期刊文献+
共找到3,345篇文章
< 1 2 168 >
每页显示 20 50 100
Preparation of CeO_(2)/NiO Ammonia Gas Sensor and Its Application in Breath Detection
1
作者 DING Pengfei ZHANG Hongyan +3 位作者 YANG Chen ZHANG Haiyang MA Xiujuan LI Xudong 《新疆大学学报(自然科学版中英文)》 2025年第5期550-560,共11页
A high-performance ammonia(NH3)sensor is prepared based on CeO_(2)/NiO composite,using a hydrothermal method.Experimental findings confirm that the CeO_(2)/NiO composite significantly enhances the performance of the N... A high-performance ammonia(NH3)sensor is prepared based on CeO_(2)/NiO composite,using a hydrothermal method.Experimental findings confirm that the CeO_(2)/NiO composite significantly enhances the performance of the NiO-based NH3 sensor.This improvement is primarily due to the increase in oxygen vacancies(Ov),chemically adsorbed oxygen(Oc),and the proportion of Ni3+on the surface of the CeO_(2)/NiO.The CeO_(2)/NiO sensor shows a high response to NH3,exhibiting response/recovery times of 1.8 s/0.9 s at the NH3 concentration of 5×10^(−6)mL/m^(3),with the theoretical lowest detection limit of 98.651×10^(−9)mL/m^(3).Additionally,the CeO_(2)/NiO sensor has been successfully applied in the simulated detection of Helicobacter pylori infection,highlighting its significant research value and potential application prospects in biomedical diagnostics. 展开更多
关键词 gas sensor nh3 detection CeO_(2)/NiO breath detection
在线阅读 下载PDF
Ti_(3)C_(2)T_(x) Composite Aerogels Enable Pressure Sensors for Dialect Speech Recognition Assisted by Deep Learning
2
作者 Yanan Xiao He Li +8 位作者 Tianyi Gu Xiaoteng Jia Shixiang Sun Yong Liu Bin Wang He Tian Peng Sun Fangmeng Liu Geyu Lu 《Nano-Micro Letters》 2025年第5期1-15,共15页
Wearable pressure sensors capable of adhering comfortably to the skin hold great promise in sound detection.However,current intelligent speech assistants based on pressure sensors can only recognize standard languages... Wearable pressure sensors capable of adhering comfortably to the skin hold great promise in sound detection.However,current intelligent speech assistants based on pressure sensors can only recognize standard languages,which hampers effective communication for non-standard language people.Here,we prepare an ultralight Ti_(3)C_(2)T_(x)MXene/chitosan/polyvinylidene difluoride composite aerogel with a detection range of 6.25 Pa-1200 k Pa,rapid response/recovery time,and low hysteresis(13.69%).The wearable aerogel pressure sensor can detect speech information through the throat muscle vibrations without any interference,allowing for accurate recognition of six dialects(96.2%accuracy)and seven different words(96.6%accuracy)with the assistance of convolutional neural networks.This work represents a significant step forward in silent speech recognition for human–machine interaction and physiological signal monitoring. 展开更多
关键词 Pressure sensor Wearable sensor Ti_(3)C_(2)T_(x) composite aerogel Dialect speech recognition
在线阅读 下载PDF
基于IASI的京津冀及周边NH3分布特征及影响因素分析 被引量:1
3
作者 宋小可 姜磊 +5 位作者 鹿海峰 沈秀娥 王新辉 孙爽 李磊 李金香 《中国环境科学》 北大核心 2025年第1期30-39,共10页
红外大气探测干涉仪(IASI)卫星遥感数据,开展京津冀及周边地区大气氨排放强度和氨总量的核算方法研究,为大气氨的遥感监测应用和氨减排提供支持.首先,对空间非连续数据进行空间插值,进而统计大气氨年均排放强度(YNH_(3))、季均排放强度(... 红外大气探测干涉仪(IASI)卫星遥感数据,开展京津冀及周边地区大气氨排放强度和氨总量的核算方法研究,为大气氨的遥感监测应用和氨减排提供支持.首先,对空间非连续数据进行空间插值,进而统计大气氨年均排放强度(YNH_(3))、季均排放强度(QNH_(3))、月均排放强度(MNH_(3)),并估算大气氨总量(TNH_(3)).然后,据此分析研究区大气氨的空间分布特征及时间变化规律.最后,探究了大气氨排放的影响因素.结果表明:2014~2022年,研究区的大气氨日均排放强度为7.99kg/km^(2),区域中部是YNH_(3)高值区,5个柱浓度低且增长率也低的地级市主要分布在冀北和豫南,8个柱浓度低但增长率高的地级市分布在豫西南、冀中和胶东半岛,19个柱浓度高但增长率低和16个柱浓度高且增长率也高的地级市分布在区域中部和环渤海一带.9年间,YNH_(3)和TNH_(3)均呈增长趋势,研究区的YNH_(3)从5.89kg/km^(2)增长到9.20kg/km^(2),复合年均增长率为5.73%;TNH_(3)从1169kt增长到1825kt;时间分布上,QNH_(3)呈周期性变化特征,夏季是QNH_(3)峰值季,7月是MNH_(3)峰值月.TNH_(3)与耕地和人口的相关性高,且其空间分布高度一致,表明农业和人口是氨排放的重要影响因素,随机森林分析结果表明农业源和生活源是最显著的氨减排因子.本研究证明大气氨遥感监测能为空气质量监测业务提供数据支持. 展开更多
