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EXPLORING TEACHING INTONATION TO TERTIARY EFL-MAJOR STUDENTS

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Chinese Journal of Applied Linguistics 2003年第3期26卷 38-44,127页

作者：张军甘肃教育学院(新加坡)南洋理工大学

In view of current advocacy of the Communicative Language Teaching (CLT) and the eclectic approach among teachers in both tertiary and middle levels, this paper discusses possibilities of teaching intonation to EFL-major students at teachers' colleges/universities. It starts by reviewing recent writings about whether or not pronunciation/intonation should be taught in second/foreign language programmes. It then reviews research into the teaching of the pronunciation of English as a second/foreign language to clear the background for a proposal to teach intonation in tertiary institutions where teacher-education is the major concern. Working within Kingdon's theoretical framework, it first explores the theoretical issues involved in teaching intonation; it then suggests practical hands-on ideas for classroom implementation.

关键词：英语专业学生师范院校语调教学英语语调教学探索可行性中小学英语教师回顾教学主张交际教学

Phytochemical and Pharmacological Properties of Radix Codonopsis:A Review

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Phytochemical and Pharmacological Properties of Radix Codono...

海峡两岸暨CSNR全国第十届中药及天然药物资源学术研讨会

作者： Sufang Gao,Huizhen Wang,Cuiyun Zeng,Jia Hou,Yanhong zhang (gansu College of Traditional Chinese Medicine,Lanzhou,730000)

Radix Codonopsis(RC) was a well-known Chinese traditional herbal *** could improve the blood glucose level,immune,digestive,hematopoietic and coagulation function,and stimulate the *** clinical practice,RC was usually used to cure poor appetite,dyspepsia,fatigue,psychoneurosis,inflammatory diseases etc. Recently,many studies focused on its antitumor,antioxidant,anti-aging,anti-ulter,and antibacterial *** the utilization of resource,more new medicine species of the same generic plants should be developed and *** paper was a review of the phytochemical and pharmacological properties of ***,the application prospect of RC was also *** reviewing these achievements,it could be seen that RC has very bright future.

关键词： Chinese material medica Radix Codonopsis(RC) phytochemistry pharmacology

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盘梗霉属一新种——甜菜盘梗霉

真菌学报 1985年第3期 141-143页

作者：白宏彩程秀英孟有儒甘肃农业大学张掖农校甘肃武威甘肃张掖

本文报道了寄生于藜科(Chenopodiaceae)甜菜(Beta vulgaris L.)上的盘梗霉属一新种——甜菜盘梗霉(Bremia betae ***.)。对此新种作了汉文和拉丁文描述。

关键词：甜菜盘梗霉甜菜

干法重介质流化床压力多尺度分析与流化质量表征

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煤炭科学技术 2023年第4期51卷 215-223页

作者：张赣苏董良周恩会周晨阳段晨龙赵跃民中国矿业大学煤炭加工与高效洁净利用教育部重点实验室江苏徐州221116 中国矿业大学化工学院江苏徐州221116

选煤是煤炭清洁加工利用的源头技术,干法选煤是干旱缺水地区与易泥化煤炭高效分选提质的重要途径。干法重介质流化床通过上升气流驱动加重质颗粒流化形成一定密度的气固流态化床层,实现对煤炭按密度分选,床层密度均匀稳定性即床层流化... 详细信息

选煤是煤炭清洁加工利用的源头技术,干法选煤是干旱缺水地区与易泥化煤炭高效分选提质的重要途径。干法重介质流化床通过上升气流驱动加重质颗粒流化形成一定密度的气固流态化床层,实现对煤炭按密度分选,床层密度均匀稳定性即床层流化质量是决定分选精度的关键。受到气流、气泡、运动内构件、入料等多因素扰动,床层流化行为复杂多变,压力信号呈现出非均匀性、非线性、多尺度特征。基于干法重介质流化床压力信号的轴向差异传递与横向等效扩散特性,着重研究了床层轴向压差波动特征,提出流化质量定量表征方法。结果表明:基于时域分析可知,Geldart A类加重质颗粒床层总压降概率密度分布接近于正态分布;当床层散式膨胀时,由于颗粒间接触力的分布不均,概率密度呈现右偏且尖峰的偏离正态分布。通过频域分析发现,在床层膨胀区间的中末期,气泡主频主导了流化床的整个轴向区间;完全流化后的流化床,气泡主频仅控制着床层中部区域,床层浓度信号主频沿床层轴向分布变化明显。结合时域和频域信号分析结果,提出以轴向床层浓度主频为子区间波动标准差权重值的流化质量表征模型,可以综合评估干法重介质流化床的密度分布均匀性和稳定性,为干法重介质流化床分选密度稳态调控与精准分选提供有力支撑。

