积“微”致著:2012—2022年城市微更新回顾与展望

随着城市的快速发展和大规模扩张,城市更新工作也相应进行转型。小尺度、精细化的微更新模式成为当前存量时代建筑改造、环境优化、设施完善、品质提升的重要方式。回顾城市微更新发展历程,总结各阶段的问题和经验,有助于把握微更新的内涵与外延。文章根据我国政策法规和城市发展进程,将2012—2022年的城市微更新发展划分为萌芽伊始、深化探索、多元发展3个阶段,并对各个阶段的现实背景、学术研究及实践活动进行分析,归纳总结各发展阶段的基本特征。最后基于城市微更新的发展轨迹,提出多样化、人本化、规范化及创新化的发展新趋势,为我国城市微更新的发展提供参考。

Accelerated Sequential Deposition Reaction via Crystal Orientation Engineering for Low-Temperature,High-Efficiency Carbon-Electrode CsPbBr_(3) Solar Cells

Low-temperature,ambient processing of high-quality CsPbBr_(3)films is demanded for scalable production of efficient,low-cost carbon-electrode perovskite solar cells(PSCs).Herein,we demonstrate a crystal orientation engineering strategy of PbBr_(2)precursor film to accelerate its reaction with CsBr precursor during two-step sequential deposition of CsPbBr_(3)films.Such a novel strategy is proceeded by adding CsBr species into PbBr_(2)precursor,which can tailor the preferred crystal orientation of PbBr_(2)film from[020]into[031],with CsBr additive staying in the film as CsPb_(2)Br_(5)phase.Theoretical calculations show that the reaction energy barrier of(031)planes of PbBr_(2)with CsBr is lower about 2.28 eV than that of(O2O)planes.Therefore,CsPbBr_(3)films with full coverage,high purity,high crystallinity,micro-sized grains can be obtained at a low temperature of 150℃.Carbon-electrode PSCs with these desired CsPbBr_(3)films yield the record-high efficiency of 10.27%coupled with excellent operation stability.Meanwhile,the 1 cm^(2)area one with the superior efficiency of 8.00%as well as the flexible one with the champion efficiency of 8.27%and excellent mechanical bending characteristics are also achieved.

3D DEM simulation of hard rock fracture in deep tunnel excavation induced by changes in principal stress magnitude and orientation

To achieve the loading of the stress path of hard rock,the spherical discrete element model(DEM)and the new flexible membrane technology were utilized to realize the transient loading of three principal stresses with arbitrary magnitudes and orientations.Furthermore,based on the deep tunnel of China Jinping Underground Laboratory II(CJPL-II),the deformation and fracture evolution characteristics of deep hard rock induced by excavation stress path were analyzed,and the mechanisms of transient loading-unloading and stress rotation-induced fractures were revealed from a mesoscopic perspective.The results indicated that the stressestrain curve exhibits different trends and degrees of sudden changes when subjected to transient changes in principal stress,accompanied by sudden changes in strain rate.Stress rotation induces spatially directional deformation,resulting in fractures of different degrees and orientations,and increasing the degree of deformation anisotropy.The correlation between the degree of induced fracture and the unloading magnitude of minimum principal stress,as well as its initial level is significant and positive.The process of mechanical response during transient unloading exhibits clear nonlinearity and directivity.After transient unloading,both the minimum principal stress and minimum principal strain rate decrease sharply and then tend to stabilize.This occurs from the edge to the interior and from the direction of the minimum principal stress to the direction of the maximum principal stress on theε1-ε3 plane.Transient unloading will induce a tensile stress wave.The ability to induce fractures due to changes in principal stress magnitude,orientation and rotation paths gradually increases.The analysis indicates a positive correlation between the abrupt change amplitude of strain rate and the maximum unloading magnitude,which is determined by the magnitude and rotation of principal stress.A high tensile strain rate is more likely to induce fractures under low minimum principal stress.