关键词 nh3 IASI 时空特征 影响因素
在线阅读 下载PDF
Cu-MOFs催化剂的合成及NH3-SCR脱硝应用研究 被引量:1
4
作者 陈立志 孙毓霞 +2 位作者 郭鹏 贺超 谢又妍 《安全与环境学报》 北大核心 2025年第4期1584-1592,共9页
为减少燃煤过程中产生的NOx排放,开发了具有高性能选择性催化还原法烟气脱硝(Selective Catalytic Reduction,SCR)催化剂。研究采用水热法合成了Cu-MOFs系列催化剂,以筛选可催化去除NOx的催化剂。结果显示:当底物与配体物质的量比为1∶1... 为减少燃煤过程中产生的NOx排放,开发了具有高性能选择性催化还原法烟气脱硝(Selective Catalytic Reduction,SCR)催化剂。研究采用水热法合成了Cu-MOFs系列催化剂,以筛选可催化去除NOx的催化剂。结果显示:当底物与配体物质的量比为1∶1,反应时间为12 h,温度为120℃时,合成的Cu-MOFs催化剂的得率最高,高达98.71%。在此条件下,催化剂脱硝活性窗口较宽(120~300℃),且随着温度的升高NO去除率从45.11%上升至96.32%。通过系列表征分析脱硝反应机制,发现催化剂表面Cu^(2+)、Cu^(+)共存,且Cu^(2+)参与了NO的去除过程,部分Cu^(2+)转化为了Cu^(+)。 展开更多
关键词 环境工程学 烟气脱硝 nh3-SCR Cu-MOFs 演变规律
原文传递
不同生物炭添加量的生物滤池对堆肥臭气中NH3去除效果的研究
5
作者 郭文袖 王黎明 《现代化农业》 2025年第4期62-65,共4页
近年来,随着我国畜牧养殖业的快速发展,恶臭污染已成为制约和美乡村建设的主要问题。为探索以腐熟堆肥为主,不同生物炭添加量的生物滤池对猪粪堆肥臭气去除的影响,研究以猪粪堆肥为臭气源,进行了为期24d的试验,分析臭气去除过程中填料... 近年来,随着我国畜牧养殖业的快速发展,恶臭污染已成为制约和美乡村建设的主要问题。为探索以腐熟堆肥为主,不同生物炭添加量的生物滤池对猪粪堆肥臭气去除的影响,研究以猪粪堆肥为臭气源,进行了为期24d的试验,分析臭气去除过程中填料温度、含水率等指标变化规律。研究结果表明:生物滤池在处理猪粪堆肥臭气过程中,以腐熟堆肥为主,炭含量为20%的生物滤池对NH3的去除效果最佳。就地就近利用堆肥及生物炭组合作为生物滤池填料去除堆肥臭气具有很好的效果,可以在工厂化堆肥中进行推广应用。 展开更多
关键词 生物炭 腐熟堆肥 恶臭气体 nh3
在线阅读 下载PDF
模型视角下以NH3为核心的三元整合教学
6
作者 钟国华 《中学化学教学参考》 2025年第28期17-22,共6页
开展建模教学有助于学生形成解决陌生问题的认识角度和思路,促进模型认知等学科核心素养在化学课堂教学中落地。按照三元整合策略的教学流程进行建模教学,并以NH_(3)为例,在陌生情境中引导学生建立模型、完善模型运用模型,达成学生面对... 开展建模教学有助于学生形成解决陌生问题的认识角度和思路,促进模型认知等学科核心素养在化学课堂教学中落地。按照三元整合策略的教学流程进行建模教学,并以NH_(3)为例,在陌生情境中引导学生建立模型、完善模型运用模型,达成学生面对陌生问题能自觉运用“多角度预测反应”模型的目标,提升学生的整合思维和深度学习能力,为高三化学复习课提供教学范式,以期提升高三课堂教学的有效性。 展开更多
关键词 模型 建模教学 nh3 三元整合策略
原文传递
A highly sensitive electrochemical sensor based on poly(3-aminobenzoic acid)/graphene oxide-gold nanoparticles modified screen printed carbon electrode for paraquat detection
7
作者 Dechnarong Pimalai Thitirat Putnin Suwussa Bamrungsap 《Journal of Environmental Sciences》 2025年第2期139-150,共12页
Herein,a modified screen printed carbon electrode(SPCE)based on a composite material,graphene oxide-gold nanoparticles(GO-AuNPs),and poly(3-aminobenzoic acid)(P3ABA)for the detection of paraquat(PQ)is introduced.The m... Herein,a modified screen printed carbon electrode(SPCE)based on a composite material,graphene oxide-gold nanoparticles(GO-AuNPs),and poly(3-aminobenzoic acid)(P3ABA)for the detection of paraquat(PQ)is introduced.The modified electrode was fabricated by drop casting of the GO-AuNPs,followed by electropolymerization of 3-aminobenzoic acid to achieve SPCE/GO-AuNPs/P3ABA.The morphology and microstructural characteristics of the modified electrodes were revealed by scanning electron microscopy(SEM)for each step of modification.The composite GO-AuNPs can provide high surface area and enhance electroconductivity of the electrode.In addition,the presence of negatively charged P3ABA notably improved PQ adsorption and electron transfer rate,which stimulate redox reaction on the modified electrode,thus improving the sensitivity of PQ analysis.The SPCE/GOAuNPs/P3ABA offered a wide linear range of PQ determination(10^(−9)-10^(−4) mol/L)and low limit of detection(LOD)of 0.45×10^(−9) mol/L or 0.116μg/L,which is far below international safety regulations.The modified electrode showed minimum interference effect with percent recovery ranging from 96.5%to 116.1%after addition of other herbicides,pesticides,metal ions,and additives.The stability of the SPCE/GO-AuNPs/P3ABA was evaluated,and the results indicated negligible changes in the detection signal over 9 weeks.Moreover,this modified electrode was successfully implemented for PQ analysis in both natural and tapped water with high accuracy. 展开更多
关键词 PARAQUAT Electrochemical sensor Graphene oxide(GO) Gold nanoparticle(AuNP) Poly(3-aminobenzoic acid)(P3ABA)
原文传递
Simultaneous quantification of trace heavy metals in mushrooms using a three-dimensional highly reduced graphene oxide/Fe_(3)O_(4)nanocomposite-based electrochemical sensor
8
