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Toward practical gas sensing with rapid recovery semiconducting carbon nanotube film sensors

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Science China(Information Sciences) 2022年第6期65卷 226-233页

作者： Fangfang LIU Mengmeng xiao Yongkai NING Shaoyuan ZHOU Jianping HE Yanxia LIN zhiyong ZHANG Hunan Institute of Advanced Sensing and Information Technology Xiangtan University Institute of Microelectronics of Chinese Academy of Sciences and University of Chinese Academy of Sciences Key Laboratory for the Physics and Chemistry of Nanodevices and Center for Carbon-based Electronics Department of Electronics Peking University

Nanomaterials have been considered as promising materials to construct highly sensitive and miniaturized gas sensors due to their high ratio of surface to volume, but almost all of the reported nanomaterials based resistive gas sensors are difficult to use in the practical system mainly owing to the long recovery time and non-equilibrium state at room temperature. Here, we demonstrate a gate assistant technology to realize the rapid recovery to an equilibrium state in semiconducting carbon nanotube(CNT) thin-film gas sensors and promote the CNT-based gas sensors to reach the practical application level. Specifically, we construct highly uniform gas sensors based on semiconducting solution-derived CNT film and accelerate the gas molecules desorption by applying a voltage on the back gate(substrate), which is named gate-assistant recovery technology. By combining the gate-assistant recovery technology and a modified concentration calculation method, highly reproducible detection systems have been realized by using a custom-built printed circuit board(PCB) based data acquisition circuits to execute a real-time rapid detection of H2 in the air at room temperature, and especially exhibits a record response time of 9 s and recovery time of 50 s under a resolution of 10 ppm, which outperformed previous low dimensional nanomaterials based portable H2 detection systems. The gate-assistant rapid recovery and related concentration calculation technologies are helpful to promote the nanomaterials-based gas sensors to practical application for highly sensitive online gas detection.

关键词： carbon nanotube gas sensor thin-film transistors rapid recovery

糖尿病合并新型冠状病毒S蛋白感染小鼠病理生理特征

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中国药理学与毒理学杂志 2024年第6期38卷 410-419页

作者：苏小月李静璇林颖张永祥肖智勇周文霞军事医学研究院国家安全特需药品全国重点实验室北京100850

目的建立糖尿病(DM)合并新型冠状病毒(SARS-CoV-2)感染小鼠模型,研究DM合并SARS-CoV-2感染病程发展中的重要病理生理变化。方法将野生型(WT)小鼠和由细胞角蛋白18基因启动子驱动的人血管紧张素转化酶2受体(K18-hACE2,简称hACE2)的转基... 详细信息

