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The potential for an old-growth forest to store carbon in the topsoil:A case study at Sasso Fratino,Italy

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Journal of Forestry Research 2024年第2期35卷 23-32页

作者： Tommaso Chiti Nicola Benilli Giovanni Mastrolonardo Giacomo Certini Dipartimento per la Innovazione nei Sistemi Biologici Agroalimentari e Forestali(DIBAF)Universitàdella TusciaVia San C.de Lellis Snc01100 ViterboItaly Dipartimento di Scienze e Tecnologie Agrarie AlimentariAmbientali e Forestali(DAGRI)Universitàdegli Studi di FirenzeP.le delle Cascine 1850144 FirenzeItaly

There is considerable interest devoted to oldgrowth forests and their capacity to store carbon(C)in biomass and *** of C stocks in old-growth forests are carried out worldwide,although there is a lack of information on their actual potential for C *** further understand this,soil organic carbon(SOC)was measured in one of Italy's best-preserved old-growth forests,the Sasso Fratino Integral Nature *** reserve is on the World Heritage List along with other ancient beech forests of Europe,and it is virtually untouched due to the steepness of the terrain,even before legal constraints were *** the sandstone-derived soils are often shallow,they are rich in organic ***,no quantification had been carried *** systematically sampling the topsoil across the forest,we accurately determined the average amount of SOC(62.0±16.9 Mg ha^(–1))and nitrogen(4.0±1.2 Mg ha^(–1))in the top 20 *** the CENTURY model,future dynamics of SOC stocks were predicted to 2050 according to two climate scenarios,A1F1 and B2,the first of high concern and the second more *** model projected an increase of 0.2 and 0.3 Mg ha^(–1)a^(–1)by 2030 under the A1F1 and B2 scenarios,respectively,suggesting that the topsoil in old-growth forests does not reach equilibrium but continues accumulating ***,from 2030 to 2050,a decline in SOC accumulation is predicted,indicating SOC net loss at high altitudes under the worst-case *** study confirms that soils in oldgrowth forests play a significant role in carbon *** also suggests that climate change may affect the potential of these forests to store SOC not only in the long term but also in the coming years.

关键词： Carbon sequestration CENTURY model Climate change Forest soil Soil nitrogen

A partition-of-unity based three-node triangular element with continuous nodal stress using radial-polynomial basis functions

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Science China(Technological Sciences) 2017年第10期60卷 1518-1536页

作者： YANG YongTao ZHENG hong xu DongDong State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of Sciences Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of Technology Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources Yangtze River Scientific Research Institute

A partition-of-unity （PU） based ＂FE-Meshfree＂ three-node triangular element （Trig3-RPIM） was recently developed for linear elastic problems. This Trig3-RPIM element employs hybrid shape functions that combine the shape functions of three-node triangular element （Trig3） and radial-polynomial basis functions for the purpose of synergizing the merits of both finite element method and meshfree method. Although Trig3-RPIM element is capable of obtaining higher accuracy and convergence rate than the Trig3 element and four-node iso-parametric quadrilateral element without adding extra nodes or degrees of freedom （DOFs）, the nodal stress field through Trig3-RP1M element is not continuous and extra stress smooth operations are still needed in the post processing stage. To further improve the property of Trig3-RPIM element, a new PU-based triangular element with continuous nodal stress, called Trig3-RPIMcns, is developed. Numerical examples including several linear, free vibration and forced vibration test problems, have confirmed the correctness and feasibility of the proposed Trig3-RPIMcns element.

关键词： partition of unity FE-Meshfree element Trig3-RPlMcns mesh distortion radial-polynomial basis functions

A comprehensive review of meal?replacement from dining table to sickbed: beyond biomedical potentials

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Food Science and Human Wellness 2024年

作者： Hao Qiang Tianshu xu Peng Ma Siyuan Zhang Guanhua Du Guifen Qiang Tengfei Ji The School of Chemistry， Cardiff University State Key Laboratory of Bioactive Substance and Function of Natural Medicines， Institute of Materia Medica， Chinese Academy of Medical Sciences and Peking Union Medical College and Beijing Key Laboratory of Drug Target and Screening Research State Key Laboratory， Institute of Materia Medica， Chinese Academy of Medical Sciences and Peking Union Medical College

The emergence of meal replacement (MR) originates from physical exercise or fitness as a substitute for one or all meals and later expands to the field of weight loss. Indeed， the main application of current meal replacement is to lose body weight， whether patients with obesity， diabetes， fatty liver， infertile or pregnant women can benefit from weight loss. In addition， MRs still exhibit more biomedical potential in preventing and treating diseases， like anti-diabetes， improving fatty liver and kidney disease， preventing cancer， conceiving and reducing pregnancy complications， and improving life quality. Indeed， there are also disadvantages to meal replacement， including causing adverse effects， although most are acceptable and tolerated. To date， various commercially-developed MRs are walking from dining table to sickbed. Therefore， a scientific understanding of the advantages and disadvantages of meal replacements is crucial for their extensive application beyond biomedical potentials.

