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Advancing oxygen separation:insights from experimental and computational analysis of La_(0.7)ca.(0.3)Co_(0.3)Fe_(0.6)M_(0.1)O_(3-δ)(M=Cu,Zn)oxygen transport membranes

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Frontiers of Chemica. Science and Engineering 2024年第6期18卷 17-29页

作者： Guoxing Chen Wenmei Liu Marc Widenmeyer Xiao Yu zhijun Zhao Songhak Yoon Ruijuan Yan Wenjie Xie Armin Feldhoff Gert Homm Emanuel Ionescu Maria Fyta Anke Weidenkaff Fraunhofer Research Institution for Materials Recycling and Resource Strategies IWKS Alzenau 63755Germany Electrochemistry Laboratory Paul Scherrer InstituteVilligen PSI 5232Switzerland Department of Materials and Earth Sciences Materials and ResourcesTechnical University of DarmstadtDarmstadt 64287Germany Institute of Physica. Chemistry and Electrochemistry Leibniz University HannoverHannover 30167Germany Institute for Computational Physics University of StuttgartStuttgart 70569Germany Computational Biotechnology RWTH AachenAachen 52074Germany

In this study,perovskite-type La_(0.7)ca.(0.3)Co_(0.3)Fe_(0.6)M_(0.1)O_(3-δ)(M=Cu,Zn)powders were synthesized using a sca.able reverse co-precipitation method,presenting them as novel materials for oxygen transport *** comprehensive study covered various aspects including oxygen permeability,crystal structure,conductivity,morphology,CO_(2) tolerance,and long-term regenerative durability with a focus on phase structure and *** membrane La_(0.7)ca.(0.3)Co_(0.3)Fe_(0.6)M_(0.1)O_(3-δ)exhibited high oxygen permeation fluxes,reaching up to 0.88 and 0.64 mL·min^(−1)·cm^(−2) under air/He and air/CO_(2) gradients at 1173 K,*** 1600 h of CO_(2) exposure,the perovskite structure remained intact,showca.ing superior CO_(2) resistance.A combination of first principles simulations and experimental measurements was employed to deepen the understanding of Cu/Zn substitution effects on the structure,oxygen vaca.cy formation,and transport behavior of the *** findings underscore the potential of this highly CO_(2)-tolerant membrane for applica.ions in high-temperature oxygen *** enhanced insights into the oxygen transport mechanism contribute to the advancement of next-generation membrane materials.

关键词： perovskite oxygen permeation membrane oxygennionsdiffusiono xygen vaca.cy formation energy energy barrier

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Properties of Self-recoverable Mechanoluminescence Phosphor ca.(5)Ga_(6)O_(14)∶Eu^(3+) and Its Information Encryption Applica.ion

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发光学报 2024年第9期45卷 1445-1455页

作者： ZHANG Ting WANG zhijun WANG Dawei ZHAO Jinxin YANG Zhiping LI Panlai Hebei Key Laboratory of Optic-electronic Information and Materials College of Physics Science&TechnologyHebei UniversityBaoding 071002China Hebei Key Laboratory of Semiconductor Lighting and Display Critica. Materials Hebei Ledphor Optoelectronics Technology Co.LTD.Baoding 071000China

A novel self-recoverable mechanoluminescent phosphor ca.(5)Ga_(6)O_(14)∶Eu^(3+) was developed by the high-tem-perature solid-state reaction method,and its luminescence properties were ***_(5)Ga_(6)O_(14)∶Eu^(3+)ca. produce red mechanoluminescence,and importantly,it shows good *** mechanoluminescence of ca.(5)Ga_(6)O_(14)∶Eu^(3+) results from the piezoelectric field generated inside the material under stress,rather than the charge ca.riers stored in the traps,which ca. be confirmed by the multiple cycles of mechanoluminescence tests and heat treatment *** mechanoluminescence color ca. be turned from red to green by co-doping varied concentrations of Tb^(3+),which may be meaningful for encrypted letter *** encryption scheme for secure communica.ion was devised by harnessing mechanoluminescence patterns in diverse shapes and ASCII codes,which shows good encryption *** results suggest that the mechanoluminescence phosphor ca.(5)Ga_(6)O_(14)∶Eu^(3+),Tb^(3+)may be applied to the optica. information encryption.

