Fluorographene with Narrow Lateral Size and Thickness Distributions Prepared for Enhancing Lubrication Performance of Bentonite Grease

Fluorographene(FG)with narrow lateral size and thickness distributions was prepared by a liquid-phase exfoliation method,based on liquid cascade centrifugation.The Rtec MFT-5000 tribo-meter was used to investigate the lubricating performance of bentonite grease enhanced by the as-prepared FG.The results showed that the coefficient of friction and the wear volume of bentonite grease with 0.3 wt%FG were decreased by 20.4%and 44.9%,respectively,as compared to those of the base grease.The main reason is that FG can promote the formation of the tribo-chemical reaction film consisting of complex carbon oxide,Fe_(2)O_(3)and FeF_(3)on the friction surface,which can remarkably improve the performance of friction reduction and prevent the appearance of severe wear.

新型低GWP制冷剂在-100~200℃的应用研究进展

制冷剂是蒸气压缩循环中必不可少的工作流体,氢氟烷烃类化合物是目前制冷、空调和热泵设备中的主要制冷剂,但该类制冷剂会引起全球变暖等问题,因此亟需开发应用性能相似、环境性能友好的新型制冷剂。介绍了不同制冷剂在-100~200℃蒸气压缩循环应用场景中的使用现状,并综述了具有前景的低GWP制冷剂替代方案研究进展;在此基础上,对HFO-1234yf、HFO-1234ze(E)、HFO-1234ze(Z)、HCFO-1233zd(E)、HFO-1336mzz(Z) 5种低GWP制冷剂在实际应用系统中的最新研究及关键问题进行总结。

人工智能、产品创新与制造业适应性转型

人工智能(AI)对产品开发、运营和营销等企业价值链的影响正在改变制造业转型升级的机制与路径。围绕AI如何通过影响产品创新推动制造业转型升级,本文依托相关研究成果提炼AI区别于其他数字技术的核心创新特征,剖析AI对产品创新的影响机制,并通过AI影响个体、企业、产业的跨层次分析框架,从产品创新视角提出AI影响制造业转型升级的适应性变革概念模型,探讨AI通过产品创新影响制造业适应性转型的机制与路径,形成三个主要结论:(1)新社会主体、生成性、知识积累方式突变性构成AI区别于其他数字技术的三个核心创新特征;(2)AI作为新社会主体角色介入产品企划、结构工艺等开发环节,改变或增强了人类智能的产品开发思维,拓展了产品开发的知识边界;(3)AI增强产品创新与运营过程、市场营销和销售的全价值链即时互动和调整,构建起平衡制造敏捷性与用户敏捷性冲突的自适应调节机制,推动制造业通过产业快速自适应调节涌现出自适应间断平衡的转型路径。

人工智能驱动新质生产力形成的生成逻辑、运行机制与实践进路

新质生产力作为生产力发展的质变形态,体现了人工智能、大数据、云计算等新一代信息技术对传统生产方式和生产关系的根本性变革。人工智能对生产力的质性重塑集中体现在劳动者、劳动资料和劳动对象三大生产力要素上,即强化劳动者的劳动能力,引领劳动资料智能化与数字化革新,拓展劳动对象的范围和边界。作为新一轮产业变革的核心驱动力,人工智能从微观、中观、宏观三个层面促进新质生产力的形成。在企业微观层面,人工智能通过劳动要素替代效应推动劳动力需求向高技能的“脑力化”转换、人机交互模式的生产协同性赋能企业智能制造水平的高效能跃升、自动化生产的智能运转促进资源配置效率优化等路径实现企业生产要素配置的智能化形塑;在产业中观层面,人工智能促进传统产业数实深度融合、赋能数字化战略性新兴产业实现乘数增长、规模化应用重构智能产业链和创新链等途径促进产业转型升级,实现产业结构的智能化进阶;在国家宏观层面,人工智能技术的加速发展与应用赋能国家治理体系建设,推动社会治理精准化、政府决策科学化、公共服务高效化,形成了一种与新质生产力相适应的新型生产关系,实现国家治理的智能化转型。在生成式人工智能技术进化加速的新形势下,我国应进一步加快推动人工智能驱动新质生产力形成。一是坚持科技自主创新,以人工智能优化生产要素。健全人工智能人才培养机制,培育高技能水平的新型劳动者;提升人工智能场景创新能力,促进科技创新成果广泛应用;加快人工智能关键技术攻关,充分激活数据要素乘数效应潜能。二是加速推进产业数实深度融合,以人工智能大力推进现代化产业体系建设。推动传统产业智能化改造,实现基础设施连接能力迭代;培育壮大战略性新兴产业,构建人工智能的产业生态圈;探索先行先试改革,前瞻布局未来产业。三是建立健全人工智能治理体系,助力国家创新体系建设提质增效。以数字政府建设驱动国家治理的智能化转型;以智能赋能推动市场经济体系提质增效;以智能化发展提升国家创新体系效能。

