Optical properties of La_(2)O_(3) and HfO_(2) for radiative cooling via multiscale simulations

Radiative cooling materials have gained prominence as a zero-energy solution for mitigating global warming.However,a comprehensive understanding of the atomic-scale optical properties and macroscopic optical performance of radiative cooling materials remains elusive,limiting insight into the underlying physics of their optical response and cooling efficacy.La_(2)O_(3)and HfO_(2),which represent rare earth and third/fourth subgroup inorganic oxides,respectively,show promise for radiative cooling applications.In this study,we used multiscale simulations to investigate the optical properties of La_(2)O_(3)and HfO_(2)across a broad spectrum.First-principles calculations revealed their dielectric functions and intrinsic refractive indices,and the results indicated that the slightly smaller bandgap of La_(2)O_(3)compared to HfO_(2)induces a higher refractive index in the solar band.Additionally,three-phonon scattering was found to provide more accurate infrared optical properties than two-phonon scattering,which enhanced the emissivity in the sky window.Monte Carlo simulations were also used to determine the macroscopic optical properties of La_(2)O_(3)and HfO_(2)coatings.Based on the simulated results,we identified that the particle size and particle volume fraction play a dominant role in the optical properties.Our findings underscore the potential of La_(2)O_(3)and HfO_(2)nanocomposites for environment-friendly cooling and offer a new approach for high-throughput screening of optical materials through multiscale simulations.

Early peripheral perfusion index predicts 28-day outcome in patients with septic shock

BACKGROUND:To investigate the prognostic value of the peripheral perfusion index(PPI)in patients with septic shock.METHODS:This prospective cohort study,conducted at the emergency intensive care unit of Peking University People's Hospital,recruited 200 patients with septic shock between January 2023 and August 2023.These patients were divided into survival(n=84)and death(n=116)groups based on 28-day outcomes.Clinical evaluations included laboratory tests and clinical scores,with lactate and PPI values assessed upon admission to the emergency room and at 6 h and 12 h after admission.Risk factors associated with mortality were analyzed using univariate and multivariate Cox regression analyses.Receiver operator characteristic(ROC)curve was used to assess predictive performance.Mortality rates were compared,and Kaplan-Meier survival plots were created.RESULTS:Compared to the survival group,patients in the death group were older and had more severe liver damage and coagulation dysfunction,necessitating higher norepinephrine doses and increased fl uid replacement.Higher lactate levels and lower PPI levels at 0 h,6 h,and 12 h were observed in the death group.Multivariate Cox regression identifi ed prolonged prothrombin time(PT),decreased 6-h PPI and 12-h PPI as independent risk factors for death.The area under the curves for 6-h PPI and 12-h PPI were 0.802(95%CI 0.742-0.863,P<0.001)and 0.945(95%CI 0.915-0.974,P<0.001),respectively,which were superior to Glasgow Coma Scale(GCS),Sequential Organ Failure Assessment(SOFA)scores(0.864 and 0.928).Cumulative mortality in the low PPI groups at 6 h and 12 h was signifi cantly higher than in the high PPI groups(6-h PPI:77.52%vs.22.54%;12-h PPI:92.04%vs.13.79%,P<0.001).CONCLUSION:PPI may have value in predicting 28-day mortality in patients with septic shock.

阿帕替尼对肺癌细胞侵袭迁移的影响及其作用机制

背景与目的肺癌是世界上对人类健康产生重大危害的癌症之一,近年来靶向治疗的效果日益显著。阿帕替尼(Apatinib, YN968D1)是目前研究较热的多靶点抗肿瘤药物,本研究旨在探讨Apatinib对肺癌细胞生物学特性的影响和其可能的作用机制。方法体外培养肺腺癌细胞株H1299与H3255,CCK法、划痕实验及Transwell实验检测Apatinib对H1299与H3255细胞增殖、迁移及侵袭的影响,Western blot检测肿瘤血管生成和侵袭相关蛋白的表达。结果Apatinib显著抑制H1299与H3255的增殖、迁移及侵袭能力,并呈浓度依赖性。Western blot显示,随药物浓度增加,VEGF、VEGFR2、N-cadherin、MMP9、MMP2、Vimentin表达下调,E-cadherin表达上调。结论 Apatinib可抑制肺腺癌细胞H1299、H3255的侵袭迁移能力,其机制可能通过调控上皮-间充质转化及基质金属蛋白酶相关蛋白的表达来实现。