关键词： phosphor mechanoluminescence self-recoverable information encryption

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鞣花酸余辉气凝胶制备及光物理性质研究

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林业工程学报 2024年第2期9卷 92-100页

作者：王瑞陈志俊李淑君东北林业大学材料科学与工程学院哈尔滨150040

以鞣花酸(EA)为发色团,将其掺杂在海藻酸钠(SA)中,经过与Zn2+、ca.+等二价金属离子交联凝胶化,凝胶经过冷冻干燥得到绿色余辉气凝胶(EA@SA)。对EA@SA气凝胶进行光物理性能分析,结果显示,使用不同的二价金属阳离子交联的气凝胶均有良好... 详细信息

以鞣花酸(EA)为发色团,将其掺杂在海藻酸钠(SA)中,经过与Zn2+、ca.+等二价金属离子交联凝胶化,凝胶经过冷冻干燥得到绿色余辉气凝胶(EA@SA)。对EA@SA气凝胶进行光物理性能分析,结果显示,使用不同的二价金属阳离子交联的气凝胶均有良好的磷光发射,EA@SA-Zn、EA@SA-ca.EA@SA-Sr、EA@SA-Ba气凝胶磷光寿命分别为275.71,157.59,123.92和144.56 ms,其中EA@SA-Zn气凝胶的磷光寿命最长。测试的荧光光谱及荧光寿命表明,EA@SA-Zn气凝胶的荧光发射以430 nm为发射中心,荧光寿命达到5.87 ns。SEM测试结果表明,制备的EA@SA-Zn气凝胶内部呈现网状多孔结构并且结构较为疏松,丰富的孔隙结构为EA分子提供良好的基质环境。同时,EA@SA-Zn气凝胶的元素映射图显示其表面均匀分布C、O、Zn、Cl 4种元素,这说明Zn2+与海藻酸钠交联充分,从而成功制备EA@SA-Zn气凝胶。将制备的EA@SA-Zn气凝胶放置在不同湿度环境下,随着相对湿度的增加,磷光寿命有所降低,干燥之后磷光寿命得到恢复;并且EA@SA-Zn气凝胶在乙腈(ACN)、乙醇(EtOH)、四氢呋喃(THF)、二氯甲烷(DCM)有机溶剂中均表现出良好的磷光发射,磷光寿命分别为254.76,260.14,266.64和268.67 ms。制备的EA@SA-Zn气凝胶在30 d后仍能观察到绿色余辉发射,具有磷光稳定性。最后,制备负载EA@SA-Zn气凝胶的余辉线,将其应用在刺绣和防伪领域,拓展了天然多酚制备余辉材料的策略及应用领域。

关键词：鞣花酸海藻酸钠气凝胶二价金属离子室温磷光

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液压泵和滚动轴承多种样本量的改进多任务故障诊断

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振动与冲击 2024年第4期43卷 270-278页

作者：郑直曾魁魁何玉灵李克王志军华北理工大学机械工程学院河北唐山063210 华北电力大学电机健康维护与故障预防河北省重点实验室河北保定071000

基于充足样本的多个设备元件导致多任务学习网络规模庞大,轻微和严重的跨元件零样本问题难度大。在多种样本量(充足样本和零样本)下,针对基于充足故障样本的多元件诊断网络规模过于庞大问题,引入MicroNet方法对多任务学习网络进行轻量... 详细信息

