学术文献：研究前沿/研究热点

　　研究前沿为研究领域内最新文献；

　　研究热点为研究领域内高被引文献；

　　每期会选择一类文献进行推送，本期为“研究前沿”。

　　1.Heavymetal pollution risk of desulfurized steel slag as a soil amendment in cyclinguse of solid wastes

　　Abstracts：Theby-product of wet flue gas desulfurization, desulfurized steel slag (DS), hadchemical characteristics like natural gypsum that can be used to improvesaline-sodic soil. However, contamination risk of heavy metals for cyclingutilization of DS in agriculture was concerned mostly. Both pot and fieldexperiments were conducted for evaluating the potential pollution risk of DS asthe amendment of saline-sodic soil. Results showed that application of DSdecreased the contents of Cd, Cu, Zn, and Pb, while significantly increasingchromium (Cr) content in DS-amended soils. The field experiment demonstratedthat the migration of heavy metals (Cd, Zn, Cu, and Pb) in the soil profile wasnegligible. The application of DS at the dosage of 22.5-225 tons/hasignificantly increased the Cr content in alfalfa (Medicago sativa L.) butlower than the national standard for feed in China (GB 13078-2017). DS alteredthe chemical fraction of heavy metals (Zn, Cu, and Pb), transferredexchangeable, reducible into oxidizable and residual forms in DS-amended soil.Application of DS combined with fulvic acid (FA) could effectively reduce themovement of heavy metals in soil and the accumulation of Cr in alfalfa. Basedon our results, DS was a safe and feasible material for agricultural use andpresented relatively little pollution risk of heavy metals. However, theresults also showed that DS to a certain extent had a potential environmentalrisk of Cr if larger dosages of DS were used.

　　2.Efficient adsorption and reduction of Cr(VI) by a novel polyaniline modifiedmagnetic iron-based waterworks sludge from aqueous solution

　　Abstracts：As amajor solid waste from the waterworks, the iron-based waterworks sludge (IBWS)was currently disposed of in landfills or discharged into water body, causingland consumption and environment contamination. This work investigated a novelreclamation of IBWS to create a composite for aqueous Cr(VI) adsorption andreduction. IBWS was magnetized by calcination and further modified withpolyaniline (PANI) to get PANI@MIBWS for enhanced adsorbent separation andCr(VI) removal. After being characterized using advanced techniques, thecomposite was employed in aqueous Cr(VI) removal studies. PANI@MIBWS removedCr(VI) in a pH-dependent manner, with the highest Cr(VI) removal at pH 2. Thespontaneous and endothermic Cr(VI) elimination process by the composite wasbest explained by pseudo-second-order and Langmuir models. In the sequence ofCl-< SO42-of IBWS, but also useful information for Cr(VI)-bearing wastewatertreatment.

　　3.Fabrication of anovel composite gel bead to reclaim methyl orange from a binary dye mixture: Anactive role of adsolubilization phenomenon

　　Abstracts：Thepresent work demonstrates a novel protocol in accordance with the reduce,reuse, and recycle principle of waste management rules for dye wastewatertreatment as well as selective extraction of desired dye. Here two model dyesviz., methyl orange (MO) (an anionic dye) and methylene blue (MB) (a cationicdye) have been considered as the components of dye wastewater, andalginate-xanthan (Alg-Xan) biopolymer composite hydrogel beads modified with acationic surfactant such as cetylpyridinium chloride (CPC), as the sorbentma-terial. CPC bilayers on Alg-Xan composite surface showed excellent MO uptakeperformance (>85-90%) via adsolubilization when the MO is present alone orin a binary mixture with MB. On the other hand, MB got partially transferred(-30-50%) to the solid surface through diffusion phenomenon both in thepresence (-50%) and absence (-30%) of MO. After the accumulation of the dyemolecules, MO can be easily reclaimed (>90%) using 1-butanol as theextracting solvent; however, no detachment of MB from the solid surface takesplace. The stability and suitability of the hydrogel beads were investigatedunder different operating conditions. Further-more, Alg-Xan-CPC composite beadshave been characterized using FTIR, SEM analysis, and particle sizedis-tribution. The newly developed Alg-Xan-CPC composite beads show goodreusability up to four cycles and they perform well in real wastewater (-95%recovery of MO). The novelty of the current research includes the synthesis ofa CPC micelle anchored biopolymer adsorbent, which is capable of attractingboth the cationic and anionic dyes from water bodies, followed by extractivereclamation of the anionic dye only. The application of biopolymers forwastewater treatment and resource recovery from the waste stream is undoubtedlya sustainable environmental remediation option. Hence, this research work isexpected to present a novel application of biopolymers for dye wastewatermitigation as well as reclamation of desired useful dye.