基于TCGA数据库的中央型与周围型肺鳞癌基因表达差异性研究

背景与目的肺癌是一种具有高发病率与高死亡率的恶性肿瘤疾病,最常见的类型为非小细胞肺癌(non-small cell lung cancer, NSCLC),其中肺鳞癌作为NSCLC中的一个亚型,具有特殊的病理学类型及其特定的治疗方法,根据临床表型不同又可分为周围型和中央型。本研究基于中央型和周围型肺鳞癌的临床差异进一步探索其基因水平的差异和其潜在的价值。方法从癌症基因组图谱(The Cancer Genome Atlas, TCGA)数据库收集肺鳞癌数据集,下载临床信息资料及基因表达谱资料。整理资料,分析临床数据及相对应的基因信息。结果在临床特征分析中发现,中央型肺鳞癌较周围型肺鳞癌更容易发生淋巴结转移(46.2%, 67/145 vs 28.9%, 26/90; P=0.019),而在性别、年龄、肿瘤大小、有无远处转移、TNM分期、表皮生长因子受体(epidermal growth factor receptor, EGFR)突变等方面未见明显差异。在基因表达水平分析中发现,中央型与周围型肺鳞癌具有1,031个差异表达基因,其中,周围型与中央型相比,629个基因表达水平上调,402个基因表达水平下调。进一步富集分析显示差异表达基因主要体现在6个信号通路中,其中,刺激神经组织的配体-受体相互作用(neuroactive ligand-receptor interaction)通路是差异表达基因主要富集通路,其他差异表达基因主要与脂类代谢和糖代谢有关。相互作用网络分析显示,在表达上调差异基因中,肝细胞核因子1同源体A(hepatocyte nuclear factor 1 homeobox A, HNF1A)和细胞色素P450家族里的A亚家族发现的第四种酶(cytochrome p450 family, Cytochrome P450 3A4, CYP3A4)影响较为广泛,在表达下调差异基因中,人血清白蛋白(Albumin, ALB)与载脂蛋白A1(Apolipoprotein, APOA1)位于该作用网络的关键位置。结论中央型和周围型肺鳞癌患者不仅在淋巴结转移发生率上存在临床特征的差异,而且在基因表达水平亦有明显的不同。其中,HNF1A、CYP3A4、ALB、APOA1位于差异基因相互作用网络的关键位置,有可能参与调控二者的差异表型(phenotypic difference)。

miR-451通过靶向ROCK1对卵巢癌细胞侵袭和迁移能力的调控作用

目的:探讨miR-451对卵巢癌细胞侵袭和迁移能力的作用及机制。方法:通过实时荧光定量PCR(qPCR)检测卵巢癌组织及卵巢癌细胞、癌旁组织及正常卵巢上皮细胞中miR-451与Rho的卷曲螺旋激酶1(ROCK1)mRNA的表达;将卵巢癌CaOV-3细胞分为6组:Control组(未转染组)、miR-NC组(用miR-NC无序序列转染)、miR-451 mimic组(用过表达miR-451的模拟物转染)、miR-451 inhibitor组(用抑制miR-451表达的质粒转染)、pc-ROCK1组(用过表达ROCK1的质粒转染)和miR-451+pc-ROCK1组(miR-451的模拟物和过表达ROCK1的质粒联合转染);通过划痕实验检测细胞迁移能力;通过Transwell法检测细胞侵袭能力,通过蛋白印迹法检测E-钙粘附蛋白(E-carderin)、N-钙粘附蛋白(N-carderin)、细胞基质金属蛋白酶2(MMP2)、ROCK1蛋白表达水平;通过TargetScan数据库预测miR-451靶基因;通过双荧光素酶报告检测miR-451与ROCK1靶向关系。结果:与癌旁组织相比,在大多数卵巢组织中miR-451表达下调(57/70,81.43%);低表达的miR-451患者卵巢癌肿瘤较大,分化程度较差,多属于FIGO晚期,并存在明显的腹膜转移(P<0.05)。与对照组相比,miR-451 mimic组卵巢癌CaOV-3细胞划痕闭合率明显降低、侵袭细胞数目明显减少、E-cadherin明显上调、N-cadherin和MMP2表达明显下调(P<0.01),miR-451 inhibitor组和卵巢癌CaOV-3细胞划痕闭合率明显升高、侵袭细胞数目明显增多、E-cadherin明显下调、N-cadherin和MMP2表达明显上调(P<0.01)。miR-451靶向下调ROCK1。共转染pc-ROCK1逆转miR-451 mimic对卵巢癌CaOV-3细胞侵袭和迁移的影响(P<0.01)。结论:miR-451通过靶向下调RCOK1抑制卵巢癌CaOV-3细胞迁移和侵袭能力。