目的建立糖尿病(DM)合并新型冠状病毒(SARS-CoV-2)感染小鼠模型,研究DM合并SARS-CoV-2感染病程发展中的重要病理生理变化。方法将野生型(WT)小鼠和由细胞角蛋白18基因启动子驱动的人血管紧张素转化酶2受体(K18-hACE2,简称hACE2)的转基因小鼠分别随机分为溶剂对照组、DM组、SARS-CoV-2病毒刺突蛋白感染(S)组以及DM合并S蛋白感染(DM+S)组,每组10~12只。除溶剂对照组及S组外,其余组通过10周高脂饮食后连续3 d ip给予链脲佐菌素(STZ)40 mg·kg^(-1)诱导DM症状,溶剂对照组及S组给予等体积0.1 mol·L^(-1)柠檬酸钠缓冲液。在此基础上,S组及DM+S组小鼠经鼻腔滴入15μg SARS-CoV-2 S蛋白与1 g·L^(-1)聚肌胞苷酸(Poly[I:C])的混合溶液50μL,溶剂对照组滴鼻给予等体积无菌水。在高脂喂养第6周和ip给予STZ 1周后,以口服葡萄糖耐量实验评价小鼠糖耐量水平及胰岛β细胞功能。高脂喂养第6周至ip给予STZ 2周后,每周用血糖仪检测小鼠随机血糖及空腹血糖。DM小鼠S蛋白感染前及感染24,48和120 h后,每组取3只小鼠颌下静脉取血后处死并取肺组织,采用苏木精-伊红染色法观察合并S蛋白感染前后的肺组织病理改变。S组小鼠在感染S蛋白前及感染6,24,48,72和120 h后采血,Luminex液相芯片技术检测小鼠血浆细胞因子白细胞介素1β(IL-1β)、IL-2、IL-6、IL-10、IL-17、干扰素诱导蛋白10(IP-10)、干扰素γ(IFN-γ)、肿瘤坏死因子α(TNF-α)、单核细胞趋化蛋白1(MCP-1)和粒细胞集落刺激因子(G-CSF)水平,ELISA检测血浆硫酸乙酰肝素(HS)水平;将细胞因子水平、HS水平与小鼠感染S蛋白后的肺部病理损伤程度进行Spearman相关性分析。结果STZ合并高脂饮食可诱导小鼠DM样表现,hACE2-DM组随机血糖(P<0.01)和1周后的空腹血糖(P<0.05)均显著高于WT-DM组,且hACE2-DM小鼠胰岛功能损伤程度显著高于WT-DM小鼠(P<0.05)。与DM组相比,DM+S组小鼠均表现出更严重的肺部病理变化,并伴有大量炎症浸润和肺间质增厚。与溶剂对照组相比,S蛋白感染6 h,WT-S组小鼠血浆中促炎细胞因子G-CSF,IL-6和IP-10均显著升高(P<0.01),S蛋白感染24 h,促炎细胞因子IL-17和抗炎细胞因子IL-10均显著升高(P<0.05);S蛋白感染6 h,hACE2-S组血浆中促炎细胞因子IL-1β,IL-6,TNF-α,MCP-1,G-CSF和IP-10均显著升高(P<0.05,P<0.01);WT-DM+S组和hACE2-DM+S组IL-17分别在S蛋白感染24和6 h显著升高(P<0.01,P<0.05),hACE2-DM+S组IFN-γ和IL-1β延迟至48 h显著升高(P<0.05,P<0.01),MCP-1延迟至72 h显著升高(P<0.05)。与溶剂对照组相比,S蛋白感染6和24 h后,WT-S组血浆中HS水平显著升高(P<0.05,P<0.01),48 h开始降低;同时,与WT-S组相比,感染6 h后,WT-DM+S组HS水平略升高,24 h出现降低;hACE2-S组HS水平于24 h显著升高(P<0.01),且在S蛋白感染24,48和120 h后与WT-S组基本持平;S蛋白感染6,24和48 h后,hACE2-DM+S组血浆HS水平均显著升高(P<0.01,P<0.05),升高持续时间较其S组长。小鼠血浆中IL-1β,IL-10,MCP-1,IP-10,G-CSF以及HS水平与DM+S小鼠肺损伤程度呈正相关(P<0.05,P<0.01)。结论本研究建立的DM合并SARS-CoV-2 S蛋白感染小鼠模型能成功模拟临床患者的部分病理生理特征,主要表现为较单纯感染免疫反应钝化,HS水平升高且持续时间较长。IL-1β,IL-10,MCP-1,IP-10,G-CSF以及HS可能有助于及时了解DM合并SARS-CoV-2感染患者的病程。

关键词：新型冠状病毒感染 SARS-CoV-2 S蛋白糖尿病动物模型细胞因子硫酸乙酰肝素

A型肉毒素治疗肌源性颞下颌关节紊乱病的研究进展

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口腔疾病防治 2024年第6期32卷 470-477页

作者：陈奕帆汤良晨陈敏儿张萧唐贶昀李志勇浙江大学医学院附属口腔医院口腔颌面外科浙江大学口腔医学院浙江省口腔疾病临床医学研究中心浙江省口腔生物医学研究重点实验室浙江大学癌症研究院口腔生物材料与器械浙江省工程研究中心浙江杭州310006

