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基于RFID的医疗设备远程管理系统设计 被引量:2
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作者 向明华 赵菊云 +1 位作者 向国华 吴玲 《自动化技术与应用》 2024年第3期62-65,135,共5页
为提高医院内设备定位精度,设计基于RFID的医疗设备远程管理系统。通过阅读器、电子标签和处理器组成RFID节点,引入AS3992芯片作为核心芯片,实现数据处理和编码,执行远程指令。采用自由空间传播模型计算路径损耗产生值,通过三角定位数... 为提高医院内设备定位精度,设计基于RFID的医疗设备远程管理系统。通过阅读器、电子标签和处理器组成RFID节点,引入AS3992芯片作为核心芯片,实现数据处理和编码,执行远程指令。采用自由空间传播模型计算路径损耗产生值,通过三角定位数学方法计算待定标签位置,采用RFID定位方法确定标签的最近邻居,实现医疗设备的远程定位。实验结果表明,在没有障碍物的情况下,所提系统设备定位误差少于1 m,在有障碍物的情况下,定位误差在2 m左右,证明所提出系统定位准确性较高,满足系统的设计需求。 展开更多
关键词 RFId 医疗设备远程管理 路径损耗 a/d转换
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Applications of carbonic acid solution for developing conversion coatings on Mg alloy 被引量:6
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作者 余秉隆 林俊凱 汪俊延 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第7期1331-1339,共9页
Works on exploring an environmentally clean method for producing an Mg,Al-hydrotalcite(Mg6Al2(OH) 16CO3·4H2O) layer and/or calcium carbonate(CaCO3) layer on Mg alloy in a carbonic acid solution system(aqueous HCO... Works on exploring an environmentally clean method for producing an Mg,Al-hydrotalcite(Mg6Al2(OH) 16CO3·4H2O) layer and/or calcium carbonate(CaCO3) layer on Mg alloy in a carbonic acid solution system(aqueous HCO3-/CO3 2-or Ca 2+ /HCO3-) at 50℃ were reviewed.Conversion treatment for the Mg,Al-hydrotalcite conversion coating was as follows.Mg alloy was treated first in acidic HCO3-/CO3 2-aqueous for precursor layer formation on Mg alloy surface and then in alkaline HCO3-/CO3 2-aqueous to form a crystallized Mg,Al-hydrotalcite coating.Duration of an Mg,Al-hydrotalcite coating on Mg alloy surface was reduced from 12 h to 4 h by the conversion treatment.On the other hand,for reducing the formation time of CaCO3 coating on Mg alloy,the aqueous Ca 2+ /HCO3-with a saturated Ca 2+ content was employed for developing a CaCO3 coating on Mg alloy.A dense CaCO3 coating could yield on Mg alloy surface in 2 h.Corrosion rate(corrosion current density,Jcorr) of the Mg,Al-hydrotalcite-coated sample and CaCO3-coated AZ91D sample was 7-10μA/cm 2,roughly two orders less than the Jcorr of the as-diecast sample(about 200μA/cm 2) . No corrosion spot on the Mg,Al-hydrotalcite-coated sample and CaCO3-coated sample was observed after 72 h and 192 h salt spray test,respectively. 展开更多
关键词 Mg alloy AZ91d alloy CORROSION conversion coating carbonic acid
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A transceiver frequency conversion module based on 3D micropackaging technology 被引量:4
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作者 LIU Boyuan WANG Qingping +1 位作者 WU Weiwei YUAN Naichang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第5期899-907,共9页
The idea of Ku-band transceiver frequency conversion module design based on 3D micropackaging technology is proposed. By using the double frequency conversion technology,the dual transceiver circuit from Ku-band to L-... The idea of Ku-band transceiver frequency conversion module design based on 3D micropackaging technology is proposed. By using the double frequency conversion technology,the dual transceiver circuit from Ku-band to L-band is realized by combining with the local oscillator and the power control circuit to complete functions such as amplification, filtering and gain. In order to achieve the performance optimization and a high level of integration of the Ku-band monolithic microwave integrated circuits(MMIC) operating chip, the 3 D vertical interconnection micro-assembly technology is used. By stacking solder balls on the printed circuit board(PCB), the technology decreases the volume of the original transceiver to a miniaturized module. The module has a good electromagnetic compatibility through special structure designs. This module has the characteristics of miniaturization, low power consumption and high density, which is suitable for popularization in practical application. 展开更多
关键词 KU-BANd frequency conversion 3d packaging CHIP electromagnetic compatibility
