Acetic acid additive in NaNO_(3)aqueous electrolyte for long-lifespan Mg-air batteries

Mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density,environmental sustainability,and cost-effectiveness.However,the fast hydrogen evolution reaction(HER)in NaCl-based aqueous electrolytes impairs the performance of Mg-air batteries and leads to poor specific capacity,low energy density,and low utilization.Thus,the conventionally used NaCl solute was proposed to be replaced by NaNO_(3)and acetic acid additive as a corrosion inhibitor,therefore an electrolyte engineering for long-life time Mg-air batteries is reported.The resulting Mg-air batteries based on this optimized electrolyte demonstrate an improved discharge voltage reaching~1.8 V for initial 5 h at a current density of 0.5 mA/cm^(2) and significantly prolonged cells'operational lifetime to over 360 h,in contrast to only~17 h observed in NaCl electrolyte.X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed to analyse the composition of surface film and scanning electron microscopy combined with transmission electron microscopy to clarify the morphology changes of the surface layer as a function of acetic acid addition.The thorough studies of chemical composition and morphology of corrosion products have allowed us to elucidate the working mechanism of Mg anode in this optimized electrolyte for Mg-air batteries.

Novel sandwich structured glass fiber Cloth/Poly(ethylene oxide)-MXene composite electrolyte

Recently,poly(ethylene oxide)(PEO)-based solid polymer electrolytes have been attracting great attention,and efforts are currently underway to develop PEO-based composite electrolytes for next generation high performance all-solid-state lithium metal batteries.In this article,a novel sandwich structured solid-state PEO composite electrolyte is developed for high performance all-solid-state lithium metal batteries.The PEO-based composite electrolyte is fabricated by hot-pressing PEO,LiTFSI and Ti_(3)C_(2)T_(x) MXene nanosheets into glass fiber cloth(GFC).The as-prepared GFC@PEO-MXene electrolyte shows high mechanical properties,good electrochemical stability,and high lithium-ion migration number,which indicates an obvious synergistic effect from the microscale GFC and the nanoscale MXene.Such as,the GFC@PEO-1 wt%MXene electrolyte shows a high tensile strength of 43.43 MPa and an impressive Young's modulus of 496 MPa,which are increased by 1205%and 6048%over those of PEO.Meanwhile,the ionic conductivity of GFC@PEO-1 wt%MXene at 60℃ reaches 5.01×10^(-2) S m^(-1),which is increased by around 200%compared with that of GFC@PEO electrolyte.In addition,the Li/Li symmetric battery based on GFC@PEO-1 wt%MXene electrolyte shows an excellent cycling stability over 800 h(0.3 mA cm^(-2),0.3 mAh cm^(-2)),which is obviously longer than that based on PEO and GFC@PEO electrolytes due to the better compatibility of GFC@PEO-1 wt%MXene electrolyte with Li anode.Furthermore,the solid-state Li/LiFePO_(4) battery with GFC@PEO-1 wt%MXene as electrolyte demonstrates a high capacity of 110.2–166.1 mAh g^(-1) in a wide temperature range of 25–60C,and an excellent capacity retention rate.The developed sandwich structured GFC@PEO-1 wt%MXene electrolyte with the excellent overall performance is promising for next generation high performance all-solid-state lithium metal batteries.

Unraveling the incompatibility mechanism of ethylene carbonate-based electrolytes in sodium metal anodes

Ethylene carbonate(EC)is widely used in lithium-ion batteries due to its optimal overall performance with satisfactory conductivity,relatively stable solid electrolyte interphase(SEI),and wide electrochemical window.EC is also the most widely used electrolyte solvent in sodium ion batteries.However,compared to lithium metal,sodium metal(Na)shows higher activity and reacts violently with EC-based electrolyte(NaPF_(6)as solute),which leads to the failure of sodium metal batteries(SMBs).Herein,we reveal the electrochemical instability mechanism of EC on sodium metal battery,and find that the com-bination of EC and NaPF_(6) is electrically reduced in sodium metal anode during charging,resulting in the reduction of the first coulombic efficiency,and the continuous consumption of electrolyte leads to the cell failure.To address the above issues,an additive modified linear carbonate-based electrolyte is provided as a substitute for EC based electrolytes.Specifically,ethyl methyl carbonate(EMC)and dimethyl carbon-ate(DMC)as solvents and fluoroethylene carbonate(FEC)as SEI-forming additive have been identified as the optimal solvent for NaFP_(6)based electrolyte and used in Na_(4)Fe_(3)(PO_(4))_(2)(P_(2)O_(7))/Na batteries.The batter-ies exhibit excellent capacity retention rate of about 80%over 1000 cycles at a cut-off voltage of 4.3 V.