Effects of orientation on the fatigue crack growth behaviors of the ZK60 magnesium alloy in air and PBS

Strong anisotropic corrosion and mechanical properties caused by specimen orientations greatly limit the applications of wrought magnesium alloys.To investigate the influences of specimen orientation,the corrosion tests and(corrosion)fatigue crack growth tests were conducted.The rolled and transverse surfaces of the materials show distinct corrosion rate differences in the stable corrosion stage,but the truth is the opposite for the initial stage of corrosion.In air,specimen orientations have a significant influence on the plastic deformation mechanisms near the crack tip,which results in different fatigue fracture surfaces and cracking paths.Compared with R-T specimens,N-T specimens show a slower fatigue crack growth(FCG)rate in air,which can be attributed to crack closure effects and deformation twinning near the crack tip.The corrosion environment will not significantly change the main plastic deformation mechanisms for the same type of specimen.However,the FCG rate in phosphate buffer saline(PBS)is one order of magnitude higher than that in air,which is caused by the combined effects of hydrogen-induced cracking and anodic dissolution.Owing to the similar corrosion rates at crack tips,the specimens with different orientations display close FCG rates in PBS.

Evaluation of New Graduate Nursing Orientation Program

The study site is a holistic patient-centered organization that has developed a 16-week long orientation program for new graduate nurses entering the hospital setting. The purpose of the program is for new graduate nurses to gain the confidence, competence, and critical thinking skills for providing safe patient care. The issue occurring within the organization is that there is an increasing rise in the number of turnover rates of new graduates leaving the hospital, thus making evaluating the program a necessity to problem-solving. There has been no evaluation of the program in the past five years to reveal why the increase in the recent turnover rates. The data collected during the interview process was coded and categorized into three main sections: organizational, substantive, and theoretical. The evaluator used an organizational category to investigate for board areas or issues within the problem attempting to be solved. The evaluator concluded from the results and findings that the issue, a poor preceptor-preceptee relationship was seen by all stakeholders involved. The literature presented concludes that continuous evaluation of orientation programs is crucial for the professional and personal growth of new graduate nurses in the hospital.

Effects of mesoclimate and microclimate variations mediated by high altitude and row orientation on sucrose metabolism and anthocyanin synthesis in grape berries

Climate change and extreme weather pose significant challenges to the traditional viticulture regions.Emerging high-altitude grape-producing regions with diverse orientations have shown great potential in coping with this challenge.Stable,high-quality wine grape production may be achieved by synchronizing the meso-and microclimate.To clarify the role of high altitude and row orientation in meso-and microclimate and the response of berries to it,we evaluated seven years(2012-2018)of climate data,two years of basic grape(Cabernet Sauvignon,Vitis vinifera L.)quality,and one-year microclimate from veraison to harvest.By comparing two locations(Sidon 2047 m,Sinon 2208 m)in Yunnan Province,China,we found that the average temperature has been stable at approximately 15℃ for seven years,with no extreme weather or,noticeable global warming.The light intensity(LI)in the north-south(NS)was more balanced than the east-west(EW)direction,and the east-west to the south(EW-S)canopy side was almost higher than the other sides.High LI was associated with high photosynthetically active radiation(PAR),ultraviolet(UV),and infrared(IR)light and vice versa.The north-south to the east(NS-E)and east-west to the north(EWN)sides were characterized by lower LI and higher UV and IR light,and higher total anthocyanin content.Most anthocyanin synthesis-related genes,for example,VvF3'H and VvF3'5'H,were highly expressed in NS-E from veraison to maturity.Perhaps UV and IR light induced their expression.This study provides new insights on the role of differently orientated rows in controlling grape quality due to varied light quality.The findings are globally significant,particularly in the context of climate change,and offer fresh insights into berry physiological responses and decision-making for the management of existing vineyards.

Alleviating the anisotropic microstructural change and boosting the lithium ions diffusion by grain orientation regulation for Ni-rich cathode materials

Generally,layered Ni-rich cathode materials exhibit the morphology of polycrystalline secondary sphere composed of numerous primary particles.While the arrangement of primary particles plays a very important role in the properties of Ni-rich cathodes.The disordered particle arrangement is harmful to the cyclic performance and structural stability,yet the fundamental understanding of disordered structure on the structural degradation behavior is unclarified.Herein,we have designed three kinds of LiNi_(0.83)Co_(0.06)Mn_(0.11)O_(2) cathode materials with different primary particle orientations by regulating the precursor coprecipitation process.Combining finite element simulation and in-situ characterization,the Li^(+)transport and structure evolution behaviors of different materials are unraveled.Specifically,the smooth Li^(+)diffusion minimizes the reaction heterogeneity,homogenizes the phase transition within grains,and mitigates the anisotropic microstructural change,thereby modulating the crack evolution behavior.Meanwhile,the optimized structure evolution ensures radial tight junctions of the primary particles,enabling enhanced Li^(+)diffusion during dynamic processes.Closed-loop bidirectional enhancement mechanism becomes critical for grain orientation regulation to stabilize the cyclic performance.This precursor engineering with particle orientation regulation provides the useful guidance for the structural design and feature enhancement of Ni-rich layered cathodes.