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Transcription factor-based gene therapy to treat glioblastoma through direct neuronal conversion 被引量:3
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作者 Xin Wang Zifei Pei +2 位作者 Aasma Hossain Yuting Bai Gong Chen 《Cancer Biology & Medicine》 SCIE CAS CSCD 2021年第3期860-874,共15页
Objective:Glioblastoma(GBM)is the most prevalent and aggressive adult primary cancer in the central nervous system.Therapeutic approaches for GBM treatment are under intense investigation,including the use of emerging... Objective:Glioblastoma(GBM)is the most prevalent and aggressive adult primary cancer in the central nervous system.Therapeutic approaches for GBM treatment are under intense investigation,including the use of emerging immunotherapies.Here,we propose an alternative approach to treat GBM through reprogramming proliferative GBM cells into non-proliferative neurons.Methods:Retroviruses were used to target highly proliferative human GBM cells through overexpression of neural transcription factors.Immunostaining,electrophysiological recording,and bulk RNA-seq were performed to investigate the mechanisms underlying the neuronal conversion of human GBM cells.An in vivo intracranial xenograft mouse model was used to examine the neuronal conversion of human GBM cells.Results:We report efficient neuronal conversion from human GBM cells by overexpressing single neural transcription factor Neurogenic differentiation 1(Neuro D1),Neurogenin-2(Neurog2),or Achaete-scute homolog 1(Ascl1).Subtype characterization showed that the majority of Neurog2-and Neuro D1-converted neurons were glutamatergic,while Ascl1 favored GABAergic neuron generation.The GBM cell-converted neurons not only showed pan-neuronal markers but also exhibited neuron-specific electrophysiological activities.Transcriptome analyses revealed that neuronal genes were activated in glioma cells after overexpression of neural transcription factors,and different signaling pathways were activated by different neural transcription factors.Importantly,the neuronal conversion of GBM cells was accompanied by significant inhibition of GBM cell proliferation in both in vitro and in vivo models.Conclusions:These results suggest that GBM cells can be reprogrammed into different subtypes of neurons,leading to a potential alternative approach to treat brain tumors using in vivo cell conversion technology. 展开更多
关键词 GLIOBLASTOMA neuronal conversion transcription factors Neuro d1 neurogenin-2 Ascl1
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Construction of 2D Zn‐MOF/BiVO_(4)S‐scheme heterojunction for efficient photocatalytic CO_(2) conversion under visible light irradiation 被引量:6
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作者 Zhenlong Zhao Ji Bian +6 位作者 Lina Zhao Hongjun Wu Shuai Xu Lei Sun Zhijun Li Ziqing Zhang Liqiang Jing 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第5期1331-1340,共10页
The construction of S‐scheme heterojunction photocatalysts has been regarded as an effective avenue to facilitate the conversion of solar energy to fuel.However,there are still considerable challenges with regard to ... The construction of S‐scheme heterojunction photocatalysts has been regarded as an effective avenue to facilitate the conversion of solar energy to fuel.However,there are still considerable challenges with regard to efficient charge transfer,the abundance of catalytic sites,and extended light absorption.Herein,an S‐scheme heterojunction of 2D/2D zinc porphyrin‐based metal‐organic frameworks/BiVO_(4)nanosheets(Zn‐MOF/BVON)was fabricated for efficient photocatalytic CO_(2)conversion.The optimal one shows a 22‐fold photoactivity enhancement when compared to the previously reported BiVO4 nanoflake(ca.15 nm),and even exhibits~2‐time improvement than the traditional g‐C3N4/BiVO4 heterojunction.The excellent photoactivities are ascribed to the strengthened S‐scheme charge transfer and separation,promoted CO_(2)activation by the well‐dispersed metal nodes Zn_(2)(COO)_(4)in the Zn‐MOF,and extended visible light response range based on the results of the electrochemical reduction,electron paramagnetic resonance,and in‐situ diffuse reflectance infrared Fourier transform spectroscopy.The dimension‐matched Zn‐MOF/BVON S‐scheme heterojunction endowed with highly efficient charge separation and abundant catalytic active sites contributed to the superior CO2 conversion.This study offers a facile strategy for constructing S‐scheme heterojunctions involving porphyrin‐based MOFs for solar fuel production. 展开更多
