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Hetero Nucleus Growth Stabilizing Zinc Anode for High‑Biosecurity Zinc‑Ion Batteries 被引量:6
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作者 Jingjing Li Zhexuan Liu +6 位作者 Shaohua Han Peng Zhou Bingan Lu Jianda Zhou Zhiyuan Zeng Zhizhao Chen Jiang Zhou 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第12期349-360,共12页
Biocompatible devices are widely employed in modernized lives and medical fields in the forms of wearable and implantable devices,raising higher requirements on the battery biocompatibility,high safety,low cost,and ex... Biocompatible devices are widely employed in modernized lives and medical fields in the forms of wearable and implantable devices,raising higher requirements on the battery biocompatibility,high safety,low cost,and excellent electrochemical performance,which become the evaluation criteria toward developing feasible biocompatible batteries.Herein,through conducting the battery implantation tests and leakage scene simulations on New Zealand rabbits,zinc sulfate electrolyte is proved to exhibit higher biosecurity and turns out to be one of the ideal zinc salts for biocompatible zinc-ion batteries(ZIBs).Furthermore,in order to mitigate the notorious dendrite growth and hydrogen evolution in mildly acidic electrolyte as well as improve their operating stability,Sn hetero nucleus is introduced to stabilize the zinc anode,which not only facilitates the planar zinc deposition,but also contributes to higher hydrogen evolution overpotential.Finally,a long lifetime of 1500 h for the symmetrical cell,the specific capacity of 150 mAh g^(-1)under 0.5 A g^(-1)for the Zn-MnO_(2)battery and 212 mAh g^(-1)under 5 A g^(-1)for the Zn—NH4V4O10 battery are obtained.This work may provide unique perspectives on biocompatible ZIBs toward the biosecurity of their cell components. 展开更多
关键词 Aqueous zinc-ion batteries Biocompatible devices Operating stability Zinc anode Zinc salts electrolyte
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Enhancement of Frster energy transfer from thermally activated delayed fluorophores layer to ultrathin phosphor layer for high color stability in non-doped hybrid white organic light-emitting devices 被引量:1
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作者 王子君 赵娟 +2 位作者 周畅 祁一歌 于军胜 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第4期404-410,共7页
Fluorescence/phosphorescence hybrid white organic light-emitting devices(WOLEDs) based on double emitting layers(EMLs) with high color stability are fabricated.The simplified EMLs consist of a non-doped blue therm... Fluorescence/phosphorescence hybrid white organic light-emitting devices(WOLEDs) based on double emitting layers(EMLs) with high color stability are fabricated.The simplified EMLs consist of a non-doped blue thermally activated delayed fluorescence(TADF) layer using 9,9-dimethyl-9,10-dihydroacridine-diphenylsulfone(DMAC-DPS) and an ultrathin non-doped yellow phosphorescence layer employing bis[2-(4-tertbutylphenyl)benzothiazolato-N,C2']iridium(acetylacetonate)((tbt)_2Ir(acac)).Two kinds of materials of 4,7-diphenyl-1,10-phenanthroline(Bphen) and 1,3,5-tris(2-Nphenylbenzimidazolyl) benzene(TPBi) are selected as the electron transporting layer(ETL),and the thickness of yellow EML is adjusted to optimize device performance.The device based on a 0.3-nm-thick yellow EML and Bphen exhibits high color stability with a slight Commission International