LC-3和P62在非小细胞肺癌中的表达及其临床特征分析

背景与目的 LC-3和P62是参与自噬过程的两个重要蛋白,在许多恶性肿瘤中高表达并与预后有关。本研究的目的在于探讨自噬标记物LC-3、P62蛋白在非小细胞肺癌中的表达及其临床特征。方法应用免疫组化法检测66例非小细胞肺癌患者肿瘤组织中LC-3和P62的表达情况,分析其表达状态与临床特征的关系。结果 LC-3在非小细胞肺癌组织中阳性表达率为40.9%(27/66),P62在非小细胞肺癌组织中阳性表达率为65.2%(43/66)。LC-3的阳性表达与患者的病理类型及转移情况明显相关(P<0.05);而P62的阳性表达与患者的病理类型,临床分期及淋巴结转移明显相关(P<0.05)。LC-3和P62的阳性表达与患者的性别、年龄和吸烟史无明显相关性(P>0.05)。LC-3与P62在非小细胞肺癌组织中的表达呈负相关性(rs=-0.0 6 5,P<0.0 0 1)。K a p l a n-M e i e r分析显示L C-3蛋白阳性表达的患者5年生存率明显高于阴性表达的患者(P<0.05),而P62蛋白的阳性表达确与患者的生存率无显著相关性。结论 LC-3和P62在非小细胞肺癌组织中呈现异常表达,提示自噬参与了非小细胞肺癌的发生及发展过程。

EZH2抑制剂与吉非替尼联合应用在EGFR-TKIs耐药肺癌细胞中的作用研究

背景与目的肺癌是危害身体健康的常见恶性肿瘤之一。随着表观遗传学的发展,研究者发现Zeste基因增强子同源物基因2(enhancer of Zeste homolog 2, EZH2)在肺癌中高表达且其表达量与预后息息相关,与此同时EZH2抑制剂也被发现能够提升肿瘤细胞对多种抗肿瘤药物的敏感性。本研究的目的在于探讨EZH2抑制剂与吉非替尼(gefitinib)联合应用,对耐吉非替尼细胞的增殖、凋亡及迁移的影响。方法以PC9吉非替尼敏感细胞和PC9/AB2吉非替尼耐药细胞为研究对象,应用CCK-8及EdU实验检测联合用药对于细胞活性及增殖的影响;通过划痕及Transwell小室检测联合用药对于细胞迁移能力的影响;并应用流式细胞学检测联合用药对于细胞凋亡的影响;并通过Western blot观察联合用药对EZH2及表皮生长因子(epidermal growth factor receptor, EGFR)信号通路相关蛋白的作用。结果在吉非替尼耐药细胞PC9/AB2细胞中,联合EZH2抑制剂GSK343与吉非替尼能够显著抑制耐药细胞的活性,降低细胞的迁移能力并诱导耐药细胞的凋亡。同时,联合用药也能够显著抑制EZH2表达及EGFR蛋白的磷酸化。结论 EZH2抑制剂GSK343与吉非替尼联合应用能够克服PC9/AB2对吉非替尼的耐药作用,此研究也提示协同治疗在肺癌EGFR-TKIs耐药逆转中具有一定的作用。