关键词 BiVO4 nanosheet 2d zinc porphyrin‐based MOFs modification S‐scheme heterojunction Visible light catalysis CO_(2) conversion
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Design of a 20-Gsps 12-bit time-interleaved analog-to-digital conversion system 被引量:2
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作者 Ruo-Shi Dong Lei Zhao +4 位作者 Jia-Jun Qin Wen-Tao Zhong Yi-Chun Fan Shu-Bin Liu Qi An 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第3期30-40,共11页
The time-interleaved analog-to-digital conversion(TIADC)technique is an effective method for increasing the sampling rate in a waveform digitization system.In this study,a 20-Gsps TIADC system was designed.A wide-band... The time-interleaved analog-to-digital conversion(TIADC)technique is an effective method for increasing the sampling rate in a waveform digitization system.In this study,a 20-Gsps TIADC system was designed.A wide-bandwidth performance was achieved by optimizing the analog circuits,and a sufficient effective number of bits(ENOB)performance guaranteed using the perfect reconstruction algorithm for mismatch error correction.The proposed system was verified by tests,and the results indicated that a-3 dB bandwidth of 6 GHz and the ENOB performance of 8.7 bits at 1 GHz and 7.6 bits at6 GHz were successfully achieved. 展开更多
关键词 Time-interleaved technique High-speed a/d conversion High bandwidth Mismatch error correction
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A new method to create depth information based on lighting analysis for 2D/3D conversion 被引量:1
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作者 Hyunho Han Gangseong Lee +2 位作者 Jongyong Lee Jinsoo Kim Sanghun Lee 《Journal of Central South University》 SCIE EI CAS 2013年第10期2715-2719,共5页
A new method creating depth information for 2D/3D conversion was proposed. The distance between objects is determined by the distances between objects and light source position which is estimated by the analysis of th... A new method creating depth information for 2D/3D conversion was proposed. The distance between objects is determined by the distances between objects and light source position which is estimated by the analysis of the image. The estimated lighting value is used to normalize the image. A threshold value is determined by some weighted operation between the original image and the normalized image. By applying the threshold value to the original image, background area is removed. Depth information of interested area is calculated from the lighting changes. The final 3D images converted with the proposed method are used to verify its effectiveness. 展开更多
关键词 LIGHTING ANALYSIS depth INFORMATION focus/defocus INFORMATION 2d/3d conversion
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A Universal Atomic Substitution Conversion Strategy Towards Synthesis of Large‑Size Ultrathin Nonlayered Two‑Dimensional Materials 被引量:2
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作者 Mei Zhao Sijie Yang +10 位作者 Kenan Zhang Lijie Zhang Ping Chen Sanjun Yang Yang Zhao Xiang Ding Xiaotao Zu Yuan Li Yinghe Zhao Liang Qiao Tianyou Zhai 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第11期79-91,共13页