关键词：干法选煤干法重介质流化床压力信号分析流化质量表征

Protective benefit of folded linear HDPE board sand fences along the Golmud-Korla Railway,China:Field observation and wind tunnel study

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Journal of Mountain Science 2024年第7期21卷 2206-2219页

作者： zhang Kai TIAN Jianjin WANG Zhenghui zhang Hailong zhang Xingxin College of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730000China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Civil Engineering Chongqing UniversityChongqing 400045China

The Milan Gobi area of the Golmud-Korla Railway in northwest China is located in the lower dispersal area of the mountain pass and has strong winds with evident double wind direction *** study introduced a novel sand fence deployment technique,termed‘folded linear deployment',designed to position the sand fence orthogonally to the two predominant wind directions for optimal *** study used wind tunnel and field tests to evaluate the wind and sand flow characteristics,as well as the windproof and sandresistant performance of folded linear HDPE(Highdensity polyethylene)board sand *** results suggest that the airflow around the fence creates clear zoning *** deceleration area on the BSF(backwind side of the sand fence)is much larger than that on the DSF(downwind side of the sand fence).Thus,sand particles are primarily deposited on the *** different wind speeds,the airflow at 2 and 5 h on the DSF is not *** WSP(wind speed profile)presents a logarithmic *** airflow is disturbed at 1-20 h on the BSF,and the WSP gradually deviates from the logarithmic ***,as the airflow moves away from the fence,the WSP gradually approaches a logarithmic ***,the WPE(windproof efficiency)and SRE(sand-resistant efficiency)of the sand fence exceed 80%.In addition,the results of wind tunnel tests are compared with those of field *** overall dispersion is good,and the best dispersion is found at z/H=2.00,indicating good agreement between the two test *** study provides a scientific basis for the design of sand hazard control measures,similar to the railway project in the Gobi Gale area.

关键词： Folded linear HDPE board sand fence Double wind direction Gobi area Protection benefit

High-efficiently doping nitrogen in kapok fiber-derived hard carbon used as anode materials for boosting rate performance of sodium-ion batteries

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Journal of Energy Chemistry 2024年第9期96卷 472-482页

作者： Tianyun zhang Tian zhang Fujuan Wang Fen Ran School of Mechanical and Electronical Engineering Lanzhou University of TechnologyLanzhou 730050GansuChina State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals School of Materials Science and EngineeringLanzhou University of TechnologyLanzhou 730500GansuChina

The engineering of plant-based precursor for nitrogen doping has become one of the most promising strategies to enhance rate capability of hard carbon materials for sodium-ion batteries;however,the poor rate performance is mainly caused by lack of pyridine nitrogen,which often tends to escape because of high temperature in preparation process of hard *** this paper,a high-rate kapok fiber-derived hard carbon is fabricated by cross-linking carboxyl group in 2,6-pyridinedicarboxylic acid with the exposed hydroxyl group on alkalized kapok with assistance of zinc ***,a high nitrogen doping content of 4.24%is achieved,most of which are pyridine nitrogen;this is crucial for improving the defect sites and electronic conductivity of hard *** optimized carbon with feature of high nitrogen content,abundant functional groups,degree of disorder,and large layer spacing exhibits high capacity of 401.7 mAh g^(−1)at a current density of 0.05 A g^(−1),and more importantly,good rate performance,for example,even at the current density of 2 A g^(−1),a specific capacity of 159.5 mAh g^(−1)can be *** findings make plant-based hard carbon a promising candidate for commercial application of sodium-ion batteries,achieving high-rate performance with the enhanced pre-cross-linking interaction between plant precursors and dopants to optimize aromatization process by auxiliary pyrolysis.