　　1.A review ofelectrical and thermal conductivities of epoxy resin systems reinforced withcarbonnanotubesand graphene-based nanoparticles

　　Abstracts：Epoxy(EP) resins exhibit desirable mechanical and thermal properties, low shrinkageduring cuing, and high chemical resistance. Therefore, they are useful forvarious applications, such as coatings, adhesives, paints, etc. On the otherhand, carbon nanotubes (CNT), graphene (Gr), and theirderivatives have become reinforcements of choice for EP-based nanocompositesbecause of their extraordinary mechanical, thermal, and electrical properties.Herein, we provide an overview of the last decade???s advances in research onimproving the thermal and electrical conductivities of EP resin systemsmodified with CNT, Gr, their derivatives, and hybrids. We further report on thesurface modification of these reinforcements as a means to improve thenanofiller dispersion in the EP resins, thereby enhancing the thermal andelectrical conductivities of the resulting nanocomposites.

　　2.2Dmaterials and heterostructures for photocatalytic water-splitting: atheoretical perspective

　　Abstracts：Photocatalyticwater-splitting for hydrogen generation by sunlight provides a new route toaddress energy and environmental problems. In recent years, tremendous effortshave been devoted to designing highly efficient water-splitting photocatalysts(PCs). Adequate light absorption, effective photogenerated carrier separation,and sufficiently large overpotentials for water redox are crucial in achievinghigh solar-to-hydrogen (STH) efficiency. These parameters thus stronglyinfluence the design of novel photocatalytic materials. Two-dimensional (2D)PCs have flourished because of their large specific surface area ratio, shortcarrier migration distance compared to bulk PCs, enormous design flexibility viavan der Waals heterostructure (HS) engineering and many other uniquecapabilities that meet the criteria for high-efficiency STH conversion. In thisreview, we summarize the recent developments of 2D materials and HSs forwater-splitting applications from a theoretical perspective. Specifically, wefirst discuss a number of 2D materials and HSs employed for water-splitting. Wereview various strategies of material design to modulate and enhance thephotocatalytic performance via improving light harvesting and carrierseparation, such as the introduction of defects and dopants, and theapplication of strain, external electric field, rotation angles andferroelectric switching. We then discuss the methods to evaluate hydrogenevolution reaction, oxygen evolution reaction and STH efficiency. Finally, theopportunities and challenges of designing 2D materials and HSs forwater-splitting are presented.

　　3.Greensynthesis of DyBa2Fe3O7.988/DyFeO3 nanocomposites using almond extract withdual eco-friendly applications: Photocatalytic and antibacterial activities

　　Abstracts：For thefirst time, photocatalytical and antibacterial activities ofDyBa2Fe3O7.988/DyFeO3 (Dy-Ba-Fe-O) nanocomposites as eco-friendly applicationsof this compound was studied in the same time. Since the applications of thiscompound are eco-friendly, ultrasound technique was chosen as the synthesismethod. Achieving the pure product with good crystallinity with the lowestenergy consumption can be considered as one of the advantages of this work.Using the almond core extract as a natural reagent was another reason forconsideration this method as a green process. Band gap of this nanocompositewas estimated about 2.6 eV that showed this product can be used as avisible-active photo catalyst. Rhodamin-B dye as an organic pollutant modelusing the as-prepared nano composite was degraded about 72% that was aconsiderable result under visible irradiation. Elimination of microorganismswas studied by disc diffusion to recognize the sensitivity of bacterial(Staphylococcus aureus, Bacillus subtilis, E. coli, K. pneumonia and P.aeruginosa) strains the manufactured. The results confirmed thatDyBa2Fe3O7.988/DyFeO3 (DBFeO) nanocomposites can be used as an antibacterialagent because of the manifested strong antibacterial ability upon Gram-negativepathogens such as K. pneumonia and E. coli. The properties of this product werecharacterized by different analyses including SEM, XRD, EDS, FT-IR, DRS andTEM. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. Allrights reserved.