基于充足样本的多个设备元件导致多任务学习网络规模庞大,轻微和严重的跨元件零样本问题难度大。在多种样本量(充足样本和零样本)下,针对基于充足故障样本的多元件诊断网络规模过于庞大问题,引入MicroNet方法对多任务学习网络进行轻量化处理,然后利用热重启余弦退火算法优化上述网络,提出一种多任务轻量化学习网络模型,改善多任务学习网络的准确率和效率。针对更高难度的跨元件零样本问题,引入元学习方法进一步改进上述MT-MN-ca.进而提出一种改进多任务轻量化学习网络模型,解决轻微和严重的跨元件零样本问题。通过实测液压泵和滚动轴承故障验证所提两个网络模型的有效性和优越性,试验结果表明所提网络具有很高的实时性和准确率。

关键词：多任务学习轻量化元学习零样本故障诊断

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不同肥料配比对糜子产量和品质的调控效应

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西北农业学报 2024年第1期33卷 48-58页

作者：王君杰陈凌田翔乔治军山西农业大学农业基因资源研究中心/农业部黄土高原作物基因资源与种质创制重点实验室/杂粮种质资源发掘与遗传改良山西省重点实验室太原030031

为探明不同施肥方式对糜子营养品质、食味品质和产量的影响,于2019年在山西河曲进行试验,以河曲大红糜子为材料,选用不同配比的有机肥(羊粪)、生物菌肥、尿素和复合肥,研究不同施肥配比对糜子品质和产量的影响。结果表明:不同肥料配比... 详细信息

为探明不同施肥方式对糜子营养品质、食味品质和产量的影响,于2019年在山西河曲进行试验,以河曲大红糜子为材料,选用不同配比的有机肥(羊粪)、生物菌肥、尿素和复合肥,研究不同施肥配比对糜子品质和产量的影响。结果表明:不同肥料配比对糜子产量和品质性状显著影响,复合肥和有机肥(F+Y)配施显著提高糜子籽粒产量(GY)、净光合速率(Pn)、钙(ca.和铁(Fe)含量,显著减低直链淀粉含量(AC);相关性分析发现,籽粒产量(GY)和净光合速率(Pn)呈极显著正相关,相关系数为0.82,镁(Mg)与铁(Fe)呈极显著正相关,值为0.68,直链淀粉含量(AC)与醇溶蛋白含量(Gli)、钙(ca.达到极显著负相关,值分别为-0.66和-0.50;主成分分析发现,糜子各性状指标分为4个主成分,分别代表糜子食味品质、营养品质、产量指标和蛋白营养品质,综合得分以复合肥和有机肥(F+Y)处理最高,并显著高于其他处理。综上所述,复合肥(187.5 kg·hm^(-2))与有机肥(1.5×10^(4)kg·hm^(-2))配施是糜子获得优质高产的主要施肥方式。

关键词：糜子产量营养品质食味品质施肥方式

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新型应力发光材料ca.(5)Ga_(6)O_(14):Sm^(3+)制备及其性能

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发光学报 2024年第6期45卷 959-969页

作者：王强刘伟杜玉松李欢张志军饶光辉程帅赵景泰桂林电子科技大学材料科学与工程学院广西桂林541004 桂林电子科技大学广西信息材料重点实验室广西桂林541004 桂林电子科技大学机电工程学院广西桂林541004

采用高温固相法成功制备出新型ca.(5-x)Ga_(6)O_(14):xSm^(3+)应力发光材料。通过X射线衍射、扫描电镜、漫发射光谱、光致激发和发射光谱、荧光衰减曲线、应力发光光谱和热释光光谱等测试详细研究了ca.(5-x)Ga_(6)O_(14):xSm^(3+)的晶... 详细信息