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鸟巢式护理联合蓝光治疗新生儿高胆红素血症中的应用效果

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临床研究 2024年第5期32卷 164-167页

作者：徐彩云李红漯河市骨科医院儿科河南漯河462300

目的探讨鸟巢式护理+蓝光治疗在新生儿高胆红素血症(NHB)中的应用价值并分析对患儿依从性与黄疸指数的影响。方法将2020年1月至2022年12月期间在漯河市骨科医院治疗的NHB患儿(78例)作为研究对象,依据区间随机法将其分为对照组、研究组... 详细信息

目的探讨鸟巢式护理+蓝光治疗在新生儿高胆红素血症(NHB)中的应用价值并分析对患儿依从性与黄疸指数的影响。方法将2020年1月至2022年12月期间在漯河市骨科医院治疗的NHB患儿(78例)作为研究对象,依据区间随机法将其分为对照组、研究组,各39例,两组均接受蓝光治疗,对照组治疗期间实施常规护理,研究组治疗期间实施鸟巢式护理。比较两组干预前后血清胆红素水平、黄疸指数水平、症状消失时间及患儿治疗依从度。结果护理前,两组血清胆红素、黄疸指数比较,差异无统计学意义(P> 0.05);护理后,两组血清胆红素、黄疸指数均有所下降,且研究组低于对照组,差异有统计学意义(P <0.05)。研究组皮肤颜色恢复正常时间、大便颜色恢复正常时间、黄疸完全消失时间、出暖箱时间均短于对照组,差异有统计学意义(P <0.05)。研究组蓝光治疗期间不良反应发生率(10.26%)低于对照组(30.77%),差异有统计学意义(P <0.05)。研究组患儿治疗依从率(89.74%)高于对照组(61.54%),差异有统计学意义(P <0.05)。结论利用鸟巢护理配合蓝光治疗可提升对NHB的治疗效果,在降低黄疸指数、血清胆红素、加速基本症状改善时间等方面均有体现,同时可明显提升NHB患儿治疗依从度,预防蓝光治疗期间潜在的不良反应。

关键词：鸟巢式护理蓝光治疗高胆红素血症黄疸指数依从性

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胆囊切除术后胆汁反流性胃炎中西医研究现状

中国中医药图书情报杂志 2024年第2期48卷 234-238页

作者：许帆朱磊沈洪南京中医药大学附属医院江苏南京210029 江苏省中医院江苏南京210029

胆汁反流性胃炎(BRG)的病因众多,可能与胃肠动力紊乱、幽门螺杆菌感染、胆系疾患、外科手术等有关。其中,胆囊切除与BRG的发生关系密切,目前认为,胆囊切除术后BRG发病机制与术后胆囊功能缺失、神经体液调节异常、幽门-十二指肠运动失调... 详细信息

胆汁反流性胃炎(BRG)的病因众多,可能与胃肠动力紊乱、幽门螺杆菌感染、胆系疾患、外科手术等有关。其中,胆囊切除与BRG的发生关系密切,目前认为,胆囊切除术后BRG发病机制与术后胆囊功能缺失、神经体液调节异常、幽门-十二指肠运动失调、胆汁酸代谢异常等有关。目前中西医结合治疗已成为趋势。本文对近年来胆囊切除术后BRG的中西医发病机制及治疗现状进行综述,以期为临床治疗胆囊切除术后BR G提供诊疗思路。

关键词：胆汁反流性胃炎胆囊切除术发病机制中西医治疗综述

Feasibility study on buoyancy-weight ratios of a submerged floating tunnel prototype subjected to hydrodynamic loads

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Acta Mechanica Sinica 2015年第5期31卷 750-761页

作者： xu Long Fei Ge Youshi hong School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical University State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of Sciences

The research progress of a novel traffic solution,a submerged floating tunnel（SFT）,is reviewed in terms of a study approach and loading *** existing publications,the buoyancy-weight ratio（BWR） is usually ***,BWR is a critical structural parameter that tremendously affects the dynamic behaviour of not only the tunnel tube itself but also the cable *** the context of a SFT prototype（SFTP） project in Qiandao Lake（Zhejiang Province,China）,the importance of BWR is illustrated by finite element analysis and subsequently,an optimized BWR is proposed within a reasonable range in the present *** the numerical model,structural damping is identified to be of *** damping and the corresponding Rayleigh coefficients are attained through a sensitivity study,which shows that the adopted damping ratios are fairly suitable for ***,the human sense of security is considered by quantifying the comfort index,which helps further optimize BWR in the SFTP structural parameter design.