作者 Yiming Tian Pingsheng Zhong +2 位作者 Kai Zhou Lufei Zheng Jiali Ren 《Food Science and Human Wellness》 2025年第6期2268-2277,共10页
The accumulation of heavy metals in mushrooms has presented a significant risk to human health,underscoring the importance of devising a portable and cost-effective method for detecting heavy metals.Thus,we have devel... The accumulation of heavy metals in mushrooms has presented a significant risk to human health,underscoring the importance of devising a portable and cost-effective method for detecting heavy metals.Thus,we have developed an electrochemical sensor based on 3-dimensional highly reduced graphene oxide(3D-HRGO)in conjunction with Fe_(3)O_(4)nanoparticles,enabling the simultaneous quantification of Cd^(2+),Pb^(2+),Cu^(2+),and Hg^(2+).The 3D-HRGO/Fe_(3)O_(4)nano-particles material prepared in this study was characterized and confirmed by multiple techniques,then dispersed in a simple and environmental dispersant,consist of 75%ethanol and 0.1%Nafion,and coating on a glass carbon electrode(GCE)to preparing a 3D-HRGO/Fe_(3)O_(4)/GCE sensor.The limit of detection(LOD)of 3D-HRGO/Fe_(3)O_(4)/GCE sensor for Cd^(2+),Pb^(2+),Cu^(2+),and Hg^(2+)in simultaneous detection were 0.2,0.6,0.6,and 0.9μg/L,respectively.The sensor demonstrates exceptional stability,reproducibility,anti-interference,and recovery rate.Furthermore,the electrochemical sensor was employed to detect heavy metals in actual mushrooms and validated through conventional methodologies.This study represents the pioneering utilization of 3D-HRGO/Fe_(3)O_(4)as a foundational material for an electrochemical sensor capable of simultaneous detection of multiple metals,thereby advancing the progress of on-site and expeditious detection techniques. 展开更多
关键词 Electrochemical sensor 3D-HRGO/Fe_(3)O_(4)nanocomposite MUSHROOMS Heavy metals Rapid and simultaneous detection
在线阅读 下载PDF
Noncontact 3D gesture recognition enabled VR human-machine interface via electret-nanofiber-based triboelectric sensor
9
作者 Lijun Lu Jing Wu +5 位作者 Yujie Zhang Chang Liu Yun Hu Baojin Chen Yan Zhu Yanchao Mao 《Nano Research》 2025年第11期1189-1198,共10页
Virtual reality(VR)is an emerging communication means and creates extensive opportunities in interacting scenarios such as remote collaboration and metaverse.Human-machine interfaces(HMIs)play important roles in VR as... Virtual reality(VR)is an emerging communication means and creates extensive opportunities in interacting scenarios such as remote collaboration and metaverse.Human-machine interfaces(HMIs)play important roles in VR as they provide interaction platforms between users and virtual environments.However,traditional VR HMIs based on handheld devices or keyboards cannot recognize diverse three-dimensional(3D)gestures,which results in limited freedom of VR interactions.Here,we report a noncontact VR HMI enabled by an electret-nanofiber-based triboelectric sensor(ETS),which is fabricated by the electrospun polylactic acid/thermoplastic polyurethane(PLA/TPU)electret nanofiber film.The nanofiber structure of PLA/TPU electret enhanced the charge retention ability of triboelectric sensor and thus significantly improved its signal strength and stability.Integrated with a deep learning-based multilayer perceptron neural network,the ETS realizes the recognition of 18 different types of 3D gestures with a high average accuracy of 97.3%.An intelligent noncontact VR interactive system based on the ETS is further developed,which is used to manipulate game characters for performing different actions by 3D gestures.Compared with traditional VR HMIs,the proposed VR HMI based on PLA/TPU electret nanofiber film can detect various 3D gestures and offers a superior interaction freedom.This work for the first time introduces the triboelectric 3D gesture recognition method to the VR HMIs,and could make the interaction between human and virtual environments become more efficient and fascinating. 展开更多