3D spiny AlF_(3)/Mullite heterostructure nanofiber as solid-state polymer electrolyte fillers with enhanced ionic conductivity and improved interfacial compatibility

Lithium metal batteries assembled with solid-state electrolyte can offer high safety and volumetric energy density compared to liquid electrolyte.The polymer solid-state electrolytes of poly(ethylene oxide)(PEO)are widely used in lithium metal solid-state batteries due to their unique properties.However,there are still some defects such as low ionic conductivity at room temperature and weak inhibition of lithium dendrite growth.Herein,the spiny inorganic nanofibers heterostructure with mullite whiskers grown on the surface of aluminum fluoride(AlF_(3))nanofibers are introduced into the PEOLi TFSI electrolytes for the first time to prepare composite solid-state electrolytes.The AlF_(3)as a strong Lewis acid can adsorb anions and promote the dissociation of Li salts.Besides,the specially threedimensional(3D)structure enlarges the effective contacting interface with the PEO polymer,which allows the lithium ions to be transported not only along the large aspect ratio of AlF3nanofibers,but also along the mullite phase in the transmembrane direction rapidly.Thereby,the transport channel of lithium ions at the spiny inorganic nanofibers-polymer interface is further improved.Benefiting from these advantages,the obtained composite solid-state electrolyte has a high ionic conductivity of 1.58×10^(-4)S cm^(-1)at 30℃and the lithium ions transfer number of 0.53.In addition,the AlF3has strong binding energy with anions,low electronic conductivity and wide electrochemical stability window,and reduced nucleation overpotential of lithium during cycling,which is positive for lithium dendrite suppression in solid-state electrolytes.Thus,the assembled symmetric Li/Li symmetric batteries exhibit stable cycling performance at different area capacities of 0.15,0.2,0.3 and 0.4 m A h cm^(-2).More importantly,the LiFePO_(4)(LFP)/Li battery still has 113.5 m A h g-1remaining after 400 cycles at 50℃and the Coulomb efficiency is nearly 100%during the long cycle.Overall,the interconnected structure of 3D spiny inorganic heterostructure nanofiber constitutes fast and uninterrupted lithium ions transport channels,maximizing the synergistic effect of interfacial transport of inorganic fillers and reducing PEO crystallinity,thus providing a novel approach to high performance solid-state electrolytes.

Preparing 3D Perovskite Li_(0.33)La_(0.557)TiO_(3)Nanotubes Framework Via Facile Coaxial Electro-Spinning Towards Reinforced Solid Polymer Electrolyte

It is of significance to construct continuous multiphase percolation channels with fast lithium-ion pathway in hybrid solid electrolytes.3D ceramic nanostructure frameworks have attracted great attention in this field.Herein,the three-dimensional perovskite Li_(0.33)La_(0.557)TiO_(3)nanotubes framework(3D-LLTO-NT)is fabricated via a facile coaxial electro-spinning process followed by a calcination process at 800°C.The hybrid polymer electrolyte of 3DLLTO-NT framework and poly(ethylene carbonate)(3D-LLTO-NT@PEC)shows improved ionic conductivity of 1.73×10^(-4)S cm^(-1)at ambient temperature,higher lithium-ion transference number(t_(Li)^(+))of 0.78 and electrochemical stability window up to 5.0 V vs Li/Li^(+).The all-solid-state cell of LiFePO_(4)/3D-LLTO-NT@PEC/Li delivers a high specific capacity of 140.2 mAh g^(-1)at 0.1 C at ambient temperature.This outstanding performance is attributed to the 3D ceramic nanotubes frameworks which provide fast lithium ion transfer pathway and stable interfaces.