de l'Eclairage(CIE) coordinates variation of(0.017,0.009) at a luminance ranging from 52 cd/m^2 to 6998 cd/m^2.The TPBi-based device yields a high efficiency with a maximum external quantum efficiency(EQE),current efficiency,and power efficiency of 10%,21.1 cd/A,and 21.3 lm/W,respectively.The ultrathin yellow EML suppresses hole trapping and short-radius Dexter energy transfer,so that Forster energy transfer(FRET)from DMAC-DPS to(tbt)_2Ir(acac) is dominant,which is beneficial to keep the color stable.The employment of TPBi with higher triplet excited state effectively alleviates the triplet exciton quenching by ETL to improve device efficiency. 展开更多
关键词 white organic light-emitting devices non-doped emitting layers thermally activated delayed fluo-rescence color stability
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Stability Test of Ampicillin Sodium Solutions in the Accufuser^(■) Elastomeric Infusion Device Using HPLC-UV Method 被引量:2
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作者 Min-A.Kang Ju-Seop Kang 《Pharmacology & Pharmacy》 2012年第4期462-467,共6页
The stabilities of two kinds of solutions (30 mg/mL) of Ampicillin sodium in 0.9% NaCl in water (NS, normal saline) and in sterile water (SW) in the intravenous elastomeric infusion device (Accufuser&#174) were ev... The stabilities of two kinds of solutions (30 mg/mL) of Ampicillin sodium in 0.9% NaCl in water (NS, normal saline) and in sterile water (SW) in the intravenous elastomeric infusion device (Accufuser&#174) were evaluated based on recommended solutions and storage periods. The injectable NS- and SW-Ampicillin solutions in the Accufuser&#174 device were stored and evaluated at controlled temperature (room temperature, 25℃ ± 2℃ and cold temperature, 4℃ ± 2℃) during 7 days. Effects of the periods of storage (from 0 to 7 days) and the temperatures of storage (RT and CT) on the physico-chemical appearances and concentrations of active compounds were determined. The visual clarity, pH, and concentrations of Ampicillin were determined by stability-indicating high-performance liquid chromatography (HPLC)-ultraviolet (UV) detection. The results showed that the amount of Ampicillin in studied solutions gradually decreased with time. The Ampicillin in NS, which was stored in CT, was relatively stable, retaining 94% of its original amount up to 7 days. The solution that showed least stability was Ampicillin in SW, which was stored in RT, retaining 80% of its original amount. Generally, solutions that were stored in CT were more stable than the solutions that were stored in RT. No significant changes in physical appearance or color of the solutions were observed during the study. Particles were not detected in any solution samples. In summary, two kinds of solutions of Ampicillin sodium, in NS and SW, showed different chemical stabilities with time in intravenous infusion device without any significant physical changes and retained about 94% vs 89% and 83% vs 80% of initial concentrations after 7 days in CT and RT, respectively. We suggest that 30 mg/mL of Ampicillin sodium in NS solution in an Accufuser&#174 infusion device which is stored in CT can be applicable for 7 days in clinical situations. 展开更多
关键词 Ampicillin Sodium Intravenous Elastomeric Infusion device(Accufuser^(■)) HPLC-UV Method Solution stability
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Performance and stability-enhanced inorganic perovskite light-emitting devices by employing triton X-100
