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341.
Jiayi Liu Yanhong Tong Da Xian Xiangtao Chen Chengda Yang Runnan Zou Xiaoqian Liu Zhongzhu Liang Xiaoli Zhao Qingxin Tang Yichun Liu 《Advanced functional materials》2024,34(1):2306704
Easy and convenient reading for blinds is of great significance for lowering their learning, entertainment, and communication barrier, and improving their living quality. The general solution is to learn braille, far from satisfying the meet of the blinds’ daily learning and communication. Here, a new-type conductor/insulator-identifiable e-tattoo proximity sensor is developed by simply depositing the circular interdigitated electrodes on organic semiconductor. The discriminable recognition toward conductors and insulators is realized only based on a single e-tattoo device. The sensors not only enable recognition of the protruding characters like braille based on distance difference, but also enable recognition of the handwriting ink-brush and pencil graphite characters based on the unique advantage of the sensors in distinguishing conduct and insulator. These results open a new route to realize the material category recognition, provide a user-friendly way to help the visual impaired effectively reintegrate into society, and broaden the application field of proximity sensors. 相似文献
342.
生物酶影响着物质代谢和质能转换等生命活动,生物体内某些酶的活性变化会导致疾病的发生。发展新型的酶分析方法对深刻理解生物代谢过程、疾病诊断和药物研发等具有重要意义。毛细管电泳(CE)具有分离效率高、分析速度快、操作简单和样品消耗少以及可与多种检测手段联用等优点,在酶分析研究中越来越受到关注。CE酶分析主要包括离线和在线两种模式,其中,固定化酶微反应器与毛细管电泳联用(CE-IMER)的在线酶分析已经成为主要的酶分析方法之一。CE-IMER充分结合了固定化酶和CE的优势,将游离酶固定在毛细管内,不仅可以显著提高酶的稳定性和重复使用性,而且可以实现纳升规模溶液的自动化酶分析,进而显著降低酶分析成本。目前已有大量方法制备IMER用于CE酶分析,然而如何构建性能良好、可再生使用、酶固载量大、自动化程度高的CE-IMER一直是该领域重点研究的问题。DNA定向固定化技术(DDI)可以充分利用DNA分子的碱基互补配对(A-T, C-G),在温和的生理条件下特异性固定生物大分子。由于短链双螺旋DNA分子具有较强的机械刚性和物理化学稳定性,通过DDI将酶固定在载体表面,有利于降低传质阻力,提高酶与底物的接... 相似文献
343.
分析了SPICE BSIM3模型对高压双扩散漏MOSFET(HV double diffuse drain MOSFET)模拟过程中产牛的较大偏差,有针对性地提出一种由nMOSFET,MESFET,二极管等常规SPICE器件组成的高压晶体管宏模型.该宏模型结构简单、使用方便,能准确描述HVMOS的I-V特性.为了提高该模型的尺寸可缩放性(scalability),将MESFET阈值电压对体电压的敏感因子K1进行优化,提取了不同沟道尺寸(W/L)下K1取值的半经验公式,使该宏模型能够适用于不同尺寸的晶体管,大大提高了它的实用价值.该尺寸可缩放宏模型(scalable macromodel)能应用于基于SPICE模型的各种通用EDA软件. 相似文献
344.
345.
虚拟场景要求有更自然的交互范式以满足用户需求,图形化范式可作为自然范式的有效补充,目前对图形化范式在虚拟空间中的应用研究较少,在应用时,图形化范式与虚拟场景中的主体物可能存在深度冲突。本文提出一种新的交互范式——SOMRM范式,并以虚拟现实(VR)找不同和增强现实(AR)俄罗斯方块场景为例,对添加光圈模糊和调节组件与被试间距离2种缓解虚拟场景中深度冲突的方式进行了研究。通过分析被试在虚拟场景中执行查看、抓取、滑动等交互任务所需的时间和偏差等数据,从易学性、准确性、易用性、真实性、舒适性等6个维度上比较了2种深度冲突缓解方式。研究结果表明,添加光圈模糊能较好缓解虚拟场景交互中的深度冲突。 相似文献
346.
Hongmin Yin Jiayi Ma Zhidong Li Yonghong Li Tong Meng Zhenwu Tang 《Molecules (Basel, Switzerland)》2021,26(8)
Serious pollution of multiple chemicals in irregulated e-waste recycling sites (IR-sites) were extensively investigated. However, little is known about the pollution in regulated sites. This study investigated the occurrence of 21 polybrominated diphenyl ethers (PBDEs) and 10 metals in a regulated site, in Eastern China. The concentrations of PBDEs and Cd, Cu, Pb, Sb, and Zn in soils and sediments were 1–4 and 1–3 orders of magnitude lower than those reported in the IR-sites, respectively. However, these were generally comparable to those in the urban and industrial areas. In general, a moderate pollution of PBDEs and metals was present in the vegetables in this area. A health risk assessment model was used to calculate human exposure to metals in soils. The summed non-carcinogenic risks of metals and PBDEs in the investigated soils were 1.59–3.27 and 0.25–0.51 for children and adults, respectively. Arsenic contributed to 47% of the total risks and As risks in 71.4% of the total soil samples exceeded the acceptable level. These results suggested that the pollution from e-waste recycling could be substantially decreased by the regulated activities, relative to poorly controlled operations, but arsenic pollution from the regulated cycling should be further controlled. 相似文献
347.