基于改进DeepLabv3+的轻量化作物杂草识别方法

为在存储资源与计算能力有限的设备上实现田间作物和杂草的识别,本文提出一种基于改进DeepLabv3+的轻量化语义分割网络。首先,以MobileNet v2作为DeepLabv3+的特征提取骨干网络,提出双分支残差模块替换倒残差模块,并删除后两层卷积以降低模型参数量。其次,在空洞空间金字塔池化(Atrous Spatial Pyramid Pooling,ASPP)模块中引入分组逐点卷积,使用深度扩张卷积替换标准卷积,并将卷积后的特征图进行多尺度特征融合增强对作物和杂草深层特征的提取能力。最后,将原有的非线性激活函数替换为Leaky ReLU激活函数来提升分割精度。实验结果表明:改进后网络的mIOU达到86.75%,参数量仅为0.69M,FPS达到了98,与原始DeepLabv3+以及3个典型轻量化语义分割网络的相比,参数量最小,在对比的轻量化网络中具有最高的分割精度。

罗汉果皂苷V对RSL3诱导的SH-SY5Y细胞铁死亡的抑制作用及其机制

目的:探讨罗汉果皂苷V(MV)对铁死亡诱导剂RAS选择性致死分子3(RSL3)诱导的人神经母细胞瘤SH-SY5Y细胞铁死亡的抑制作用及可能机制。方法:用RSL3诱导SH-SY5Y细胞建立铁死亡模型。MTT法检测细胞活力;倒置显微镜观察细胞形态;亚铁离子荧光探针FerroFarRed检测细胞内亚铁离子含量;线粒体红色荧光探针MitoTracker Red CMXRos检测线粒体膜电位(MMP);超氧化物阴离子荧光探针二氢乙啶和线粒体超氧化物红色荧光探针MitoSoX Red分别检测细胞内和线粒体内活性氧(ROS)。微板法检测细胞谷胱甘肽(GSH)和丙二醛(MDA)水平。Western blot检测脂酰辅酶A合成酶长链家族成员4(ACSL4)、环加氧酶2(COX-2、)谷胱甘肽过氧化物酶4(GPX4)和溶质载体家族7成员11(SLC7A11)蛋白表达水平。分子对接技术预测MV与ACSL4、COX-2、GPX4和SLC7A11的靶向关系。结果:与control组相比,RSL3组SH-SY5Y细胞活力显著降低(P<0.01),细胞内亚铁离子含量、细胞内和线粒体内ROS水平及MDA水平显著升高(P<0.05或P<0.01),MMP和GSH水平显著降低(P<0.01),ACSL4和COX-2蛋白表达水平显著升高,而GPX4和SLC7A11蛋白表达水平显著降低(P<0.01),提示成功建立了细胞铁死亡模型。MV处理使细胞活力显著升高(P<0.05),细胞内亚铁离子含量、细胞内和线粒体内ROS水平及MDA水平显著降低(P<0.01),MMP和GSH水平显著升高(P<0.05或P<0.01);ACSL4和COX-2蛋白水平显著降低,而GPX4和SLC7A11蛋白水平显著升高(P<0.05或P<0.01)。分子对接结果显示,MV与铁死亡核心蛋白ACSL4、COX-2、GPX4和SLC7A11存在结合位点。结论:MV可抑制RSL3诱导的SH-SY5Y细胞铁死亡的发生,其机制可能与激活SLC7A11/GPX4和抑制ACSL4/COX-2有关。

改进DeepLab v3+模型下的梯田遥感提取研究

[目的与意义]梯田作为农业生产的关键要素之一,其面积估算对于农业政策制定、土地规划和资源管理至关重要。为解决复杂的地形条件、种植环境导致传统遥感数据和监测方法难以开展梯田自动化提取问题,探索一种利用深度学习技术在高分辨率遥感影像中精准提取梯田面积的方法。[方法]以休耕期梯田高分六号影像构建语义分割数据集,同时提出一种改进的DeepLab v3+模型。该模型使用轻量级网络MobileNet v2作为骨干网络,为了同时兼顾局部细节和全局语境,使用多尺度特征融合(Multi-scale Feature Fusion module,MSFF)模块代替空洞空间金字塔池化(Atrous Spatial Pyramid Pooling,ASPP)模块,利用扩张率依次增大的空洞卷积级联模式改善信息丢失的问题。此外,对浅层特征和深层特征使用坐标注意力机制以加强网络对于目标的学习。[结果与讨论]利用红、绿和近红外波段组合方式在梯田提取的精度和效果上表现最佳。相比于原始DeepLab v3+网络,精确率、召回率、F_(1)评分和交并比指标分别提升4.62%、2.61%、3.81%和2.81%。此外,与UNet和原始DeepLab v3+相比,改进的DeepLab v3+在参数量上和浮点运算数有着更为优越的性能,其参数量仅为UNet的28.6%和原始DeepLab v3+的19.5%,同时浮点运算数仅为UNet和DeepLab v3+的1/5。这不仅提高了计算效率,也使得改进后的模型更适用于资源有限或计算能力较低的环境中。[结论]深度学习在高分辨率遥感影像梯田识别中具有较高的精度,有利于为梯田精细化监测和管理提供参考依据。