采用高温固相法成功制备出新型ca.(5-x)Ga_(6)O_(14):xSm^(3+)应力发光材料。通过X射线衍射、扫描电镜、漫发射光谱、光致激发和发射光谱、荧光衰减曲线、应力发光光谱和热释光光谱等测试详细研究了ca.(5-x)Ga_(6)O_(14):xSm^(3+)的晶体结构、表面形貌、光致发光和应力发光性能及其发光机理。在404 nm激发下,ca.(5-x)Ga_(6)O_(14):xSm^(3+)呈现出4个发射峰,分别位于562,599,642,715 nm,对应Sm^(3+)的^(4)G_(5/2)→6Hj(j=5/2,7/2,9/2,11/2)的特征发射。随着Sm^(3+)离子掺杂浓度的增加,发光强度先增强后减弱,在x=0.07时获得最强发射,且衰减时间从1.92 ms缩短至1.30 ms。在滑动摩擦激发下可获得ca.(5-x)Ga_(6)O_(14):xSm^(3+)的应力发光发射带,且应力发光强度与施加应力满足线性增长,表明该材料在应力传感领域具有潜在应用价值。

关键词：应力发光 ca.(5)Ga_(6)O_(14) Sm^(3+)

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Chemica. compositions of precipitation and sca.enging of particles in Beijing

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Science China Chemistry 2005年第3期48卷 265-272页

作者： HU Min ZHANG Jing WU zhijun State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences Peking University Beijing 100871 China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences Peking University Beijing 100871 China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences Peking University Beijing 100871 China

Totally 23 precipitation samples were collected in Beijing from May to November in 2003. In order to investigate the chemica. composition of precipitation samples, pH, conductivity, concentrations of water-soluble ions and organic acids were analyzed. The average pH of pre-cipitations is 6.18, belonging to the neutral range; the average conductivity is 52.23 μS/cm, which indica.es that precipitations in Beijing are obviously polluted; SO 24? , NO3 ? are the most abundant anions with the average concentrations of 521 and 174 μeq·L?1, respectively; the average 2SO 4? /NO3? equivalent ratio is 3.1, which decreases by about 15% compared with the result of 1994; NH+ 4 and ca.+ are the most abundant ca.ions with the average concentrations of 376 and 397 μeq·L?1, respectively; formic acid, acetic acid and oxalic acid are the main organic acids with the average concentrations of 4.62, 4.60 and 1.17 μeq·L?1, respectively, accounting for 2% of the overall anions. Obvious differences between concentrations before and after precipitation are also observed by SJAC (Steam Jet Aerosol Collector), which shows the removal of particles from the atmosphere by precipitation.

关键词： precipitation, particles, ions, organic acids, sca.enging.

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Introduction of parameterized sea ice drag coefficients into ice free-drift modeling

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Acta Oceanologica.Sinica 2016年第1期35卷 53-59页

作者： LU Peng LI zhijun HAN Hongwei Laboratory of Coastal and Offshore Engineering Dalian University of Technology

Many interesting characteristics of sea ice drift depend on the atmospheric drag coefficient （ca. and oceanic drag coefficient （Cw）. Parameterizations of drag coefficients rather than constant values provide us a way to look insight into the dependence of these characteristics on sea ice conditions. In the present study, the parameterized ice drag coefficients are included into a free-drift sea ice dynamic model, and the wind factor a and the deflection angle θ between sea ice drift and wind velocity as well as the ratio of ca.to Cw are studied to investigate their dependence on the impact factors such as loca. drag coefficients, floe and ridge geometry. The results reveal that in an idealized steady ocean, ca.Cw increases obviously with the increasing ice concentration for small ice floes in the marginal ice zone, while it remains at a steady level （0.2-0.25） for large floes in the central ice zone. The wind factor a increases rapidly at first and approaches a steady level of 0.018 when A is greater than 20%. And the deflection angle ~ drops rapidly from an initial value of approximate 80° and decreases slowly as A is greater than 20% without a steady level like a. The values of these parameters agree well with the previously reported observations in Arctic. The ridging intensity is an important parameter to determine the dominant contribution of the ratio of skin friction drag coefficient （Cs＇/Cs） and the ratio of ridge form drag coefficient （Cr＇/Cr） to the value of ca.Cw, a, and 8, beca.se of the dominance of ridge form drag for large ridging intensity and skin friction for small ridging intensity among the total drag forces. Parameterization of sea ice drag coefficients has the potential to be embedded into ice dynamic models to better account for the variability of sea ice in the transient Arctic Ocean.

