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Influences of surface effects and large deformation on the resonant properties of ultrathin silicon nanocantilevers

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Chinese Physics B 2012年第1期21卷 363-373页

作者： Zhang Jia-Hong Li Min Gu Fang liu qing-quan Jiangsu Key Laboratory of Meteorological Observation and Information Processing Nanjing University of Information Science&TechnologyNanjing 210044China College of Math&Physics Nanjing University of Information Science&TechnologyNanjing 210044China

The purpose of the present work is to quantify the influences of the discrete nature, the surface effects, and the large deformation on the bending resonant properties of long and ultrathin （100） silicon nanocantilevers. We accomplish this by using an analytical semi-continuum Keating model within the framework of nonlinear, finite deformation kinematics. The semi-continuum model shows that the elastic behaviors of the silicon nanocantilevers are size-dependent and surface- dependent, which agrees well with the molecular dynamics results. It also indicates that the dominant effect on the fundamental resonant frequency shift of the silicon nanocantilever is adsorption-induced surface stress, followed by the discrete nature and surface reconstruction, whereas surface relaxation has the least effect. In particular, it is found that a large deformation tends to increase the nonlinear fundamental frequency of the silicon nanocantilever, depending not only on its size but also on the surface effects. Finally, the resonant frequency shifts due to the adsorption-induced surface stress predicted by the current model are quantitatively compared with those obtained from the experimental measurement and the other existing approach. It is noticed that the length-to-thickness ratio is the key parameter that correlates the deviations in the resonant frequencies predicted from the current model and the empirical formula.

关键词： resonant properties elastic properties surface effects silicon nanocantilevers

Effect of intercropping on maize grain yield and yield components

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Journal of Integrative Agriculture 2019年第8期18卷 1690-1700页

作者： HUANG Cheng-dong liu quan-qing LI Xiao-lin ZHANG Chao-chun College of Resources and Environmental Sciences China Agricultural University Beijing 100193 P.R.China Key Laboratory of Plant-Soil Interactions Ministry of Education China Agricultural University Beijing 100193 P.R.China Institute of Agricultural Resources & Environment Hebei Academy of Agricultural and Forestry Sciences Shijiazhuang 050051P.R.China

Smallholders in developing countries commonly use intercropping to produce crops with higher yield and value. Many intercropping studies have been conducted under experimental conditions, but few studies have been performed in farmers’ fields. We conducted a 4-year study using data from real farms to examine the relationships between yield and yield components of intercropped maize in the North China Plain. Three field experiments were conducted to compare the suitability of different maize varieties in intercropping. In the farm study, the grain yield of maize intercropped with watermelon was reduced by more than one third as compared to maize in wheat-maize double cropping, mainly due to lower ear density and lower 100-grain weight. Under real farm conditions, the yield of intercropped maize increased with increasing ear density and 100-grain weight, while yield of sole maize increased with increasing grain number per ear and 100-grain weight. In the field experiments, the maize cultivars commonly used in double cropping gave similar yields when grown in the intercropping system and their yields were closely related to ear density and 100-grain weight. Our results demonstrated that ear density, rather cultivar, was a key factor affecting the productivity of intercropped maize. Therefore,maintaining high ear density is a practical way for promoting productivity of maize in farmers’ intercropping practices.

关键词： maize ear density intercropping double cropping cultivars

A quasi single-phase model for debris flows and its comparison with a two-phase model

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Journal of Mountain Science 2018年第5期15卷 1071-1089页

作者： XIA Chun-chen LI Ji CAO Zhi-xian liu qing-quan HU Kai-heng State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Department of Mechanics School of Aerospace Engineering Beijing Institute of Technology Institute of Mountain Hazards and Environment Chinese Academy of Sciences

A depth-averaged quasi single-phase mixture model is proposed for debris flows over inclined bed slopes based on the shallow water hydrosediment-morphodynamic theory with multi grain sizes. The stresses due to fluctuations are incorporated based on analogy to turbulent flows, as estimated using the depth-averaged k-? turbulence model and a modification component. A fully conservative numerical algorithm, using wellbalanced slope limited centred scheme, is deployed to solve the governing equations. The present quasi single-phase model using four closure relationships for the bed shear stresses is evaluated against USGS experimental debris flow and compared with traditional quasi single-phase models and a recent physically enhanced two-phase model. It is found that the present quasi single-phase model performs much better than the traditional models, and is attractive in terms of computational cost while the two-phase model performs even better appreciably.

