Recent progress on two-dimensional ferroelectrics:Material systems and device applications

Ferroelectrics are a type of material with a polar structure and their polarization direction can be inverted reversibly by applying an electric field.They have attracted tremendous attention for their extensive applications in non-volatile memory,sensors and neuromorphic computing.However,conventional ferroelectric materials face insulating and interfacial issues in the commercialization process.In contrast,two-dimensional(2D)ferroelectric materials usually have excellent semiconductor performance,clean van der Waals interfaces and robust ferroelectric order in atom-thick layers,and hold greater promise for constructing multifunctional ferroelectric optoelectronic devices and nondestructive ultra-high-density memory.Recently,2D ferroelectrics have obtained impressive breakthroughs,showing overwhelming superiority.Herein,firstly,the progress of experimental research on 2D ferroelectric materials is reviewed.Then,the preparation of 2D ferroelectric devices and their applications are discussed.Finally,the future development trend of 2D ferroelectrics is looked at.

The Causes and Applications of Code Switching Between Chinese and English in Social Intercourse

This paper examines the phenomenon of code switching between Chinese and English in China.It explores the causes,types,and applications of code switching,as well as the public’s attitudes towards it.The paper distinguishes between pathological and non-pathological code switching,and analyzes the corpus of code switching in Hong Kong.It also discusses how English as a dominant language affects the perception and use of code switching.The paper suggests that code switching is not only a linguistic but also an emotional process,and that speakers and listeners should be aware of their audience group when using code switching.

Two-Dimensional Metal-Halide Perovskite-based Optoelectronics: Synthesis, Structure, Properties and Applications

In the past decade, metal-halide perovskites have attracted increasing attention in optoelectronics, due to their superior optoelectronic properties.However, inherent instabilities of conventional three-dimensional(3D)perovskites over moisture, heat, and light remain a severe challenge before the realization of commercial application of metal-halide perovskites.Interestingly, when the dimensions of metal-halide perovskites are reduced to two dimensions(2D), many of the novel properties will arise, such as enlarged bandgap, high photoluminescence quantum yield, and large exciton binding energy. As a result, 2D metal-halide perovskite-based optoelectronic devices display excellent performance, particularly as ambient stable solar cells with excellent power conversion efficiency(PCE), high-performance light-emitting diodes(LEDs) with sharp emission peak, and high-sensitive photodetectors. In this review, we first introduce the synthesis, structure,and physical properties of 2D perovskites. Then, the 2D perovskite-based solar cells, LEDs, and photodetectors are discussed. Finally, a brief overview of the opportunities and challenges for 2D perovskite optoelectronics is presented.

Two-Dimensional Terahertz Time-Domain Spectroscopy and Its Applications

In this work, we review the developing progress of two-dimensional terahertz time-domain spectroscopy（THz-TDS） and its diverse applications, including analyzing the polarization of THz radiation from a laser-induced plasma source and studying the corresponding physical mechanism, and characterizing the optical properties of crystals, etc.

Pseudohalide induced tunable electronic and excitonic properties in two-dimensional single-layer perovskite for photovoltaics and photoelectronic applications

Two-dimensional(2D) layered organic-inorganic hybrid perovskites have attracted much more attention for some applications than their three-dimensional(3D) perovskite counterparts due to their promising thermal and moisture stabilities.In particular, the 2D perovskite devices have shown better promise for optoelectronic applications.However, tunability of optoelectronic properties is often demanded to improve the device performance.Herein, we adopt a newly method to tune the electronic properties of 2D perovskite by introducing pseudohalide into the structure.In this work, we designed a pseudohalidesubstituted 2D perovskite by substituting the out-of-plane halide with pseudohalide and studied the electronic and excitonic properties of 2D-BA2MX4 and 2D-BA2MX2Ps2(M=Ge^(2+), Sn^(2+), and Pb^(2+);X=I;Ps=NCO, NCS, OCN, SCN, Se CN).We revealed the dependence of electronic properties including band gaps, composition of band edges, bonding characteristics, work functions, effective masses, and exciton binding energies on different pseudohalides substituted in 2D perovskite.Our results indicate that the substitution of pseudohalide in 2D perovskites is energetically favorable and can significantly affect the bonding characteristics as well as the CBM and VBM that often play major role in determining their performance in optoelectronic devices.It is expected that the pseudohalide substitution will be helpful in developing more advanced optoelectronic device based on 2D perovskite by optimizing band alignment and promoting charge extraction.

