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Effect of sintering temperature and holding time on structure and properties of Li_(1.5)Ga_(0.5)Ti_(1.5)(PO_4)_(3)electrolyte with fast ionic conductivity
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作者 Yin-yi LUO Hao-zhang LIANG +6 位作者 Ping ZHANG Lei HAN Qian ZHANG Li-dan LIU Zhi-wei LUO Tian-xiang NING An-xian LU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2959-2971,共13页
Li_(1.5)Ga_(0.5)Ti_(1.5)PO_(4))_(3)(LGTP)is recognized as a promising solid electrolyte material for lithium ions.In this work,LGTP solid electrolyte materials were prepared under different process conditions to explo... Li_(1.5)Ga_(0.5)Ti_(1.5)PO_(4))_(3)(LGTP)is recognized as a promising solid electrolyte material for lithium ions.In this work,LGTP solid electrolyte materials were prepared under different process conditions to explore the effects of sintering temperature and holding time on relative density,phase composition,microstructure,bulk conductivity,and total conductivity.In the impedance test under frequency of 1-10^(6) Hz,the bulk conductivity of the samples increased with increasing sintering temperature,and the total conductivity first increased and then decreased.SEM results showed that the average grain size in the ceramics was controlled by the sintering temperature,which increased from(0.54±0.01)μm to(1.21±0.01)μm when the temperature changed from 750 to 950°C.The relative density of the ceramics increased and then decreased with increasing temperature as the porosity increased.The holding time had little effect on the grain size growth or sample density,but an extended holding time resulted in crack generation that served to reduce the conductivity of the solid electrolyte. 展开更多
关键词 sintering temperature holding time CONDUCTIVITY cracks solid-state electrolyte
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Formation environment and hydrocarbon potential of the Paleogene Enping Formation coal measures in the ZhuⅠDepression of northern South China Sea
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作者 Yuting Yin Lei Lan +5 位作者 Dongdong Wang Ying Chen Yan Liu Youchuan Li Zengxue Li Jiamin Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第4期119-135,共17页
The coal-measure source rock in the Chinese sea area plays a significant role as a hydrocarbon source rock,with its genetic environment,development and distribution,and hydrocarbon generation potential serving as esse... The coal-measure source rock in the Chinese sea area plays a significant role as a hydrocarbon source rock,with its genetic environment,development and distribution,and hydrocarbon generation potential serving as essential factors for the exploration of coal-type oil and gas fields.This study focuses on the coal-measure source rock of the Paleogene Enping Formation in the ZhuⅠDepression,located in the northern South China Sea.The main geological insights obtained are as follows.The coal measures of the Enping Formation are developed in a warm and wet tropical-subtropical climate.The development environment of the coal-measure source rock in the Enping Formation includes the braided river delta upper plain peat swamp,characterized by dry forest swamp coal facies with relatively thick coal seams and a small number of layers.The braided river delta lower plain swamp-interdistributary bay of braided river delta front represents a forest edge-wetland herbaceous swamp coal facies with numerous layers of thin coal seams and poor stability.The shore swamp corresponds to an open water swamp coal facies with multiple layers of thin coal seams and poor stability.The organic matter abundance in the braided river delta upper plain is the highest,followed by the braided river delta lower plain-braided river