　　4.PolycrystallineSnSe with a thermoelectric figure of merit greater than the single crystal

　　Abstracts：Thermoelectricmaterials generate electric energy from waste heat, with conversion efficiencygoverned by the dimensionless figure of merit, ZT. Single-crystal tin selenide(SnSe) was discovered to exhibit a high ZT of roughly 2.2-2.6 at 913 K, butmore practical and deployable polycrystal versions of the same compound sufferfrom much poorer overall ZT, thereby thwarting prospects for cost-effectivelead-free thermoelectrics. The poor polycrystal bulk performance is attributedto traces of tin oxides covering the surface of SnSe powders, which increasesthermal conductivity, reduces electrical conductivity and thereby reduces ZT.Here, we report that hole-doped SnSe polycrystalline samples with reagentscarefully purified and tin oxides removed exhibit an ZT of roughly 3.1 at 783K. Its lattice thermal conductivity is ultralow at roughly 0.07 W m(-1) K-1 at783 K, lower than the single crystals. The path to ultrahigh thermoelectricperformance in polycrystalline samples is the proper removal of the deleteriousthermally conductive oxides from the surface of SnSe grains. These resultscould open an era of high-performance practical thermoelectrics from thishigh-performance material.

　　SnSehas a very high thermoelectric figure of merit ZT, but uncommonlypolycrystalline samples have higher lattice thermal conductivity than singlecrystals. Here, by controlling Sn reagent purity and removing SnOx impurities,a lower thermal conductivity is achieved, enabling ZT of 3.1 at 783 K.

　　1.Asurvey on vision guided robotic systems with intelligentcontrol strategies for autonomous tasks

　　Abstracts：TheVision Guided Robotic systems (VGR) is an essential aspect of modernintelligent robotics. The VGR is rapidly transforming manufacturing processesby enabling robots to be highly adaptable and intelligent reducing the cost andcomplexity. For any sensor-based intelligent robots, vision-based planning isconsidered as one of the most prominent steps followed by controlled actionsusing visual feedback. To develop robust vision-based autonomous systems inrobotic applications, path-planning and localization can be implemented alongwith Visual Servoing (VS) for robust feedback control. In the availableliterature, most of the reviews are focused on a particular module ofautonomous systems like path planning, motion planning strategies, or VisualServoing techniques. In this paper overall review of different modules invision-guided robotic systems is presented. So, this review providesresearchers with broader in-depth knowledge about different modules that existin the vision-guided autonomous system. The review also includes differentvision sensors that are commonly used in industries covering theircharacteristics and applications. In this work, overall, 227 research papers inpath planning and vision-based control algorithms are reviewed with recentintelligent techniques based on optimization and learning-based approaches. Thegraphical analysis illustrating the advancements of research in the field ofvision-based robotics using Artificial Intelligence (AI) is also discussed.Lastly, this paper concludes by discussing some of the research gaps,challenges, and future directions existing in vision-based planning andcontrol.

　　2.Ahierarchical intelligent control strategy for greenhouse gasreduction in wastewater treatment process of paper mill

　　Abstracts：Due tothe huge amounts of wastewater discharge and the high pollution loads inpapermaking industry, many greenhouse gases (GHG) are emitted in thepapermaking wastewater treatment process. The wastewater dis-solved oxygen (DO)control has been considered as the most cost-effective control solution for GHGreduction in wastewater treatment plants (WWTP). However, the competitionbetween contaminant removal efficiency and GHG reduction hinders the drasticreduction of GHG emissions from WWTP. In this study, based on the estab-lishedintegrated GHG emission model, explicitly considering the total GHG reductiontargets on the premise of effluent compliance, an intelligent control schemehas been developed for an activated sludge process in a paper mill. RegardingDO as the controlled variable, the proposed hierarchical optimalproportional-integral (HOPI) control scheme was established consisting of threelayers: 1) Layer 1 for the effluent quality estimation, 2) Layer 2 for theoptimal DO set point determined by genetic algorithm with the influentvariations to obey discharging norms and reduce GHG emissions, 3) Layer 3 forthe DO tracking proportional integral (PI) control with the controllerparameters adjusted by the back propagation neural network to track thedynamically optimized DO set points. The simulation results showed that,compared with the open-loop (OL) operation (averaged aeration, 10/h), theproposed HOPI control (averaged aeration, 7.9/h) reduced the GHG emissions by12.54% under the premise of discharging norms, which was mainly attributed tothe reduction of the aeration electricity con-sumption. In contrast, the PIcontrol (averaged aeration, 12.9/h) increased the GHG emissions by 7.48%compared with the OL operation. Thus, the proposed HOPI control strategy hasdemonstrated potential for the application of GHG reduction in industrial WWTPs.

