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Applicability of Temperature Discrete Equation to NMRF Boundary Layer Scheme in GRAPES Model

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Journal of Tropical Meteorology 2022年第1期28卷 12-28页

作者： ZHANG Yan-xia chen Zi-tong MENG Wei-guang xu Dao-shen guangzhou Institute of Tropical and Marine Meteorology/guangdong Provincial Key Laboratory of Regional Numerical Weather Prediction CMAGuangzhou 510641 China

By deriving the discrete equation of the parameterized equation for the New Medium-Range Forecast(NMRF)boundary layer scheme in the GRAPES model,the adjusted discrete equation for temperature is obviously different from the original equation under the background of hydrostatic equilibrium and adiabatic *** the present research,three discrete equations for temperature in the NMRF boundary layer scheme are applied,namely the original(hereafter NMRF),the adjustment(hereafter NMRF-gocp),and the one in the YSU boundary-layer scheme(hereafter NMRF-TZ).The results show that the deviations of height,temperature,U and V wind in the boundary layer in the NMRF-gocp and NMRF-TZ experiments are smaller than those in the NMRF experiment and the deviations in the NMRF-gocp experiment are the *** deviations of humidity are complex for the different forecasting lead time in the three ***,there are obvious diurnal variations of deviations from these variables,where the diurnal variations of deviations from height and temperature are similar and those from U and V wind are also ***,the diurnal variation of humidity is relatively *** root means square errors of 2m temperature(T2m)and 10m speed(V10m)from the three experiments show that the error of NMRF-gocp is the smallest and that of NMRF is the *** is also a diurnal variation of T2m and V10m,where T2m has double peaks and V10m has only one *** of the discrete equations between NMRF and NMRF-gocp experiments shows that the deviation of temperature is likely to be caused by the calculation of vertical eddy diffusive coefficients of heating,which also leads to the deviations of other elements.

关键词： NMRF boundary layer scheme turbulent equation temperature discrete equation CMA-GD model

The effect of low-molecular-weight organic-acids(LMWOAs)on treatment of chromium-contaminated soils by compost-phytoremediation: Kinetics of the chromium release and fractionation

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Journal of Environmental Sciences 2018年第8期30卷 45-53页

作者： Huixia chen Junfeng Dou Hongbin xu College of Water Sciences Beijing Normal University Key Laboratory of Green Process and Engineering Chinese Academy of Sciences National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Institute of Process EngineeringChinese Academy of Sciences

A soil–plant biological system was developed from chromium（Cr） polluted soil treated by the compost-phytoremediation method. The transformation and migration of the Cr in this system is comprehensively studied in this research. The results illustrated that the co-composting treatment can reduce the Cr availability from 39%（F1 was about 31% of total, F2 was about 8% of total） to less than 2% by stabilizing the Cr. However, herbaceous plants can accumulate the concentrations of Cr from 113.8 to 265.2 mg/kg in the two crops,even though the concentration of soluble Cr in the substrate soil was below 0.1 mg/*** can be assimilated and easily transferred in the tissues of plants because the lowmolecular-weight organic-acids（LMWOAs） derived from the plant root increase the bioavailability of Cr. The amount of extracted Cr dramatically increased when the organic acids were substituted in this order： citric acid 〉 malic acid 〉 tartaric acid 〉 oxalic acid 〉acetic acid. On average the maximum（147.4 mg/kg） and the minimum（78.75 mg/kg） Cr were extracted by 20 mmol/L citric acid and acetic acid, respectively. The desorption of Cr in different acid solutions can be predicted by the pseudo second-order kinetics. The exchangeable Cr, carbonate-bound Cr, and residual Cr decreased, while Fe–Mn oxide bound Cr and organic bound Cr increased in the soil solid phase. According to the experimental results, the organic acids will promote the desorption and chelation processes of Cr, leading to the remobilization of Cr in the soil.

关键词： Chromium Phytoextraction Desorption Release kinetics Speciation

Dynamic modeling and simulation of a pressurized system used in flight vehicle

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Chinese Journal of Aeronautics 2018年第6期31卷 1232-1248页

作者： Bing SUN Qi xu Yang chen School of Astronautics Beihang University

For a typical pressurized system with a novel dual-stage gas pressure reducing regulator,a system model is established with modular models of various typical components. The simulation study on the whole working period shows that the general trends and magnitudes of simulation curves are in agreement with experimental measured curves. As the key component in the pressurized system, the regulator is studied by a series of numerical simulations to reveal the influences of various structure parameters on its stability. Furthermore, the variable ranges which can guarantee the stability of regulator and system are obtained to provide guidance for design. The modeling and analysis approach can be applied to other systems and components.