关键词： Kapok fiber Hard carbon Electrode materials Rate performance Sodium-ion batteries

Near-surface wind field characteristics of the desert-oasis transition zone in Dunhuang,China

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Journal of Arid Land 2024年第5期16卷 654-667页

作者： PAN Jiapeng zhang Kecun AN Zhishan zhang Yu Key Laboratory of Desert and Desertification&Dunhuang Gobi and Desert Ecology and Environment Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

The desert-oasis transition zone(DOTZ)serves as a buffer area between the desert and *** its wind field characteristics is of great significance for the prevention and control of aeolian disasters in the *** this study,we used meteorological data during 2013–2019 from the portable meteorological stations at five sites(site A on the edge of the oasis,sites B,C,and D in the DOTZ,and site O in the desert)in Dunhuang,China to analyze the near-surface wind field characteristics and their causes,as well as to reveal the key role of the DOTZ in oasis *** results showed that the mean wind speed,frequency of sand-driving wind,and directional variability of wind decreased from west to east within the DOTZ,and wind speed was significantly affected by air *** terrain influenced the prevailing winds in the region,mainly from northeast and *** some areas adjacent to the oasis were controlled by southeasterly *** indicated that the near-surface wind field characteristics of the DOTZ were caused by the combined effects of local terrain and surface hydrothermal *** site D,the annual drift potential(DP)was 24.95 vector units(VU),indicating a low wind energy environment,and the resultant drift direction(RDD)showed obvious seasonal ***,the DOTZ played an important buffering role between the desert and *** with the desert,the mean wind speed in the oasis decreased by 64.98%,and the prevailing wind direction was more *** results of this study will be useful in interpreting the aeolian activity of the DOTZ in Dunhuang.

关键词： desert-oasis transition zone near-surface wind field hydrothermal difference sand-driving wind aeolian environment Dunhuang

Numerical simulation on sand sedimentation and erosion characteristics around HDPE sheet sand barrier under different wind angles

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Journal of Mountain Science 2024年第2期21卷 538-554页

作者： zhang Kai zhang Peili zhang Hailong TIAN Jianjin WANG Zhenghui XIAO Jianhua College of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730000China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

For the safety of railroad operations,sand barriers are utilized to mitigate wind-sand disaster *** disasters,characterized by multi-directional wind patterns,result in diverse angles among the *** this study,using numerical simulations,we examined the behavior of High Density Polyethylene(HDPE)sheet sand barriers under different wind angles,focusing on flow field distribution,windproof efficiency,and sedimentation erosion *** study discovered that at a steady wind speed,airflow velocity varies as the angle between the airflow and the HDPE barrier ***,a 90°angle results in the widest low-speed airflow area on the barrier’s downwind *** the airflow is not perpendicular to the barrier,it prompts a lateral airflow movement which decreases as the angle *** windproof efficiency correlates directly with this angle but inversely with the wind’s ***,with a wind angle of 90°,wind speed drops by 81%.The minimum wind speed is found at 5.1H(the sand barrier height)on the barrier’s downwind *** the angle grows,the barrier’s windproof efficiency improves,extending its protective *** is most prominent on the barrier’s downwind side,as the wind angle shifts from 30°to 90°,the sand sedimentation area on the barrier’s downwind side enlarges by *** the angle grows,sedimentation intensifies,eventually overtakes the forward erosion and enlarges the sedimentation area.

关键词： Multi-wind direction HDPE sheet sand barrier Numerical simulation Windproof efficiency Sedimentation erosion

Adaptive spatial-temporal graph attention network for traffic speed prediction

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High Technology Letters 2024年第3期30卷 221-230页

作者： zhang Xijun zhang Baoqi zhang Hong NIE Shengyuan zhang Xianli School of Computer and Communication Lanzhou University of TechnologyLanzhou 730050P.R.China

Considering the nonlinear structure and spatial-temporal correlation of traffic network,and the influence of potential correlation between nodes of traffic network on the spatial features,this paper proposes a traffic speed prediction model based on the combination of graph attention network with self-adaptive adjacency matrix(SAdpGAT)and bidirectional gated recurrent unit(BiGRU).First-ly,the model introduces graph attention network(GAT)to extract the spatial features of real road network and potential road network respectively in spatial ***,the spatial features are input into BiGRU to extract the time series ***,the prediction results of the real road network and the potential road network are connected to generate the final prediction results of the *** experimental results show that the prediction accuracy of the proposed model is im-proved obviously on METR-LA and PEMS-BAY datasets,which proves the advantages of the pro-posed spatial-temporal model in traffic speed prediction.

关键词： traffic speed prediction spatial-temporal correlation self-adaptive adjacency ma-trix graph attention network(GAT) bidirectional gated recurrent unit(BiGRU)