Nonlayered two-dimensional(2D)materials have attracted increasing attention,due to novel physical properties,unique surface structure,and high compatibility with microfabrication technique.However,owing to the inheren... Nonlayered two-dimensional(2D)materials have attracted increasing attention,due to novel physical properties,unique surface structure,and high compatibility with microfabrication technique.However,owing to the inherent strong covalent bonds,the direct synthesis of 2D planar structure from nonlayered materials,especially for the realization of large-size ultrathin 2D nonlayered materials,is still a huge challenge.Here,a general atomic substitution conversion strategy is proposed to synthesize large-size,ultrathin nonlayered 2D materials.Taking nonlayered CdS as a typical example,large-size ultrathin nonlayered CdS single-crystalline flakes are successfully achieved via a facile low-temperature chemical sulfurization method,where pre-grown layered CdI2 flakes are employed as the precursor via a simple hot plate assisted vertical vapor deposition method.The size and thickness of CdS flakes can be controlled by the CdI2 precursor.The growth mechanism is ascribed to the chemical substitution reaction from I to S atoms between CdI2 and CdS,which has been evidenced by experiments and theoretical calculations.The atomic substitution conversion strategy demonstrates that the existing 2D layered materials can serve as the precursor for difficult-to-synthesize nonlayered 2D materials,providing a bridge between layered and nonlayered materials,meanwhile realizing the fabrication of large-size ultrathin nonlayered 2D materials. 展开更多
关键词 Nonlayered 2d materials Large-size ultrathin CdS flakes Atomic substitution conversion Layered-nonlayered structural transformation
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A Distributed 2D-to-3D Video Conversion System 被引量:1
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作者 张哲斌 张吉安 +2 位作者 张学西 王亦洲 高文 《China Communications》 SCIE CSCD 2013年第5期30-38,共9页
2D-to-3D video conversion is a feasible way to generate 3D programs for the current 3DTV industry. However, for large-scale 3D video production, current systems are no longer adequate in terms of the time and labor re... 2D-to-3D video conversion is a feasible way to generate 3D programs for the current 3DTV industry. However, for large-scale 3D video production, current systems are no longer adequate in terms of the time and labor required for conversion. In this paper, we introduce a distributed 2D-to-3D video conversion system that includes a 2D-to-3D video conversion module, architecture of the parallel computation on the cloud, and 3D video coding in the system. The system enables cooperation among multiple users in the simultaneous completion of their conversion tasks so that the conversion efficiency is greatly promoted. In the experiments, we evaluate the system based on criteria related to both time consumption and video coding performance. 展开更多
关键词 3d video 2d-to-3d conversion distributed system
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“6D法则”在住院医师规范化培训院级师资培训中的探索和运用——以教学查房培训为例
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作者 何怀伟 师芸 +2 位作者 黄亚玲 柳琪林 韩一哲 《中国毕业后医学教育》 2024年第5期352-355,共4页
目的在住院医师规范化培训(简称住培)院级师资培训中引入“6 D法则”,推进师资培训的“三个转化”,即住培师资岗位需求的转化、培训内容的转化、师资内在的素质和能力的转化。方法以院级教学查房培训为例,将培训设计为准备、培训、转化... 目的在住院医师规范化培训(简称住培)院级师资培训中引入“6 D法则”,推进师资培训的“三个转化”,即住培师资岗位需求的转化、培训内容的转化、师资内在的素质和能力的转化。方法以院级教学查房培训为例,将培训设计为准备、培训、转化和评估4个阶段,实现培训后的转化以及培训质量的改善。结果基于“6 D法则”的教学查房培训过后,以教学督导的形式进行总结性评估。接受过教学查房培训的师资平均得分为90.00分,未接受过教学查房培训的师资平均得分为84.93分,培训达到了预期目标。结论“6 D法则”采用系统化思维方式,注重学习转化和绩效的改善,将以终为始的理念贯穿整个培训过程,有利于培训取得实效。 展开更多
关键词 师资培训 6 d法则 培训转化 教学查房
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Organic-magnesium complex conversion coating on AZ91D magnesium alloy
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作者 陈晓明 李光玉 连建设 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第B07期643-647,共5页