2D Layered Double Hydroxide Nanosheets and Their Derivatives Toward E cient Oxygen Evolution Reaction

Layered double hydroxides(LDHs)have attracted tremendous research interest in widely spreading applications.Most notably,transition-metal-bearing LDHs are expected to serve as highly active electrocatalysts for oxygen evolution reaction(OER)due to their layered structure combined with versatile com-positions.Furthermore,reducing the thickness of platelet LDH crystals to nanometer or even molecular scale via cleavage or delamination provides an important clue to enhance the activity.In this review,recent progresses on rational design of LDH nanosheets are reviewed,including direct synthesis via traditional coprecipitation,homogeneous precipitation,and newly developed topochemical oxidation as well as chemical exfoliation of parent LDH crystals.In addition,diverse strategies are introduced to modulate their electrochemical activity by tuning the composition of host metal cations and intercalated counter-anions,and incorporating dopants,cavi-ties,and single atoms.In particular,hybridizing LDHs with conductive components or in situ growing them on conductive substrates to produce freestanding electrodes can further enhance their intrinsic catalytic activity.A brief discussion on future research directions and prospects is also summarized.

PD 0332991对人内皮细胞增殖和凋亡的作用

背景与目的肿瘤的血管生成(angiogenesis)是肿瘤发展中的一个重要过程。PD 0332991是一种细胞周期抑制剂,能特异性抑制CDK4/6的活性及细胞周期进展,在小鼠的移植瘤模型中,使用PD 0332991治疗的小鼠,其移植瘤中微血管生成明显减少、血管密度显著低于对照组,但其机理不明。本研究的目的在于探讨PD0332991对血管内皮细胞的作用及分子机理。方法采用EA.hy926血管内皮细胞作为研究模型。MTT法及EdU法检测PD 0332991对EA.hy926细胞活性和增殖能力的影响;划痕实验和transwell小室实验检测PD 0332991对内皮细胞迁移力的影响;流式细胞术检测PD 0332991对内皮细胞细胞周期及细胞凋亡的影响;Western blot检测PD 0332991对内皮细胞细胞周期相关蛋白表达的影响。结果 PD 0332991显著抑制EA.hy926内皮细胞的增殖、活性及迁移能力;使EA.hy926内皮细胞周期受阻滞并诱导其凋亡;抑制CDK4/6表达以及Rb的磷酸化,从而抑制内皮细胞细胞周期进展。结论 PD 0332991能抑制内皮细胞的增殖和活性,并诱导其凋亡。

赋能与共享:发展职业教育对推进共同富裕的作用机制研究

共同富裕是中国特色社会主义新时代发展的必然要求,职业教育则为推进共同富裕提供了人才和技能支撑。从理论层面分析发展职业教育对推进共同富裕的影响机制,构建多层次共同富裕指标评价体系,并基于2010-2019年省级面板数据进行实证分析。结果显示,发展职业教育可通过人力资本、产业结构以及乡村振兴等中介机制赋能经济增长,并有助于实现经济发展成果的共享,有效推进共同富裕,这一结果经过一系列检验是稳健的。同时,东部与中西部地区的中介机制作用存在明显差异。研究结果对于通过发展职业教育推进共同富裕具有理论和现实意义。

Revealing the illumination effect on the discharge products in high-performance Li-O_(2) batteries with heterostructured photocatalysts