关键词 virtual reality human-machine interfaces noncontact three-dimensional(3D)gesture recognition triboelectric sensors electret nanofiber films
原文传递
Highly selective QCM sensor based on functionalized hierarchical hollow TiO_(2)nanospheres for detecting ppb-level 3-hydroxy-2-butanone biomarker at room temperature
10
作者 Siqi Sun Cheng Zhao +6 位作者 Zhaohuan Zhang Ding Wang Xinru Yin Jingting Han Jinlei Wei Yong Zhao Yongheng Zhu 《Chinese Chemical Letters》 2025年第5期740-745,共6页
Listeria monocytogenes(LM)is a dangerous foodborne pathogen for humans.One emerging and validated method of indirectly assessing LM in food is detecting 3-hydroxy-2-butanone(3H2B)gas.In this study,the synthesis of 3-(... Listeria monocytogenes(LM)is a dangerous foodborne pathogen for humans.One emerging and validated method of indirectly assessing LM in food is detecting 3-hydroxy-2-butanone(3H2B)gas.In this study,the synthesis of 3-(2-aminoethylamino)propyltrimethoxysilane(AAPTMS)functionalized hierarchical hollow TiO_(2)nanospheres was achieved via precise controlling of solvothermal reaction temperature and post-grafting route.The sensors based on as-prepared materials exhibited excellent sensitivity(480 Hz@50 ppm),low detection limit(100 ppb),and outstanding selectivity.Moreover,the evaluation of LM with high sensitivity and specificity was achieved using the sensors.Such stable three-dimensional spheres,whose distinctive hierarchical and hollow nanostructure simultaneously improved both sensitivity and response/recovery speed dramatically,were spontaneously assembled by nanosheets.Meanwhile,the moderate loadings of AAPTMS significantly improved the selectivity of sensors.Then,the gas-sensing mechanism was explored by utilizing thermodynamic investigation,Gaussian 16 software,and in situ diffuse reflectance infrared transform spectroscopy,illustrating the weak chemisorption between the-NHgroup and 3H2B molecules.These portable sensors are promising for real-time assessment of LM at room temperature,which will make a magnificent contribution to food safety. 展开更多
关键词 Hierarchical hollow TiO_(2)nanospheres AAPTMS functionalization Gas sensor 3-Hydroxy-2-butanone detection Sensing mechanism
原文传递
Additively manufactured porous elastomeric sensors for simultaneous high-sensitivity pressure detection and wide-dynamicrange motion tracking
11
作者 Aoxi Yu Xiaoguang Hu +6 位作者 Shen Yang Borui Zhang Yuzhe Gu Mingye Zhu Yanling Zhuang Shujuan Liu Qiang Zhao 《Nano Research》 2025年第11期1143-1153,共11页
Flexible pressure sensors are indispensable components in wearable electronics for health monitoring and exercise management.However,existing pressure sensors face a critical trade-off between high sensitivity and wid... Flexible pressure sensors are indispensable components in wearable electronics for health monitoring and exercise management.However,existing pressure sensors face a critical trade-off between high sensitivity and wide detection range.Herein,we present novel flexible pressure sensors based on poly(3,4-ethylenedioxy-thiophene):poly(styrene sulfonate)(PEDOT:PSS)and thermoplastic polyurethane(TPU),fabricated by direct ink writing(DIW)technology with a sacrificial template strategy.The integration of the high conductivity of PEDOT:PSS,the mechanical durability of TPU,and the engineered hierarchical porous structure with irregular surface topography enables the PEDOT:PSS/TPU-based pressure sensors(PPSs)to achieve an exceptionally wide detection range(0-1044 kPa),high sensitivity(30.178 kPa^(−1)),and outstanding cycling stability(over 10,000 cycles).Leveraging these advantages,the sensors have demonstrated exceptional performance in precise physiological monitoring,effective pressure mapping through sensor arrays,and reliable operation in extreme environments(e.g.,cryogenic conditions at−196°C and underwater).Furthermore,the successful integration with LED circuits and wireless Bluetooth systems highlights their potential for next-generation wearable electronics and personalized healthcare monitoring. 展开更多