delta front,and the shore-shallow lake.The organic matter type is predominantly typeⅡ1.Thermal evolution analysis suggests that the organic matter has progressed into a substantial oil generation stage.The hydrocarbon generation potential of the coal-measure source rock in the Enping Formation is the highest in the braided river delta upper plain,followed by the braided river delta lower plain-braided river delta front and the shore-shallow lake.Overall,this study proposes three organic facies in the coal-measure source rock of the Enping Formation:upper-plain swamp-dry forest swamp facies,lower plain-interdistributary bay-forest-herbaceous swamp facies,and lake swamp-herbaceous swamp facies. 展开更多
关键词 coal-measure source rock PALEOGENE genetic environment hydrocarbon generation characteristic zhuⅠDepression
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Inter-Fraction Analysis of One Week Hypo-Fractionation of Deep Inspiration Breath Hold (DIBH) Technique for Left Sided Breast Cancer Radiation Treatment
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作者 Ntombela N. Lethukuthula Mathuthu Manny Nyathi Mpumelelo 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2024年第3期41-52,共12页
The aim of this study was to investigate the inter-fraction variations, patient comfort and knowledge at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). The differences in set-up that occurred between treatme... The aim of this study was to investigate the inter-fraction variations, patient comfort and knowledge at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). The differences in set-up that occurred between treatment sessions for the left sided breast patients were observed and recorded. Measurements of routine set-up variation for 24 patients were performed by matching the cone beam computed tomography (CBCT) and the planning computed tomography (CT). Scans of all five fractions per patient were used to quantify the setup variations with standard deviation (SD) in all the three directions (anterior posterior, left right, and superior inferior). The patients DIBH comfort and knowledge was also evaluated. The average translational errors for the anterior posterior (AP, z), left-right (LR, x), and Superior-inferior (SI, y) directions were 0.40 cm, 0.40 cm, and 0.40 cm, respectively. The translation variation of the three directions showed statistical significance (P < 0.05). On comfort and knowledge investigation, among all participants, 80% moderately agreed that the therapist’s instructions for operating the deep inspiration breath hold (DIBH) technique were easy to understand, and 63.33% indicated that their comfort with the DIBH technique was neutral or average. The inter-fraction variations in patients with left-sided breast cancer were qualitatively analyzed. Significant shifts between CBCT and planning CT images were observed. The daily treatment verification could assist accurate dose delivery. 展开更多
关键词 Breast Cancer Deep Inspiration Breath hold Hypo-Fractionation Inter-Fraction
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Examining Zhang Peiji’s Translation of Beiying:A Study on the Representation of Zhu Ziqing’s Linguistic Style
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作者 Chen Liang Kou Zeyu Lu Silin 《Contemporary Social Sciences》 2024年第4期143-155,共13页
