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Chinese Chemical Letters 2008年第6期19卷 720-724页

作者： chun xi Zhai Hai Ning Gu Da Yong Sang Juan Tian Qi Zhong Zhou Department of Chemistry Zhejiang University Hangzhou 310027 China

The deaggregating ability of β-CD and α-CD against the aggregated n-hexadecyl β-naphthoate （A16） and n-dodecyl β-naphthoate （A12） depended not only on the aggregating tendency of A16 and A12 but also on the initial concentration of the aggregated A16 or A12. The inclusive ability of β-CD with the substrates is greater than that of α-CD under hydrophobiclipophilic interaction.

关键词： Deaggregation Aggregation Coaggregation Critical aggregating concentration

Abrupt change of winter temperature over the Mongolian Plateau during 1961-2017

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Journal of Mountain Science 2023年第4期20卷 996-1009页

作者： xiA Ying-ying chun xi DAN Dan LIU Hong-yu ZHOU Hai-jun WAN Zhi-qiang Inner Mongolia Restoration Engineering Laboratory of Wetland Eco-environment System Inner Mongolia Normal UniversityHohhot010022China Key Laboratory of Mongolian Plateau’s Climate System Inner Mongolia Normal UniversityHohhot010022China College of Geographical Science Inner Mongolia Normal UniversityHohhot010022China College of Resources and Environment Baotou Teachers’CollegeBaotou014030China

Studying the abrupt change of winter temperature(ACWT)over the Mongolian Plateau(MP,including Inner Mongolia Autonomous Region and State of Mongolia)is of great significance for understanding the spatiotemporal distribution of temperature and the mechanism of global climate *** temperature data during 1961–2017was collected,and the abrupt change point was determined by the Mann–Kendall test and sliding ttest,to analyze the characteristics and causes of *** results showed that(a)The winter temperature has rapidly increased with a trend of 0.41℃/10a,which was significantly higher than that of the rest area of Chinese mainland,indicating that climate change in the MP was more sensitive to global warming.(b)The abrupt change point occurred in 1988,with temperature of-15.5℃and-14.1℃before and after abrupt change,*** ACWT in 50°N was 1–3 years later than that in 40°N,and the isotherms of different temperatures moved northward by 10–200 km,especially-16℃isotherms moved approximately 200 km northward after 1988.(c)The Arctic Oscillation(AO)and Mongolian High(MH)anomaly affects winter temperature over the *** the AO is unusually strong,the MH and East Asian winter monsoon are weak,and southerly winds prevail in most regions,which is not conducive to the cold air developing southward,leading to higher winter temperature in the ***,abnormally northerly winds prevail and temperature is ***,the abrupt change time of AO occurred in 1987 before winter *** shows that the AO indirectly causes winter temperatures to rise by influencing the MH and is also the main driving factor of ACWT.

关键词： Abrupt temperature change Spatiotemporal distribution Arctic Oscillation Winter temperature Mongolian Plateau

Inferring playback rate and rate resets of P2P video streaming transmissions by piecewise line envelope approximation

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The Journal of China Universities of Posts and Telecommunications 2009年第2期16卷 58-62,79页

作者： LI chun-xi CHEN Chang-jia School of Electronics and Information Engineering,Beijing Jiaotong University,Beijing 100044,China [a]School of Electronics and Information Engineering Beijing Jiaotong University Beijing 100044 China

Conventionally, P2P video is regarded as CBR traffic. However, our measurements have shown that the rate reset cannot be neglected in a practical IPTV system because each rate reset often leads to performance degradation. Thus, addressing the problem of inferring playback rate and rate reset in a P2P video system is significant. In this article, an algorithm termed piecewise linear envelope approximation （PLEA） is proposed, in which a follow-up time is introduced to smooth rate fluctuations in a small time scale and to adapt rate jumps in a large time scale automatically. With the PLEA algorithm, discontinuity introduced by blind segmentations adopted by current methods is avoided. Furthermore, unlike existing algorithms in which both segmentation and combinations are performed in multiple runs, only a single computation path is involved in the PLEA algorithm. This makes PLEA algorithm amenable to implementation of low complexity by either software or hardware. Both theoretical analysis and experiment based on measured data show that the PLEA outperforms existing algorithms based on segmentation.