关键词： Dual-stage gas pressure reducing regulator Dynamic characteristics Finite volume method Numerical simulation Pressurized system Stability

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顺层变质岩坡稳定性评价与生态治理方案

科学技术与工程 2024年第6期24卷 2284-2292页

作者：祝威陈旭勇康钦容董杰华武汉工程大学土木与建筑工程学院武汉430073 武汉工程大学资源与安全工程学院武汉430073

为了探究鄂西北变质岩区不稳定斜坡滑崩地质灾害的成因机制和生态治理模式,以三用塘顺层变质岩不稳定斜坡为研究对象,在查明灾害体地质与变形特征的基础上,分析了其可能的破坏模式与主要影响因素,深入探究了顺层变质岩坡渐进式变形破坏... 详细信息

为了探究鄂西北变质岩区不稳定斜坡滑崩地质灾害的成因机制和生态治理模式,以三用塘顺层变质岩不稳定斜坡为研究对象,在查明灾害体地质与变形特征的基础上,分析了其可能的破坏模式与主要影响因素,深入探究了顺层变质岩坡渐进式变形破坏的成因机理。采用极限平衡等方法对不稳定斜坡进行了稳定性分析评价,结果表明,该斜坡体处于不稳定状态。基于地质灾害生态治理理念,提出了削方整形、护脚墙、格构锚固、截排水沟、生态绿化与监测等综合防治措施。通过工程实施及效果监测表明:该治理方案不仅有效地消除了三用塘滑崩地质灾害安全问题,而且取得了良好的环境绿化与美化效果。其综合防治措施,特别是将地质灾害防治与生态绿化融为一体的生态治理模式可为同类顺层变质岩不稳定斜坡的加固与坡面防护提供借鉴。

关键词：顺层变质岩破坏机理稳定性评价防治措施生态治理

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物联网在林业行业中的应用分析

林业科技情报 2024年第1期56卷 11-14页

作者：陈志敬李涛黎明陈广刘健斌广东省林业事务中心广州510173

本文基于物联网的由来及概念,结合林业行业的特点着手展开研究分析,对林业物联网的结构模型进行分解及组成研究,研究和分析了林业物联网相关的技术和标准。文中阐述了目前应用中的若干传感器,以及相关的业务应用系统,并对比了国内外的... 详细信息

本文基于物联网的由来及概念,结合林业行业的特点着手展开研究分析,对林业物联网的结构模型进行分解及组成研究,研究和分析了林业物联网相关的技术和标准。文中阐述了目前应用中的若干传感器,以及相关的业务应用系统,并对比了国内外的有关应用。提出了关注传感器等国产化的应用,以及优化调整林业物联网数据存储入库使用的一体化数据库。

关键词：林业物联网传感器物联网应用一体化数据库

依达拉奉右莰醇联合瑞舒伐他汀钙治疗急性后循环脑梗死患者的临床研究

同方期刊数据库博看期刊评论

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中国临床药理学杂志 2024年第7期40卷 949-953页

作者：许彤史菡萏邵淋淋陈良富东阳市中医院神经内科浙江东阳322100

目的观察依达拉奉右莰醇注射用浓溶液联合瑞舒伐他汀钙胶囊治疗急性后循环脑梗死患者的临床疗效及安全性。方法将急性后循环脑梗死患者按队列法分为对照组和试验组。对照组给予瑞舒伐他汀钙5 mg;试验组在对照组治疗的基础上,静脉滴注... 详细信息

目的观察依达拉奉右莰醇注射用浓溶液联合瑞舒伐他汀钙胶囊治疗急性后循环脑梗死患者的临床疗效及安全性。方法将急性后循环脑梗死患者按队列法分为对照组和试验组。对照组给予瑞舒伐他汀钙5 mg;试验组在对照组治疗的基础上,静脉滴注依达拉奉右莰醇注射用浓溶液15 mL。比较2组患者的临床疗效,神经功能、生化指标、氧化应激反应指标、Toll样受体4/核因子κB(TLR4/NF-κB)信号通路分子水平,预后和药物不良反应发生情况。结果对照组入组49例,试验组入组51例。治疗后,试验组和对照组的总有效率分别为92.16%(47例/51例)和77.55%(38例/49例),在统计学上差异有统计学意义(P0.05)。结论依达拉奉右莰醇注射用浓溶液联合瑞舒伐他汀钙胶囊治疗急性后循环脑梗死患者的临床疗效明确,其能有效调节患者神经功能、氧化应激反应和血脂及TLR4/NF-κB信号通路分子水平,明显改善患者预后。