Evaluation of Biological Characteristics of Bacteria Contributing to Biofilm Formation

Biofilm-associated microorganisms play crucial roles in terrestrial and aquatic nutrient cycling and in the biodegradation of environmental pollutants. Biofilm formation was determined for a total of 18 bacterial isolates obtained from the biofilms of wastewater treatment systems and of little carpolite in soil. Among these isolates, seven showed strong biofilm-forming capacity. The phylogenetic affiliation of the isolates showing high biofilm formation capacity was determined through 16S rDNA sequencing and the isolates were grouped into 7 bacterial species including Pseudornonas sp., Pseudomonas putida, Aeromonas caviae, Bacillus cereus, Pseudornonas plecoglossicida, Aeromonas hydrophila, and Comamonas testosteroni. The biofilm-forming capacity was closely related with flagella, exopolysaccharide, and extracellular protein. According to the coefficient of determination, the relative importance of the five biological characteristics to biofilm formation was, in order from greatest to least, exopolysaccharide 〉 flagella 〉 N-acyl-homoserine lactones （AHLs） signaling molecules 〉 extracellular protein 〉 swarming motility.

基于长短时记忆网络和生成对抗网络的VRB储能系统虚假数据注入攻击检测

随着信息技术的不断发展,直流微电网储能系统已成为深度融合的信息物理系统,而精确的荷电状态估计对储能系统的实时监测和安全稳定运行至关重要。针对全钒液流电池(vanadium redox flow battery,VRB)储能系统荷电状态估计中,由虚假数据注入攻击导致的异常数据检测问题,提出一种基于长短时记忆网络和生成对抗网络的检测方法。首先,建立了VRB等效电路模型和虚假数据注入攻击模型;然后,通过训练长短时记忆网络和生成对抗网络组成的循环网络,将长短时记忆神经网络嵌入生成对抗网络框架作为生成器和鉴别器来分析电池时序数据,通过判别网络中的判别损失误差和生成网络中的重构残差得到异常损失进行综合判断;最后,以CEC-VRB-5kW型号电池为对象,并构造不同强度的虚假数据攻击进行实验,验证检测方法的准确性与可行性。结果表明,与经典循环神经网络、随机森林、自编码器、长短时记忆网络检测方法进行对比,所提方法具有较高的检测精度,在VRB储能系统荷电状态估计中能够有效辨识虚假数据攻击。

Influence of furfural concentration on growth and ethanol yield of Saccharomyces kluyveri

Furfural is an important inhibitor in ethanol fermentation process using lignocellulosic hydrolysates as raw materials. In order to find out the furfural concentration range in which furfural inhibits the fermentation process, we used one strain Saccharomyces kluyveri selected from soil and cultured in several different furfural content media under low glucose concentration condition. Experiment results showed that microorganism growth was stimulated and dry cell weight decreased when furfural concentration in the medium was 0.25 mg/ml. Furfural had negative effect on cell growth when its concentration was above 1.00 mg/ml. At the same time, the strain growed better and had a higher glucose consumption rate in 5% original glucose concentration condition than in 3% original glucose concentration condition. The results showed that appropriate exaltation of original glucose concentration in stalk hydrolysates will increase the strain resistance to furfural.

Influence of Temperature and Frequency on Microwave Dielectric Properties of Lunar Regolith Simulant

The dielectric constant of the lunar regolith can directly influence the reflection coefficient and the trans-mission coefficient of the Moon′s surface, and plays an important role in the Moon research. In order to study the di-electric properties of the lunar regolith, the lunar regolith simulant was made according to the making procedure of the CAS-1 simulant made by Chinese Academy of Sciences. Then the dielectric constants of the lunar regolith simulant were measured with 85070E Aiglent Microwave Network Analyzer in the frequency ranging from 0.2 GHz to 20.0 GHz and at temperature of 25.1℃, 17.7℃, 13.1℃, 11.5℃, 9.6℃, 8.0℃, 4.1℃, -0.3℃, -4.7℃, -9.5℃, -18.7℃, -27.7℃, and -32.6℃, respectively. The Odelevsky model was employed to remove the influence of water in the air on the final effective dielectric constants. The results indicate that frequency and temperature have apparent influences on the dielectric constants of the lunar regolith simulant. The real parts of the dielectric constants increase fast over the range of 0.2 GHz to 3.0 GHz, but decrease slowly over the range of 4.0 GHz to 20.0 GHz. The opposite phenomenon occurs in the imaginary parts. The influences of the frequency and temperature on the brightness temperature were also estimated based on the radiative transfer equation. The result shows that the variation of the frequency and temperature results in great changes of the microwave brightness temperature emitting from the lunar regolith.