关键词 flexible pressure sensor direct ink writing poly(3 4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS) wearable electronics
原文传递
Pt/Ti_(3)C_(2)electrode material used for H_(2)S sensor with low detection limit and high stability
12
作者 Huakang Zong Xinyue Li +4 位作者 Yanlin Zhang Faxun Wang Xingxing Yu Guotao Duan Yuanyuan Luo 《Chinese Chemical Letters》 2025年第5期600-605,共6页
Traditional Pt/C electrode materials are prone to corrosion and detachment during H_(2)S detection,leading to a decrease in fuel cell-type sensor performance.Here,a high-performance H_(2)S sensor based on Pt loaded Ti... Traditional Pt/C electrode materials are prone to corrosion and detachment during H_(2)S detection,leading to a decrease in fuel cell-type sensor performance.Here,a high-performance H_(2)S sensor based on Pt loaded Ti_(3)C_(2)electrode material with-O/-OH terminal groups was designed and prepared.Experimental tests showed that the Pt/Ti_(3)C_(2)sensor has good sensitivity(0.162μA/ppm)and a very low detection limit to H_(2)S(10 ppb).After 90 days of stability testing,the response of the Pt/Ti_(3)C_(2)sensor shows a smaller decrease of 2%compared to that of the Pt/C sensor(22.9%).Meanwhile,the sensor also has high selectivity and repeatability.The density functional theory(DFT)calculation combined with the experiment results revealed that the improved H_(2)S sensing mechanism is attributed to the fact that the strong interaction between Pt and Ti_(3)C_(2)via the Pt-O-Ti bonding can reduce the formation energy of Pt and Ti_(3)C_(2),ultimately prolonging the sensor’s service life.Furthermore,the catalytic property of Pt can decrease the adsorption energy and dissociation barrier of H_(2)S on Pt/Ti_(3)C_(2)surface,greatly enhance the ability to generate protons and effectively transfer charges,realizing good sensitivity and high selectivity of the sensor.The sensor works at room temperature,making it very promising in the field of H_(2)S detection in future. 展开更多
关键词 H_(2)S sensor Pt/Ti_(3)C_(2) Low detection limit Long term stability Density functional theory calculation
原文传递
A novel green phosphor Ba_(2)Sc_(2)((BO_(3))_(2)B_(2)O_(5)):Ce^(3+)for high color rendering index full-spectrum lighting and low-temperature sensors
13
作者 Pan Liang Hongshu Zhang +7 位作者 Yingying Xue Saying Li Hongsheng Huang Xin Li Xuxiang Lin Yuxin Zhang Lianqing Li Zhihong Liu 《Journal of Rare Earths》 2025年第6期1150-1160,I0003,共12页
The utilization of phosphors that achieve full-spectrum lighting has emerged as a prevailing trend in the advancement of white light-emitting diode(WLED)lighting.In this study,we successfully prepared a novel green ph... The utilization of phosphors that achieve full-spectrum lighting has emerged as a prevailing trend in the advancement of white light-emitting diode(WLED)lighting.In this study,we successfully prepared a novel green phosphor Ba_(2)Sc_(2)((BO_(3))_(2)B_(2)O_(5)):Ce^(3+)(BSBO:Ce^(3+))that can be utilized for full-spectrum lighting and low-temperature sensors.BSBO:Ce^(3+)exhibits a broad-band excitation spectrum centered at 410 nm,and a broad-band emission spectrum centered at 525 nm.The internal and external quantum efficiencies of BSBO:Ce^(3+)are 99%and 49%,respectively.The thermal stability of BSBO:Ce^(3+)can be improved by substituting partial Sc atoms with smaller cations.The thermal quenching mechanism of BSBO:Ce^(3+)and the lattice occupancy of Ce ions in BSBO are discussed in detail.Furthermore,by