关键词： Submerged floating tunnel Buoyancy-weight ratio Water wave and current loads Dynamic response Human security sense Comfort index

Hydrothermal Synthesis and Crystal Structure of Iron Molybdophosphate Fe[Mo_6O_(12)(OH)_3(H_2PO_4)(HPO_4)_2(PO_4)]_2- [Fe(2,2′-bipy)(H_2O)_2]_2[Fe(2,2′-bipy)_3]_2·6H_2O

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1117-1122页

作者： GUO hong-xu LIU Shi-Xiong Department of Chemistry Fuzhou University Fuzhou 350002 China Department of Chemistry Zhangzhou Teachers College Zhangzhou 363000 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

A molybdenum（V） phosphate supported by iron coordination complexes, Fe[Mo6O12（OH）3（H2PO4）（HPO4）2（PO4）]2[Fe（2,2′-bipy）（H2O）2]2[Fe（2,2′-bipy）3]2·6H2O （bipy = 2,2′-bipyridine） 1, has been synthesized by hydrothermal synthesis and characterized. The title complex crystallizes in the monoclinic system, space group P21/c with a = 14.0005（8）, b = 25.5229（12）, c = 17.9956（9） A, β = 103.470（2）°, V= 6253.5（6） A^3, Z= 2, Mr = 4114.03, Dc = 2.185 g/cm^3, F（000） = 4040, μ = 1.931 mm^-1, R = 0.0438 and wR = 0. 1168. The structure of the title polyoxometalate anion is based on a centrosymmetrical cluster Fe[Mo6O2（OH）3（H2PO4）（HPO4）2（PO4）]2 supported by two [Fe（2,2′-bipy）（H2O）2] subunits. The 2D network is formed through intermolecular hydrogen bonds.

关键词： molybdophosphate iron complex hydrothermal synthesis crystal structure

A novel fault tolerant permanent magnet synchronous motor with improved optimal torque control for aerospace application

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Chinese Journal of Aeronautics 2015年第2期28卷 535-544页

作者： Guo hong xu Jinquan Kuang Xiaolin School of Automation Science and Electrical Engineering Beihang University

Improving fault tolerant performance of permanent magnet synchronous motor has always been the central issue of the electrically supplied actuator for aerospace application. In this paper, a novel fault tolerant permanent magnet synchronous motor is proposed, which is character- ized by two stators and two rotors on the same shaft with a circumferential displacement of mechanical angle of 4.5°. It helps to reduce the cogging torque. Each segment of the stator and the rotor can be considered as an 8-pole/10-slot five-phase permanent magnet synchronous motor with concentrated, single-layer and alternate teeth wound winding, which enhance the fault isola- tion capacity of the motor. Furthermore, the motor has high phase inductance to restrain the short-circuit current. In addition, an improved optimal torque control strategy is proposed to make the motor work well under the open-circuit fault and short-circuit fault conditions. Simulation and experiment results show that the proposed fault tolerant motor system has excellent fault tolerant capacity, which is able to operate continuously under the third open-circuit fault and second short- circuit fault condition without system performance degradation, which was not available earlier.

关键词： Actuator Fault isolation Fault tolerant Optimal torque control Permanent magnet moto

Measurements of heat transfer and pressure in a trailing edge cavity of a turbine blade

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Chinese Journal of Aeronautics 2013年第2期26卷 294-308页

作者： Wu hong Liu Yusheng xu Guoqiang National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy and Power Engineering Beihang University

An experimental investigation is conducted to obtain the heat transfer and pressure drop data for an integral trailing edge cavity test section that simulates a novel turbine blade＇s internal cooling passage with bleed holes. Local heat transfer is measured on both the suction and pressure sides by a transient liquid crystal technique, while pressures at six positions are recorded by pressure calibrators. Moreover, flow characteristic and its effect on heat transfer are analyzed for conditions with or without bleed flow. The experimental results show that, in the cases with bleed flow, local heat transfer on the pressure side exceeds that on the suction side in the first and second channels. In the cases without bleed flow, in the first and third channels, local heat transfer on the suction side weakens whilst it increases significantly on the pressure side. For the second channel, non-bleed condition leads to a more balanced heat transfer distribution between the upstream and downstream channel. Besides, after the bleed holes are blocked, heat transfer in the first bend region on the suction side declines sharply, while the opposite phenomenon occurs for the second bend region on the pressure side. In both bleed and non-bleed cases, the total pressure of six measurement positions decreases continuously along the channel at the same Reynolds number and it promotes for higher Reynolds number. Among all the measurement points, under the same flow rate condition, the highest speed occurs at Position 5, which also shows the maximum difference between the total and static pressures. When the bleed holes are blocked, the total pressure at each measurement position appears to increase.

关键词： Bleed flow Cooling Gas turbines Heat transfer Liquid crystals Transient