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作者 Ao Chen Peng Wang +4 位作者 Tao Lin Ran Liu Bo Liu Quan-Jun Li Bing-Bing Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第4期629-632,共4页
Significantly enhanced electroluminescence performance and stability of all-inorganic perovskite light-emitting devices(PeLEDs) have been achieved by adding triton X-100 into the perovskite precursors.The small perovs... Significantly enhanced electroluminescence performance and stability of all-inorganic perovskite light-emitting devices(PeLEDs) have been achieved by adding triton X-100 into the perovskite precursors.The small perovskite grains arranged tightly and formed large grains as the triton X-100 were introduced.Thus the nonradiative defects originated from Pb atoms at the grain boundaries were highly passivated by triton X-100 and resulted in the promotion of PeLED performance,including a turn-on voltage of 3.2 V,a brightness of 63500 cd/m^(2),a current efficiency of 17.4 cd/A,and a prolonged lifetime of 2 h in air. 展开更多
关键词 electroluminescence performance stabilITY perovskite light-emitting devices(Pe LEDs) triton X-100
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Stability of Nafcillin Sodium Solutions in the Accufuser^(■) Elastomeric Infusion Device
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作者 Min-A Kang Ju-Seop Kang 《Pharmacology & Pharmacy》 2013年第1期57-62,共6页
The aim of this study was to investigate the stabilities of two kinds of solutions of nafcillin sodium (2.5 mg/mL) in 0.9% sodium chloride solution (NS, normal saline) and in injectable 5% dextrose water (D5W) in the ... The aim of this study was to investigate the stabilities of two kinds of solutions of nafcillin sodium (2.5 mg/mL) in 0.9% sodium chloride solution (NS, normal saline) and in injectable 5% dextrose water (D5W) in the intravenous elastomeric infusion device (Accufuser&#174) based on recommended solutions and storage periods. The injectable nafcillin solutions (NS- and D5W-nafcillin) in the Accufuser&#174?device were stored and evaluated at controlled temperatures (room temperature, RT, 5℃ ± 2℃ and cold temperature, CT, 4℃ ± 2℃) during 6 weeks. Effects of the periods of storage (from 0 to 6 weeks) and the temperatures of storage (RT and CT) on the physicochemical appearances and concentrations of active compounds were determined. The visual clarity, pH, and concentrations of nafcillin sodium were determined by stability-indicating high-performance liquid chromatography (HPLC)-ultraviolet (UV) detection. The results showed that in NS and D5W solutions, the amount of nafcillin slightly changed and remained 92.66% and 97.30% of their initial amounts at CT during 6 weeks, respectively. On the other hand, in NS and D5W solutions at RT, the amount significantly decreased with time and reached 27.66% and 31.97% of their initial amounts during 4 weeks, respectively. Slight decrement of pH was observed in CT storage while significant change was observed in the RT storage. Moreover, in CT, no significant changes in physical appearances and colors of the solutions were observed during the study. However, the solutions changed into yellowish color and some particles were detected in both kinds of nafcillin solutions (NS and D5W) after 1.5 weeks in RT conditions. To sum up, under CT two kinds of nafcillin sodium solutions (NS and D5W) were stable with time in Accufuser&#174?without any significant physical changes and retained almost all of the initial concentrations up to 6 weeks. However, the solutions were not stable in RT storage. We suggest that nafcillin sodium solutions in an Accufuser&#174?should be preferentially diluted in NS and D5W while storing in CT condition. 展开更多