combining the green phosphor BSBO:Ce^(3+),the commercial blue phosphor and the red phosphor on a 405 nm chip,a white light source was obtained with a high average color rendering index(CRI)of 96.6,a low correlated color temperature(CCT)of 3988 K,and a high luminous efficacy of 88.0 Im/W.The lu-minous efficacy of the WLED exhibits negligible degradation during the 1000 h light aging experiment.What's more,an emission peak at 468 nm appears when excited at 352 nm and 80 K,however,the relative intensity of the peaks at 468 and 525 nm gradually weakens with increasing temperature,indicating the potential of this material as a low-temperature sensor. 展开更多
关键词 Green phosphor Ba_(2)Sc_(2)(BO_(3)_(2)B_(2)O_(5)):Ce^(3+) Fullspectrum lighting Low-temperature sensor High color rendering index Rare earths
原文传递
A fully integrated electronic fabric-enabled multimodal flexible sensors for real-time wireless pressure-humidity-temperature monitoring
14
作者 Yunlong Zhao Yangbo Yuan +7 位作者 Haiyan Zhang Zijian Chen Haitao Zhao Guirong Wu Weihao Zheng Chenyang Xue Zongyou Yin Libo Gao 《International Journal of Extreme Manufacturing》 CSCD 2024年第6期548-560,共13页
Real-time physiological information monitoring can predict and prevent disease, or improve treatment by early diagnosis. A comprehensive and continuous monitoring of human health requires highly integrated wearable an... Real-time physiological information monitoring can predict and prevent disease, or improve treatment by early diagnosis. A comprehensive and continuous monitoring of human health requires highly integrated wearable and comfortable sensing devices. To address this need, we propose a low-cost electronic fabric-enabled multifunctional flexible sensing integration platform that includes a flexible pressure sensor for monitoring postural pressure, a humidity sensor for monitoring the humidity of the skin surface, and a flexible temperature sensor for visualizing the ambient temperature around the human body. Thanks to the unique rough surface texture, hierarchical structure, and robust electromechanical features of the MXene-modified nonwoven fabrics, the flexible pressure sensor can achieve a monitoring sensitivity of 1529.1 kPa~(-1) and a pressure range of 150 kPa, which meets the demand for human pressure detection. In addition, the unique porous structure of the fabric and the stacked multilayer structure of MXene enable the humidity sensor to exhibit extremely high monitoring sensitivity, even through clothing, and still be able to detect the humidity on the skin surface.Temperature sensors based on screen-printed thermochromic liquid crystals enable visual monitoring in the range of 0℃–65℃. Through further integration with flexible printed circuit board circuits, we demonstrate a proof-of-concept device that enables real-time monitoring of human physiological information such as physical pressure, humidity, and ambient temperature environment, suggesting that the device provides an excellent platform for the development of commercially viable wearable healthcare monitors. 展开更多
关键词 wearable sensor non-invasive physiological monitoring MXene(Ti_3C_2T_x) thermochromic liquid crystals(TLCs) integrated sensor patch
在线阅读 下载PDF
pH值对好氧堆肥过程中NH3挥发和氮素转化的影响 被引量:6
15
作者 苏杨琴 邱慧珍 +1 位作者 成志远 李云 《国土与自然资源研究》 2024年第1期57-62,共6页
为揭示不同pH值对好氧堆肥中NH_(3)挥发和氮素化合物转化的影响,设置5个处理(T1:对照;T2~T4:pH值分别为8.5、7.5和6.5;T5:酸性添加剂,10%过磷酸钙),研究不同pH值和酸性添加剂对好氧堆肥中NH_(3)挥发和氮素化合物转化的影响。试验结果表... 为揭示不同pH值对好氧堆肥中NH_(3)挥发和氮素化合物转化的影响,设置5个处理(T1:对照;T2~T4:pH值分别为8.5、7.5和6.5;T5:酸性添加剂,10%过磷酸钙),研究不同pH值和酸性添加剂对好氧堆肥中NH_(3)挥发和氮素化合物转化的影响。试验结果表明,堆肥的高温期氨挥发量占总挥发量的95%以上。降低堆体pH值可以有效降低氨挥发,且初始pH值越低,氨挥发量越少。至堆肥结束,与T1处理相比,T2~T4处理的NH_(3)累计排放量分别减少了35.8%、66.93%和84.48%。添加过磷酸钙能使堆体pH值降低0.03~0.09个单位,使氨挥发减少62.42%。至堆肥结束,T1、T2、T3和T5处理NH_(4)^(+)-N含量均下降到0.04 g·kg^(-1)以下的水平,而T4处理NH_(4)^(+)-N含量最大为0.17 g·kg^(-1)。说明T4处理有利于促进反硝化作用的进行。T3处理的NO_(3)^(-)-N和酸解有机氮含量均高于T1、T2和T4处理。说明T3处理有利于促进硝化作用和氨同化作用的进行。与T1处理相比,T5处理NH_(4)^(+)-N含量增加了8.56%,NO_(3)^(-)-N含量减少了30%,酸解有机氮含量增加了2.52%,这说明,过磷酸钙的添加有利于促进氨同化作用的进行,但是抑制了反硝化作用的进行。 展开更多