Applications of genetic code expansion technology in eukaryotes

Unnatural amino acids(UAAs)have gained significant attention in protein engineering and drug development owing to their ability to introduce new chemical functionalities to proteins.In eukaryotes,genetic code expansion(GCE)enables the incorporation of UAAs and facilitates posttranscriptional modification(PTM),which is not feasible in prokaryotic systems.GCE is also a powerful tool for cell or animal imaging,the monitoring of protein interactions in target cells,drug development,and switch regulation.Therefore,there is keen interest in utilizing GCE in eukaryotic systems.This review provides an overview of the application of GCE in eukaryotic systems and discusses current challenges that need to be addressed.

Maximum two-dimensional (u×v,4,1,3)-OOCs

Let Ф（u ×v, k, Aa, Ac） be the largest possible number of codewords among all two- dimensional （u ×v, k, λa, λc） optical orthogonal codes. A 2-D （u× v, k, λa, λ）-OOC with Ф（u× v, k, λa, λc） codewords is said to be maximum. In this paper, the number of codewords of a maximum 2-D （u × v, 4, 1, 3）-OOC has been determined.

High-throughput computational material screening of the cycloalkane-based two-dimensional Dion–Jacobson halide perovskites for optoelectronics

Two-dimensional(2D) layered perovskites have emerged as potential alternates to traditional three-dimensional(3D)analogs to solve the stability issue of perovskite solar cells. In recent years, many efforts have been spent on manipulating the interlayer organic spacing cation to improve the photovoltaic properties of Dion–Jacobson(DJ) perovskites. In this work, a serious of cycloalkane(CA) molecules were selected as the organic spacing cation in 2D DJ perovskites, which can widely manipulate the optoelectronic properties of the DJ perovskites. The underlying relationship between the CA interlayer molecules and the crystal structures, thermodynamic stabilities, and electronic properties of 58 DJ perovskites has been investigated by using automatic high-throughput workflow cooperated with density-functional(DFT) calculations.We found that these CA-based DJ perovskites are all thermodynamic stable. The sizes of the cycloalkane molecules can influence the degree of inorganic framework distortion and further tune the bandgaps with a wide range of 0.9–2.1 eV.These findings indicate the cycloalkane molecules are suitable as spacing cation in 2D DJ perovskites and provide a useful guidance in designing novel 2D DJ perovskites for optoelectronic applications.

Applications of Low-Emissivity Hybrid Insulation in South Korea

Low-Emissivity Hybrid Insulation has been developed in South Korea. It combines both resistive and reflective insulating principle. It is composed with many layers of reflective aluminum foils and honeycomb-structure air cells with polyethylene foam. This paper introduces recent South Korean building insulation code and the applications of Low-Emissivity Hybrid Insulation to meet the code.

An Empirical Analysis of the Impact of the Contract Book of the Civil Code on Labor Dispute Trial Practices:A Study of Four Hundred Judgments

Interpretation(I)of the Supreme People’s Court of Issues Concerning the Application of Law in the Trial of Labor Dispute Cases allows for the application of pertinent laws and regulations,including the Civil Code of the People’s Republic of China(hereinafter referred to as the“Civil Code”),in labor dispute cases.This has resolved the controversy over the relationship between civil law and labor law in academic and practical communities.In view of this development,we examined four hundred judicial documents,analyzing the focal points of disputes,the reasoning behind judgments,applicable laws,and judgment results.Our study identified seven impacts of the Contract Book of the Civil Code on labor dispute trial practices,exploring the underlying logic behind these changes and proposing policy suggestions to promote consistent judgments across jurisdictions,enhance judicial credibility,and encourage employers to govern enterprises in compliance with the law while empowering employees to safeguard their rights in accordance with relevant laws and regulations.