肌源性颞下颌关节紊乱病(myogenous temporomandibular disorders,M⁃TMD)是颞下颌关节紊乱病(temporomandibular disorders,TMD)的主要亚型之一,肌痛为最典型表现,发病率呈逐年上升的趋势。A型肉毒素(botulinum toxin type A,BTX⁃A)是一种由肉毒杆菌产生的强效神经毒素,可抑制乙酰胆碱从突触前膜释放,从而阻断神经肌肉接头信号传导,使得注射区肌肉麻痹,BTX⁃A在口腔颌面部非美容性的应用是未来的研究热点。近年来越来越多研究聚焦于BTX⁃A用于M⁃TMD的治疗,文献回顾结果显示,在疼痛部位单次注射适宜剂量(单侧10~50 U)的BTX⁃A可在3~6个月内持续改善肌痛症状,必要时需重复注射。注射后常见不良反应如咀嚼无力、面瘫等均为暂时性,并可通过规范操作规避其发生,但目前临床仍缺少标准化的注射技术指南。

关键词： A型肉毒素肌源性颞下颌关节病颞下颌关节紊乱病咀嚼肌肌痛乙酰胆碱副作用临床应用

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Assessment of the Mechanical Properties of Carbon-Fiber Heating Cables in Snow and Ice Melting Applications

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Fluid Dynamics & Materials Processing 2023年第9期19卷 2267-2288页

作者： zhiyong Yang Jiacheng Zhang Henglin xiao Zhi Chen Tian Bao Yin Liu School of Civil Engineering and Environment Hubei University of TechnologyWuhan430068China Xiangyang Industrial Institute of Hubei University of Technology Xiangyang441100China

The use of carbon-ﬁber heating cables(CFHC)to achieve effective melting of snow and ice deposited on roads is a method used worldwide.In this study,tensile and compressive tests have been conducted to analyze the mechan-ical properties of the CFHC and assess whether the maximum tensile and compressive strengths can meet the pavement design speciﬁcations.In order to study the aging produced by multiple cycles of heating and cooling,in particular,the CFHC was repeatedly heated in a cold chamber with an ambient temperature ranging between-20℃ and+40℃.Moreover,to evaluate how the strength of the pavement is affected by its presence,the CFHC was embedded at different depths and concrete blocks with different curing ages were subjected to relevant com-pression and splitting tensile tests.Numerical simulations based on the ANSYS software have also been performed and compared with the outcomes of the static loading tests.The results show that the CFHC embedded in the concrete does not affect the compressive splitting tensile strengths of the pavement.Overall,the CFHC meets the conditions required for continued use in road ice melting applications.

关键词： Carbon fiber cable snow and ice melting concrete pavement compressive strength splitting tensile strength

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白背枫的化学成分研究

中草药 2024年第1期55卷 38-42页

作者：肖碟许浩楠王浩鑫陈林谢红茜丁祖霄左爱学江志勇云南中医药大学云南省高校民族药现代研究重点实验室云南昆明650500 昆明医科大学药学院云南昆明650500

目的对白背枫Buddleja asiatica进行化学成分研究。方法采用正反相硅胶柱色谱、MCI、Sephadex LH-20柱色谱以及半制备高效液相色谱等分离手段进行分离纯化,根据1D和2D NMR,MS等波谱数据和理化性质对化合物进行结构鉴定。采用分光光度... 详细信息