Based on Yan Fu’s translation norms of“faithfulness,expressiveness,and elegance”and Liu Miqing’s concept of aesthetic representation in translation,the present study employed a combined method of qualitative and q... Based on Yan Fu’s translation norms of“faithfulness,expressiveness,and elegance”and Liu Miqing’s concept of aesthetic representation in translation,the present study employed a combined method of qualitative and quantitative analysis to investigate the linguistic styles employed by Zhu Ziqing in his renowned prose Beiying.Then,using relevant corpora and self-designed Python software,we investigated whether Zhang Peiji,as a translator,has successfully reproduced the simplistic,emotional,and realistic linguistic characteristics in Zhu Ziqing’s prose from the perspectives of“faithfulness,expressiveness,and elegance.”The findings of the research indicate that by employing a dynamic imitative translation approach,Zhang Peiji has successfully enhanced the linguistic aesthetic qualities of the source text,striving to reflect the distinctive linguistic style of Zhu Ziqing. 展开更多
关键词 Beiying zhu Ziqing representation of linguistic style
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Characterization of Hydroxyapatite Extracted from Crab Shell Using the Hydrothermal Method with Varying Holding Times
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作者 Deni Fajar Fitriyana Rifky Ismail +2 位作者 Athanasius Priharyoto Bayuseno Januar Parlaungan Siregar Tezara Cionita 《Journal of Renewable Materials》 EI CAS 2024年第6期1145-1163,共19页
Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_... Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_(3) content,and have not been widely utilized in the synthesis of HA.This study aims to synthesize and analyze HA derived from crab shells using the hydrothermal method with different durations of holding time.This study utilized precipitated calcium carbonate(PCC)derived from crab shells.With a hydrothermal reactor set at 160℃ and varying holding times of 14(HA_14),16(HA_16),and 18(HA_18)h,a PCC and(NH4)2HPO4 mixture was used to synthesize HA.The synthesis results were analyzed using scanning electron microscopy(SEM),fourier transform infrared spectroscopy(FTIR),and X-ray diffraction(XRD)tests.This study has accomplished the synthesis of HA from crab shells.Nonetheless,the final product of synthesis still contained CaCO_(3) as an impurity.The prolonged hydrothermal holding time of 14 to 18 h resulted in a reduction of impurities while increasing the percentage of crystal weight and crystallite size of HA.Specimen CH_18 is the best-quality product generated in this study.This specimen produced HA with the highest percentage of crystal weight and crystallite size compared to the other specimens.Furthermore,specimen CH_18 exhibited the lowest concentration of impurities.The Ca/P ratio in this specimen was also the closest to 1.67.The Ca/P ratio,crystallite size,and crystal weight percentage of this specimen are 1.54,19.06 nm,and 99.1%,respectively. 展开更多
关键词 HYDROXYAPATITE crab shells CaCO_(3) HYDROTHERMAL holding time
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Application of a 2 Parameter Weibull Distribution in Modeling of State Holding Time in HIV/AIDS Transition Dynamics
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作者 Nahashon Mwirigi 《Open Journal of Modelling and Simulation》 2024年第4期130-158,共29页
This study investigates the application of the two-parameter Weibull distribution in modeling state holding times within HIV/AIDS progression dynamics. By comparing the performance of the Weibull-based Accelerated Fai... This study investigates the application of the two-parameter Weibull distribution in modeling state holding times within HIV/AIDS progression dynamics. By comparing the performance of the Weibull-based Accelerated Failure Time (AFT) model, Cox Proportional Hazards model, and Survival model, we assess the effectiveness of these models in capturing survival rates across varying gender, age groups, and treatment categories. Simulated data was used to fit the models, with model identification criteria (AIC, BIC, and R2) applied for evaluation. Results indicate that the AFT model is particularly sensitive