Aprotic lithium–oxygen batteries(LOBs)have been recognized as novel energy storage devices for their outstanding specific energy density,while the large discharge/charge overpotential is a tough barrier to be overcome.Here,hetero-structured MoS_(2)/ZnIn_(2)S_(4) nanosheets have been prepared to capture visible light and the generated charge carriers are utilized for promoting both the oxygen reduction reaction and the oxygen evolution reaction.With the light illumination in the discharge process,the abundant photo-inspired electrons serve as the reaction sites to promote the reduction of O_(2) into LiO_(2) which is finally deposited as Li_(2)O_(2).On the contrary,the generated holes in the valence band can contribute to the low oxidization potential of Li_(2)O_(2) during the charge process.It delivers a low charge potential of 3.29 V,with an excellent resulting energy efficiency of 96.7%,much superior to that of 69.2%in the dark condition.It is noted that the involvement of photoelectrons has influenced the growth of Li_(2)O_(2) films on the MoS_(2)/ZnIn_(2)S_(4) nanosheets through the surface-adsorption pathway.The insights from the theoretical calculation confirm that the photoelectrons favor the absorption of LiO_(2) and the formation of the Li_(2)O_(2) film through the surface route.Therefore,this paper provides a deeper understanding of the mechanism of photoinspired charge carriers in LOBs and will enable further exploration of photo-involved energy storage systems.

A high-quality sponge gourd(Luffa cylindrica)genome

Sponge gourd(Luffa cylindrica)is an important cultivated vegetable and medicinal plant in the family Cucurbitaceae.In this study,a draft genome sequence of the sponge gourd inbred line P93075 was analyzed.Using Illumina,PacBio,and 10×Genomics sequencing techniques as well as new assembly techniques such as FALCON and chromatin interaction mapping(Hi-C),a chromosome-scale genome of approximately 656.19 Mb,with an N50 scaffold length of 48.76 Mb,was generated.From this assembly,25,508 protein-coding gene loci were identified,and 63.81%of the whole-genome consisted of transposable elements,which are major contributors to the expansion of the sponge gourd genome.According to a phylogenetic analysis of conserved genes,the sponge gourd lineage diverged from the bitter gourd lineage approximately 41.6 million years ago.Additionally,many genes that respond to biotic and abiotic stresses were found to be lineage specific or expanded in the sponge gourd genome,as demonstrated by the presence of 462 NBS-LRR genes,a much greater number than are found in the genomes of other cucurbit species;these results are consistent with the high stress resistance of sponge gourd.Collectively,our study provides insights into genome evolution and serves as a valuable reference for the genetic improvement of sponge gourd.

Effect of Sample Temperature on Radiation Characteristics of Nanosecond Laser-Induced Soil Plasma

An Nd:YAG single pulse nanosecond laser of 532 nm wavelength with an 8 ns pulse width was projected on the soil samples collected from the campus of Bengbu College under 1 standard atmospheric pressure. Laser-induced breakdown spectroscopy at different sample temperatures was achieved. The intensity and signal-to-noise ratio (SNR) changes of different characteristic spectral lines could be analyzed when the sample temperature changes.The evolution of plasma electron temperature and electron density with the sample temperature was analyzed through Boltzmann oblique line method and Stark broadening method.The cause of the radiation enhancement of laser-induced metal plasma was discussed. Experimental results demonstrated that the spectral intensity, SNR, the electron temperature and electron density of plasma are positively related to the sample temperature, and reach saturation at 100℃.

Biphasic modulation of chemerin peptide-induced calcium flux and ERK phosphorylation by amyloid beta peptide

OBJECTIVE The chemokine-like receptor 1(CMKLR1,Chem R23) is a functional receptor for chemerin,the chemerin-derived nonapeptide(C9),and the amyloid β peptide 1-42(Aβ_(42)).Because these peptides share little sequence homology,studies were conducted to investigate their pharmacological properties and regulation at CMKLR1.METHODS Cells expressing CMKLR1 were incubated with Aβ_(42) before stimulation with a strong agonist,the C9 peptide.Calcium mobilization,c AMP inhibition and MAP kinase activation were measured.Intramolecular FRET were determined using CMKLR1 constructs with an ECFP attached to the C-terminus and a Fl As H binding motif embedded in the first intracellular loop(IL1).RESULTS Binding of both Aβ_(42) and the C9 peptide induced CMKLR1 internalization,but only the Aβ_(42)-induced receptor internalization involved clathrin-coated pits.Likewise,Aβ_(42) but not C9 stimulated β-arrestin 2 translocation to plasma membranes.A robust Ca^(2+)flux was observed following C9 stimulation,whereas Aβ_(42) was ineffective even at micromolar concentrations.Despite its low potency in calcium mobilization assay,Aβ_(42) was able to alter C9-induced Ca^(2+) flux in dose-dependent manner:a potentiation effect at 100 pmol·L^(-1) of Aβ_(42) was followed by a suppression at 10 nmol·L^(-1) and further potentiation at 1 μmol·L^(-1).This unusual and biphasic modulatory effect was also seen in the C9-induced ERK phosphorylation but the dose curve was opposite to that of Ca^(2+) flux and c AMP inhibition,suggesting a reciprocal regulatory mechanism.Intramolecular FRET assay confirmed that Aβ_(42) modulates CMKLR1 rather than its downstream signaling pathways.CONCLUSION These findings suggest Aβ_(42) as an allosteric modulator that can both positively and negatively regulate the activation state of CMKLR1 in a manner that differs from existing allosteric modulatory mechanisms.