关键词：依达拉奉右莰醇注射用浓溶液瑞舒伐他汀钙胶囊急性后循环脑梗死神经功能 Toll样受体4/核因子КB

低碳含铌建筑结构用钢动态CCT曲线及冷却工艺研究

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武汉科技大学学报 2024年第5期47卷 329-338页

作者：邹佳辉田俊羽李显肖娟肖雅倩饶龙浩徐光武汉科技大学省部共建耐火材料与冶金国家重点实验室湖北武汉430081 广西柳州钢铁集团有限公司技术中心广西柳州545002

采用Gleeble-3500热模拟实验机,对低碳含铌建筑结构用钢进行了动态过冷奥氏体连续冷却转变(CCT)实验研究,结合不同冷却速度下实验钢的膨胀曲线、显微组织和显微维氏硬度,绘制了实验钢动态CCT曲线。结果表明,随着冷却速度的提高,连续冷... 详细信息

采用Gleeble-3500热模拟实验机,对低碳含铌建筑结构用钢进行了动态过冷奥氏体连续冷却转变(CCT)实验研究,结合不同冷却速度下实验钢的膨胀曲线、显微组织和显微维氏硬度,绘制了实验钢动态CCT曲线。结果表明,随着冷却速度的提高,连续冷却相变温度区间向低温方向移动,促进铁素体晶粒形核,有效细化铁素体晶粒尺寸。此外,结合动态CCT曲线,设置了不同冷却工艺参数,确定冷却速度和空冷开始温度对实验钢相变和组织的影响。结果表明,为空冷开始温度设定为550、600℃时,室温组织主要为铁素体和粒状贝氏体。同一空冷温度下,随着冷速的增加,铁素体含量减少,贝氏体含量增加;而在相同冷速下,降低空冷温度会导致铁素体含量增加。当空冷开始温度设定为650℃时,无论冷速是5℃/s还是10℃/s,室温组织主要为铁素体和珠光体,且随着冷速的提升,铁素体含量因相变时间的缩短而降低。

关键词：低碳含铌钢 CCT曲线冷却工艺相变微观组织

Recent progress in cationic polymeric gene carriers for cancer therapy

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Science China Chemistry 2017年第3期60卷 319-328页

作者： Caina xu Huayu Tian xuesi chen Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

In recent years,various carriers for gene delivery nave been developed for biomedical *** all kinds of gene carriers,cationic polymeric carriers for delivery therapeutic gene as non-viral carriers have received growing interests due to their improved high transfection efficiency with the relative *** particular,the advancement of novel polymeric gene carriers has gained much progress in the development of effective anticancer ***,this review focused on the development of cationic polymeric carriers for cancer therapy,including polyethylenimine(PEI),polyamidoamine(PAMAM) dendrimers,polylysine(PLL),chitosan and modified cationic *** recent progresses in the development of novel polymeric carriers for gene delivery,such as targeted gene carriers,responsive gene carriers and multifunctional gene carriers,were ***,the future perspectives in the development of novel polymeric carriers for delivery gene were presented.

关键词： polymeric gene carriers cancer therapy stimuli-responsive carriers multifunctional gene carriers

A new method to predict mechanical properties for microalloyed steels via industrial data and mechanism analysis

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Journal of Iron and Steel Research International 2019年第3期26卷 230-241页

作者： Wei-gang Li Wei Yang Yun-tao Zhao guang xu Xiang-hua Liu Engineering Research Center for Metallurgical Automation and Measurement Technology of Ministry of Education Wuhan University of Science and Technology Wuhan 430081Hubei China The State Key Laboratory of Refractories and Metallurgy Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of EducationWuhan University of Science and TechnologyWuhan 430081 HubeiChina Research Institute of Science and Technology Northeastern University Shenyang 110819 LiaoningChina

A new modeling method has been developed by combining industrial data and metallurgical *** method utilizes a series of models to predict the mechanical properties for microalloyed steels with high reliability and strong ***,the modeling process includes determining the influencing factors,cleaning the actual data,building sub-models for each single factor and for the interactions between the factors,verifying the reproducibility of the sub-models,and building the whole *** effects of alloying elements(such as C,Si,Nb,and V),precipitation processes of microalloying elements,and processing parameters(such as reheating temperature and coiling temperature)are quantitatively involved in the *** addition,the obtained models can quantitatively describe the effect of each factor on the mechanical properties,which is impossible by using traditional modeling methods.A practical modeling case is introduced,and the influencing mechanisms of the factors on the mechanical properties are *** results show that the prediction errors for the tensile strength and yield strength are 2.54%and 3.34%,respectively,which exhibits the advantages of high precision and strong adaptability of the model used to design and develop new steel grades,reduce the number of physical tests,and reduce the development cost of new products.

关键词： Additive model Mechanical property prediction Metallurgical mechanism Industrial data