　　3.Intelligentcontrol of nanoparticle synthesis on microfluidic chips with machine learning

　　Abstracts：Nanoparticlesplay irreplaceable roles in optoelectronic sensing, medical therapy, materialscience, and chemistry due to their unique properties. There are many syntheticpathways used for the preparation of nanoparticles, and different syntheticpathways can produce nanoparticles with different properties. Therefore, it iscrucial to control the properties of nanoparticles precisely to impart thedesired functions. In general, the properties of nanoparticles are influencedby their sizes and morphologies. Current technology for the preparation ofnanoparticles on microfluidic chips requires repeated experimental debuggingand significant resources to synthesize nanoparticles with precisely thedesired properties. Machine learning-assisted synthesis of nanoparticles is asensible choice for addressing this challenge. In this paper, we review manyrecent studies on syntheses of nanoparticles assisted by machine learning.Moreover, we describe the working steps of machine learning, the main algorithms,and the main ways to obtain datasets. Finally, we discuss the current problemsof this research and provide an outlook.

　　1.State-of-the-artapplications of machine learning in the life cycle of solid wastemanagement

　　Abstracts：Due tothe superiority of machine learning (ML) data processing, it is widely used inresearch of solid waste (SW). This study analyzed the research anddevelopmental progress of the applications of ML in the life cycle of SW.Statistical analyses were undertaken on the literature published between 1985and 2021 in the Science Citation Index Expanded and Social Sciences CitationIndex to provide an overview of the progress. Based on the articles considered,a rapid upward trend from 1985 to 2021 was found and international cooperativeswere found to have strengthened. The three topics of ML, namely, SW categories,ML algorithms, and specific applications, as applied to the life cycle of SWwere discussed. ML has been applied during the entire SW process, therebyaffecting its life cycle. ML was used to predict the generation andcharacteristics of SW, optimize its collection and transportation, and modelthe processing of its energy utilization. Finally, the current challenges ofapplying ML to SW and future perspectives were discussed. The goal is toachieve high economic and environmental benefits and carbon reduction duringthe life cycle of SW. ML plays an important role in the modernization andintellectualization of SW management. It is hoped that this work would behelpful to provide a constructive overview towards the state-of-the-artdevelopment of SW disposal.

　　2.Asurvey on machine learning for recurring concept drifting datastreams

　　Abstracts：Theproblem of concept drift has gained a lot of attention in recent years. Thisaspect is key in many domains exhibiting non-stationary as well as cyclicpatterns and structural breaks affecting their generative processes. In thissurvey, we review the relevant literature to deal with regime changes in thebehaviour of continuous data streams. The study starts with a generalintroduction to the field of data stream learning, describing recent works onpassive or active mechanisms to adapt or detect concept drifts, frequentchallenges in this area, and related performance metrics. Then, differentsupervised and non-supervised approaches such as online ensembles,meta-learning and model-based clustering that can be used to deal withseasonalities in a data stream are covered. The aim is to point out newresearch trends and give future research directions on the usage of machinelearning techniques for data streams which can help in the event of shifts andrecurrences in continuous learning scenarios in near real-time.

　　3.Identificationand classification of coronavirus genomic signals based on linear predictivecoding and machine learning methods

　　Abstracts：Coronadisease has become one of the problems and challenges of humankind over thepast two years. One of the problems that existed from the first days of thisepidemic was clinical symptoms similar to other infectious vi-ruses such ascolds and influenza. Therefore, diagnosis of this disease and its coping andtreatment approaches is also been difficult. In this study, Attempts has beenmade to investigate the origin of this disease and the genetic structure of thevirus leading to it. For this purpose, signal processing and linear predictivecoding approaches were used which are widely used in data compression. Apattern recognition model was presented for the detection and separation ofcovid samples from the influenza virus case studies. This model, which wasbased on support vector machine classifier, was tested successfully on severaldatasets collected from different countries. The obtained results performed onall datasets by more than 98% accuracy. The proposed model, in addition to itsgood performance accuracy, can be a step forward in quantifying and digitizingmedical big data information.