关键词： P2P video playback rate rate reset convex hull linear program

Magnetocaloric effect of Pr_2Fe_(17-x)Mn_x alloys

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Rare Metals 2014年第5期33卷 552-555页

作者： xi-chun Zhong Zhong-Wu Liu De-Chang Zeng Karl A.Gschneidner Jr. Vitalij K.Pecharsky School of Materials Science and Engineering South China University of Technology Ames Laboratory U.S.Department of Energy and Department of Materials Science and Engineering Iowa State University

Polycrystalline Pr2Fe17-xMnx（x = 0, 1, and 2）alloys were studied by X-ray diffraction（XRD）, heat capacity, ac susceptibility, and isothermal magnetization measurements. All the alloys adopt the rhombohedral Th2Zn17-type structure. The Curie temperature increases from 283 K at x = 0 to 294 K at x = 1, and then decreases to 285 K at x = 2. The magnetic phase transition at the Curie temperature is a typical second-order paramagnetic–ferromagnetic transition. For an applied field change from0 to 5 T, the maximum-△SM for Pr2Fe17-xMnxalloys with x = 0, 1, and 2 are 5.66, 5.07, and 4.31 J·kg^-1·K^-1,respectively. The refrigerant capacity（RC） values range from 458 to 364 J·kg^-1, which is about 70 %–89 % that of Gd. The large, near room temperature △SM and RC values,chemical stability, and a high performance-to-cost ratio make Pr2Fe17-xMnxalloys be selectable materials for room temperature magnetic refrigeration applications.

关键词： Pr2Fe17-xMnx alloys Magnetocaloric effect Magnetic entropy change

Numerical investigation of the interaction of the turbulent dual-jet and acoustic propagation

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Chinese Physics B 2017年第2期26卷 294-304页

作者： Yi-Ming Li Bao-Kuan Li Feng-Sheng Qi xi-chun Wang School of Metallurgy Northeastern University Shenyang 110819 China

In order to study the interaction between two independent jets, a three-dimensional（3D） transient mathematical model is developed to investigate the flow field and acoustic properties of the two-stream jets. The results are compared with those of the single-stream jet at Mach number 0.9 and Reynolds number 3600. The large eddy simulation（LES） with dynamic Smagorinsky sub-grid scale（SGS） approach is used to simulate the turbulent jet flow structure. The acoustic field is evaluated by the Ffowcs Williams–Hawkings（FW-H） integral equation. Considering the compressibility of high-speed gas jets, the density-based explicit formulation is adopted to solve the governing equations. Meanwhile, the viscosity is approximated by using the Sutherland kinetic theory. The predicted flow characteristics as well as the acoustic properties show that they are in good agreement with the existing experimental and numerical results under the same flow conditions available in the literature. The results indicate that the merging phenomenon of the dual-jet is triggered by the deflection mechanism of the Coanda effect, which sequentially introduces additional complexity and instability of flow structure. One of the main factors affecting the dual-jet merging is the aperture ratio, which has a direct influence on the potential core and surrounding flow fluctuation. The analysis on the noise pollution reveals that the potential core plays a fundamental role in noise emission while the additional mixing noise makes less contribution than the single jet noise. The overall sound pressure level（OASPL） profiles have a directive property, suggesting an approximate 25° deflection from the streamwise direction, however, shifting toward lateral direction of about 10° to 15° in the dual-jet. The conclusion obtained in this study can provide valuable data to guide the development of manufacturing-green technology in the multi-jet applications.

关键词： dual-jet jet entrainment acoustic characteristic Coanda effect

Two-Detector Arbitrary NtH^(-)Order HBT-Type Ghost Diffraction

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Chinese Physics Letters 2012年第1期29卷 126-129页

作者： CAO Bin ZHANG chun-xi OU Pan LIN Zhi-Li SUN Ming-Jie School of Instrumentation Science and Opto-electronics Engineering Beihang UniversityBeijing 100191

The imaging quality using two-detector arbitrary N th-order intensity correlation in optics is *** is theoretically demonstrated that with the order of intensity correlation N increases,the visibility of the retrieved image enhances promptly;and different n-fold intensity on one arm of the intensity correlation leads to different visibility,whereas the resolution is independent of N and *** numerical simulation results are shown to be consistent with our theoretical analysis ***,a particular imaging system of the two-detector N thorder Hanbury-Brown-Twiss(HBT)type ghost diffraction is conceived by using a slit as the object,the image quality by this type of ghost diffraction is *** experimental results coincide with our theoretical analysis.

关键词： ghost Ghost prompt

Recurrent paratesticular dedifferentiated iposarcoma after contralateral radical orchiectomy

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Asian Journal of Andrology 2018年第5期20卷 520-522页

作者： Jin Wang Yi-Peng Du Sheng-xian Li Jing-Hai Hu chun-xi Wang Department of Urology The First Hospital of Jilin University Changchun 130021 China Department of Anesthesiology The First Hospital of Jilin University Changchun 130021 China

Dear Editor, The concept of dedifferentiated liposarcoma （DDL） was first proposed by Evans in 1979.1 Liposarcomas, including DDL and well-differentiated liposarcoma （WDL）, occur most frequently in 50- to 70-year-old men within the retroperitoneum or extremities. DDL has a propensity for local recurrence, but distant metastasis is rare. Retroperitoneal DDL has a significantly worse prognosis than disease at other locations.2 As paratesticular DDL is a rare entity, clinicians need to differentiate it from other common scrotal neoplasms or swelling diseases.