to interaction terms, showing significant effects for older age groups (50 - 60 years) and treatment interaction, while the Cox model provides a more stable fit across all age groups. The Survival model displayed variability, with its performance diminishing when interaction terms were introduced, particularly in older age groups. Overall, while the AFT model captures the complexities of interactions in the data, the Cox model’s stability suggests it may be better suited for general analyses without strong interaction effects. The findings highlight the importance of model selection in survival analysis, especially in complex disease progression scenarios like HIV/AIDS. 展开更多
关键词 Weibull Distribution AFT Model Cox Proportional Hazards HIV/AIDS State holding Time Survival Analysis
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Dust-Holding Capacity and Bio-Chemical Changes of Plant Species Growing in an Around Opencast Mining Area of Bundelkhand Region of Uttar Pradesh, India
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作者 Priyanka Singh Amit Pal 《American Journal of Plant Sciences》 CAS 2024年第8期677-698,共22页
The present study has been carried out on a total of 50 available plant species to assess their dust-capturing capacity and biochemical performances in and around open cast granite mine areas of Jhansi district and Bu... The present study has been carried out on a total of 50 available plant species to assess their dust-capturing capacity and biochemical performances in and around open cast granite mine areas of Jhansi district and Bundelkhand University campus treated as control site. Plant species existing under a polluted environment for a long time may be considered as potentially resistant species and recommended for green belt design in mining areas, especially to cope with dust pollution. Results showed the pollution level, especially of mining-originated dust particles holding capacity of leaves and effects of different biochemical parameters (Total Chlorophyll, Protein and Carotenoid) of existing plant species both from mining areas as well as from Bundelkhand University campus. Based on their performances, Tectona grandis L., Ficus hispida L., Calotropis procera Aiton., Butea monosperma Lam. and Ficus benghalensis L., etc. are highly tolerant species while Ficus infectoria L., Artocarpus heterophyllus Lam., Ipomoea purpurea L., Allianthus excelsa Roxb. and Bauhinia variegata L. are intermediate tolerant species. T. grandis had shown the highest dust-holding capacity (2.566 ± 0.0004 mg/cm2) whereas Albizia procera (0.018 ± 0.0002 mg/cm2) was found to be the lowest dust-holding capacity. Our findings also showed that the T. grandis and F. hispida have significant dust deposition with minimal effect of dust on their leaf chlorophyll (17.447 ± 0.019 mg/g and 14.703 ± 0.201 mg/g), protein (0.699 ± 0.001 mg/g and 0.604 ± 0.002 mg/g) and carotenoid (0.372 ± 0.003 mg/g and 0.354 ± 0.003 mg/g) content respectively among all selected plant species. Therefore, in the present investigation, plant species with high tolerance to high dust-holding capacity on their leaf surfaces are preferable for green corridors as open cast granite mines and their adjacent areas. 展开更多
关键词 Bundelkhand Region Biochemical Changes Dust-holding Capacity Chlorophyll Content Open Cast Granite Mining
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Zhu Fan Zhi and the Maritime Road of Aromatic Medicine in the Song Dynasty 被引量:1
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作者 YU Zhilin ZHANG Yuan 《Chinese Medicine and Culture》 2023年第4期349-356,共8页