An organic-magnesium complex conversion(OMCC)coating on AZ91D magnesium alloy was obtained by treating in a solution containing organic compounds.SEM,FESEM and XPS were used to examine the surface morphology,thickness... An organic-magnesium complex conversion(OMCC)coating on AZ91D magnesium alloy was obtained by treating in a solution containing organic compounds.SEM,FESEM and XPS were used to examine the surface morphology,thickness and structure of the conversion coatings.The results show that the continuous and uniform conversion coating is deposited on AZ91D alloy and the main component of the coatings is organic compound containing benzene ring,which forms a chemical bond with magnesium.The polarization measurement and salt spray test show that the corrosion resistance of the conversion coating is much higher than that of traditional chromate conversion coating. 展开更多
关键词 chromium-free conversion coating organic compound CORROSION XPS AZ91d magnesium alloy
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Precise conversion between virtual world and real world in stereoscopic imaging
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作者 姚晓永 吴平东 黄漫玲 《Journal of Beijing Institute of Technology》 EI CAS 2013年第2期191-196,共6页
A method for precise conversion between virtual world and real world is put forward in this paper. The method aims to precisely establish the connection between the virtual coordinates and the real coordinates with Op... A method for precise conversion between virtual world and real world is put forward in this paper. The method aims to precisely establish the connection between the virtual coordinates and the real coordinates with OpenGL. In the virtual world, two virtual cameras are set to capture the left and right perspective planar images, and coordinates of the planar images can be calculated by the perspective projection model. With coordinates of planar images, coordinates of the stereo- scopic image synthesized in the real world can be calculated by the binocular observation model. Therefore, the corresponding connection between the two systems is established. Experimental re- suits match data from this method well. Therefore, this method can precisely realize the conversion and the interactivity, laying a solid foundation for further study. 展开更多
关键词 virtual world spatial coordinates OpenGL model 2d-to-3d conversion
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Method to Increase Micro-controller A/D Conversion Speed
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作者 唐鹤权 《Journal of Donghua University(English Edition)》 EI CAS 2004年第5期128-131,共4页
The speed and cost of A/D conversion are conflict to each other. As micro-controller speed is increasing and its internal function is improving, full utilization of its internal resource can dramatically increase A/D ... The speed and cost of A/D conversion are conflict to each other. As micro-controller speed is increasing and its internal function is improving, full utilization of its internal resource can dramatically increase A/D conversion speed and without compromising conversion quality. MSP430F11x1 series micro-controller is exploited to increase A/D conversion speed. 展开更多
关键词 Micro-controller a/d conversion Speed and cost.
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Optical Analog-to-digital Conversion Scheme Based on Tunable Fabry-Perot Resonator
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作者 LI Zheng 《Semiconductor Photonics and Technology》 CAS 2007年第4期298-304,共7页
Proposed is an interference type of optical analog-to-digital conversion(ADC). The refractive index of Fabry-Perot cavity changes with different voltages. The Fabry-Perot resonator converts electronic intensity into l... Proposed is an interference type of optical analog-to-digital conversion(ADC). The refractive index of Fabry-Perot cavity changes with different voltages. The Fabry-Perot resonator converts electronic intensity into light wavelength through selecting lights of different wavelengthes. The parameters of the scheme are acquired with the transmission matrix of optical element and the time of steady-state light field. The maximum sampling speedes of 4-bit, 6-bit, 7-bit, 8-bit and 9-bit(ADC) are 1.695×1010 count/s, 4.33×109 count/s, 2.38×109 count/s, 1.24×109 count/s and 5.9×108 count/s, respectively. 展开更多
关键词 optical a/d conversion photonic sampling wavelength-division multiplexing Pockels effect