改进Deeplabv3+的双注意力融合作物分类方法

近年来,卷积神经网络(convolutional neural networks,CNN)在农作物分类研究中不断取得新进展,但在建模长期依赖关系方面表现出一定的局限性,对农作物全局特征的捕获存在不足。针对以上问题,将Transformer引入Deeplab v3+模型,提出了一种用于无人机影像农作物分类的并行分支结构--DeepTrans(Deeplab v3+with Trans-former)模型。DeepTrans以一种并行的方式将Transformer和CNN结合在一起,利于全局特征与局部特征的有效捕获。通过引入Transformer来增强图像中信息的远距离依赖关系,提高了作物全局信息的提取能力;加入通道注意力机制和空间注意力机制加强Transformer对通道信息的敏感度及ASPP(atrous spatial pyramid pooling)对作物空间信息捕获能力。实验结果表明,DeepTrans模型在MIoU指标上可达0.812,相较于Deeplab v3+模型提高了3.9%,该模型在五类作物的分类中精度均有提升,对于容易错分的甘蔗、玉米和香蕉三种作物,其IoU分别提高了2.9%、4.7%、13%。由此可见,DeepTrans模型在农作物分类图像的内部填充和全局预测方面有着更好的分割效果,有助于更准确地监测农田作物的种植结构及规模。

基于v3洋葱域名的比特币地址威胁程度分析

比特币可以在不透露使用者身份的情况下进行交换,导致其成为不法分子在暗网上进行违法活动的主要方式。为了追踪比特币非法交易,传统方法根据比特币的伪匿名性,在整个区块链上进行启发式地址聚类,没有充分利用比特币地址在暗网上的信息。2021年Tor官方全面启用v3洋葱域名,使得以往的v2洋葱域名数据无法再作为分析的依据。设计并实现基于v3洋葱域名的比特币地址威胁程度的一体化分析框架TLAFDB。信息收集模块使用境外服务器解决地域限制并设置socks5h代理以支持暗网爬虫运行,使用洋葱种子地址在暗网中爬行收集最新的v3洋葱域名数据,信息清洗模块采用可同时覆盖Base58和Bech32编码的正则表达式以提取v3洋葱域名网页中的比特币地址,通过区块链搜索引擎Blockchain.com筛选存在真实交易的比特币地址,并建立其和所在v3洋葱域名的关联关系,信息分析模块采用人工分析和关键词匹配相结合的方法分类v3洋葱域名,赋予其关联的比特币地址类别和流行度并判定威胁程度。实验结果表明,TLAFDB收集了23627个v3洋葱域名网页,提取并分析1141个存在真实交易的比特币地址的类别、流行度和威胁程度,发现在暗网中同一个比特币地址常出现在大量的镜像洋葱域名网页上,超过95%的比特币地址被恶意使用,并且庞氏骗局交易量占高危比特币地址总交易量的99%。