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Effects of Root Pruning on Non-Hydraulic Root-Sourced Signal, Drought Tolerance and Water Use Efficiency of Winter Wheat

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Journal of Integrative Agriculture 2013年第6期12卷 989-998页

作者： MA Shou-chen LI Feng-min YANG Shen-jiao LI chun-xi XU Bing-cheng ZHANG Xu-cheng State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Ministry of Water Resources/Institute of Soil and Water Conservation Chinese Academy of Sciences School of Surveying and Land Information Engineering Henan Polytechnic University Key Laboratory of Efficient Utilization of Water in Dry Farming Gansu Province College of Life Science Henan Normal University

Two pot experiments were conducted to study the effects of root pruning at the stem elongation stage on non-hydraulic root-sourced signals （nHRS）, drought tolerance and water use efficiency of winter wheat （Triticum aestivum）. The root pruning significantly reduced the root weight of wheat, but had no effect on root/shoot ratio at the two tested stages. At booting stage, specific root respiration of root pruned plants was significantly higher than those with intact roots （1.06 and 0.94 mmol g-1 s-1, respectively）. The soil water content （SWC） at which nHRS for root pruned plants appeared was higher and terminated lower than for intact root plants, the threshold range of nHRS was markedly greater for root pruned plants （61.1-44.6% field water capacity） than for intact root plants （57.9-46.1% field water capacity）. At flowering stage, while there was no significant difference in specific root respiration. The SWCs at which nHRS appeared and terminated were both higher for root pruned plants than for intact root plants. The values of chlorophyll fluorescence parameters, i.e., the effective photosystem II quantum yield （F PS II ）, the maximum photochemical efficiency of PS II （F v /F m ）, coefficient of photochemical quenching （qP）, and coefficient of non-photochemical quenching （NPQ）, in root pruned plants were significantly higher than in intact root plants, 7 d after withholding of water. Root pruned plants had significantly higher water use efficiency （WUE） than intact root plants in well-watered and medium drought soil, but not in severe drought condition. In addition, root pruning had no significant effect on grain yield in well-watered and medium drought soil, but significantly decreased grain yield in severe drought condition. In conclusion, the current study showed that root pruning significantly altered nHRS sensitivity and improved WUE of winter wheat in well-watered and medium drought soil, but lowered drought tolerance of winter wheat in severe drought soil

关键词： winter wheat root pruning non-hydraulic root-sourced signal (nHRS) root activity drought tolerance

Law and Literature: Exploring the Intersection of Two Fields

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Journal of Literature and Art Studies 2023年第3期13卷 170-177页

作者： HU chun-xi Central South University of Forestry and Technology Institute of Political Science and LawHunan ProvinceChina

This article aims to explore the intersection of law and literature,analyzing their connections and ***,the article introduces the definitions and basic characteristics of law and literature,emphasizing their similarities and ***,the article discusses how literary works involve legal issues and how law becomes the subject and background of literary *** addition,the article studies the interaction between law and literature,exploring the impact of novels on legal practice,and how legal texts are rewritten and interpreted in literary ***,the article summarizes the relationship between law and literature and offers some prospects and reflections.

关键词： law literature intersection interaction influence

Frequency Modulation Induced by using the Linear Phase Modulation Method used in a Resonator Micro-optic Gyro

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Chinese Physics Letters 2012年第1期29卷 148-151页

作者： HONG Ling-Fei ZHANG chun-xi FENG Li-Shuang YU Huai-Yong LEI Ming School of Instrumentation Science and Opto-electronics Engineering and Key Laboratory of Micro-Nano Measurement-Manipulation and Physics(Ministry of EducationBeihang UniversityBeijing 100083

Resonator micro-optic gyro (R-MOG) sensing rotation angular-velocity is based on Sagnac *** present a frequency modulation (FM) induced by the analog triangle-waveform phase modulation (ATAW-PM) technique in an *** with the traditional serrodyne phase modulation or digital phase modulation methods,the proposed modulation technique has the intrinsic advantage in free of sweeping-back or step-effect induced pulse *** influence on dynamic range and resolution of the R-MOG by the parameters of analog trianglewaveform is theoretically *** are carried out on an R-MOG composed of an integrated optic resonator with a free spectral range (FSR) and a fitness (F) of 1.6GHz and 61,*** range of ±500 deg/s and bias drift of 0.6 deg/s over 1 h and 0.05 deg/s for 60 s are reliably obtained.

关键词： Resonator resonator triangle