　　Keywords：Linearpredictive codingCoronaDNA SequenceSupportvector machineSignalprocessingMachinelearning

　　1.Theimpact of internet penetration on venture capital investments: Evidence from aquasi-natu

　　Abstracts：Thisstudy investigates the relationship between interne ral experimentt penetrationand venture capital (VC) investment in China. Exploiting staggered inclusion indemonstration cities under the Broadband China strategy as a positive shock tointernet penetration, our difference-in-differences analysis shows that thispolicy shock results in an increase in VC investments in demonstration citiesrelative to others. Moreover, the increase in VC investments is concentrated inearly stage financing and young start-ups. In terms of VC fundsources, we find a stronger effect on foreign and independent VCs. Ourmechanism analysis suggests that the effect of the broadband rollout is mainlydriven by cities with higher ex-ante costs of information acquisition and thatsuch costs are reduced by the improvement of internet-based networkinfrastructure. Finally, we provide additional evidence on the benefits toestablished companies by showing that broadband rollout improves the informationenvironment of listed firms. Our study sheds new light on the economicconsequences of infrastructure development that reduces information acquisitioncosts in China.

　　2.TheBurden of Cold Agglutinin Disease on Patients' Daily Life: Web-BasedCross-sectional Survey of 50 American Patients

　　Abstracts：Background:Cold agglutinin disease (CAD) is a rare disorder, affecting 15% of patientswith autoimmune hemolytic anemia. Few studies have assessed CAD symptoms andtheir impact on daily life, but these studies did not address the patients'perspectives.

　　Objective:The aims of this study were to increase the knowledge about CAD through apatient-centric survey and to gain a better understanding of the burden of thisdisease. Methods: We conducted an internet-based survey in September2020 among American patients registered on the CAD Unraveled website andmembers of the Cold Agglutinin Disease Foundation.

　　Results:A total of 50 respondents were included in this study. Totally, 90% (45/50) ofthe patients reported having experienced fatigue. Fatigue was mainly reportedon a daily basis, and approximately one-third of these patients (13/45, 29%)said that their fatigue was constant throughout the day. It has also been shownthat CAD has a great impact on patients' physical well-being, emotionalwell-being, social life, and household finances. The disease varies over time,with or without symptoms. A total of 88% (44/50) of the patients reported previousepisodes of the increased intensity or sensitivity of their CAD symptoms, witha mean of 4.5 (SD 5.4) episodes reported during the past year. More than halfof the patients (27/50, 54%) considered their disease to be moderate or severe,and 42% (21/50) of the study group reported that their symptoms had worsenedsince the time of diagnosis.

　　Conclusions:Our study has provided new data on CAD symptoms, particularly data on theimportance and type of fatigue and the fluctuation of CAD symptoms.

　　3.Paralyzed by shock: the portfolio formation behavior of peer-to-businesslending investors

　　Abstracts：Weexamine investor behavior on a leading peer-to-business lending platform andidentify an investment mistake that we refer to as default shock bias. First,we find that investors stop investing in new loans and cease diversifying theirportfolio after experiencing a loan default. The default shock significantlyworsens the risk-return profile of investors' loan portfolios. The defaultsinvestors experience are often not beyond what would have been expected fromthe information that was provided by the platform ex ante. Second, investmentexperience on the platform is related to better investment decisions ingeneral, but it does not reduce the default shock bias. These findings haveimportant implications not only for the behavioral finance literature but alsomore generally for new forms of Internet-based finance.

　　1. 基于“少数派报告”的协同过滤模型

　　摘要：协同过滤是在线推荐系统最重要的组成模块之一，为实现面向用户的个性化广告投放功能提供了关键的技术支持。然而，在协同过滤系统的具体实现中，研究者却不加区分的对所有目标用户都使用相同的训练流程。较之“个性化的预测结果”的预期，上述“一般化的训练过程”使得结果模型相对于待预测的目标过于普适，缺乏必要的针对性。本文提出一个“以个性化的训练过程得到个性化的预测结果”的协同过滤预测模型（MORE）：对给定的目标用户，MORE将使用弹性网络模型（ElasticNet），从现有的用户全集中选出若干用户构成与之对应的“专家”集合，并基于目标用户与专家已有的评分，生成对目标用户的缺失评分的预测。本文报告了MORE在不同的协同过滤预测模型上的应用结果，在真实评分数据集上的实验结果表明，较之使用全量数据训练得到的预测模型，基于MORE的模型有更好的表现。 