Zhao Rukuo's Zhu Fan Zhi in the Southern Song dynasty was the first book in the history of China to systematically describe the “Maritime Silk Road”, recording the geography, products, customs, trade, etc. of mo... Zhao Rukuo's Zhu Fan Zhi in the Southern Song dynasty was the first book in the history of China to systematically describe the “Maritime Silk Road”, recording the geography, products, customs, trade, etc. of more than 50 foreign countries and regions. The book included a large amount of medical literature, introducing medical customs and the production of drugs in various places, as well as the efficacy of some medicine. These materials are of unique value for understanding the medicine trade in the Song dynasty, and even the medical culture along the “Maritime Road of Aromatic Medicine”. 展开更多
关键词 Aromatic medicine Zhao Rukuo zhu Fan Zhi
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An Interview with Mr.Wang Zhukang,Chairman of Orient International(Holding)Co.Ltd.
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《China's Foreign Trade》 1998年第8期2-4,共3页
Theyear1997canbecaledanexperimentalyearfortheOrientInternational(Holding)Co.Ltd..OnMarch28,1997,theOrientI... Theyear1997canbecaledanexperimentalyearfortheOrientInternational(Holding)Co.Ltd..OnMarch28,1997,theOrientInternational(Hol... 展开更多
关键词 Mr.Wang zhukang Chairman INTERVIEW AN holding)Co.Ltd
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一类酉Virasoro顶点算子代数扩张的Zhu代数
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作者 程存广 《理论数学》 2023年第9期2572-2577,共6页
本文主要研究一类酉Virasoro顶点算子代数扩张的Zhu代数。Zhu在博士论文中证明了顶点算子代数的不可约模和顶点算子代数相应的Zhu代数的不可约模有一一对应关系,因此本文将通过其不可约模决定Zhu代数。
关键词 Virasoro顶点算子代数 扩张 zhu代数
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Differences of tuffaceous components dissolution and their impact on physical properties in sandstone reservoirs: A case study on Paleogene Wenchang Formation in Huizhou-Lufeng area, Zhu I Depression, Pearl River Mouth Basin, China
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作者 JIN Zihao YUAN Guanghui +4 位作者 ZHANG Xiangtao CAO Yingchang DING Lin LI Xiaoyan FU Xiaohan 《Petroleum Exploration and Development》 2023年第1期111-124,共14页
The element geochemical characteristics and diagenetic alteration products of tuffaceous components in sandstone reservoirs of Paleogene Wenchang Formation in typical subsags of the Huizhou-Lufeng area of the Zhu I De... The element geochemical characteristics and diagenetic alteration products of tuffaceous components in sandstone reservoirs of Paleogene Wenchang Formation in typical subsags of the Huizhou-Lufeng area of the Zhu I Depression,Pearl River Mouth Basin,were identified through microscopic analysis and quantitative analysis of main and trace elements.The impacts of dissolution of different tuffaceous components on physical properties of reservoirs were discussed through quantitative characterization of reservoir physical properties.The results show that there are mainly four types of tuffaceous components in the study area,which are acidic,intermediate,basic and alkaline tuffaceous components.The acidic tuffaceous components evolved in a process of strong alteration and weak dissolution of alteration products,with a large amount of kaolinite precipitated during alteration to disenable the improvement of porosity and permeability.The intermediate and alkaline tuffaceous components evolved in a process of strong dissolution of tuffaceous components and strong alteration of residual tuffaceous components;the dissolution of tuffaceous components created intergranular pores,but the alteration products such as autogenic quartz,apatite and illite deteriorated the pore structure;ultimately,the dissolution of tuffaceous components resulted in the increase of porosity but no increase of permeability of the reservoir.The basic tuffaceous components dominantly evolved in a process of dissolution of tuffaceous components to strong dissolution of alteration products;both tuffaceous components between particles and laumontite generated from alteration can be strongly dissolved to create pores;thus,the dissolution of tuffaceous components can significantly increase the physical properties of the reservoir. 展开更多