基于改进MobileNet v3的苹果叶片病害识别研究

为解决移动端和嵌入式设备中苹果叶片病害识别准确率不高、效率低下的问题,提出了一种新的基于MobileNet v3网络的分类模型,以实现更加高效和准确的苹果叶片病害识别。首先通过数据增广方法增强数据集,按照9∶1的比例划分训练集和验证集;然后在MobileNet v3网络核心倒残差结构的升维部分引入全维动态卷积,以加强对不同维度注意力权重的学习,从而增强网络的拟合能力;最后在降维部分引入修改后的ConvNext Block模块,减少信息损失并增加全局感受野。采用PyTorch作为分类网络的深度学习框架,使用交叉熵损失函数作为分类任务的损失函数,Adam作为优化器,通过多组对比试验可知,MobileNet v1、MobileNet v2、ResNet34、MobileNet v3以及改进后的MobileNet v3 ODConvNext网络的准确率分别为94.5%、95.7%、97.2%、96.9%及97.5%。可见,MobileNet v3 ODConvNet网络拥有最高的Top-1准确率,相较于MobileNet v3网络和结构更为复杂的ResNet34网络分别提升了0.6、0.3百分点;在运算频率方面,相对于MobileNet v3网络仅增加了1.00×10^(6)次/s,并且仅为ResNet34网络参数量的11.84%。因此,该试验结果证明了改进后的MobileNet v3 ODConvNext模型具有更加轻量级和更高准确率的优点,满足在移动端真实场景下进行苹果叶片病害识别的要求,有助于苹果叶片病害的防治工作。

乙腈-水系混合电解液对Zn-Na_(3)V_(2)(PO_(4))_(3)电池电化学稳定性的影响

Na_(3)V_(2)(PO_(4))_(3)正极材料具有稳定的三维框架结构、较高的工作电压和相对成熟的制备工艺,近年来也逐渐用于水系锌离子电池中。然而,二价Zn^(2+)的脱嵌和活泼的水系反应环境会加速磷酸盐晶格的破坏。本文在Zn-Na_(3)V_(2)(PO_(4))_(3)电池体系的水系电解液中加入适量的乙腈(AN),研究电解液中AN与水的比例对离子溶剂化结构和电化学行为的影响规律,并通过非原位XRD探究Na_(3)V_(2)(PO_(4))_(3)晶体结构的演变。结果表明:过少的AN会加快正极材料晶格框架的破坏,而过多的AN会减缓电极反应动力学;在含有适量AN的电解液中,Zn-Na_(3)V_(2)(PO_(4))_(3)电池不但在50 mA/g的电流密度下具有91.4 mA·h/g的较高比容量,同时在500 mA/g的电流密度下可以稳定循环1000次且无明显容量衰退。

基于改进MobileNet v3的苹果叶片病害识别方法及移动端应用

准确识别苹果叶片病害种类以进行及时防治对于苹果增量增产具有重要的意义,为实现在移动设备实时对苹果叶片进行病害识别,提高苹果的产量,减少种植者的损失。首先收集了黑星病、斑点落叶病、锈病、白粉病、混合病、褐斑病等6种苹果叶部病害和健康叶片的图像,并使用Retinex算法对图像进行数据增强,以提高数据集质量,然后将数据集按照8∶1∶1的比例划分为训练集、验证集和测试集;其次对MobileNet v3网络模型进行改进优化调整,在精简网络结构的同时减少冗余参数,并在非线性激活层后加入批归一化层,以提高网络的特征提取能力;同时,为了提升在低精度移动设备上的准确性和模型运行效率,将全连接层中的激活函数替换为ReLU6函数;最后,在模型训练时使用动量随机梯度下降优化器来进行模型权重系数的寻优,以减少训练时间和达到更高的分类准确率。试验结果表明,改进后的MobileNet v3-A3网络对苹果叶片病害图像的识别准确率为96.48%,模型权重为2.98 MB,识别速率为8.82 ms/幅图片,与其他同量级卷积神经网络相比识别精度更高、模型更小、识别速度更快。本研究使用Android Studio将权重模型封装到安卓软件中,实现了移动设备对苹果叶片病害的准确快速识别。

香烟烟雾提取物对破骨细胞体积及整合素αvβ3基因表达的影响

目的探讨香烟烟雾提取物(cigarette smoke extract,CSE)对破骨细胞体积及整合素αvβ3基因表达的影响。方法首先制作CSE溶液,实验采用7周龄C57BL/6J小鼠骨髓单个核细胞加入M-CSF和RANKL诱导生成破骨细胞,将浓度为5%的CSE加入实验组破骨细胞作用3 d,对照组不加入CSE。通过Trap染色识别对照组和实验组破骨细胞并于光镜下采图;通过甲苯胺蓝染色识别两组破骨细胞在骨片上形成的骨陷窝并于光镜下采图,均用NIH imageJ计算数量及面积。用实时荧光定量聚合酶链反应,以GAPDH作为内参,最后通过2-ΔΔCT计算,以检测Trap、CTR以及整合素αvβ3 mRNA表达水平。通过Western blot检测整合素αvβ3蛋白表达。结果破骨细胞表面积及细胞核数量的计量表明,实验组诱导形成的破骨细胞显著大于对照组(P<0.01)。实验组骨片上吸收陷窝数量及面积明显多于对照组(P<0.05),CSE处理组的TRAP mRNA水平为1.16±0.13,明显高于对照组(P<0.05),CTRmRNA水平为0.38±0.04,明显低于对照组(P<0.01)。CSE处理组的整合素αvβ3mRNA水平为1.75±0.05,显著高于对照组(P<0.01),蛋白质印迹分析结果也明显高于对照组(P<0.05)。结论CSE能显著增加破骨细胞的体积并上调整合素αvβ3的基因表达,并可能对骨吸收有促进作用。

