvantages. Figure 1 visualizes the distribution of several general technical means such as Hall sensors, SQUID detectors, and the spin magnetic resonance in terms of sensitivity and resolution [12]. Compared with the conventional magnetometry techniques, the diamond-based magnetic resonance method has a large improvement in both core metrics, which provides a strong reference for the development of a quantum diamond single-spin spectroscopy. Hall sensors have been commonly used in laboratory magnetic field measurements since the 1950s. These detectors are based on the Hall effect for direct measurements of external magnetic fields [13]. When the direction of the magnetic field is different from the direction of the current in the loop, the electrons in the conductor are deflected due to the Lorentz force, and a potential difference is generated, through which the magnitude of the magnetic field is directly measured. Magnetic field probes have mainly consisted of semiconductor crystals that are able to be made into monolithic integrated circuits, which are shock resistant and easy to use but are not accurate enough. Superconducting quantum interferometer (SQUID) is a magnetic flux sensor based on Josephson junctions [14], which can measure weak magnetic signals using the variation of the voltage across the Josephson junction with the external magnetic flux in the closed loop.In the 1960s, Robert et al. successfully developed SQUID.Such magnetometry techniques have high magnetic detection sensitivity, but the instrument needs to operate in a low-temperature environment and expensive. Microscopic magnetic detection based on the diamond system is the emerging method for magnetic resonance detection. The technique combines the optical detection magnetic resonance technique (ODMR) and the point defects of nitrogen-vacancy (NV) centers in diamond, which works by preparing NV centers as quantum interferome...
View MoreIn general, the better a person's memory, the more information they can integrate and process. In quantum computing, the longer a quantum bit can "remember" a quantum state, the more calculations it can perform. The "memory" of quantum computing can be likened to coherence time. What is Coherence Time? Coherence Times is an important indicator of the quality of a quantum bit, it represents the length of time that a quantum bit can remain in a superposition state, the longer the coherence time, the more calculations a quantum computer can perform. Simply put, coherence time is also the "working time" that a quantum computer can use for computation. Currently, ion trap quantum computing has a clear advantage in realizing long coherence. What is the Difficulty of Long Coherence? Quantum bits in most quantum computing routes are highly susceptible to interference from the surrounding environment (Temperature, Noise, and even Cosmic Rays), and trying to maintain their superposition and entanglement for long periods of time is as challenging as trying to keep a group of active kittens in line. Creating the ideal quantum bit is also challenging because there are physical limitations, such as the nature of the materials and the manufacturing process that can lead to imperfect quantum bits. This is like the presence of an active cat, or even a dog, in the middle of a group of well-behaved cats, which can greatly affect the coherence time. T1 and T2, Key Technological Metrics in Quantum Computing When exploring coherence time in quantum computing, we often focus on two parameters: the T1 Time and T2 Time (T1 Time and T2 Time). They are different ways of looking at how long a quantum bit works. T1 Time determines how long you can distinguish between state 1 and state 0 of a quantum bit. When a quantum bit is excited to a high energy level (excited state), similar to a classical bit going from 0 to 1. In a classical bit, the 1 state can be maintained relatively easily, but in a quantum bit it will return to a lower energy state in a certain amount of time. This time is the energy relaxation time. During the T1 time, a quantum bit returns from a high energy state to a lower energy state, i.e., it changes from 1 back to 0. This means that the quantum bit loses the information it carries. The T2 time, on the other hand, represents the time to be able to maintain the phase information in the superposition state; if the T2 time is short, the bit superposition state may evolve into another superposition state or even cease to be a superposition state, thus losing the carried information. In short, both T1 time and T2 time are temporal parameters on the performance of a quantum bit, and they describe how long a quantum bit remains stable in terms of energy level and phase respectively. For quantum computation, longer T1 and T2 times are the goals pursued by quantum computation because it means th...
View MoreSignificance of cardiac magnetic signal detection The human body's magnetic field can reflect information about various tissues and organs within the human body. Measurement of the human body's magnetic field can be used to obtain information about human diseases, and its detection effect and convenience have exceeded the measurement of the human body's bioelectricity. The size of the heart's magnetic field is on the order of a few tens of pT, which is one of the earliest magnetic fields studied by human beings, compared to the brain's. The atrial and ventricular muscles of the heart are the most important parts of the body. Magnetocardiography (MCG) is the result of the complex alternating bioelectric currents that accompany the cyclic contraction and diastole of the atrial and ventricular muscles of the heart. Compared to Electrocardiogram (ECG), cardiac magnetic field detection is not affected by the chest wall and other tissues, and MCG can detect the cardiac magnetic field through a multi-angle, multi-dimensional sensor array, thus providing more information about the heart and enabling precise localization of cardiac heart foci. Compared to CT, MRI and other cardiac research techniques, magnetocardiography is completely radiation-free. Currently, the technology of Magnetocardiography is becoming increasingly mature, with more than 100,000 clinical applications, which are mainly reflected in the following aspects: 01 Coronary heart disease Coronary heart disease is a common and frequent disease, according to statistics, at present, China's coronary heart disease patients have more than 11 million people. Coronary heart disease is the most common cause of death, and the number of deaths even exceeds the total number of deaths from all tumors. For coronary heart disease, MCG mainly detects myocardial repolarization inconsistency caused by myocardial ischemia. For example, Li et al. measured MCG in 101 patients with coronary artery disease and 116 healthy volunteers. The results showed that the three parameters of R-max/ T-max, R-value, and mean angle were significantly higher in patients with coronary artery disease than in normal people. Among 101 patients with coronary artery disease, the proportions of myocardial ischemia detected by MCG, electrocardiography, and echocardiography were 74.26%, 48.51%, and 45.54%, respectively, which showed that the diagnostic accuracy of MCG in patients with coronary artery disease was significantly higher than that of electrocardiography and echocardiography. This shows that the diagnostic accuracy of MCG in patients with coronary heart disease is significantly higher than that of ECG and echocardiography. Reference:Int. J. Clin. Exp. Med. 8(2):2441-2446(2015) 02 Arrhythmias Arrhythmia is defined as an abnormality of the cardiac impulse at the site of origin, the frequency and rhythm of the heartbeat, and any part of the impulse conduction. According to statistics, the number of arrhythmia pat...
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