关键词 zhu I Depression Huizhou Sag Lufeng Sag tuffaceous component DISSOLUTION physical property response Paleogene Wenchang Formation
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Nail Holding Performance of Self-Tapping Screws on Masson Pine and Chinese Fir Dimension Lumbers
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作者 De Li Bengang Zhang +7 位作者 Yuan Tu Guoming Xiao Meifen Tian Xiaoxue Xu Xiao Zhong Qiaoyan Zhang Zhigang Wu Jiankun Liang 《Journal of Renewable Materials》 EI 2023年第10期3725-3738,共14页
Screw connection is a type most commonly applied to timber structures.As important commercial tree species in China,Masson pine and Chinese fir have the potential to prepare wood structures.In this study,the effects o... Screw connection is a type most commonly applied to timber structures.As important commercial tree species in China,Masson pine and Chinese fir have the potential to prepare wood structures.In this study,the effects of the diameter of the self-tapping screw and the guiding bores on the nail holding performance on different sections of Masson pine and Chinese fir dimension lumbers were mainly explored.The results showed that:(1)The nail holding strength of the tangential section was the maximum,followed by that of the radial section,and that of the cross section was the minimum.(2)The nail holding strength of Masson pine was higher than that of Chinese fir.(3)The nail holding strength grew with the increase in the diameter of self-tapping screws,but a large diameter would lead to plastic cracking of the timber,thus further affecting the nail holding strength.Masson pine and Chinese fir reached the maximum nail holding strength when the diameter of self-tapping screws was 3.5 mm.(4)Under a large diameter of screws,prefabricated guiding bores could mitigate timber cracking and improve its nail holding strength.(5)Prefabricated guiding bores were more necessary for the screw connection of Masson pine.The results obtained could provide a scientific basis for the screw connection design of Masson pine and Chinese fir timber structures. 展开更多
关键词 Masson pine Chinese fir self-tapping screws nail holding performance
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Continuity and Change in Dao Yin:Comparing and Contrasting the Therapeutic Exercises in Yin Shu(The Book of Pulling,c.2nd Century BCE)and Zhu Bing Yuan Hou Lun(Treatise on the Origins and Manifestations of Various Diseases,610 CE)
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作者 Dolly Yang 《Chinese Medicine and Culture》 2023年第1期76-87,共12页
The manuscript Yin Shu(The Book of Pulling),excavated from Zhangjiashan Han Tomb No.247,is the earliest surviving text on therapeutic exercise known as Dao Yin(lit.guiding and pulling).Discovered in 1983,this Dao Yin ... The manuscript Yin Shu(The Book of Pulling),excavated from Zhangjiashan Han Tomb No.247,is the earliest surviving text on therapeutic exercise known as Dao Yin(lit.guiding and pulling).Discovered in 1983,this Dao Yin text,together with the drawings of 44 figures performing“guiding and pulling”exercises found in the Mawangdui Han Tomb in 1974,are of great significance to the study of the early history of Dao Yin.Prior to these discoveries,researchers into Dao Yin relied mainly on material found in the Dao Zang(the Daoist Canon),compiled in 1145.This led to their conclusion that Dao Yin was essentially Daoist.The development of Dao Yin reached its zenith during the Sui Dynasty(581–618 CE),when it became one of the three medical departments