Functionally diverse ligands modulate different activation states of the formyl peptide receptor 2,a G protein-coupled receptor

OBJECTIVE To identify the mechanisms by which the formyl peptide receptor 2(FPR2)mediates both inflammatory and anti-inflammatory signaling in an agonist-dependent manner.METHODS Cells expressing FPR2 were incubated with weak agonists,Aβ42 and Ac2-26,before stimulation with a strong agonist,WKYMVm.Calcium mobilization,c AMP inhibition and MAP kinase activation were measured.Intramolecular FRET were determined using FPR2 constructs with an ECFP attached to the C-terminus and a Fl As H binding motif embedded in the first or third intracellular loop(IL1 or IL3,respectively).RESULTS Aβ42 did not induce significant Ca^(2+) mobilization,but positively modulated WKYMVm-induced Ca^(2+) mobilization and c AMP reduction in a dose-variable manner within a narrow range of ligand concentrations.Treating FPR2-expressing cells with Ac2-26,a peptide with anti-inflammatory activity,negatively modulated WKYMVm-induced Ca^(2+) mobilization and c AMP reduction.Intramolecular FRET assay showed that stimulation of the receptor constructs with Aβ42 brought the C-terminal domain closer to IL1 but away from IL3.An opposite conformational change was induced by Ac2-26.The FPR2 conformation induced by Aβ42 corresponded to enhanced ERK phosphorylation and attenuated p38 MAPK phosphorylation,whereas Ac2-26 induced FPR2 conformational change corresponding to elevated p38 MAPK phosphorylation and reduced ERK phosphorylation.CONCLUSION Aβ42 and Ac2-26 induce different conformational changes in FPR2.These findings provide a structural basis for FPR2 mediation of inflammatory vs anti-inflammatory functions and identify a type of receptor modulation that differs from the classic positive and negative allosteric modulation.

Deep Learning-Based Invalid Point Removal Method for Fringe Projection Profilomet y

Fringe projection profilometry(FPP)has been widely applied to non-contact three-dimensional measurement in industries owing to its high accuracy and speed.The point cloud,which is a measurement result of the FPP system,typically contains a large number of invalid points caused by the background,ambient light,shadows,and object edge regions.Research on noisy point detection and elimination has been conducted over the past two decades.However,existing invalid point removal methods are based on image intensity analysis and are only applicable to simple measurement backgrounds that are purely dark.In this paper,we propose a novel invalid point removal framework that consists of two aspects:(1)A convolutional neural network(CNN)is designed to segment the foreground from the background of different intensity conditions in FPP measurement circumstances to remove background points and the most discrete points in background regions.(2)A two-step method based on the fringe image intensity threshold and a bilateral filter is proposed to eliminate the small number of discrete points remaining after background segmentation caused by shadows and edge areas on objects.Experimental results verify that the proposed framework(1)can remove background points intelligently and accurately in different types of complex circumstances,and(2)performs excellently in discrete point detection from object regions.