基于改进YOLO v3的轴承端面缺陷检测算法

为提高轴承端面缺陷检测的速度以及检测精度,提出一种基于改进YOLO v3的轴承端面缺陷检测算法。首先,对图像数据集进行数据增强处理以防止产生过拟合现象;其次,通过改进K-means聚类算法重新聚类出目标检测的Anchor Boxes,并引入SKNet注意力机制模块对原网络结构以及输出层结构进行改进;最后对改进的YOLO v3算法进行实验验证,并与原YOLO v3算法进行对比分析。结果表明,改进后的YOLO v3算法相比原YOLO v3算法对轴承端面缺陷检测的mAP值提升了7.03%,检测速度提升了34.7帧/s,验证了改进算法的有效性。

基于改进MobileNet v3-Small模型的草莓病害识别方法

为了对草莓病害进行及时的诊断与治疗而提升草莓产量,将深度学习与农业生产结合以快速高效地进行病害检测。传统神经网络进行病害识别时间较长,参数量较大,难以迁移到移动端设备上,基于此提出一种改进MobileNet v3-Small模型的识别方法。首先收集了7类常见草莓病害图像样本(如角斑病、叶斑病等),通过旋转、镜像等多种数据增强方式对图像进行处理以增加图片数量,提高模型泛化能力。接着以MobileNet v3-Small模型为基础,基于原始Inception_A提出部分卷积权值共享的多尺度卷积结构,以更高效地提取草莓病害不同尺度特征。随后,在网络深层引入了ULSAM轻量级子注意力机制,形成草莓病害更高层次的抽象表示。同时,将深度可分离卷积中的第2个PW卷积替换为CondConv卷积形成PDC结构,克服了PW卷积只拥有局部感受野的缺陷,同时也降低了模型参数量。试验结果表明,改进后的MobileNet v3-Small模型准确率达到98.62%,较原模型94.91%的准确率提高了3.71百分点,并且参数量减少了0.04 M,远优于同级轻量化模型,且以远低于ResNet18的参数量取得更好的特征提取效果。综上所述,本研究所提出的改进后的MobileNet v3_Small模型能更好地在真实场景下进行草莓病害识别,为草莓生产贡献了一份力量,助力智慧农业发展。

基于Kinect V2和Unity3D的机械臂人机交互系统

针对人机交互方式存在不直观、操作复杂等问题,论文利用手部追踪技术开发出一种基于Kinect V2和Unity3D的人机交互系统,用户可以直接挥动手部就可以控制机械臂运动,交互方式更加简单、直观和灵活。该系统是通过Kinect V2来获得手部移动轨迹来实现手部追踪,并在Unity3D平台上进行交互系统的开发。利用FABRIK算法和贝塞尔曲线分别实现了逆运动学求解和运动路径的记录,通过C#编写所需的脚本功能并开发出了两种交互模式,分别为实时控制模式和示教模式,两种模式均可通过UI面板进行选择。最后对两种模式分别进行实验,实验结果证明了该系统的可行性。