目的对白背枫Buddleja asiatica进行化学成分研究。方法采用正反相硅胶柱色谱、MCI、Sephadex LH-20柱色谱以及半制备高效液相色谱等分离手段进行分离纯化,根据1D和2D NMR,MS等波谱数据和理化性质对化合物进行结构鉴定。采用分光光度发测定化合物对α-葡萄糖苷酶的抑制活性。结果从白背枫茎叶90%甲醇提取物的二氯甲烷萃取部分中分离鉴定了9个化合物,分别为(S)-1,4-di(benzo[d][1,3]dioxol-5-yl)-3-(hydroxymethyl)butan-2-one(1)、meridinol(2)、3,3’-bis(3,4-dihydro-4-hydroxy-6-methoxy-2H-1-benzopyran)(3)、protocatechualdehyde(4)、丁香醛(5)、3,4-二甲氧基桂皮酸(6)、4-甲氧基桂皮酸(7)、异东莨菪内酯(8)、松柏醛(9)。化合物3表现出一定的α-葡萄糖苷酶抑制作用,IC50值为41.3μmol/L。其余化合物未见α-葡萄糖苷酶抑制活性。结论化合物1为1个新的降木脂素,命名为白背枫酮。除化合物6外,其余化合物均为首次从该植物中分离得到。化合物3有中等程度的α-葡萄糖苷酶抑制活性。

关键词：白背枫醉鱼草属降木脂素白背枫酮丁香醛 4-甲氧基桂皮酸异东莨菪内酯松柏醛

An injectable mPEG-PDLLA microsphere/PDLLA-PEG-PDLLA hydrogel composite for soft tissue augmentation

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Chinese Chemical Letters 2022年第5期33卷 2486-2490页

作者： Yue Pan Yao xiao Ying Hao Kun Shi Meng Pan zhiyong Qian State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy West China HospitalWest China Medical SchoolSichuan UniversityChengdu 610041China

Injectable filling material is a simple and efficient method for soft tissues reconstruction and is extremely popular in not only plastic surgery but also cosmetic industry.However,there is a lack of soft tissue fillers with perfect performance on the market currently.Here,we constructed a new microsphere/hydrogel composite and evaluated its potential as a candidate for soft tissue augmentation.mPEG-PDLLA micro-spheres were prepared by utilizing a SPG membrane emulsifier which endowed microspheres with good sphericity and particle size uniformity.PDLLA-PEG-PDLLA hydrogel which shared the same component with the mPEG-PDLLA copolymer acted as a carrier and fixed the microspheres at the injected sites.The mPEG-PDLLA microsphere/PDLLA-PEG-PDLLA hydrogel composite was flowable in room temperature and transformed into gel after being heated to body temperature.This feature is convenient for subcutaneous filling.In vivo assessment on mice showed good safety profile of the composite.Moreover,the density of collagen fibers increased over 13 weeks.Overall,this biocompatible microsphere/hydrogel composite involves simple component and no extra crosslinking agents,and has the ability to stimulate collagen production,thus,may be a candidate for soft tissue augmentation.

关键词： Soft tissue augmentation mPEG-PDLLA Microspheres Hydrogel Collagenogenesis

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波形褶皱滤袋脉冲喷吹清灰性能分析

安全与环境学报 2024年第5期24卷 1758-1767页

作者：党小庆赵志宏王赫韩笑徐辉蒋孟杰张涛叶志勇陈俞百西安建筑科技大学环境与市政工程学院陕西省环境工程重点实验室西安710055 上海袋式除尘配件有限公司上海200241 抚顺天宇滤材有限公司辽宁抚顺113122

针对褶皱滤袋的波形结构影响滤袋表面静压的均匀分布,脉冲清灰性能不明确的问题,选取8褶、7 m长的波形褶皱滤袋,首先通过物理试验研究滤袋沿袋长方向不同截面的壁面峰值压力分布规律,后在验证数值模拟分析方法的可靠性和准确性的基础上... 详细信息

针对褶皱滤袋的波形结构影响滤袋表面静压的均匀分布,脉冲清灰性能不明确的问题,选取8褶、7 m长的波形褶皱滤袋,首先通过物理试验研究滤袋沿袋长方向不同截面的壁面峰值压力分布规律,后在验证数值模拟分析方法的可靠性和准确性的基础上,通过数值模拟模型优化和正交试验分析各因素对清灰性能的影响。结果表明:在喷嘴直径22 mm、喷吹时间100 ms,不同喷吹压力和喷吹距离条件下,滤袋沿袋长方向上的壁面峰值压力的变化趋势与圆筒形滤袋相同;距袋口1~7 m,滤袋无明显变形,同一截面波峰、波中、波谷位置的压力相对偏差在±10%以内。等流通面积法优化的三维模型和二维轴对称模型的数值计算结果和试验结果更接近,在对比壁面峰压、诱导气流的基础上,证明了其优化分析褶皱滤袋的清灰性能的合理性与可行性。正交试验分析各因素的影响程度从大到小依次为喷吹压力、滤袋长度、喷吹距离、褶数和喷吹时间;6~12褶为最佳范围,褶数增加,峰值压力呈下降趋势。研究成果可为波形褶皱滤袋的喷吹参数设计和结构优化提供参考依据。