at the imperial medical education institution.As part of the medical reform of the second Sui Emperor,Yang Di,Dao Yin became the treatment of choice,and the employment of a large number of Dao Yin specialists to the Sui court transformed the state medical service.The compilation of Zhu Bing Yuan Hou Lun(Treatise on the Origins and Manifestations of Various Diseases)under Yang Di’s decree,incorporated an abundance of resources on Dao Yin,enabling physicians to potentially“prescribe”Dao Yin to their patients.Situating both Yin Shu and Zhu Bing Yuan Hou Lun in their social and historical contexts,this article analyses their editorial treatments,examines their different objectives,styles,and readerships,and compares the various exercises described in the two texts.It emphasizes the fact that over a period of nearly a thousand years,from the late Warring States(475–221 BCE)to the Sui and Tang periods,Dao Yin was an important medical practice,culminating in its institutionalization by the Sui government. 展开更多
关键词 Dao Yin Early and medieval Chinese medicine Therapeutic exercise Yin Shu zhu Bing Yuan Hou Lun
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The Topological Deformation of Brave Female Images in Shakespeare’s Plays:A Case Study of Juliet,Portia and Cordelia in Zhu Shenghao’s Translation
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作者 YANG Fei-ran 《Journal of Literature and Art Studies》 2023年第4期237-247,共11页
The female images in Shakespeare’s plays are diverse and colorful,showing the typological deformation value of topology.The brave female women in his plays,such as Juliet in Romeo and Juliet,Portia in The Merchant of... The female images in Shakespeare’s plays are diverse and colorful,showing the typological deformation value of topology.The brave female women in his plays,such as Juliet in Romeo and Juliet,Portia in The Merchant of Venice,Cordelia in King Lear,are the same type and equivalent topological deformation.In artistic terms,the three women of the same type with their own characteristics are the deformed topological space under the principle of equivalence,which is embodied vividly in the source text.This thesis purposed to investigate whether the translation of Zhu Shenghao also reflected the equivalent deformation of Shakespeare’s original text.This study texts the validity of the target text from the source text,proves the evaluation mechanism and function of topology in the process of translation and explains how the translation is equivalent to the original. 展开更多
关键词 SHAKESPEARE topological deformation zhu Shenghao Juliet PORTIA Cordelia
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CAFIU holds a Webinar on the New Vision of China-Bosnia and Herzegovina Cooperation and Role of Civil Society
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《International Understanding》 2023年第1期24-25,共2页
On January 17,the Chinese Association for International Understanding(CAFIU)and the Association of Bosnia-China Friendship co-hosted the webinar themed New Vision of China-Bosnia and Herzegovina Cooperation and Role o... On January 17,the Chinese Association for International Understanding(CAFIU)and the Association of Bosnia-China Friendship co-hosted the webinar themed New Vision of China-Bosnia and Herzegovina Cooperation and Role of Civil Society. 展开更多
关键词 holds BOS EGO
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China holds the secretariat of ISO/TC 341 on heat supply network
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《China Standardization》 2023年第3期13-13,共1页