LAIR-1通过阻断JAK2 V617F突变的人HEL细胞JAK/STAT和PI3K/AKT/mTOR信号通路抑制其增殖并促进其凋亡

目的研究人白细胞相关免疫球蛋白样受体1(LAIR-1)对Janus激酶2(JAK2)V617F突变的人急性髓系白血病HEL细胞JAK/信号转导子与转录激活子(STAT)和磷脂酰肌醇3激酶/蛋白激酶B/哺乳动物雷帕霉素靶蛋白(PI3K/AKT/mTOR)信号通路的调节作用,以及对细胞增殖和凋亡的影响。方法采用反转录PCR和基因测序鉴定JAK2 V617F突变;应用免疫共沉淀和Western blot法鉴定LAIR-1募集的蛋白酪氨酸磷酸酶(PTP)种类;采用CCK-8法检测HEL细胞的增殖;采用异硫氰酸荧光素标记的膜联素Ⅴ/碘化丙啶(annexinⅤ-FITC/PI)双标记结合流式细胞术检测HEL细胞的凋亡率;采用Western blot法检测JAK/STAT和PI3K/AKT/mTOR通路蛋白酪氨酸磷酸化水平及细胞周期蛋白D1(cyclin D1)、Bcl2相关X蛋白(BAX)和B细胞淋巴瘤因子2(Bcl2)的蛋白表达。结果在JAK2 V617F突变的HEL细胞中,LAIR-1与其配体胶原蛋白结合后可募集含Src同源域2磷酸酶2(SHP-2);LAIR-1可以下调HEL细胞JAK2、STAT1、STAT3、STAT5、AKT和mTOR的蛋白酪氨酸磷酸化水平,并能够显著抑制cyclin D1和Bcl2的表达,而对BAX的表达水平未见显著影响;LAIR-1能够明显抑制HEL细胞的增殖,促进HEL细胞凋亡。结论在JAK2 V617F突变的人白血病HEL细胞中,LAIR-1可通过募集SHP-2抑制JAK/STAT和PI3K/AKT/mTOR信号通路的活化,进而抑制HEL细胞的增殖,促进细胞凋亡。

A three-dimensional co-continuous network structure polymer electrolyte with efficient ion transport channels enabling ultralong-life all solid-state lithium metal batteries

Solid polymer electrolytes(SPEs)have emerged as one of the most promising candidates for the construction of solid-state lithium batteries due to their excellent flexibility,scalability,and interface compatibility with electrodes.Herein,a novel all-solid polymer electrolyte(PPLCE)was fabricated by the copolymer network of liquid crystalline monomers and poly(ethylene glycol)dimethacrylate(PEGDMA)acts as a structural frame,combined with poly(ethylene glycol)diglycidyl ether short chain interspersed serving as mobile ion transport entities.The preparaed PPLCEs exhibit excellent mechanical property and out-standing electrochemical performances,which is attributed to their unique three-dimensional cocontinuous structure,characterized by a cross-linked semi-interpenetrating network and an ionic liquid phase,resulting in a distinctive nanostructure with short-range order and long-range disorder.Remarkably,the addition of PEGDMA is proved to be critical to the comprehensive performance of the PPLCEs,which effectively modulates the microscopic morphology of polymer networks and improves the mechanical properties as well as cycling stability of the solid electrolyte.When used in a lithiumion symmetrical battery configuration,the 6 wt%-PPLCE exhibites super stability,sustaining operation for over 2000 h at 30 C,with minimal and consistent overpotential of 50 mV.The resulting Li|PPLCE|LFP solid-state battery demonstrates high discharge specific capacities of 160.9 and 120.1 mA h g^(-1)at current densities of 0.2 and 1 C,respectively.Even after more than 300 cycles at a current density of 0.2 C,it retaines an impressive 73.5%capacity.Moreover,it displayes stable cycling for over 180 cycles at a high current density of 0.5C.The super cycle stability may promote the application for ultralong-life all solid-state lithium metal batteries.

Co8W6Mo5Cr4V3粉末高速钢的热变形行为

采用熔炼、电渣重熔和气雾化法制备Co8W6Mo5Cr4V3粉末,再通过热等静压制备Co8W6Mo5Cr4V3粉末高速钢。在不同变形条件下进行热压缩实验,研究粉末高速钢的热变形行为,根据获得的应力-应变曲线,建立热变形本构方程,绘制热加工图。结果表明:Co8W6Mo5Cr4V3粉末高速钢的流变应力随变形温度升高或应变速率减小而减小;通过本构方程预测的流变应力和实验得到的流变应力间的相关系数为0.995,可用此方程对粉末高速钢在不同变形条件下的应力进行预测;根据热加工图,粉末高速钢最优的变形温度为1 100~1 150℃,应变速率为0.1~1.0 s^(-1)。