外泌体来源非编码RNA对骨关节炎微环境的作用及临床应用进展

背景:骨关节炎是一种常见的关节退行性疾病,其发生发展的病因学机制尚不清楚。早期骨关节炎的及时诊治十分重要,目前尚无确切有效的方法。外泌体来源广泛,其中包含非编码RNA(Non-coding RNAs,ncRNAs),如微小RNAs、环状RNAs和长链非编码RNAs。外泌体ncRNAs可直接从原始细胞递送至邻近或远程细胞,通过细胞间通讯调节细胞活性,在重塑骨关节微环境中具有重要的调控作用。目的:总结外泌体来源ncRNAs对骨关节炎关节内微环境的干预作用,以及在临床应用中取得的进展,阐明其在骨关节炎诊治方面的潜力。方法:以“exosomes,non-coding RNA,osteoarthritis,application,signal pathway,synovial fluid,cartilage cells,cartilage matrix,subchondral bone,mechanism”为检索词在PubMed数据库中进行检索,最终纳入66篇相关文献进行综述分析。结果与结论:①外泌体来源ncRNAs在骨关节炎的发病过程中对关节内微环境具有重要调控作用,主要体现在外泌体ncRNAs调控关节内炎症反应、软骨细胞及软骨基质的退化,软骨下骨重塑和细胞间通讯。②外泌体中的ncRNAs可以作为骨关节炎的生物标志物,帮助骨关节炎的早期诊断和监测疾病进展与预后。③外泌体ncRNAs可作为骨关节炎的治疗靶点,外泌体携带miRNAs递送到关节的软骨细胞及软骨基质,发挥调控作用。④外泌体ncRNAs可以通过调控基因表达、促进细胞间通讯,提高软骨组织工程的效果,修复或再生受损软骨。⑤未来研究者应继续发掘外泌体来源ncRNAs对骨关节炎的干预机制,并可结合最新软骨组织工程的研究成果应用到临床之中,这将有效帮助解决骨关节炎患者的病痛。

一种基于边界斜率拟合的角点检测方法

图像中的角点为描述物体特征提供关键信息,是复杂应用(如图像分类、目标检测和跟踪、定位和测量)的预处理步骤,角点检测的质量将直接影响后续图像处理的有效性.在工业环境中,角点检测算法需要在各类噪声和干扰因素下,对大规模数据集进行高效处理,以实现实时和准确的角点检测.因此,研究和设计快速高效、高准确性的角点检测算法具有重要意义.针对传统算法需要进行曲率计算或曲线拟合的局限性,提出了一种基于Freeman边界链码的快速、轻量级角点检测算法,通过对Freeman链码在角点之前和之后的连续多个点进行线段的斜率拟合和夹角的阈值判定,进而识别出角点.从准确性、鲁棒性和计算速度等方面,在NRS工业图像集上与主流角点检测算法进行了对比实验.结果表明,所提出的算法具有较少漏检和误检的角点数量,并实现了更快的检测速度,在工业应用中更具有优势.

“自甘风险”规则在学校体育活动中的司法实践

本文以案例为切入点,将民法典“自甘风险”规则在学校体育活动中的适用条件进行了解读。通过文中的案例得出适用“自甘风险”规则的构成要件有四个,缺一不可。

法治政府建设中民法典适用研究

民法典以其基本法律的属性对我国法治政府建设起着规范作用。法治政府在内涵建设上需要秉持人民至上的价值理念、权利保障的基本要求、依法行政的运行规则、公私协同的治理模式。民法典是法治政府建设的基本法律依据,是正确处理政府与市场、公法与私法的关系的标尺。它强化了法治政府建设的价值目标,推动着良法善治的政府治理实现。当前,法治政府建设对民法典的适用需要进一步解决民事主体权利保护,公权与私权、政府与市场的协调融合,以及社会公序良俗维护等方面的问题。因此,法治政府建设需要以继续完善立法、规范行政行为、遵从民法优先的冲突解决机制等方面作为民法典适用的关键。