Modelling on seasonal lake ice evolution in central Asian arid climate zone: a case study

The seasonal cycle of ice thickness and temperature in Lake Wuliangsuhai,a typical shallow lake in the central Asian arid climate zone,was simulated using the HIGHTSI model and the MERRA-2 data as the meteorological forcing.The average ice growth rate was 0.64 cm·d^(−1) and −1.65 cm·d^(−1) for the growth and melting stage of the ice cover,respectively.The ice thickness agreed well with the field observations conducted in winter 2017,with a correlation coefficient of 0.97.The ice temperature field also agreed with observations in both daily variations and the vertical profile,and a better agreement in the daily amplitude and profile shape of ice temperature could be achieved if field data on physical properties of snow cover andmelting ice were available.This study proved the feasibility of both the HIGHTSI model and the MERRA-2 data for modeling the ice cover evolution in Lake Wuliangsuhai,providing a basis for a deep insight into the difference of lake ice evolution between central Asian arid climate zone and polar/sub-polar regions.

考虑韧性提升的输电网灾前预防检修多目标多阶段优化

极端气象灾害易使输电网发生大面积故障。输电网设备的健康程度影响着输电网抵御极端气象灾害物理层面的能力。为进一步提升输电网抗灾能力,减轻经济损失,从输电网韧性提升的角度出发,对输电网灾前预防检修策略进行研究。首先提出将灾害风险抵御力作为输电网灾时韧性评价指标,同时针对极端灾害的时空特性,采用场景分析法来计算韧性指标。根据输电网灾前预防检修的韧性提升、检修风险、经济性的要求,提出输电网灾前预防检修多目标多阶段优化模型,并采用NSGA-II算法与数学规划求解器结合的方法求解。采用IEEE RTS-79算例对优化模型的有效性进行了仿真验证。算例结果表明,文章所提优化模型能得出Pareto前沿以及最优折衷解,并以此得到最优灾前预防检修计划,在提升灾时韧性的同时控制灾前预防检修的风险与费用,从而帮助电网运行人员做出科学决策,具有较好的应用价值。

Evaluation of the net CO_2 uptake in the Canada Basin in the summer of 2008

The third Chinese National Arctic Research Expedition （CHINARE） was conducted in the summer of 2008. During the survey, the surface seawater partial pressure of CO2 （pCO2） was measured, and sea water samples were collected for CO2 measurement in the Canada Basin. The distribution of pCO2 in the Canada Basin was determined, the influencing factors were addressed, and the air-sea CO2 flux in the Canada Basin was evaluated. The Canada Basin was divided into three regions： the ice-free zone （south of 77°N）, the partially ice-covered zone （77°-80°N）, and the heavily ice-covered zone （north of 80°N）. In the ice-free zone, pCO2 was high （320 to 368 patm, 1 patm=0.101 325 Pa）, primarily due to rapid equilibration with atmospheric CO2 over a short time. In the partially ice-covered zone, the surface pCOs was relatively low （250 to 270 patm） due to ice-edge blooms and icemelt water dilution. In the heavily ice-covered zone, the seawater pCO2 varied between 270 and 300 laatm due to biological COs removal, the transportation of low pCOs water northward, and heavy ice cover. The surface seawater pCO2 during the survey was undersaturated with respect to the atmosphere in the Canada Basin, and it was a net sink for atmospheric CO2. The summertime net CO2 uptake of the ice-free zone, the partially ice-covered zone and the heavily ice-covered zone was （4.14±1.08）, （1.79±0.19）, and （0.57±0.03） Tg/a （calculated by carbon, 1 Tg=10^12 g）, respectively. Overall, the net COs sink of the Canada Basin in the summer of 2008 was （6.5＋1.3） Tg/a, which accounted for 4%-10% of the Arctic Ocean COs sink.