关键词：安全卫生工程技术波形褶皱滤袋物理模型试验数值模拟正交试验滤袋壁面峰值压力

Synergistic engineering of cobalt selenide and biomass-derived S,N,P co-doped hierarchical porous carbon for modulation of stable Li-S batteries

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Journal of Materials Science & Technology 2023年第3期134卷 11-21页

作者： Yang Lin Song He zhiyong Ouyang Jianchao Li Jie Zhao Yanhe xiao Shuijin Lei Baochang Cheng Nanoscale Science and Technology Laboratory Institute for Advanced StudyNanchang UniversityNanchang 330031China School of Physics and Materials Nanchang UniversityNanchang 330031China

Hierarchical porous carbon co-doped with heterogeneous atoms has attracted much attention thanks to sizable internal void space accommodating electrolyte,high-density microporous structure physically con-fining polysulfides(LPS),and heterogeneous atoms serving as active sites to capture LPS.However,solely relying on carbon material defects to capture LPS proves ineffective.Hence,metal compounds must be introduced to chemisorb LPS.Herein,cobalt ions are in-situ grown on the polydopamine layer coated on the surface of biomass-derived S,N,P co-doped hierarchical porous carbon(SNP-PC).Then a layer of nitrogen-doped porous carbon(MPC)dotted with CoSe nanoparticles is acquired by selenizing.Thus,a strong-polar/weak-polar composite material of SNP-PC studded with CoSe nanoparticles is obtained(SNP-PC@MPC@CoSe).Button cells assembled with SNP-PC@MPC@CoSe-modified separator enable superb long-cycle stability and satisfactory rate performance.An excellent rate capacity of 796 mAh g^(−1)at a high current rate of 4 C with an ultra-low capacity fading of 0.06%over 700 cycles can be acquired.More impressively,even in a harsh test condition of 5.65 mg cm^(−2)sulfur loading and 4μL mg^(−1)ratio of electrolyte to active materials,the battery can still display a specific capacity of 980 mAh g^(−1)(area capacity of∼5.54 mAh cm^(−2))at 0.1 C.This work provides a promising route toward high-performance Li-S batteries.

关键词： Lithium-sulfur battery Biomass conversion S,N,P-codoped porous carbon CoSe modulation Multifunctional separator Synergism of strong and weak polarity

Functional Fibers and Functional Fiber‑Based Components for High‑Power Lasers

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Advanced Fiber Materials 2023年第1期5卷 59-106页

作者： xiao Chen Tianfu Yao Liangjin Huang Yi An Hanshuo Wu zhiyong Pan Pu Zhou College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China

The success of high-power fiber lasers is fueled by maturation of active and passive fibers,combined with the availability of high-power fiber-based components.In this contribution,we first overview the enormous potential of rare-earth doped fibers in spectral coverage and recent developments of key fiber-based components employed in high-power laser systems.Subsequently,the emerging functional active and passive fibers in recent years,which exhibit tremendous advantages in balancing or mitigating parasitic nonlinearities hindering high-power transmission,are outlined from the perspectives of geo-metric and material engineering.Finally,novel functional applications of conventional fiber-based components for nonlinear suppression or spatial mode selection,and correspondingly,the high-power progress of function fiber-based components in power handling are introduced,which suggest more flexible controllability on high-power laser operations.

关键词： High-power laser Laser fiber Passive fiber-based component Functional fiber Functional fiber-based component