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Conversion of U-238 and Th-232 Using a Fusion Neutron Source
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作者 Xianjun Zheng Baiquan Deng +1 位作者 Wei Ou Fujun Gou 《World Journal of Nuclear Science and Technology》 2014年第4期222-227,共6页
This article proposes a general framework for the conversion of U-238 and Th-232 utilizing fusion-produced neutrons. This recognizes that emerging fusion technologies may not produce sufficient net energy output to ju... This article proposes a general framework for the conversion of U-238 and Th-232 utilizing fusion-produced neutrons. This recognizes that emerging fusion technologies may not produce sufficient net energy output to justify stand-alone applications, yet may be commercially viable for breeder transmutation or hybrid fusion-fission reactor concepts proposed herein to dispose of nuclear wastes and long life high radioactive fission products remaining in shutdown nuclear power plants. Results show that this could be achievable within a decade, given an appropriate fusion source. However, if 20% beryllium of nuclei density is added to the convertor blanket, the efficiency of the conversion process can be significantly increased. Also, the neutron energy spectrum resulting from dense D-D plasma core fusion is much softer than D-T fusion neutron source, hence the probability of (n, p) (n, α) backward decay reaction paths will be smaller and the conversion efficiency will be elevated. 展开更多
关键词 conversion BREEdER d-d FUSION
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应用Converse3D设计和实现虚拟校园 被引量:5
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作者 陶健林 王广军 +1 位作者 章健 苏本跃 《安庆师范学院学报(自然科学版)》 2013年第1期62-65,共4页
高等院校合理运用虚拟校园系统,不仅立体展示校园实景信息和校园文化,而且可以更有效地进行学校的组织管理,同时能够提高学校的知名度、增强学校的竞争力。本文以安庆职业技术学院校园为基础,建立三维实景模型,利用Converse3D虚拟漫游平... 高等院校合理运用虚拟校园系统,不仅立体展示校园实景信息和校园文化,而且可以更有效地进行学校的组织管理,同时能够提高学校的知名度、增强学校的竞争力。本文以安庆职业技术学院校园为基础,建立三维实景模型,利用Converse3D虚拟漫游平台,建立虚拟校园系统,实现实时交互式漫游。 展开更多
关键词 虚拟校园 漫游 三维实景模型 converse3d 实时交互式
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Activation of 2D MoS_(2) electrodes induced by high-rate lithiation processes 被引量:1
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作者 Tianzhu Liu Georgian Melinte +2 位作者 Oleksandr Dolotko Michael Knapp Beatriz Mendoza-Sánchez 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第3期56-70,I0003,共16页
MoS_(2) is a highly promising material for application in lithium-ion battery anodes due to its high theoretical capacity and low cost.However,problems with a fast capacity decay over cycling,especially at the first c... MoS_(2) is a highly promising material for application in lithium-ion battery anodes due to its high theoretical capacity and low cost.However,problems with a fast capacity decay over cycling,especially at the first cycles,and poor rate performance have deterred its practical implementation.Herein,electrodes comprised solely of few-layers 2D MoS_(2) nanosheets have been manufactured by scalable liquid-phase exfoliation and spray deposition methods.The long-standing controversy questioning the reversibility of conversion processes of MoS_(2)-based electrodes was addressed.Raman studies revealed that,in 2D MoS_(2) electrodes,conversion processes are indeed reversible,where nanostructure played a key role.Cycling of the electrodes at high current rates revealed an intriguing phenomenon consisting of a continuously increasing capacity after ca.100-200 cycles.This phenomenon was comprehensively addressed by a variety of electrochemical and microscopy methods that revealed underlying physical activation mechanisms that involved a range of profound electrode structural changes.Activation mechanisms delivered a capacitive electrode of a superior rate performance and cycling stability,as compared to the corresponding pristine electrodes,and to MoS_(2) electrodes previously reported.Herein,we have devised a methodology to overcome the problem of cycling stability of 2D MoS_(2) electrodes.Moreover,activation of electrodes constitutes a methodology that could be applied to enhance the energy storage performance of electrodes based on other 2D nanomaterials,or combinations thereof,strategically combining chemistries to engineer electrodes of superior energy storage properties. 展开更多