The inauguration of the secretariat of ISO/TC 341,Heat supply net work,was held in Beijing on April 11.China Urban Construction Design&Research Institute,a subordinate enterprise of China Construction Technology C... The inauguration of the secretariat of ISO/TC 341,Heat supply net work,was held in Beijing on April 11.China Urban Construction Design&Research Institute,a subordinate enterprise of China Construction Technology Consulting Co.,Ltd.(CCTC),holds the secret ariat,which is China’s first ISO secretariat for standardization in the field of housing and urban-rural development. 展开更多
关键词 ISO/TC holds NETWORK
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滇中地区主要森林凋落物有效截留量及其影响因素 被引量:2
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作者 王平 李璐杉 +1 位作者 丁智强 李玉辉 《水土保持研究》 CSCD 北大核心 2024年第3期213-221,229,共10页
[目的]研究滇中地区主要森林类型凋落物有效截留量差异及其影响因素,为该地未来植被恢复和森林管理提供科学支撑。[方法]利用样方调查法、烘干法和浸泡法分析了昆明市双河—磨南德水源林自然保护区内的地带性次生常绿阔叶林(SF)、针阔... [目的]研究滇中地区主要森林类型凋落物有效截留量差异及其影响因素,为该地未来植被恢复和森林管理提供科学支撑。[方法]利用样方调查法、烘干法和浸泡法分析了昆明市双河—磨南德水源林自然保护区内的地带性次生常绿阔叶林(SF)、针阔混交林(TF)、旱冬瓜林(ACF)、华山松林(PA)、成熟云南松林(OPY)、幼龄云南松林(YPY)、银荆林(AD)7种主要森林类型凋落物未分解层(OL)和半分解层(OF)的有效截留量及其影响因素。[结果](1) 7种森林类型凋落物厚度为2.06~7.57 cm,其中OL层1.10~4.30 cm, OF层0.83~3.93 cm,凋落物层厚度排序为TF>ACF>PA>OPY>SF>AD>YPY,凋落物蓄积量为4.75~17.45 t/hm^(2),其中OL层占比为32.02%~62.48%,OF层占比为37.52%~67.98%,凋落物层蓄积量排序为TF>PA>SF>OPY>ACF>AD>YPY。(2)凋落物最大持水率为115.3%~170.7%,初始吸水速率为3.65~5.62 g/(g·h),凋落物持水率和浸水时间的关系可用对数函数y=aln(x)+b表示,吸水速率与浸水时间可用幂函数y=kt~n表示。(3)凋落物最大持水量为7.05~32.19 t/hm^(2),排序为PA>TF>SF>OPY>ACF>AD>YPY,有效截留量为5.45~25.34 t/hm^(2),以TF最高(25.34t/hm^(2)),PA(24.99 t/hm^(2))和SF(24.62 t/hm^(2))次之,YPY最低(5.45t/hm^(2)),影响有效截留量的场地特征主要为蓄积量、自然含水率、分解强度以及厚度,影响有效截留量的水动力过程主要是最大失水量、前6.0 h平均吸水速率和前2.0 h平均吸水速率。[结论]滇中地区未来植树造林应以针阔混交林为主,注重对地带性次生常绿阔叶林的保育,采取辅助自然更新的措施促进人工纯林向混交林演化,同时减少踩踏、收集凋落物等人类活动的干扰,从而增加森林生态系统凋落物的水源涵养能力。 展开更多
关键词 凋落物 主要森林类型 持水特性 有效截留量 滇中地区
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复合型水性丙烯酸树脂乳液的制备和性能 被引量:1
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作者 王利敏 宋晓宇 +1 位作者 程森祥 陈彤 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第3期39-47,共9页
采用低玻璃化转变温度、高分子量的丙烯酸树脂乳液与高玻璃化转变温度、低分子量的丙烯酸树脂分散体混合的方式,制备了无交联剂水性丙烯酸树脂复合乳液,用于彩印包装纸与塑料薄膜的热复合。以丙烯酸、丙烯酸丁酯、苯乙烯、丙烯酸羟乙酯... 采用低玻璃化转变温度、高分子量的丙烯酸树脂乳液与高玻璃化转变温度、低分子量的丙烯酸树脂分散体混合的方式,制备了无交联剂水性丙烯酸树脂复合乳液,用于彩印包装纸与塑料薄膜的热复合。以丙烯酸、丙烯酸丁酯、苯乙烯、丙烯酸羟乙酯等为原料,采用种子乳液聚合法制备了相对分子质量(1.48~1.84)×10^(5)、玻璃化转变温度(T_(g))﹣20~﹣40℃的丙烯酸酯乳液。以丙烯酸、丙烯酸丁酯、苯乙烯、α-甲基苯乙烯、马来酸单酯等为原料,采用本体聚合法制备了相对分子质量(1.34~1.65)×10^(4)、T_(g) 20~45℃、软化点80~105℃的固体树脂,进一步采用自乳化方法将固体树脂制备成树脂水分散体。考察了不同Tg的丙烯酸酯乳液与水分散体以不同比例混配后的乳液混合体的性能。研究结果表明,T_(g)为﹣27.6℃的丙烯酸酯乳液与Tg为28.2℃固体树脂的分散体以质量比8:2混合后,用于PET膜-黑色印刷纸的热复合,剥离强度达到5.6 N/25 mm,持粘性达270 h,可以充分满足覆膜材料的附着力和耐压纹等性能要求。 展开更多
关键词 丙烯酸树脂乳液 树脂水分散体 热覆膜 剥离强度 持粘性
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数据资源持有权的法律解释 被引量:6
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作者 于海纯 陈润恺 《科技与法律(中英文)》 CSSCI 2024年第2期21-30,共10页
在大数据和人工智能技术的推动下,数据资源从单纯的信息载体转变为独立的价值来源,开始出现财产属性。但其所具有的非排他性、技术依附性等特征使得传统的信息权益与权利保护范式难以适用。数据资源的价值源于对数据的控制状态,这并非... 在大数据和人工智能技术的推动下,数据资源从单纯的信息载体转变为独立的价值来源,开始出现财产属性。但其所具有的非排他性、技术依附性等特征使得传统的信息权益与权利保护范式难以适用。数据资源的价值源于对数据的控制状态,这并非实体权利。数据资源持有权在法律上应解释为“持有主体合法控制数据资源并免受非法干扰和攻击的利益”。持有利益受侵害所造成的损失属于纯粹经济损失,应采用行为主义保护模式,通过侵权法一般条款进行救济。持有主体则应根据具体数据类型遵守相应的行为标准。此外,个人信息数据的相关规则是基于风险防范的考量,对数据所携带信息采取保护措施,个人信息主体属于数据来源者而非数据资源持有主体。 展开更多
关键词 数据产权 数据资源持有权 利益保护 行为主义
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数字经济与新型城镇化:作用机制和门槛效应 被引量:6
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作者 韩刚 李润琴 《工业技术经济》 CSSCI 北大核心 2024年第1期21-30,共10页
随着新一代信息技术蓬勃发展,数字经济无疑是实现新型城镇化的必然选择。本文基于2013~2022年30个省(区、市)的面板数据,通过构造数字经济发展水平指数与新型城镇化水平指数研究数字经济对新型城镇化的影响,并引入技术创新和碳减排分析... 随着新一代信息技术蓬勃发展,数字经济无疑是实现新型城镇化的必然选择。本文基于2013~2022年30个省(区、市)的面板数据,通过构造数字经济发展水平指数与新型城镇化水平指数研究数字经济对新型城镇化的影响,并引入技术创新和碳减排分析数字经济驱动新型城镇化的作用机制。研究发现,数字经济对我国新型城镇化的建设具有明显的推动作用,在新型城镇化水平低的省(区、市)与中部地区提升效果更明显;机制分析表明,技术创新和碳减排是数字经济促进新型城镇化的重要传导机制;通过进一步的门槛检验发现,数字经济对新型城镇化的推动作用因产业结构的不断升级呈现出先正后负的特征。研究结论可为加速释放数字经济红利,推动新型城镇化发展提供经验证据和政策启示。 展开更多
关键词 数字经济 新型城镇化 技术创新 碳减排 产业结构 门槛效应
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