348.
Shuyi Yang Wensheng Zhang Guoliang Pan Jiaying Chen Jiayi Deng Ke Chen Xianglun Xie Dongxue Han Mengjiao Dai Li Niu 《Angewandte Chemie (International ed. in English)》2023,62(43):e202312076
The effective conversion of carbon dioxide (CO2) and nitrogen (N2) into urea by photocatalytic reaction under mild conditions is considered to be a more environmentally friendly and promising alternative strategies. However, the weak adsorption and activation ability of inert gas on photocatalysts has become the main challenge that hinder the advancement of this technique. Herein, we have successfully established mesoporous CeO2-x nanorods with adjustable oxygen vacancy concentration by heat treatment in Ar/H2 (90 % : 10 %) atmosphere, enhancing the targeted adsorption and activation of N2 and CO2 by introducing oxygen vacancies. Particularly, CeO2-500 (CeO2 nanorods heated treatment at 500 °C) revealed high photocatalytic activity toward the C−N coupling reaction for urea synthesis with a remarkable urea yield rate of 15.5 μg/h. Besides, both aberration corrected transmission electron microscopy (AC-TEM) and Fourier transform infrared (FT-IR) spectroscopy were used to research the atomic surface structure of CeO2-500 at high resolution and to monitor the key intermediate precursors generated. The reaction mechanism of photocatalytic C−N coupling was studied in detail by combining Density Functional Theory (DFT) with specific experiments. We hope this work provides important inspiration and guiding significance towards highly efficient photocatalytic synthesis of urea. 相似文献
349.
Yaru Yang Qingjun Zhu Jiayi Yang Han Liu Yang Ren Xulei Sui Panpan Wang Gang Sun Zhenbo Wang 《Advanced functional materials》2023,33(46):2304979
Li-rich manganese base oxides (LRNCM) are regarded as one of the most promising cathode materials among next-generation high-energy density Li-ion batteries due to the coupling effect of anion and cation redox. However, serious oxygen release, surface structure corrosion, and transformation seriously damage their electrochemical performance and restrict their commercialization process. Herein, a dual gaseous surface treatment strategy with ammonium bicarbonate is designed to reconstruct the surface chemical and structural characteristics of LRNCM. As a result, an enriched oxygen vacancies mixed-phase surface layer is achieved, which contains spinel phase and cation-disordered phase. The integration of the surface mixed phase effectively inhibits irreversible oxygen loss, prevents electrode corrosion, and promotes fast Li-ion diffusion. Accordingly, the modified cathode exhibits excellent specific capacity, high-rate capability, and superior cycle life at both 25 and 60 °C. Particularly at high temperatures, it achieves impressive performance: initial coulombic efficiency (82.0 vs 74.4%), cycling stability at 1 C after 100 cycles (92.6 vs 83.8%), and rate performance at 5 C (56.0 vs 48.7%). This reconfiguration approach introduces a novel idea for the design of cathode material interfaces. 相似文献
350.
Zheng Li Jiayi Wu Jiawen Yang Kai Li Ji Chen Shuainan Huang Qiang Ji Xiaochao Kong Sumei Xie Wenxuan Zhan Beilei Zhang Ke Ye Qingfan Liu Zhengsheng Mao Yue Cao Huijie Huang Youjia Yu Kang Wang Yanfang Yu Ding Li Feng Chen Peng Chen 《Electrophoresis》2023,44(15-16):1187-1196
DNA-based ancestry inference has long been a research hot spot in forensic science. The differentiation of Han Chinese population, such as the northern-to-southern substructure, would benefit forensic practice. In the present study, we enrolled participants from northern and southern China, each participant was genotyped at ∼400 K single-nucleotide polymorphisms (SNPs) and data of CHB and CHS from 1000 Genomes Project were used to perform genome-wide association analyses. Meanwhile, a new method combining genome-wide association study (GWAS) analyses with k-fold cross-validation in a small sample size was introduced. As a result, one SNP rs17822931 emerged with a p-value of 7.51E − 6. We also simulated a huge dataset to verify whether k-fold cross-validation could reduce the false-negative rate of GWAS. The identified ABCC11 rs17822931 has been reported to have allele frequencies varied with the geographical gradient distribution in humans. We also found a great difference in the allele frequency distributions of rs17822931 among five different cohorts of the Chinese population. In conclusion, our study demonstrated that even small-scale GWAS can also have potential to identify effective loci with implemented k-fold cross-validation method and shed light on the potential maker of rs17822931 in differentiating the north-to-south substructure of the Han Chinese population. 相似文献