论清偿型以物抵债协议产生的选择权——以《合同编通则解释》第27条为中心

《合同编通则解释》第27条规定的“债务履行期限届满后所达成的以物抵债协议”属于“清偿型以物抵债协议”。该条在总结司法实践经验的基础上,围绕对债权人的保护,将以物抵债协议规定为诺成合同,确立了清偿型以物抵债协议生效后新旧债并存的规则。在解释当事人之间达成的以物抵债协议时,应当采取两步走的方式:第一步是确定当事人是否有以新债代替旧债的合意,第二步是在不能确定合同发生变更时,出现新旧债并存的局面。在新旧债并存时,该条并未明确债务人的选择权,但该条规定与民法典第515条选择之债的规定是一致的,该条规定内容可以解释为在新旧债并存时,债务人享有选择权。同时,该条也确认了,在债务人不履行新债务时债权人的选择规则,并与民法典第515条规定保持了一致。债务人不履行新债时债权人有选择权。债权人一旦行使选择权,债务人就应当履行相应的债务。通过选择权的行使将使选择之债变成简单之债。

长链非编码RNA与牙周炎

背景:近年来,大量研究显示长链非编码RNA(long non-coding RNA,lnc RNA)在牙周炎的发病过程有重要作用,包括免疫反应过程及细胞(牙周膜干细胞、破骨细胞)的生物活性和功能,人们试图通过调控lnc RNA表达水平来实现对牙周炎症的调控及牙周组织的再生。目的:就lnc RNA在牙周炎中的研究进展进行综述,以期望更好地推进lnc RNA在牙周炎的研究。方法:第一作者检索Pub Med、中国知网等数据库建库到2023年3月发表的相关文献,以“长链非编码RNA,lnc RNA,牙周炎,牙周,免疫,炎症,牙周膜干细胞,破骨细胞,成骨分化,骨吸收,骨形成,复发,缺氧,氧化应激,静态机械应变”为中文检索词;“lnc RNA,periodontitis,periodontal,immunity,inflammation,periodontalmembranestemcells,osteoclasts,osteogenicdifferentiation,bone resorption,bone formation,recurrence,hypoxia,oxidative stress,static mechanical strain”为英文检索词,阅读每篇文献的文题、摘要进行初筛,最终筛选出87篇文献进行归纳分析。结果与结论:(1)牙周致病菌刺激机体导致免疫效应失衡引发炎症反应造成牙周组织的破坏,lnc RNA参与其调控机制。(2)lnc RNA对炎性环境的牙周膜细胞主要参与了促炎的调控,对于破骨细胞分化的影响,通过ce RNA机制进行调控,为探究牙周炎发病机制提供了新的线索。对于B细胞及巨噬细胞,lnc RNA在牙周炎中可调控其亚群的浸润、细胞活性和功能发挥。(3)lnc RNA参与牙周炎相关免疫反应主要在Toll样受体与NOD样受体两种模式识别受体与核因子κB途径这一信号通路发挥作用。(4)探究lnc RNA是否可作为牙周炎生物学标志在牙周炎的诊断及预后复发问题上有很大价值。(5)已有动物实验证实了可以通过调控lnc RNA的表达水平来逆转lnc RNA在牙周炎的作用从而起到抗炎作用,其对牙周炎的免疫治疗研究有很大价值。(6)Lnc RNA对于牙周膜干细胞的调控主要通过内源性竞争机制及各种信号通路实现,且其作用受多种因素影响,如炎性环境、机械应变及缺氧和氧化应激等,通过这些相关因素进行相关机制的研究为牙周炎的治疗提供了新的思路。

知识产权惩罚性赔偿的司法适用困境及其化解

《民法典》中知识产权惩罚性赔偿总括性条款的增设,标志着我国知识产权惩罚性赔偿体系的建立。最高人民法院发布的《最高人民法院关于审理侵害知识产权民事案件适用惩罚性赔偿的解释》进一步细化了知识产权惩罚性赔偿制度的具体适用,为司法实践提供了更加明确的指引。然而,该制度的实际司法运行却面临着主观要件不统一且常与客观要件的判定相重叠、惩罚性赔偿同法定赔偿关系不明、倍数计算出现分歧等多重适用困境。全面解读“故意”与“情节严重”的具体内涵与认定因素,使法定赔偿重回补偿性赔偿之本位,重塑倍比系数之立法区间,才能更好地适用知识产权惩罚性赔偿制度。