Laser-Constructing 3D Copper Current Collector with Crystalline Orientation Selectivity for Stable Lithium Metal Batteries

The practical application of lithium(Li)metal anodes in high-capacity batteries is impeded by the formation of hazardous Li dendrites.To address this challenge,this research presents a novel methodology that combines laser ablation and heat treatment to precisely induce controlled grain growth within laser-structured grooves on copper(Cu)current collectors.Specifically,this approach enhances the prevalence of Cu(100)facets within the grooves,effectively lowering the overpotential for Li nucleation and promoting preferential Li deposition.Unlike approaches that modify the entire surface of collectors,our work focuses on selectively enhancing lithiophilicity within the grooves to mitigate the formation of Li dendrites and exhibit exceptional performance metrics.The half-cell with these collectors maintains a remarkable Coulombic efficiency of 97.42%over 350 cycles at 1 mA cm^(−2).The symmetric cell can cycle stably for 1600 h at 0.5 mA cm^(−2).Furthermore,when integrated with LiFePO4 cathodes,the full-cell configuration demonstrates outstanding capacity retention of 92.39%after 400 cycles at a 1C discharge rate.This study introduces a novel technique for fabricating selective lithiophilic three-dimensional(3D)Cu current collectors,thereby enhancing the performance of Li metal batteries.The insights gained from this approach hold promise for enhancing the performance of all laser-processed 3D Cu current collectors by enabling precise lithiophilic modifications within complex structures.

Synergistic effect of orientation and temperature on slip behavior and precipitation behavior of Al−Cu−Li single crystals

The slip behavior and precipitation behavior of four Al−Cu−Li single crystals with varying orientations at different temperatures were investigated using electron backscattering diffraction(EBSD)and transmission electron microscopy(TEM).The maximum differences in yield strength and ductility of the single crystals at room temperature are 41.6%and 14.7%,respectively.This indicates that the mechanical properties are strongly influenced by the crystal orientation.Moreover,grains with varying orientations exhibit distinct slip characteristics,including slip homogenization,slip localization,and multiple slip.In single crystal SC1,slip localization primarily contributes to its inferior ductility compared to other grains.Nevertheless,during deformation at 250℃,the distinct morphology and distribution of precipitates in the crystals are also correlated with orientation,which causes the increase in the maximum elongation difference to 20.8%in all selected single crystals.Notably,SC1,with a precipitate volume fraction of 2.65%,exhibits more severe slip localization compared to room temperature conditions,while SC2,with a precipitate volume fraction of 4.79%,demonstrates cross-slip characteristics,significantly enhancing the plastic deformation capacity of the Al−Cu−Li alloy.

An Expert System to Detect Political Arabic Articles Orientation Using CatBoost Classifier Boosted by Multi-Level Features

The number of blogs and other forms of opinionated online content has increased dramatically in recent years.Many fields,including academia and national security,place an emphasis on automated political article orientation detection.Political articles(especially in the Arab world)are different from other articles due to their subjectivity,in which the author’s beliefs and political affiliation might have a significant influence on a political article.With categories representing the main political ideologies,this problem may be thought of as a subset of the text categorization(classification).In general,the performance of machine learning models for text classification is sensitive to hyperparameter settings.Furthermore,the feature vector used to represent a document must capture,to some extent,the complex semantics of natural language.To this end,this paper presents an intelligent system to detect political Arabic article orientation that adapts the categorical boosting(CatBoost)method combined with a multi-level feature concept.Extracting features at multiple levels can enhance the model’s ability to discriminate between different classes or patterns.Each level may capture different aspects of the input data,contributing to a more comprehensive representation.CatBoost,a robust and efficient gradient-boosting algorithm,is utilized to effectively learn and predict the complex relationships between these features and the political orientation labels associated with the articles.A dataset of political Arabic texts collected from diverse sources,including postings and articles,is used to assess the suggested technique.Conservative,reform,and revolutionary are the three subcategories of these opinions.The results of this study demonstrate that compared to other frequently used machine learning models for text classification,the CatBoost method using multi-level features performs better with an accuracy of 98.14%.