关键词 stabilITY Nafcillin Sodium Intravenous Elastomeric Infusion device(Accufuser^(■))
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Complementary multicolor electrochromic devices with excellent stability based on porous tin oxide nanosheet scaffold
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作者 Chenchen Bian Jinhui Wang +6 位作者 Huanhuan Liu Yin Yan Ping Zhang Weilong Yang Sensen Jia Xiaodan Guo Guofa Cai 《Nano Research》 SCIE EI CSCD 2024年第4期3035-3042,共8页
Electrochromic devices(ECDs)have been extensively investigated as promising candidates in broad cutting-edge applications,such as smart windows,electronic labels,adaptive camouflage,etc.However,they have suffered from... Electrochromic devices(ECDs)have been extensively investigated as promising candidates in broad cutting-edge applications,such as smart windows,electronic labels,adaptive camouflage,etc.However,they have suffered from either inadequate color variations or poor cycling stability for a long time.Herein,we developed a general strategy to boost the cyclic stability and enrich the color variations of ECDs by scrupulous design of the composition and nanostructure of electrodes,in which porous tin oxide(SnO_(2))nanosheets serve as the scaffold and typical metal oxides or conducting polymers as the active electrochromic materials.Various electrochromic composite materials,including polyaniline(PANI)@SnO_(2),V2O5@SnO_(2),and WO_(3)@SnO_(2) heterostructured nanoarrays were prepared by the facile wet-chemical method.These composite electrodes exhibit remarkable electrochromic performances,e.g.,superior cycling stability(more than 2000 cycles),rich color variations(more than 5 colors for PANI@SnO_(2)),and enlarged optical modulation.These excellent performances account for the heterogenous porous nanoarrays,which not only facilitate the intercalation/extraction of ions but also relieve the stress generated during the electrochemical process.In addition,diverse prototypes of complementary multicolor ECD with excellent cycling stability(over thousands of cycles)and rich color variations(8 colors)were realized for the first time.We believe that our work put forward a general strategy for developing high-quality multicolor complementary electrochromic devices. 展开更多
关键词 ELECTROCHROMISM tin oxide metal oxide cycling stability multicolor complementary device
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Emerging CoMn-LDH@MnO2 electrode materials assembled using nanosheets for flexible and foldable energy storage devices 被引量:10
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作者 Yue Zhao Jiafeng He +3 位作者 Meizhen Dai Depeng Zhao Xiang Wu Baodan Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第6期67-73,I0003,共8页