关键词 PH值 酸性添加剂 好氧堆肥 nh3挥发 氮素转化
在线阅读 下载PDF
Al-doped ZnO/WO_(3) heterostructure films prepared by magnetron sputtering for isopropanol sensors 被引量:3
16
作者 Wei-Xiang Gao Xue-Ting Chang +5 位作者 Xiao-Jie Zhu Jun-Feng Li Ying-Chang Jiang Dong-Sheng Wang Chuan-Xiao Yang Shi-Bin Sun 《Rare Metals》 SCIE EI CAS CSCD 2024年第1期247-256,共10页
Metal oxide semiconductors(MOSs) are ideal sensing materials for detecting volatile organic compounds due to their low cost, diversity, high stability, and ease of production. However, it remains a grand challenge to ... Metal oxide semiconductors(MOSs) are ideal sensing materials for detecting volatile organic compounds due to their low cost, diversity, high stability, and ease of production. However, it remains a grand challenge to develop the MOSs-based gas sensors for sensing isopropanol with desired performance via a simple, effective,and controllable method. Herein, we reported the preparation of the Al-doped Zn O(AZO)/WO_(3) heterostructure films by directly depositing the AZO coating onto the WO_(3) coating using a strategy of magnetron sputtering. The AZO/WO_(3) heterostructure films were constructed by numbers of irregular nanoparticles that were interconnected with each other. The AZO/WO_(3) heterostructure films-based gas sensors exhibited excellent isopropanolsensing performance with high response, promising selectivity, low detection limit, fast response rate, wide detection range, and ideal reproducibility. The promising isopropanol-sensing performance of the AZO/WO_(3) heterostructure films arises mainly from their high uniformity, unique microstructures with high surface roughness,and the construction of the heterostructure between the AZO and WO_(3) coatings. This work provides a versatile approach to prepare the MOSs-based heterostructure films for assembling the gas sensors. 展开更多
关键词 Metal oxide semiconductors Gas sensors Aldoped ZnO/WO_(3) Heterostructure films ISOPROPANOL Magnetron sputtering
原文传递
NH3/CH4混合燃料层流火焰速度的数值分析及其反应机理的优化
17
作者 王津铭 王景甫 +1 位作者 陈颖 陈纪全 《可持续能源》 2024年第1期1-20,共20页
NH3作为一种无碳燃料,且具有较长的应用历史、较高的市场成熟度和较完整的产业链,因此在推动全球低碳发展中具有很大的发展前景。为了解决NH3在燃烧时火焰传播速度较慢的问题,可行的方法是将NH3与CH4混合燃烧。针对NH3/CH4混合燃烧的数... NH3作为一种无碳燃料,且具有较长的应用历史、较高的市场成熟度和较完整的产业链,因此在推动全球低碳发展中具有很大的发展前景。为了解决NH3在燃烧时火焰传播速度较慢的问题,可行的方法是将NH3与CH4混合燃烧。针对NH3/CH4混合燃烧的数值模拟研究时采用的反应机理比较多样且都存在相对误差的问题,对NH3/CH4混合燃料的层流燃烧速度进行模拟并通过反应灵敏度等方法分析了重要影响因素。结果表明燃料CH4的添加可有效使NH3的层流火焰速度线性增加,燃烧强度显著提升。同时发现层流火焰速度在很大程度上受火焰中自由基O、H、OH数量以及基元反应H + O2 O + OH反应速率的影响,随CH4加入火焰中的O、H、OH的摩尔分数也随之增大,因此进一步提高NH3的层流火焰速度。此外通过敏感性分析以及火焰结构分析发现基元反应的参数设置是各个机理模拟产生差异的根本原因,因此本研究基于模拟表现最好Okafor机理,根据其他常用机理的参数设置和实验数据形成了优化机理Okafor-Modified,与实验结果的平均相对误差在10%内。 展开更多
关键词 二元燃料nh3/CH4 层流燃烧速度 机理优化
在线阅读 下载PDF
柴油机低温工况下SCR尿素喷射及NH3分布特性研究 被引量:1
18
作者 和志高 杨树启 +2 位作者 郭宇辰 杨继孔 杨辉 《农业装备与车辆工程》 2024年第7期130-134,138,共6页
在柴油机加装后处理系统DOC+CDPF+SCR试验研究基础上,构建并开展SCR三维CFD数值模拟,研究尿素喷射过程中液滴的生成扩散和水解蒸发,对比分析不同低温工况下NH_(3)分布特性和NH_(3)分布均匀度对NOX转化效率的影响。结果表明,在低温工况... 在柴油机加装后处理系统DOC+CDPF+SCR试验研究基础上,构建并开展SCR三维CFD数值模拟,研究尿素喷射过程中液滴的生成扩散和水解蒸发,对比分析不同低温工况下NH_(3)分布特性和NH_(3)分布均匀度对NOX转化效率的影响。结果表明,在低温工况下随着尿素喷射量增大,混合器前后区域催化器内表面形成较多的尿素壁膜,持续尿素喷射易产生尿素结晶;低温工况混合器和整流器对气体流动有明显的扩散作用,但随着气流量增大,NH_(3)分布集中在载体外侧区域,导致外侧发生NH_(3)逃逸量较高;在不同低温工况下,载体入口面NH_(3)分布均匀度的增大,有效提高了NOX转化效率,减小了NH_(3)逃逸量及低温下尿素结晶的可能性。 展开更多
关键词 低温工况 尿素壁膜 nh3分布均匀度 尿素结晶
在线阅读 下载PDF
RSSI-Based 3D Wireless Sensor Node Localization Using Hybrid T Cell Immune and Lotus Optimization
19
作者 Weiwei Hu Kiran Sree Pokkuluri +3 位作者 Rajesh Arunachalam Bander A.Jabr Yasser A.Ali Preethi Palanisamy 《Computers, Materials & Continua》 SCIE EI 2024年第12期4833-4851,共19页