关键词： Debris flows Quasi single-phase mixturemodel Stresses due to fluctuations Well-balanced

Influence of Surface Effects on the Elastic Properties of Silicon Nanowires with Different Cross Sections

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Chinese Physics Letters 2011年第10期28卷 165-168页

作者： GU Fang ZHANG Jia-Hong XU Lin-Hua liu qing-quan LI Min College of Mathematics and Physics Nanjing University of Information Science and TechnologyNanjing 210044 College of Electronic and Information Engineering Nanjing University of Information Science and TechnologyNanjing 210044

Based on the anharmonic Keating model and the modified bending theory,an analytical semi-continuum atomistic lattice model is proposed for the size-dependent bending mechanical analysis of silicon nanowires(SiNWs)with different cross-sectional *** semi-continuum model proves that the elastic behavior of SiNWs is size-dependent and predicts softer or stiffer SiNWs which depend on the relaxation coefficient and the surface *** also shows that the size effects of the mechanical responses of SiNWs depend on not only surface effects but also the cross-sectional shapes of SiNWs.

关键词： nanowires bending size

Reduning Injection versus Neuraminidase Inhibitors in Treatment of Influenza:A Systematic Review and Meta-Analysis

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Chinese Journal of Integrative Medicine 2022年第11期28卷 1023-1031页

作者： ZHAO Guo-zhen LI Bo WANG Ya-fan GUO Shi-qi DU Yuan MA Qiu-xiao GUO Yu-hong liu qing-quan School of Clinical Medicine Beijing University of Chinese MedicineBeijing(100029)China Department of Emergency Beijing Hospital of Traditional Chinese MedicineCapital Medical UniversityBeijing(100010)China Beijing Evidence-Based Chinese Medicine Center Beijing(100010)China Beijing Institute of Chinese Medicine Beijing(100010)China School of Acupuncture-Moxibustion and Tuina Beijing University of Chinese MedicineBeijing(100029)China Department of Respiratory Xiyuan HospitalChina Academy of Chinese Medical SciencesBeijing(100700)China

Objective:To perform a systematic review to assess the effectiveness and safety of Reduning Injection versus neuraminidase inhibitors in treatment of ***:The MEDLINE,Embase,the Cochrane Central Register of Controlled Trials(CENTRAL),Chinese Bio-medical Literature and Retrieval System(Sinomed),China National Knowledge Infrastructure Database(CNKI),China Science and Technology Journal Database(VIP),Wanfang Data Knowledge Service Platform and *** were systematically searched from inception dates to May 2021 for randomized controlled trials(RCTs)exploring Reduning Injection alone or in combination with neuraminidase inhibitors in patients with *** analysis was performed using RevMan 5.4 and Stata *** qualities of the involved studies were assessed by the risk of bias according to the Cochrane *** evidence quality of each outcome was evaluated by GRADEpro ***:Twelve trials with 1,460 patients were *** included studies had a certain unclear or high risk of *** Injection appeared to be more effective in shortening the fever clearance time(MD:-16.20 h,95%CI:-19.40 to-12.99,7 trials,814 patients,I^(2)=94%,very low certainty),fever alleviation time(MD:-4.09 h,95%CI:-4.22 to-3.96,3 trials,366 patients,I^(2)=0%,low certainty),cough alleviation time(MD:-21.34 h,95%CI:-41.56 to-1.11,2 trials,228 patients,I^(2)=89%,very low certainty),fatigue alleviation time(MD:-31.83 h,95%CI:-36.88 to-26.77,2 trials,270 patients,I^(2)=0%,low certainty),sore throat alleviation time(MD:-28.66 h,95%CI:-32.23 to-25.10,1 trial,150 patients,low certainty),and improving the total effective rate(RR:1.15,95%CI:1.06 to 1.25,10 trials,1,074 patients,I^(2)=76%,very low certainty).Besides,Reduning Injection seemed generally ***:This study provided low or very low evidence indicating Reduning Injection may be effective in the treatment of influenza and might be *** rigorously designed studies are need

关键词： Chinese patent medicine Reduning Injection influenza meta-analysis systematic review

Respiratory Failure, Hepatic Failure, and Hemoptysis with Thrombocytopenia in a 79-Year-Old Man

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Chinese Medical Journal 2018年第12期131卷 1511-1512页

作者： Ya-Li Guo Yi-qing Jiao Li-Ya Guo Jian liu qing-quan liu Yu-Guang Wang Department of Respiratory Medicine Beijing Hospital of Traditional Chinese Medicine Affiliated to Capitar Medical University Beijing 100010 China

To the Editor： Langerhans cell histiocytosis （LCH） is a rare disease that usually occurs in the first two decades of life. Multisystem-LCH （MS-LCH） mainly affects youth. Bone, lung, and skin are the most common systems involved. Here, we report a case from China of MS-LCH in a 79-year-old patient with bone marrow, liver, spleen, and lung involvement, but without bone and skin involvement.