CoMn layered double hydroxides(CoMn-LDH)are promising electrode materials for supercapacitors because of their excellent cyclic stability.However,they possess relatively low capacitances.In this work,hybrid CoMn-LDH@M... CoMn layered double hydroxides(CoMn-LDH)are promising electrode materials for supercapacitors because of their excellent cyclic stability.However,they possess relatively low capacitances.In this work,hybrid CoMn-LDH@MnO2 products grown on Ni foams were obtained through a facile hydrothermal method.The as-synthesized samples employed as electrodes deliver a specific capacitance of 2325.01 F g^-1 at 1 A g^-1.An assembled asymmetric supercapacitor using these products as positive electrodes shows a maximum energy density of 59.73 W h kg^-1 at 1000.09 W kg^-1.The prominent electrochemical performance of the as-prepared electrodes could be attributes to hierarchical structures.These findings suggest that hybrid structures might be potential alternatives for future flexible energy storage devices. 展开更多
关键词 CoMn-LDH@MnO2 electrode Specific capacitance FLEXIBLE device Cyclic stability
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Air-Stable Ultrabright Inverted Organic Light-Emitting Devices with Metal Ion-Chelated Polymer Injection Layer 被引量:4
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作者 Shihao Liu Chunxiu Zang +6 位作者 Jiaming Zhang Shuang Tian Yan Wu Dong Shen Letian Zhang Wenfa Xie Chun-Sing Lee 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第1期239-249,共11页
Here,this work presents an air-stable ultrabright inverted organic lightemitting device(OLED)by using zinc ionchelated polyethylenimine(PEI)as electron injection layer.The zinc chelation is demonstrated to increase th... Here,this work presents an air-stable ultrabright inverted organic lightemitting device(OLED)by using zinc ionchelated polyethylenimine(PEI)as electron injection layer.The zinc chelation is demonstrated to increase the conductivity of the PEI by three orders of magnitude and passivate the polar amine groups.With these physicochemical properties,the inverted OLED shows a record-high external quantum efficiency of 10.0% at a high brightness of 45,610 cd m^(-2) and can deliver a maximum brightness of 121,865 cd m^(-2).Besides,the inverted OLED is also demonstrated to possess an excellent air stability(humidity,35%)with a half-brightness operating time of 541 h@1000 cd m^(-2) without any protection nor encapsulation. 展开更多
关键词 Air stability Ultrabright Electron injection Metal ion chelation Inverted organic light-emitting device
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A simple encapsulation method for organic optoelectronic devices
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作者 孙倩倩 安桥石 张福俊 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期322-326,共5页
The performances of organic optoelectronic devices, such as organic light emitting diodes and polymer solar cells, have rapidly improved in the past decade. The stability of an organic optoelectronic device has become... The performances of organic optoelectronic devices, such as organic light emitting diodes and polymer solar cells, have rapidly improved in the past decade. The stability of an organic optoelectronic device has become a key problem for further development. In this paper, we report one simple encapsulation method for organic optoelectronic devices with a parafilm, based on ternary polymer solar cells (PSCs). The power conversion efficiencies (PCE) of PSCs with and without encapsulation decrease from 2.93% to 2.17% and from 2.87% to 1.16% after 168-hours of degradation under an ambient environment, respectively. The stability of PSCs could be enhanced by encapsulation with a parafilm. The encapsulation method is a competitive choice for organic optoelectronic devices, owing to its low cost and compatibility with flexible devices. 展开更多