Wireless Sensor Network(WSNs)consists of a group of nodes that analyze the information from surrounding regions.The sensor nodes are responsible for accumulating and exchanging information.Generally,node local-ization... Wireless Sensor Network(WSNs)consists of a group of nodes that analyze the information from surrounding regions.The sensor nodes are responsible for accumulating and exchanging information.Generally,node local-ization is the process of identifying the target node’s location.In this research work,a Received Signal Strength Indicator(RSSI)-based optimal node localization approach is proposed to solve the complexities in the conventional node localization models.Initially,the RSSI value is identified using the Deep Neural Network(DNN).The RSSI is conceded as the range-based method and it does not require special hardware for the node localization process,also it consumes a very minimal amount of cost for localizing the nodes in 3D WSN.The position of the anchor nodes is fixed for detecting the location of the target.Further,the optimal position of the target node is identified using Hybrid T cell Immune with Lotus Effect Optimization algorithm(HTCI-LEO).During the node localization process,the average localization error is minimized,which is the objective of the optimal node localization.In the regular and irregular surfaces,this hybrid algorithm effectively performs the localization process.The suggested hybrid algorithm converges very fast in the three-dimensional(3D)environment.The accuracy of the proposed node localization process is 94.25%. 展开更多
关键词 sensor node localization received signal strength indicator 3D wireless sensor network deep neural network average localization error and hybrid T cell immune with lotus effect optimization algorithm
在线阅读 下载PDF
Nanodiamond/Ti_(3)C_(2) MXene-coated quartz crystal microbalance humidity sensor with high sensitivity and high quality factor
20
作者 Yao Yao Qiao Chen +5 位作者 Yan-Qi Li Xian-He Huang Wei-Wei Ling Zhe-MiaoXie Jia-QiWang Chang-Ming Chen 《Rare Metals》 SCIE EI CAS CSCD 2024年第6期2719-2729,共11页
To address the challenge of achieving both high sensitivity and a high quality factor in quartz crystal microbalance(QCM)humidity sensors,a nanodiamond(ND)/Ti_(3)C_(2)MXene composite-coated QCM humidity sensor was fab... To address the challenge of achieving both high sensitivity and a high quality factor in quartz crystal microbalance(QCM)humidity sensors,a nanodiamond(ND)/Ti_(3)C_(2)MXene composite-coated QCM humidity sensor was fabricated.The material characteristics of ND,Ti_(3)C_(2)MXene,and ND/Ti_(3)C_(2)MXene composite were analyzed by transmission electron microscopy(TEM)and Fourier transform infrared(FTIR)spectroscopy.The experimental results demonstrated that the hydrophilic ND nanoparticles coated on Ti_(3)C_(2) MXene nanosheet prevented the self-stacking of Ti_(3)C_(2)MXene and enhanced the sensitivity of Ti_(3)C_(2) MXene-based QCM humidity sensor.Moreover,the high mechanical modulus of Ti_(3)C_(2) MXene material helped ND/Ti_(3)C_(2)MXene composite-coated QCM humidity sensor to achieve a high quality factor(>20,000).ND/Ti_(3)C_(2)MXene compositecoated QCM humidity sensor exhibited a sensitivity of 82.45 Hz/%RH,a humidity hysteresis of 1.1%RH,fast response/recovery times,acceptable repeatability,and good stability from 11.3%RH to 97.3%RH.The response mechanism of ND/Ti_(3)C_(2) MXene composite-coated QCM humidity sensor was analyzed in combination with a bi-exponential kinetic adsorption model.Finally,the potential application of ND/Ti_(3)C_(2)MXene composite-coated QCM humidity sensor was demonstrated through its frequency response to wooden blocks with different moisture contents. 展开更多
关键词 Humidity sensor Quartz crystal microbalance NANODIAMOND Ti_(3)C_(2)MXene High quality factor
原文传递
上一页 1 2 168 下一页 到第
使用帮助 返回顶部