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Petrogenesis of granite from Xiaofan Mo deposit, Dabie Orogen

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Journal of Central South University 2018年第6期25卷 1489-1500页

作者： liu qing-quan SHAO Yong-jun ZHOU Ke-ping LI Yong-feng School of Resources and Safety Engineering Central South UniversityChangsha 410083China Key Laboratory of Metallogenic Prediction of Non-ferrous Metals and Geological Environment Monitoring Ministry of Education（School of Geosciences and Info-PhysicsCentral South University）Changsha 410083China Henan Provincial Non-Ferrous Metals Geological and Mineral Resources Bureau Zhengzhou 450016China ~ Central South University Press and Springer-Verlag GmbH Germanypart of Springer Nature 2018

The Mesozoic granitoids in the Dabie Orogen are of particular geological interest as indicators for Mesozoic lithospheric evolution because of their close association with porphyry Mo mineralization. Here, we present a study using petrogeochemistry data to constrain the petrogenesis of the Xiaofan granites in the Dabie Mo mineralization belt （DMB）, Henan Province, China. Field investigations show that the Xiaofan pluton mainly consists of porphyritic granite. The Xiaofan granites have high SiO2 contents of 74.29 wt%-76.07 wt% （average： 75.18 wt%）, A1203 contents of 11.66 wt%-12.83 wt% （average： 12.13 wt%）, and K20 contents of 5.37 wt%-7.90 wt% （average： 6.86 wt%） and low MgO （0.06 wt%-0.16 wt%）, TiO2 （0.09 wt%-0.10 wt%）, and P205 （0.047 wt%-0.103 wt%） contents. They are enriched in Rb, U, K and Hf but depleted in Ba, Nb, Ta, Sr and Ti. By geochemical and mineralogical features, we propose that the Xiaofan granites belong to A-type type granite and dominantly sourced from the crust. The granites from the Xiaofan Mo deposit may have formed in a post-collision extensional setting.

关键词： granite petrogenesis Xiaofan Mo deposit Dabie Orogen

Ferrocenyl building block constructing porous organic polymer for gas capture and methyl violet adsorption

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Journal of Central South University 2020年第4期27卷 1247-1261页

作者： HUANG Jin TAN Zhi-qiang SU Hui-min GUO Yi-wen liu Huan LIAO Bo liu qing-quan Schoolof Materials Science and Engineering Hunan University of Science and TechnologyXiangtan 411201China Hunan Provincial Key Lab of Advanced Materials for New Energy Storage and Conversion Xiangtan 411201China Hunan Provincial Key Lab of Controllable Preparation and Functional Application of Fine Polymers Xiangtan 411201China

Ferrocene-based porous organic polymer(FcPOP) was constructed with ferrocene and porphyrin derivatives as building blocks via Schiff-base coupling. FcPOP was well characterized, and exhibited good thermal stability, high porosity, microporous structure, and homogeneous pore size distribution. Ferrocene blocks with highly electron-rich characteristics endowed Fc POP with excellent adsorption capacity of CO2 and methyl violet. The kinetic study indicated adsorption of methyl violet onto FcPOP mainly complied with pesudo-second order model. The maximum adsorption capacity of FcPOP derived from Langmuir isotherm model reached up to 516 mg/g. More importantly, FcPOP could be easily regenerated and repeatedly employed for removal of methyl violet with high efficiency. Overall, FcPOP in the present study highlighted prospective applications in the field of gas capture and dyeing wastewater treatment.

关键词： ferrocene porous organic polymer gas capture dyeing wastewater

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中国古典美学的生命精神

社会科学家 2005年第5期20卷 18-21页

作者：柳清泉莱阳农学院人文与公共管理学院山东莱阳265200

中国古典美学蕴涵着深厚的生命意蕴。中国古典美学的六大思潮———儒家美学、道家美学、周易美学、玄学美学、禅宗美学和明清人性论美学都贯穿着一个共同的思想:生命即美。透过艳丽之极的现象之美,中国古典美学渗透着深刻的人性内容和... 详细信息

中国古典美学蕴涵着深厚的生命意蕴。中国古典美学的六大思潮———儒家美学、道家美学、周易美学、玄学美学、禅宗美学和明清人性论美学都贯穿着一个共同的思想:生命即美。透过艳丽之极的现象之美,中国古典美学渗透着深刻的人性内容和高尚的人格精神,富有一种深邃的生命意味。

关键词：美生命中国古典美学生命美学