关键词 organic optoelectronic devices stabilITY ENCAPSULATION
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Review on Chemical Stability of Lead Halide Perovskite Solar Cells 被引量:1
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作者 Jing Zhuang Jizheng Wang Feng Yan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第6期220-253,共34页
Lead halide perovskite solar cells(PSCs) have become a promising next-generation photovoltaic technology due to their skyrocketed power conversion efficiency. However, the device stability issues may restrict their co... Lead halide perovskite solar cells(PSCs) have become a promising next-generation photovoltaic technology due to their skyrocketed power conversion efficiency. However, the device stability issues may restrict their commercial applications, which are dominated by various chemical reactions of perovskite layers. Hence, a comprehensive illustration on the stability of perovskite films in PSCs is urgently needed. In this review article, chemical reactions of perovskite films under different environmental conditions(e.g., moisture,oxygen, light) and with charge transfer materials and metal electrodes are systematically elucidated. Effective strategies for suppressing the degradation reactions of perovskites, such as buffer layer introduction and additives engineering,are specified. Finally, conclusions and outlooks for this field are proposed. The comprehensive review will provide a guideline on the material engineering and device design for PSCs. 展开更多
关键词 Perovskite solar cells Chemical reactions DEFECTS Degradation device stability
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All-Polymer Solar Cells and Photodetectors with Improved Stability Enabled by Terpolymers Containing Antioxidant Side Chains 被引量:1
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作者 Chunyang Zhang Ao Song +7 位作者 Qiri Huang Yunhao Cao Zuiyi Zhong Youcai Liang Kai Zhang Chunchen Liu Fei Huang Yong Cao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第9期190-204,共15页
It is of vital importance to improve the long-term and photostability of organic photovoltaics,including organic solar cells(OSCs)and organic photodetectors(OPDs),for their ultimate industrialization.Herein,two series... It is of vital importance to improve the long-term and photostability of organic photovoltaics,including organic solar cells(OSCs)and organic photodetectors(OPDs),for their ultimate industrialization.Herein,two series of terpolymers featuring with an antioxidant butylated hydroxytoluene(BHT)-terminated side chain,PTzBI-EHp-BTBHTx and N2200-BTBHTx(x=0.05,0.1,0.2),are designed and synthesized.It was found that incorporating appropriate ratio of benzothiadiazole(BT)with BHT side chains on the conjugated backbone would induce negligible effect on the molecular weight,absorption spectra and energy levels of polymers,however,which would obviously enhance the photostability of these polymers.Consequently,all-polymer solar cells(all-PSCs)and photodetectors were fabricated,and the all-PSC based on PTzBI-EHp-BTBHT0.05:N2200 realized an optimal power conversion efficiency(PCE)approaching~10%,outperforming the device based on pristine PTzBI-EHp:N2200.Impressively,the all-PSCs based on BHT-featuring terpolymers displayed alleviated PCEs degradation under continuous irradiation for 300 h due to the improved morphological and photostability of active layers.The OPDs based on BHT-featuring terpolymers achieved a lower dark current at−0.1 bias,which could be stabilized even after irradiation over 400 h.This study provides a feasible approach to develop terpolymers with antioxidant efficacy for improving the lifetime of OSCs and OPDs. 展开更多