大数据驱动的产品创新商务智能——基于SSP框架的分析

人工智能改变产品创新主体,引发产品创新战略与流程变革。本文依据大数据合作资产理论,从企业与用户互动的适应性创新视角,通过逻辑推演分析提出大数据驱动的产品创新商务智能主体—战略—流程框架,以探讨人工智能影响制造产品创新的新机制。研究表明:首先,人与人工智能双向卷入形成要素组合与知识积累的双向反馈式增强机制,促使创新主体发生结构性改变,形成产品创新战略与流程变革的新基础。其次,企业人工智能认知战略与竞争战略、组织文化、商业模式和生态系统的匹配,共同影响人工智能在创新流程中的一体化应用。最后,模糊前端的全流程扩散、需求—解决方案对的非线性迭代和智能制造的生成式自测构成大数据驱动的产品创新流程的新特征。研究表明,主体—战略—流程框架适合分析大数据驱动的产品创新商务智能的新机制,可为人工智能与产品创新的关系研究提供新视角。

The role of lake heat flux in the growth and melting of ice

For shallow lakes,ice mass balance is largely dominated by thermodynamic processes.The heat flux from lake water plays a critical role for ice growth and melting.In this study,we applied a numerical thermodynamic lake model to investigate the sensitivity of the lake ice mass balance to the lake heat flux during the growth and melting periods.Several groups of modelling experiments forced by simplified climatological weather data have been carried out.Two sites,Lake Wuliangsuhai inInner Mongolia,China’s arid region and Lake Orajärvi in snowy Finnish Lapland,were investigated.Lake heat flux affects inversely proportional maximum ice thickness followed by ice break-up date.The solar radiation and surface albedo complicate the effect of lake heat flux on lake ice mass balance during melting season.With heavy snowfall,the increase of lake heat flux adds on the formation of granular ice but reduces the formation of columnar ice.Under climatological weather conditions,theice cover winter seasonal mean lake heat flux were 14 W·m^(−2) and 4 W·m^(−2) in Lake Wuliangsuhai and Lake Orajärvi,respectively.

基于YOLO v8和CycleGAN的红掌植株表型参数自动提取方法

植株表型参数是描述植物形态、结构和生理特征的定量化指标,可揭示植物生长规律,以及与环境因素之间的关系。现有的人工测量和激光雷达点云植株表型参数提取方法存在数据误差大、易损伤植株、成本高和数据量大等问题。为此,本文提出了一种基于YOLO v8和CycleGAN的红掌植株表型参数自动提取方法,利用双重注意力机制CBAM改进YOLO v8,提高模型特征提取能力,对红掌植株叶片进行检测与分割;通过Grabcut算法去除分割后图像背景区域特征,并利用VGG模型对其进行分类,分出完整型红掌植株叶片和缺失型红掌植株叶片;在CycleGAN的生成器中引入双重注意力机制和特征金字塔,提高模型多尺度特征的提取能力,引入SmoohL1损失函数,提升模型稳定性,对缺失型红掌植株叶片进行修复;提出一种表型参数提取算法(Phenotypic parameters extraction algorithms,PPEA),实现对红掌植株叶长、叶宽和叶面积的自动提取。以650幅自建数据集为例,对上述方法进行了比较与分析,实验结果证明,本文方法在红掌植株表型参数自动提取方面具有良好的效果。

改进3D-Octave卷积的高光谱图像分类方法

高光谱图像数据具有维度高、数据稀疏、空间光谱信息丰富等特点,针对空谱联合分类模型中高光谱图像卷积操作处理大片相同类别像素区域时会存在计算的空间冗余,3D卷积对深层空间纹理特征提取不充分,串行注意力机制结构不能充分考虑空谱相关性的问题,该文提出了改进的3D-Octave卷积高光谱图像分类模型。首先改进的3D-Octave卷积模块将输入的高光谱图像数据划分为高频特征图和低频特征图,减少空间信息冗余,提取多尺度的空间光谱特征,结合跨层融合策略,加强对浅层空间纹理特征和光谱特征的提取;随后利用2D卷积提取深层空间纹理特征并进行光谱特征融合;最后使用三维注意力机制跨纬度交互实现对有效特征的关注和激活,增强网络模型的性能和鲁棒性。结果表明,由于充分提取有效空谱联合特征,在印第安松树林(Indian Pines,IP)数据集的训练集比例为10%的条件下,OA,Kappa和AA分别为99.32%,99.13%和99.15%;在帕维亚大学(Pavia University,PU)数据集的训练集比例为3%的条件下,OA,Kappa和AA分别为99.61%,99.44%和99.08%。与5个主流分类模型进行对比,获得了更高的分类精度。

融合多重分解和差值修正的海浪波高预测研究

为了提升海浪波高预测精度,提出了融合多重分解和差值修正的海浪波高预测模型(J-DE-LSTM)。该模型采用自适应噪声完备集合经验模态分解,对波高数据进行一重分解,以及对分解后的残差分量进行二重分解;采用亲和力传播算法进行聚类降维并输人到长短期记忆网络进行预测获取初步预测值。建立波高观测值与初步预测值形成的差值序列进行三重分解,采用样本熵重构为趋势项和周期项并进行权重计算,构建粒子群算法优化极限学习机和LSTM的组合预测模型进行双轨并行预测;最后将预测结果与权重加权融合进行差值修正未来点位波高预测值。实验结果表明J-DE-LSTM模型较LSTM、TCN模型平均绝对误差提升约4.1%~11.5%,均方误差提升6.5%~15.2%。