Predicting Grain Orientations of 316 Stainless Steel Using Convolutional Neural Networks

This paper presents a deep learning Convolutional Neural Network(CNN)for predicting grain orientations from electron backscatter diffraction(EBSD)patterns.The proposed model consists of multiple neural network layers and has been trained on a dataset of EBSD patterns obtained from stainless steel 316(SS316).Grain orientation changes when considering the effects of temperature and strain rate on material deformation.The deep learning CNN predicts material orientation using the EBSD method to address this challenge.The accuracy of this approach is evaluated by comparing the predicted crystal orientation with the actual orientation under different conditions,using the Root-Mean-Square Error(RMSE)as the measure.Results show that changing the temperature causes different grain orientations to form,meeting the requirements.Further investigations were conducted to validate the results.

Nonlinear Time History Analysis for the Different Column Orientations under Seismic Wave Synthetic Approach

The significant impact of earthquakes on human lives and the built environment underscores the extensive human and economic losses caused by structural collapses. Over the years, researchers have focused on improving seismic design to mitigate earthquake-induced damages and enhance structural performance. In this study, a specific reinforced concrete (RC) frame structure at Kyungpook National University, designed for educational purposes, is analyzed as a representative case. Utilizing SAP 2000, the research conducts a nonlinear time history analysis to assess the structural performance under seismic conditions. The primary objective is to evaluate the influence of different column section designs, while maintaining identical column section areas, on structural behavior. The study employs two distinct seismic waves from Abeno (ABN) and Takatori (TKT) for the analysis, comparing the structural performance under varying seismic conditions. Key aspects examined include displacement, base shear force, base moment, joint radians, and layer displacement angle. This research is anticipated to serve as a valuable reference for seismic restraint reinforcement work on RC buildings, enriching the methods used for evaluating structures through nonlinear time history analysis based on the synthetic seismic wave approach.

Integrating Virtual Reality and Energy Analysis with BIM to Optimize Window-to-Wall Ratio and Building’s Orientation for Age-in-Place Design at the Conceptual Stage

This study unfolds an innovative approach aiming to address the critical role of building design in global energy consumption, focusing on optimizing the Window-to-Wall Ratio (WWR), since buildings account for approximately 30% of total energy consumed worldwide. The greatest contributors to energy expenditure in buildings are internal artificial lighting and heating and cooling systems. The WWR, determined by the proportion of the building’s glazed area to its wall area, is a significant factor influencing energy efficiency and minimizing energy load. This study introduces the development of a semi-automated computer model designed to offer a real-time, interactive simulation environment, fostering improving communication and engagement between designers and owners. The said model serves to optimize both the WWR and building orientation to align with occupants’ needs and expectations, subsequently reducing annual energy consumption and enhancing the overall building energy performance. The integrated model incorporates Building Information Modeling (BIM), Virtual Reality (VR), and Energy Analysis tools deployed at the conceptual design stage, allowing for the amalgamation of owners’ inputs in the design process and facilitating the creation of more realistic and effective design strategies.

中国文学史编纂中的“唱对台戏”

中国文学史编纂中的“唱对台戏”,包括多种类型,或发生在晚辈与前辈之间,如五四新文化人之于清民之际的文学史家;或发生在同辈学人之间,如五四时期的学衡派之于新文化人;或发生在域外汉学与本土学术之间,如《哥伦比亚中国文学史》之于通行的中国文学史。“唱对台戏”促进了对中国文学发展历程的深入理解,是中国文学史编纂逐渐趋于完善的必由之路。对其间的种种情形加以考察,有助于深入把握“先入之见”与“客观性”的辩证关系。

20世纪三四十年代马克思主义史家的新经世致用论——以马克思主义史学四大家为中心

20世纪三四十年代,中国马克思主义史学形成了一种新经世致用论。这种新经世致用论以马克思主义“科学性与革命性相统一”的原则为指导,是对传统经世致用论批判与继承的产物,具体表现为史学求真与致用的统一,体现了马克思主义的实践理性精神。马克思主义与中国传统文化都有实践理性精神,而传统经世致用思想则为马克思主义史家新经世致用论提供了历史解释的视域。马克思主义史家虽然认为革命性是以科学性为基础的,但往往为了革命性而忽视科学性。故史学要真正做到经世致用,必须以尊重史学科学性为前提。