关键词 Organic photovoltaics device operational stability All-polymer solar cell Organic photodetector ANTIOXIDANT
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交错凸齿式宽苗带小麦精量排种器设计与试验 被引量:1
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作者 张春岭 刘涛 +3 位作者 郑子浩 方俊 谢晓东 陈黎卿 《农业工程学报》 EI CAS CSCD 北大核心 2024年第5期47-59,共13页
针对外槽轮式小麦宽苗带排种器排量不稳定和苗带内种子分布均匀性较差的问题,该研究设计了一种交错凸齿式宽苗带小麦精量排种器。通过连续充种分析和排量计算,确定凸齿高度和凸齿角度是影响排量一致性和排种均匀性的关键参数。应用离散... 针对外槽轮式小麦宽苗带排种器排量不稳定和苗带内种子分布均匀性较差的问题,该研究设计了一种交错凸齿式宽苗带小麦精量排种器。通过连续充种分析和排量计算,确定凸齿高度和凸齿角度是影响排量一致性和排种均匀性的关键参数。应用离散元法对上述关键参数进行中心旋转组合仿真试验,结果表明,对排量一致性、排种均匀性影响显著性程度由大到小的因素分别依次为凸齿角、凸齿高、作业速度,且均具有交互影响。借助响应面分析,得出凸齿高5 mm、凸齿角75°时的排量一致性和排种均匀性较优,平均变异系数分别为2.27%和7.61%。对该参数组合排种器进行样机试制,并进行台架试验,台架试验结果表明,排种一致性和均匀性变异系数与仿真值误差均低于5%,说明仿真优化结果可靠、准确。田间对比试验结果表明,播量120、150和180 kg/hm~2时,交错凸齿式宽苗带小麦精量排种器的播量一致性、纵向播种均匀性和横向播种均匀性变异系数分别较外槽轮式排种器降低0.99、3.01和9.38个百分点,满足小麦宽苗带播种农艺要求。研究结果可为提高排种均匀性的小麦排种装置设计提供参考。 展开更多
关键词 排种器 离散元法 小麦 精量排种 交错凸齿 排量稳定性 排种均匀性
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2BP-2000型水稻育秧播种机分盘装置研制 被引量:1
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作者 谢方平 杨靖 +3 位作者 符志勇 刘大为 龚明 程乐根 《农业工程学报》 EI CAS CSCD 北大核心 2024年第3期26-36,共11页
针对现有育秧播种机分盘装置生产效率较低、高速作业时易出现卡盘和秧盘输送不连续等问题,该研究设计了一种生产效率不低于2000盘/h的机械气动式自动分盘装置,可快速、准确完成分盘和供盘,适配2BP-2000型水稻育秧播种机高速播种。阐述... 针对现有育秧播种机分盘装置生产效率较低、高速作业时易出现卡盘和秧盘输送不连续等问题,该研究设计了一种生产效率不低于2000盘/h的机械气动式自动分盘装置,可快速、准确完成分盘和供盘,适配2BP-2000型水稻育秧播种机高速播种。阐述了分盘装置的基本结构和工作原理,开展分盘、接盘过程分析,确定装置稳定分盘、接盘作业的关键机构与工作参数。分盘稳定性试验结果表明,生产率为1600~2000盘/h时,分盘稳定性不低于98.67%。开展以层叠秧盘数、生产率和秧盘质量为试验因素,以接盘成功率为试验指标的三因素三水平正交旋转组合试验,得到影响接盘成功率的因素主次关系为生产率、层叠秧盘数、秧盘质量,其中生产率、层叠秧盘数对接盘成功率影响显著(P<0.05),秧盘质量对接盘成功率影响不显著(P≥0.05),表明分盘装置对不同质量的秧盘适应性较好,其最优参数组合为:生产率2000盘/h、层叠秧盘数6盘/层、秧盘质量750 g/盘,该条件下分盘装置的接盘成功率均值为98.43%,与预测值仅相差0.29个百分点。研究结果对提高水稻硬盘育秧播种机械化水平具有实用价值。 展开更多
关键词 农业机械 试验 水稻育秧播种 分盘装置 分盘稳定性 接盘成功率
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MMC型柔性直流输电系统的中高频振荡无源阻尼抑制策略
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作者 聂永辉 张德伟 +2 位作者 高磊 吴春迎 张瑞东 《电力系统保护与控制》 EI CSCD 北大核心 2024年第16期141-149,共9页
较长的控制链路延时会导致基于模块化多电平换流器(modular multilevel converter,MMC)的柔性直流输电系统阻抗在高频段出现负阻尼区间,易与交流系统分布电容相互作用引发高频振荡。现有有源阻尼抑制策略虽可有效抑制高频振荡,但会恶化... 较长的控制链路延时会导致基于模块化多电平换流器(modular multilevel converter,MMC)的柔性直流输电系统阻抗在高频段出现负阻尼区间,易与交流系统分布电容相互作用引发高频振荡。现有有源阻尼抑制策略虽可有效抑制高频振荡,但会恶化中频段阻抗特性,增加中频振荡发生的风险。为有效抑制中高频振荡,提出在MMC交流侧母线处并联无源阻抗重塑装置的无源阻尼抑制策略。首先,推导出MMC简化模型并验证其准确性。其次,根据奈奎斯特稳定判据与最小功率损耗约束设计阻抗重塑装置参数,实现MMC系统阻抗重塑。最后,应用阻抗法对比分析重塑前后MMC系统阻抗特性,分析阻抗重塑装置对MMC系统阻抗的修正效果。在PSCAD/EMTDC中搭建含无源阻抗重塑装置的MMC电磁暂态仿真模型。仿真结果表明,该抑制策略在中高频段均可有效抑制MMC系统的振荡现象,对系统稳态特性影响小,且基频功率损耗低。 展开更多
关键词 柔性直流输电 MMC简化模型 中高频振荡 阻抗稳定分析 无源阻抗重塑装置
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植物茎秆柔性夹持装置刚柔耦合仿真与试验 被引量:2
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作者 韩明兴 李淼 +2 位作者 段宏兵 徐琨 余锴 《农业机械学报》 EI CAS CSCD 北大核心 2024年第2期109-118,共10页
针对现有植物茎秆夹持装置存在夹伤茎秆、夹持行程及夹持力不可调等问题,设计一种植物茎秆柔性夹持装置,夹持手内置弹簧可实现植物茎秆柔性夹持,能进行夹持力与夹持行程双调节,更好适应植物茎秆在力学试验、嫁接、茎秆切割试验等领域夹... 针对现有植物茎秆夹持装置存在夹伤茎秆、夹持行程及夹持力不可调等问题,设计一种植物茎秆柔性夹持装置,夹持手内置弹簧可实现植物茎秆柔性夹持,能进行夹持力与夹持行程双调节,更好适应植物茎秆在力学试验、嫁接、茎秆切割试验等领域夹持需求。基于所建立夹持装置刚柔耦合仿真模型,进行夹持力、夹持行程、弹簧刚度等多因素动力学对比仿真与试验分析,以弹簧刚度为设计变量进行灵敏度及稳定性分析,研究不同弹簧刚度对柔性夹持装置夹持性能的影响。仿真与试验结果表明:装置最大夹持直径为68.8 mm,基于所构建夹持装置精准夹持力模型,可平稳调控夹持行程、速度及夹持力;随着弹簧刚度的增加,夹持力逐渐变大,夹持稳定性增加,综合比较发现当弹簧刚度为10 N/mm时,可满足装置施加400 N切割力时植物茎秆稳定夹持需求,柔性夹持力波动较小,能有效避免损伤植物茎秆。 展开更多