Martensitic transformation,shape memory effect and superelasticity of Ti-xZr-(30-x)Nb-4Ta alloys

Martensitic transformations,mechanical properties,shape memory effect and superelasticity of Ti-xZr-(30-x)Nb-4Ta(x=15,16,17 and 18;at%) alloys were investigated.X-ray diffraction(XRD),optical microscopy(OM) and transmission electron microscopy(TEM) results indicated that the Ti-16Zr-14Nb-4Ta,Ti-17Zr-13Nb-4Ta and Ti-18Zr-12Nb4Ta alloys were mainly composed of α″-martensite,while the Ti-15Zr-15Nb-4Ta alloy was characterized by predominant p phase.The reverse martensitic transformation temperatures increased when Nb was replaced by Zr,indicating stronger p-stabilizing effect for the former.The Ti-15Zr-15Nb-4Ta alloy displayed superelasticity during tensile deformation with a recovery strain of 3.51%.For the other three alloys with higher Zr content,the martensitic reorientation occurred during tensile deformation,resulting in shape memory recovery upon subsequent heating.The maximum shape memory effect was 3.46% in the Ti-18Zr-12Nb-4Ta alloy.

Review of research on loosening of threaded fasteners

Loosening of threaded fasteners is a key failure mode,which is mainly caused by the slippage and friction behaviors on the thread and bearing surfaces,and will affect the integrity and reliability of products.Numerous scholars have conducted research on the loosening of threaded fasteners;however,comprehensive reviews on the loosening of threaded fasteners have been scarce.In this review article,we define loosening as a loss of preload and divide it into non-rotational and rotational loosening.The causes and mechanisms of non-rotational and rotational loosening are summarised.Some essential topics regarding loosening under transverse vibration have also attracted significant attention and have been investigated widely,including the loosening curve,critical condition of loosening,and influencing factors of loosening.The research carried out on these three topics is also summarised in this review.It is believed that our work will not only help new researchers quickly understand the state-of-the-art research on loosening,but also increase the knowledge of engineers on this critical subject.In the future,it is important to conduct more quantitative research on local slippage accumulation,and the relationship between local slippage accumulation and rotational loosening,which will have the potential to comprehensively unravel the loosening mechanism,and effectively guide the anti-loosening design of threaded fasteners.

Regulating surface state of WO3 nanosheets by gamma irradiation for suppressing hydrogen evolution reaction in electrochemical N2 fixation

Realizing the reduction of N2 to NH3 at low temperature and pressure is always the unremitting pursuit of scientists and then electrochemical nitrogen reduction reaction offers an intriguing alternative.Here,we develop a feasible way,gamma irradiation,for constructing defective structure on the surface of WO3 nanosheets,which is clearly observed at the atomic scale by high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM).The abundant oxygen vacancies ensure WO3 nanosheets with a Faradaic efficiency of 23%at−0.3 V vs.RHE.Moreover,we start from the regulation of the surface state to suppress proton availability towards hydrogen evolution reaction(HER)on the active site and thus boost the selectivity of nitrogen reduction.

Single atom site conjugated copper polyphthalocyanine assisted carbon nanotubes as cathode for reversible Li-CO_(2) batteries

Recently,Li-CO_(2) battery has gradually become a research hotspot due to its high discharge capacity,energy density and environmental benefits.However,it has been an important problem for researchers because of its slow decomposition kinetics and difficult to generalize to practical application.Herein,we prepared copper polyphthalocyanine-carbon nanotubes composites(CuPPc-CNTs)by solvothermal in-situ polymerization of copper phthalocyanine on the surface of carbon nanotubes as cathode for reversible Li-CO_(2) batteries,which exhibits a high discharge capacity of 18,652.7 mAh·g^(-1) at current density of 100 mA·g^(-1),1.64 V polarization at 1,000 mA·g^(-1),and a stable cycles number of 160 is close to 1,630 h of charge-discharge process at 200 mA·g^(-1).Copper polyphthalocyanine has highly efficient copper single-atom catalytic sites with excellent CO_(2) adsorption and activation,while carbon nanotubes provide a conductive network.The synergistic effect of the two compounds enables it to have excellent catalytic activity.The density functional theory(DFT)calculation proved that the addition of copper polyphthalocyanine significantly improved the CO_(2) adsorption and activation process.This study provides an opportunity for the research of covalent organic polymers(COPs)single-atom catalyst in Li-CO_(2) battery field.