对标“贸易面向型”国际数据规则提升自贸区(港)数据治理水平

内嵌于经贸协定或其他经贸安排中的“贸易面向型”数据规则备受关注。“贸易面向型”数据规则内容渐趋丰富,不仅包括跨境流动和存储等传统数据规则,还纳入了数据共享和数据创新等前沿数据规则。追求发展利益是各经济体制定“贸易面向型”数据规则的主要价值取向,同时也通过内设“安全阀”的方式兼顾安全利益,并将数据规则与其他规则融合。在此背景下,我国自贸区(港)需重点推进“流动+共享+创新”三位一体的数据治理框架,在国家法律法规授权范围内进行数据治理创新,同时关注数据治理与其他治理问题的内在协同。自贸区(港)可通过“提高数据跨境合规实操性,解决企业数据跨境合规痛难点”“强化数字基础设施建设,提升数据标准化及安全保障能力”“从确权、定价、交易规则等方面构建数据要素流通交易机制”“务实推进构建公共数据开放共享机制”等核心抓手提升数据治理水平。

轧辊用012Al钢热处理试验研究

研究了轧辊用012Al钢的热处理工艺及其对钢的显微组织、硬度及力学性能的影响,并对回火热稳定性进行了理论计算与分析。结果表明,012Al钢具有较强的淬硬能力,1 100℃油淬+540℃回火硬度可达60 HRC以上。012Al钢调质硬度为35 HRC时,屈服强度可达850 MPa,抗拉强度可达1 100 MPa;淬火硬度为59 HRC时,抗拉强度可达2 300 MPa,弯曲强度可达3 700 MPa。基于扩散控制过程的回火稳定性问题可以用Arrhenius方程较好地描述,其中系数A的取值很关键。计算结果表明012Al钢的回火稳定性低于含W元素的H21钢,而与普通热作模具钢H13接近。

Precipitation orientation effect of 2124 aluminum alloy in creep aging

The precipitation behaviors of 2124 aluminum alloy under the conditions of artificial aging （AA）, creep aging （CA） and creep aging with pre-deformation （PCA） were investigated by means of mechanical property and microstructure. The results show that the mechanical properties of CA treated sample decrease significantly compared with AA treated sample. The yield strength of the CA treated sample falls by 14%, the tensile strength falls by 6.2%, and the elongation falls by 21%. Nevertheless, the mechanical properties of PCA sample are improved obviously, close to the AA treated sample. Moreover, the generation and control mechanisms of the precipitation orientation effect in 2124 aluminum alloy were studied. It is deduced that the key mechanism lies in the effect of dislocation.

教育生态视角下研究生和谐师生关系构成及其影响因素——基于应用型高校的调查分析

研究生教育高质量发展离不开和谐融洽的师生关系,这种关系的建立是在师生交互的基础上多因素共同作用的结果。结合应用型高校的调查分析,基于教育生态视角,以师生交互行为为基础,建立和谐师生关系架构,并运用QCA组态分析法,从教师职业素养、学生综合素质、师生交互及外部环境等方面综合评价多重并发因素对研究生和谐师生关系的影响,提出高和谐师生关系的5种类型组态:学术基础型、制度约束型、教师主动科研型、学生主动复合型以及教师主动复合型,为应用型高校创造师生间良性互动氛围、建立健全外部制度保障、促进形成和谐师生关系提供参考。

Influence of spiral crystal selector on crystal orientation of single crystal superalloy

To increase efficiency and improve performance, reducing cost and emissions, advanced single crystal Ni-based superalloys are required in aerospace propulsion and power generating gas turbines. With the development of alloy, significant improvements in casting techniques have been achieved by introducing the directionally solidified （DS） casting process followed by single crystal （SX） technique. The deviation of preferred orientation of single crystal superalloys is one of the most important defects in casting. In directional solidification equipment with high temperature gradient, single crystal specimens of DZ417G alloy were prepared successfully by the modified Bridgeman method with spiral grain selector. The orientation was investigated by means of X-ray diffraction （XRD） and electron backscattered diffraction （EBSD）.The results show that the crystal selector with a smaller angle can effectively reduce the deviation of preferred orientation.