关键词 植物茎秆 柔性夹持装置 稳定性分析 可调夹持力 刚柔耦合仿真 ADAMS
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基于FPGA和LoRa的燃烧室振动信号无线测试装置设计
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作者 王峥岩 洪应平 张会新 《仪表技术与传感器》 CSCD 北大核心 2024年第3期50-56,共7页
燃烧不稳定性问题可引起大幅的机械振动,严重影响发动机正常工作。为满足新型试验需求,针对传统燃烧室测试装置灵活性不足、可靠性差等问题,设计了一种基于FPGA和LoRa的燃烧室振动信号无线测试装置,以FPGA作为主控单元,将前端高速AD采... 燃烧不稳定性问题可引起大幅的机械振动,严重影响发动机正常工作。为满足新型试验需求,针对传统燃烧室测试装置灵活性不足、可靠性差等问题,设计了一种基于FPGA和LoRa的燃烧室振动信号无线测试装置,以FPGA作为主控单元,将前端高速AD采集的振动传感器数据存入Flash,通过LoRa技术并结合以太网的高速运行,在PC端进行远程操控和数据处理。试验表明:该装置可以实现至少500 m开阔距离内待测燃烧室振动信号的可靠测试,工作稳定,实时性强。 展开更多
关键词 燃烧稳定性 测试装置 LoRa FPGA 振动信号
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钙钛矿太阳能电池的稳定性因素及封装提升性能
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作者 戴加祺 章东 吴小山 《物理学进展》 北大核心 2024年第1期19-48,共30页
钙钛矿太阳能电池作为第三代新概念太阳能电池,具有光电转换效率高、成本低和加工灵活等优点,近年来发展迅速,虽然其光电转换效率逐渐可与硅电池相媲美,已接近工业应用水平,但钙钛矿太阳能电池工业应用核心问题是其稳定性。如何使钙钛... 钙钛矿太阳能电池作为第三代新概念太阳能电池,具有光电转换效率高、成本低和加工灵活等优点,近年来发展迅速,虽然其光电转换效率逐渐可与硅电池相媲美,已接近工业应用水平,但钙钛矿太阳能电池工业应用核心问题是其稳定性。如何使钙钛矿太阳能电池长期保持高效率是研究人员需要解决的最大问题。目前,封装作为解决钙钛矿太阳能电池外部稳定性问题的手段之一已经被广泛研究,良好的封装不仅可以解决器件的稳定性问题,还可以保证器件的安全性,延长使用寿命。本文简要介绍了影响钙钛矿太阳能电池稳定性的因素及稳定性测试的条件。最后介绍了钙钛矿太阳能电池的不同封装结构、封装工艺和封装材料对封装性能的影响。随着封装研究的不断深入,研究人员将不断优化和解决存在的问题,最终实现钙钛矿太阳能电池的大规模产业化应用。 展开更多
关键词 钙钛矿太阳能电池 设备稳定性 封装材料 工业化应用
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Te基热电器件反常界面层生长行为及界面稳定性研究
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作者 苗鑫 闫世强 +3 位作者 韦金豆 吴超 樊文浩 陈少平 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2024年第8期903-910,I0004-I0007,共12页
单质Te具有优异的热电优值(ZT),但其与金属电极连接界面处的剧烈元素交互扩散及反应会引入较大的接触电阻率(ρc),导致器件的转换效率(η)较低。因此,寻找合适的阻挡层来优化Te与金属电极间的连接至关重要。本研究基于梯度结构报道了一... 单质Te具有优异的热电优值(ZT),但其与金属电极连接界面处的剧烈元素交互扩散及反应会引入较大的接触电阻率(ρc),导致器件的转换效率(η)较低。因此,寻找合适的阻挡层来优化Te与金属电极间的连接至关重要。本研究基于梯度结构报道了一种宽相场Ni-Te合金阻挡层NiTe_(2-m)(NixTe(x=0.500~0.908))。结果表明,当x=0.500时,Ni_(0.5)Te/Te_(0.985)Sb_(0.015)/Ni_(0.5)Te器件的界面处无任何反应层及微观缺陷,ρ_(c)小于10μΩ·cm^(2),η在180K温差(热端温度473K)时达到了理论值的75%。同时,界面具有良好的热稳定性,在473K老化期间,界面微观组织、ρ_(c)以及η无明显变化。当x>0.500时,界面反应层厚度随x增大而逐渐减小,即主导界面反应层生长行为的因素并非常规的界面反应能及浓度梯度等热力学因素。进一步分析表明,反常生长源于动力学因素中的“原子空位”对反应层生成的迟滞作用。 展开更多
关键词 TE 热电器件 扩散动力学 阻挡层 热稳定性
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复合扰动模型的无人机自动配平装置结构设计
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作者 石冬剑 李姗姗 +1 位作者 曹将栋 张华 《机械设计与制造》 北大核心 2024年第10期369-374,共6页
无人机平台加装作业设备的作动及飞行环境的干扰均会造成无人机重心的偏移,影响作业精度。提出一种复合扰动模型的自动配平装置稳定无人机姿态的方法,考虑气流扰动、无人机载荷变化等因素,进行了无人机俯仰角、滚转角、偏航角多目标的... 无人机平台加装作业设备的作动及飞行环境的干扰均会造成无人机重心的偏移,影响作业精度。提出一种复合扰动模型的自动配平装置稳定无人机姿态的方法,考虑气流扰动、无人机载荷变化等因素,进行了无人机俯仰角、滚转角、偏航角多目标的自动配平装置结构优化设计并对无人机稳定性展开试验验证。结果表明,与多旋翼无人机加装配平装置前相比,无人机俯仰角、滚转角、偏航角超调量分别减小11.6%、48.5%、34.5%,对应的姿态稳定时间分别缩短0.06s、0.07s、0.06s,无人机三轴方向的控制稳定度分别提高54.4%、69.5%、60.8%,解决了气流扰动及无人机载荷变化复合作用影响无人机飞行姿态波动的问题,确保了飞行的稳定性。这里提出方法可为复杂工况条件下展开作业的多旋翼无人机结构优化设计提供参考。 展开更多
关键词 多旋翼无人机 复合扰动模型 自动配平装置 稳定性
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扣件失效对动力稳定装置-轨道系统动态响应的影响
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作者 褚阳 王立华 +3 位作者 唐浩 陈太茂 黄洪燚 赵泽民 《中国工程机械学报》 北大核心 2024年第4期545-550,共6页
为研究扣件失效对动力稳定作业下轨枕动态响应的影响,基于多体系统动力学理论建立稳定装置-轨道刚柔耦合系统动力学仿真模型,搭建试验平台验证仿真模型的合理性。通过改变稳定装置的激振频率和垂直下压力,研究不同作业工况和扣件服役状... 为研究扣件失效对动力稳定作业下轨枕动态响应的影响,基于多体系统动力学理论建立稳定装置-轨道刚柔耦合系统动力学仿真模型,搭建试验平台验证仿真模型的合理性。通过改变稳定装置的激振频率和垂直下压力,研究不同作业工况和扣件服役状态下轨枕的动力学响应特性。结果表明:激振频率和下压力对扣件正常服役下的轨枕横向位移和加速度影响较大,对扣件失效下轨枕的动态响应影响较小;扣件失效数量越多,系统总能量传递效率越低,扣件失效数量为1和2时,系统总能量传递效率比扣件正常服役时低21.11%和31.19%。 展开更多
关键词 动力稳定装置 扣件失效 能量传递 动态响应
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