关键词： sea ice drag coefficient parameterization free drift modeling

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Iterative list decoding approach for Reed-Solomon codes

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The Journal of China Universities of Posts and Telecommunica.ions 2019年第3期26卷 8-14,24页

作者： Zhang zhijun Niu Kai Dong Chao Key Laboratory of Universal Wireless Communica.ions Beijing University of Posts and Telecommunications

A novel adaptively iterative list decoding(ILD) approach using for Reed-Solomon(RS) codes was investigated. The proposed scheme is exploited to reduce the complexity of RS Chase algorithm(ca. via an iterative decoding attempt mode. In each decoding attempt process, a test pattern is generated by flipping the bits of the least reliable positions(LRPs) within the received hard-decision(HD) vector. The ILD algorithm continues until a test pattern is successfully decoded by the underlying Berlekamp-Massey algorithm(BMA) of RS codes. Flipping within the same bits, the ILD algorithm provides the same test pattern set as the conventional RS ca. thus there is no degradation in error-rate performance. Without decoding all test patterns, the ILD algorithm ca. simplify the decoding complexity by its early termination. Simulation results show that the average complexity of the ILD algorithm is much lower than that of the conventional RS ca.and is similar to that of BMA decoding) at high signal-to-noise ratio(SNR) region with no less to the RS ca.decoding error-rate performance.

关键词： iterative decoding soft-decision decoding Reed-Solomon codes low-complexity decoding

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Fire occurrence in relation to bamboo dominance in the Qinling Mountains of China: Evidence from phytolith and charcoal records in Holocene sediments

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Science China Earth Sciences 2015年第7期58卷 1182-1190页

作者： Courtney Marie RAYLE Scott B.FRANKLIN LU zhijun School of Biologica. Sciences University of Northern Colorado Key Laboratory of Aquatic Botany and Watershed Ecology the Chinese Academy of Sciences

he internal genetic clock of semelparous mast-flowering bamboo species creates gregarious regions of flowering and death, thus leading to fuel-load accumulation that potentially promotes fire（Fire-Cycle Hypothesis）. Higher abundance of bamboo could be expected to provide greater fuel loads after flowering. Here, we investigated the possible link between bamboo dominance and fire occurrence. As the main food source for the giant panda in the Qinling Mountains of China, Bashania fargesii（Farges ca.ebrake） and Fargesia qinlingensis（Arrow Bamboo） dominate lower（1000–1900 m） and higher elevations（1800–2700 m）, respectively. Four soil profiles（elevation ranging from 1240 to 2170 m） in areas of known recent bamboo flowering events（~1980） and adjacent non-flowering sites were assessed for phytoliths and charcoal. Characteristic phytoliths were chosen to describe bamboo dynamics, and charcoal particles were extracted from the soil to reconstruct fire history. ca.bon 14 dating of soil charcoal samples was conducted using an accelerator mass spectrometry technique. In addition, we chose two depths（28–52 and 90–100 cm） in one Bashania profile（B. fargesii forest） and one Fargesia profile（F. qinlingensis forest） for phytolith dating. Our findings indica.e that bamboo has been a dominant component of these ecosystems almost for the entire profile; some 6400 yrs for Bashania and ca. 10000 yrs for the Fargesia. It is also clear from the charcoal and phytolith data that bamboo abundance and recent mast flowering were significa.tly related to fire occurrence for lower elevation Bashania while the higher elevation Fargesia was not. One of the four profiles had chronologica. charcoal records throughout and the oldest charcoal aged was ~1410 yr BP, suggesting an anthropogenic origin. The mixing of phytolith and charcoal made it unrealistic to describe temporal dynamics of bamboo and fire events, and thus our interpretation is cognizant of the dating discrepancies and conservative（less-sp

关键词： bamboo dynamics Bashania Fargesia fire cycle hypothesis phytolith Qinling Mountains

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