　　2.  人员流动与城市间商品价格差异:来自高铁开通的证据

　　摘要：本文以中国高铁开通这一自然实验，采用2001-2016年172个地级市的微观商品价格数据，运用倍差法研究人员流动对城市间商品价格差异的影响。研究表明，高铁开通带来的人员流动，能通过促进要素市场一体化和地区间商务往来，显著降低城市间商品价格差异，由此促进地区间产品市场的一体化。通过更换多个代理变量、控制时间趋势、使用基于随机模拟方法的安慰剂检验和事件分析法等多种方法进行稳健性检验，并分别构建了基于最低成本原则和最短距离原则的最小生成树作为两个工具变量来处理内生性问题后，研究结论依然成立。进一步研究表明，高铁开通能推动区域内、区域间以及不同行政级别城市间的经济一体化；高铁站的合理选址与高铁线路的合理设计对充分发挥高铁开通的作用有重要影响。

　　3.  建设有中国特色的比较教育学：动因、逻辑与路径转向

　　摘要：建设有中国特色的比较教育学是中国比较教育工作者现在及未来所要承载的重要任务和使命。比较教育学科自身的文化属性、现代化社会的发展需求、中国特色社会主义理论的提出与发展以及中国比较教育学者危机心理的产生，共同构成了中国特色比较教育学科建设的动因。要进一步推动中国特色比较教育学科建设，一方面要在学科生成逻辑上理清其内在的哲学逻辑、文化逻辑、实践逻辑以及价值逻辑，另一方面则要在纵向时间序列上明晰中国特色比较教育学科建设的路径转向，以便更好地推动中国比较教育学的高质量发展。 

　　4.  高校VR英语课堂构建——评《基于虚拟现实的计算机辅助语言教学研究》

　　摘要：当今科技领域最火的概念,无疑就是“元宇宙”,其概念最早出自1992年的美国科幻小说《雪崩》,2018年著名导演斯皮尔伯格的《头号玩家》生动展示了元宇宙的一种可能形态。元宇宙是一个“去中心化”的,具有超强沉浸感的大型虚拟世界,是一种操作系统级别的存在。所有接入元宇宙的应用程序都必须遵循一套相同的底层协议,在元宇宙中所有数据都是真实的,包括个人的经济、身份和影响力等。元宇宙包括了目前已知的所有高端科技和概念,如Al、VR、AR、MR、区块链、NFT和5G等,VR+教育、VR+社交、VR+购物、VR+旅游和VR+运动等都是元宇宙的一部分。元宇宙与现实世界实时交互,在元宇宙中所发生的一切都是真实的。VR+教育是元宇宙的重要组成部分,将虚拟现实技术应用于外语教学领域也引发了广大教育工作者的关注,深入研究“VR+外语教育”已成为科技和时代发展的必然。马冲宇著作的《基于虚拟现实的计算机辅助语言教学研究》一书有助于高校外语教师研究如何利用虚拟现实技术来构建VR英语课堂。

　　1.对外话语体系视域下汉硕留学生高质量培养探究

　　摘要：本研究采用“对外话语体系”理论作为分析的切入点,分别从话语主体、话语内容、话语方式三个层面对汉硕留学生的培养问题进行分析,以期展现培养中所面临的问题及应对策略,从一个更全面的角度揭示汉硕留学生人才培养的实施情况。具体而言,在话语主体层面,学校容易忽略留学生在文化选择上的诸多不同,走进同质化的培养误区;在话语内容层面,教材选择存在着国内外生源重重交叉,内容有传统化倾向,缺少现当代中国文化的融入,时代性、针对性、灵活性等明显不足;在话语方式层面,教学话语单一化、互动性不足,缺少分析留学生学情,出现了“课堂焦虑”问题。为此提出如下对策:（1）明确对外话语主体的重点,立足于留学生的文化背景,进行细致的话语主体分类,突出培养重点的群体效应;（2）增强教材话语内容的丰富性,体现多元的国别化特色,以美好生活为引领,寻找中外语言文化的共通点;（3）增添教学话语风格的多样性,融合不同的话语形态和叙述视角,以对话交流增强教学话语的互动性;（4）通过教师话语人才专业能力的整体提升来促进教学质量的有效落实。