非能动安全壳冷却系统空气混合对流换热试验研究

为论证大型非能动核电厂空气导流板优化方案的可行性,搭建了安全壳冷却能力验证试验台架(COCOVET)。本文选取COCOVET空气冷却试验工况,采用粒子图像测速(PIV)手段将非能动安全壳冷却系统(PCS)环腔的空气流动可视化,通过对比试验数据和程序模拟结果,研究PCS环腔空气强迫对流和自然对流并存的混合对流换热现象,论证导流板优化方案可行性。研究结果表明:PCS环腔下降段空气到达导流板尾部区域后,大部分空气折流180°进入上升段,沿导流板向上流动,少量空气沿冷却面继续向下流动。在无导流板区域,加热面传热方式以偏自然对流类型为主,加热面热流密度沿高度方向基本不变。在有导流板区域,PCS环腔上升段存在明显的入口效应,加热面热流密度呈现迅速增加后降低的趋势。安全壳安全分析程序计算值和试验值符合良好,适用于模拟空气混合对流换热过程。研究结果验证了大型非能动核电厂导流板优化方案可行性,也丰富了空气混合对流换热研究内容。

基于视觉增强的桥梁检测算法及技术

为了识别桥梁结构微小振动,提出一种基于方向码匹配(OCM)法的靶标圆心检测算法.该算法首先采用OCM法实现像素级匹配,然后在最佳匹配区域采用靶标圆心检测算法进行精确跟踪.通过室内试验,将基于OCM的靶标圆心检测算法与基于相位的光流法和OCM亚像素实现算法进行对比,研究3种算法在不同振动幅度和实际工程应用的适用性,为实桥检测提供技术方案比选依据.结果表明:所提算法在各种振动幅度下均能精确地识别结构振动位移和频率,在实桥应用时应考虑靶标粘贴的可行性;基于相位的光流法在幅度指标小于2 mm或1.7像素的微小振动工况下能精确地识别结构的振动位移和频率;OCM亚像素实现算法的分辨精度取决于插值点的数量,对大幅度振动工况的识别具有与所提算法相似的效果.

非编码RNA与间充质干细胞研究的相关计量学分析

背景:非编码RNA作为一类不编码蛋白质的RNA分子,在细胞调控中发挥关键作用。同时,间充质干细胞具有多向分化潜能,对组织修复和再生至关重要。近年来,研究者们对非编码RNA在调控间充质干细胞功能中的作用展开了深入探讨。目的:通过文献计量学分析方法系统地了解非编码RNA与间充质干细胞相关研究的发展趋势与关键领域。方法:从Web of Science核心合集1990年至今的科学引文索引扩展获取非编码RNA与间充质干细胞相关研究的文献数据,运用VOSviewer和Cite Space计量学软件对年份、国家或地区、研究机构、被引文献和关键词进行发文量、聚类、被引频次、突增性和中介中心性进行分析,揭示该研究领域的知识基础及前沿热点。结果与结论:(1)最终纳入5348篇文献,发表在1997-2021年,相关文献呈现明显的增长趋势,尽管在2022年略有减少,其发文量仍保持较高水平,中国在该领域的研究中占据主导地位,其中上海交通大学为最活跃的机构。(2)对被引文献分析发现,高突增性、高中介中心性、高被引的文献主要与微小RNA、细胞外囊泡和骨代谢等内容相关,这些文献构成了非编码RNA与间充质干细胞研究领域的重要知识基础。(3)对关键词进行突增性分析发现,至今保持高突增性的关键词包括外泌体、环状RNA、细胞外囊泡和损伤。(4)对关键词进行聚类演变分析,发文量仍保持增长趋势的关键词聚类包括:肿瘤微环境、骨关节炎、氧化应激和细胞外囊泡,这些关键词反映了目前以及未来该领域的研究热点。(5)文章结果不仅展示了非编码RNA与间充质干细胞研究领域的研究态势,更重要的是有望为研究人员提供潜在的方向和启示。