湖冰作为极地海冰技术中试基地的探讨

极地海冰技术验证需在不同环境中开展测试,渤海海冰的不稳定性无法保障反复的长期试验时间,寻求利用国内寒区湖泊作为中试基地,解决室内缺少接近极地条件的中试难题。为此,在含章湖、青海湖、乌梁素海和呼和诺尔湖开展湖冰生消、物理性质、力学性质等调查研究,并与南、北极海冰的物理和力学性质进行对比评估。结果表明,含章湖、青海湖、乌梁素海湖和呼和诺尔湖均有时间充裕的冰封期。呼和诺尔湖冰厚最大,超过1 m;乌梁素海冰厚超过50 cm;含章湖和青海湖冰厚相似,最大冰厚超过30 cm。含章湖、青海湖和乌梁素海冰晶体均以柱状冰为主,与极地一年冰晶体结构相似。含章湖和青海湖冰的盐度及密度与北极夏季海冰相似。含章湖冰的单轴压缩强度比极地夏季海冰强度高;乌梁素海湖冰强度与南极普里兹湾固定冰强度相似。研究结果表明国内一些湖泊可作为极地海冰技术验证的中试基地。

感觉寻求与模糊容忍度对科学发明问题提出的影响

采用科学领域的发明问题实例为实验材料,探索感觉寻求与模糊容忍度对原型启发下创造性科学问题提出的影响。实验1以感觉寻求和原型处理为自变量,结果发现,在提出新颖性科学问题上,感觉寻求相对高分组个体受原型启发提出新颖性问题的提升程度明显高于低分组;实验2以模糊容忍度和原型处理为自变量,结果发现,相对高模糊容忍度个体更善于利用原型信息,提出更多新颖有效性科学问题。此外,原型条件下个体提出新颖性或新颖有效性科学问题的比率更高。研究结果表明,原型对创造性科学问题提出具有稳定的启发效应,感觉寻求与模糊容忍度是原型启发下创造性科学问题提出的重要人格特质,且对新颖性和新颖有效性科学问题提出产生不同影响。

木材老化对古建筑木梁抗弯性能的影响分析

为研究木材老化对古建筑木梁抗弯性能的影响,分析了木材的老化机理,采用等效截面法并结合国内木梁老化深度经验公式,提出了老化木梁抗弯承载力退化模型,并对某古建筑的木梁进行了承载力退化评估。对未老化与老化木梁进行了单调加载数值模拟,并通过试验验证了模型的合理性;在此基础上,进一步分析了老化均匀度与老化深度对木梁抗弯性能的影响。结合《木结构设计标准》(GB 50005—2017)中受弯构件的承载力计算公式,提出了考虑老化影响的木梁抗弯承载力折减系数计算公式。结果表明:老化对木梁抗弯承载力的影响与老化均匀度呈线性相关,与老化深度呈一元二次多项式关系。老化深度越深且老化均匀度越大,木梁承载力越低。

双侧极重度感音神经性聋患儿人工耳蜗植入效果分析

目的分析双侧极重度感音神经性聋患儿人工耳蜗植入效果。方法选取2018年2月~2022年2月本院接诊的80例双侧极重度感音神经性聋患儿,将40例非对称性听力损失患儿纳入对照组,行单侧人工耳蜗植入;将40例对称性听力损失患儿纳入观察组,行双侧人工耳蜗植入;分析两组开机前和干预6、12、36个月后的听觉行为分级(CAP)、言语可懂度分级(SIR),并建立多因素logistic模型,分析双侧人工耳蜗植入后影响CAP、SIR评分的独立危险因素。结果观察组干预后12、36个月CAP、SIR评分显著高于对照组(P<0.05)。多因素logistic分析显示,年龄>3岁、术前未使用助听器、植入时间<1年、内耳畸形是影响双侧人工耳蜗植入儿童CAP、SIR评分的独立危险因素(P<0.05)。结论双侧人工耳蜗植入是极重度感音神经性聋患儿听觉补偿的有效手段,年龄、植入时间、内耳畸形等因素可能影响患儿的听觉、言语功能康复,尽早为患儿植入双侧人工耳蜗,加强相关干预,才能有效促使患儿听觉言语功能康复。