　　2.国际中文新、熟手教师课堂指令语类型对比研究

　　摘要：选取5名新手和5名熟手国际中文教师，运用课堂观察、访谈和录音对两者课堂指令语类型进行对比研究。两者的共性是倾向于使用简洁、直接的形式，回避语义复杂、可能造成学生误解的形式。差异性是新手频繁使用单一类型的指令语，指令语气过于强硬，礼貌程度较低。熟手则能够利用丰富多变的指令语为学生提供与其中文水平相匹配的语言输入。造成两者课堂指令语差异的主要因素包括教学经验、实践性知识、自信心、对教师权威的认知、对课堂角色的定位等。新手应加强对学生学习情绪和体验的关注；利用撰写教学日志等方法反思自身指令语的使用情况；发挥非言语交际手段的辅助作用；在教师共同体中学习熟手使用指令语的经验，以促进课堂教学效率的提升。

　　3.现代汉语工具动量词的指称功能考察：认知语法视角

　　摘要：语法学界一般认为，现代汉语工具动量词的作用是作为动量标记或分类标记。本文在大规模真实语料中观察后提出，工具动量词一个重要的语义功能是通过概念转喻的机制实现动作事件的指称，其作用与动作动词的名物化形式相当。专用动量词也可以指称动作，但使用频率和概念自主程度都很低。工具动量词的事件指称功能在以往研究中一直没有受到重视，但它是汉语区别于英语等印欧语的一个重要个性。

08外语与文化传播学院

　　Abstracts：Presentstudy reveals the flow of a classical non-Newtonian fluid based on theWilliamson model through a vertical flat plate. The free convective flow isgenerated because of the effect of buoyancy relating to the temperature. Inaddition to that, the influence of thermal radiation and heat source/sink inconjunction with the dissipative heat enhances the efficiency of transportphenomenon within the bounding surface. Well-proposed similarity transformationis used to transform the governing equation into ordinary.However, due to the dissipation, the nonlinear coupled problems are complex.For the solution, a semi-analytical approach suchas differential transformation method (DTM) in association with thePade approximant method is used instead of traditional numerical technique.Pade-approximant is useful to get a non-iterative solution without imposing themissing boundary conditions. It is a simple and effective way to determine thesolutions of complex nonlinear problems with assumed boundary conditions atinfinity. The physical significance of all the contributing parametersdistinguished the flow properties are achieved and accessible graphically.Moreover, the validation of the present methodology with the traditionalnumerical technique is obtained, showing an excellent correlation in particularcases.

　　Abstracts：Weconsider the Cauchy problem for a first-order evolution equation withmemory in a finite-dimensional Hilbert space when the integral term is relatedto the time derivative of the solution. The main problems of the approximatesolution of such nonlocal problems are due to the necessity to work with theapproximate solution for all previous time moments. We propose a transformationof the first-order in-tegrodifferential equation to a system of localevolutionary equations. We use the approach known in the theory of Volterraintegral equations with an approximation of the difference kernel by the sum ofexponents. We formulate a local problem for a weakly coupled system ofequations with additional ordinary differential equations. We havegiven estimates of the stability of the solution by initial data and theright-hand side for the solution of the corresponding Cauchy problem. Theprimary attention is paid to constructing and investigating the stability oftwo-level difference schemes, which are convenient for computationalimplementation. The numerical solution of a two-dimensional model problem forthe evolution equation of the first order, when the Laplace operatorconditions the dependence on spatial variables, is presented. (c) 2022 ElsevierB.V. All rights reserved.

　　Abstracts：In this study, a variable step size formulation ofmulti-step general Runge-Kutta- Nystrom (MSGN) methods to directly integrategeneral second-order initial value prob-lems (IVPs) is considered. This formulais carried out using an embedded explicit pair where: the higher-order formulais an accurate and the lower-order formula uses to estimate the local error.Numerical results show that the new methods perform much better in terms offunctions evaluations, implementation cost and execution time compared to otherexisting high quality embedded Runge-Kutta (ERK) methods in the literature.(c)2022 Elsevier B.V. All rights reserved.