关键词 2d MoS_(2) Liquid-phase exfoliation Spray-deposition conversion processes Activation mechanisms Energy storage mechanisms
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基于DH方法的反应堆压力容器焊缝检测机器人运动学分析 被引量:1
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作者 关光 李思颖 孙茂荣 《工业控制计算机》 2023年第5期73-74,77,共3页
为保证核电站安全稳定运行,在换料大修期间需要对反应堆压力容器进行检查。基于以上实际工作需求,以反应堆压力容器焊缝检查机器人为基础,进行了运动学分析,利用矢量积法对关节空间到操作空间的速度进行了转化,求取了其雅可比矩阵,并对... 为保证核电站安全稳定运行,在换料大修期间需要对反应堆压力容器进行检查。基于以上实际工作需求,以反应堆压力容器焊缝检查机器人为基础,进行了运动学分析,利用矢量积法对关节空间到操作空间的速度进行了转化,求取了其雅可比矩阵,并对位置和速度误差要求进行了分析,通过仿真以及实际测试,验证了该系统控制算法的有效性。 展开更多
关键词 反应堆压力容器 机器人 d-H算法 速度转化
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Novel carbon-nitride based catalysts for enhanced CH_(4) reforming under visible light: From morphology to heterojunction design principles
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作者 Yufei Huang Ding Wei +5 位作者 Ziyi Li Yu Mao Yangqiang Huang Bo Jin Xiao Luo Zhiwu Liang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期423-432,I0011,共11页
The synthesis of high value-added chemical products using CO_(2)and CH_(4)is a promising CO_(2)conversion technology that can reduce greenhouse gas emissions while also alleviating the energy crisis.However,problems s... The synthesis of high value-added chemical products using CO_(2)and CH_(4)is a promising CO_(2)conversion technology that can reduce greenhouse gas emissions while also alleviating the energy crisis.However,problems such as high energy consumption and strict reaction conditions in reforming process hinder the further development of the technology.In this work,carbon-nitrogen based composites were prepared for the first time according to the design principle from morphology to heterojunction,which is innovatively applied in the process of photocatalytic CH4reforming.Firstly,C_(3)N_(4)materials with different dimensions(D) are prepared and applied to a CO_(2)-CH_(4)photocatalytic system.Additionally,the 2D/2D TiO_(2)/g-C_(3)N_(4)heterostructure is constructed with the ultrasonic impregnation method to further improve charge generation,transfer,and separation efficiency.It is worth noting that the yield of CO reaches173.80 μmol g^(-1),and the catalytic performance is improved by 1546% compared to bulk C_(3)N_(4).Moreover,the physical and chemical properties of 2D/2D TiO_(2)/g-C_(3)N_(4)materials are studied using a variety of cha racterization methods.Furthermore,the work fu nction and adsorption energy of different C3N4/TiO_(2)models for CO_(2)adsorption are calculated by density functional theory(DFT).Then,a possible catalytic mechanism for photocatalytic CO_(2)and CH_(4) conversion is proposed based on DFT calculations and experimental results.This work provides a new technical route for the rapid conversion of CO_(2)and CH_(4) at room temperature,as well as a new research concept for achieving carbon neutrality. 展开更多
关键词 PHOTOCATALYTIC CO_(2) CH_(4) 2d/2dTiO_(2)/g-C_(3)N_(4) conversion
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D-塔格糖的生理活性及生物合成研究进展
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作者 李子杰 沈立群 +2 位作者 费康清 陈洲 中西秀树 《食品科学技术学报》 EI CAS CSCD 北大核心 2023年第6期20-28,共9页
D-塔格糖是一种重要的稀有己酮糖,其甜度是蔗糖的92%,热量只有蔗糖的三分之一;D-塔格糖分别于2001年和2014年被美国食品药品监督管理局和我国卫生和计划生育委员会批准为食品新原料。D-塔格糖具有降低血糖、减少肥胖、改善肠道菌群、抗... D-塔格糖是一种重要的稀有己酮糖,其甜度是蔗糖的92%,热量只有蔗糖的三分之一;D-塔格糖分别于2001年和2014年被美国食品药品监督管理局和我国卫生和计划生育委员会批准为食品新原料。D-塔格糖具有降低血糖、减少肥胖、改善肠道菌群、抗龋齿、抗氧化等功能。D-塔格糖作为一种理想功能性甜味剂,具有广泛的应用价值,然而塔格糖的生产成本以及产量一直是限制塔格糖发展和应用的重要原因。D-塔格糖的合成方法主要有化学合成法和生物转化法。化学合成法生产D-塔格糖虽然是一种经济有效的方法,但是在生产过程中需要高温高压的条件,并且容易生成山梨糖、甘露糖等杂糖,不利于分离纯化。为了克服这些缺点,生物转化法生产D-塔格糖得到了广泛的关注和研究,因此,系统阐述了以不同底物,如己糖(半乳糖醇、D-半乳糖和D-果糖)、乳糖、多糖(麦芽糊精和淀粉)转化成D-塔格糖的研究进展和优缺点,并对其未来研究趋势进行了展望,以期为D-塔格糖的研发与生产提供借鉴。 展开更多
关键词 d-塔格糖 生理功能 L-阿拉伯糖异构酶 乳糖 生物转化法
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