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土地生态安全评价研究进展

安徽农业科学 2017年第22期45卷 148-150页

作者：詹文静杨国清白泽惠广东工业大学管理学院广东广州510520

通过对国内外土地生态安全评价研究的全面梳理,从土地生态安全的概念、评价指标、评价方法等方面,系统地阐述了近几年来土地生态安全评价的研究进展,由此指出土地生态安全评价研究存在的问题。

关键词：土地生态安全评价指标体系评价方法

老年局限期食管小细胞癌临床病理特征及预后分析

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中华肿瘤防治杂志 2016年第18期23卷 1254-1259页

作者：王玉栋焦文鹏王军王祎曹峰武亚晶郭银刘青程云杰河北医科大学第四医院肿瘤内科河北石家庄050011 河北医科大学第四医院放疗科河北石家庄050011

目的老年食管癌发病率近年来呈上升的趋势,但关于其临床病理特征及预后因素的研究,尤其是老年食管小细胞癌(primary esophageal small cell of carcinomas,PESC)的研究极为少见。本研究通过探讨老年原发性局限期PESC的临床病理特征及预... 详细信息

目的老年食管癌发病率近年来呈上升的趋势,但关于其临床病理特征及预后因素的研究,尤其是老年食管小细胞癌(primary esophageal small cell of carcinomas,PESC)的研究极为少见。本研究通过探讨老年原发性局限期PESC的临床病理特征及预后影响因素,以期为临床提供参考。方法回顾性分析河北医科大学第四医院2004-01-01-2012-12-31收治的34例经手术切除的原发性老年局限期PESC患者的临床资料,其中单纯手术组19例,术后辅助治疗组15例(手术+化疗9例,手术+放化疗6例)。分析其临床病理特征和淋巴结转移情况,Kaplan-Meier法统计不同治疗方式的局控、远转和生存情况,Cox回归进行多因素分析。结果 17例患者发生淋巴结转移,淋巴结转移率为50.0%(17/34)。41枚发生淋巴结转移,淋巴结转移度为13.1%(41/314)。胸上段PESC上纵隔、中纵隔、下纵隔和腹腔淋巴结转移度分别为28.6%、0、0和0;胸中段PESC分别为16.7%、10.9%、9.4%和16.4%;胸下段PESC分别为0、0、17.4%和24.1%。T3-4期患者淋巴结转移度显著高于T1-2期(20.6%vs 4.5%,χ2=8.050,P=0.005);病变长度≥5cm组淋巴结转移度显著高于<5cm组(17.0%vs 8.0%,χ2=5.611,P=0.018);多因素分析未发现影响淋巴结转移的独立危险因素。单纯手术组患者1、3、5年局控率与生存率分别为82.1%、54.7%、54.7%和42.1%、15.8%、5.3%,术后辅助治疗组分别为86.2%、65.6%、65.6%和93.3%,46.7%,31.1%,两组比较局控率差异无统计学意义(χ2=0.001,P=0.972),术后辅助治疗组生存率优于单纯手术组,χ2=4.105,P=0.043。单纯手术组患者1、3、5年远转率分别为54.3%、71.4%和85.7%,显著高于术后辅助治疗组的13.3%、30.0%和30.0%,χ2=6.632,P=0.010。多因素分析显示,化疗与否是老年局限期PESC生存的独立影响因素,P=0.017。结论老年PESC淋巴结转移程度与转移模式并未随年龄的增长而发生明显变化,淋巴结转移模式与食管鳞癌较为相似,但远处转移率显著高于食管鳞癌。单纯手术治疗预后极差,术后辅助放化疗可延长其生存。系统性化疗在老年患者体质能耐受的情况下仍是治疗基石之选择。

关键词：食管肿瘤小细胞癌肿瘤转移淋巴结治疗模式预后

基于模糊综合评判的炮兵部(分)队机动训练评估

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兵器装备工程学报 2017年第3期38卷 89-92页

作者：陈春李伟龙陶晶黎国庆陆军军官学院二系 69240部队

着眼炮兵部(分)队机动训练的特点,从信息获取、指挥控制、战术机动、整体防护和综合保障等方面构建炮兵机动训练的评估指标体系,采用层次分析法和模糊综合评判的方法对炮兵部(分)队机动训练进行了综合评估。

关键词：炮兵部(分)队机动训练评估模糊综合评判

Gasification kinetics of char formed from waste polyvinyl chloride for efficient utilization in ironmaking process

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Journal of Iron and Steel Research International 2022年第10期29卷 1535-1544页

作者： Guang Wang Hong-qiang Zhang jing-song Wang qing-guo Xue State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China

In the prevailing incineration processes of municipal solid waste,the presence of polyvinyl chloride(PVC)may cause environmental *** energy-intensive ironmaking sector in the iron and steel industry operates at high temperature and under high reduction potential with the function of energy conversion,which can provide a potential path for the collaborative utilization of waste plastics in large quantities and low *** gasification of the char formed from PVC when processed in the ironmaking sector is significant for the development of the related ***,the gasification experiment of PVC char and traditional carbonaceous materials was performed by thermogravimetric *** results indicated that the gasification ability decreased in the sequence of PVC char>anthracite coal>coke>***,kinetics were also analyzed by Coats-Redfern and Doyle *** PVC char showed the best gasification ability with the smallest activation energy,ranging from 87.18 to 117.52 kJ/mol,and the smaller graphitization degree of PVC char compared with other carbonaceous materials should be the main reason for its excellent gasification reactivity.

关键词： Polyvinyl chloride(PVC) Thermochemical conversion Ironmaking Char Gasification

Effect of slag composition on kinetic behavior of deep deoxidation of 5 wt.% Si high-silicon austenitic stainless steel

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Journal of Iron and Steel Research International 2024年第8期31卷 1873-1885页

作者： Guan-xiong Dou Han-jie guo jing guo Xue-cheng Peng qing-yun Chen School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing 100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing 100083China

Based on a thermodynamic study of 5 wt.%Si high-silicon austenitic stainless steel(SS-5Si)smelting using CaF_(2)-CaO-Al_(2)0_(3)-Mg-Si0_(2) slag to obtain a low oxygen content of less than 10×10^(-4) wt.%,a kinetic mass transfer model for deep deoxidation was established through laboratory studies,and the effects of slag components and temperature on deoxidation during the slag-steel reaction process of sS-5Si were systematically *** experimental data verified the accuracy of the model *** results showed that the final oxygen content in the steel at 1873 K was mainly controlled by the oxygen content derived from the activity of SiO_(2) regulated by the[Si]-[O]equilibrium reaction in the slag system;in particular,when the slag basicity R(R=w(CaO)/w(SiO2),where w(CaO)and w(SiO_(2))are the contents of CaO and SiO_(2) in the slag,respectively)is 3,the Al2O3 content in the slag needs to be less than 2.7%.The mass transfer rate equation for the kinetics of the deoxidation reaction revealed that the mass transfer of oxygen in the liquid metal is the rate-controlling step under different slag conditions at 1873 K,and the oxygen transfer coefficient ko.m increases with increasing the slag basicity from 4.0×10^(-6)m s^(-1)(R=1)to 4.3×10^(-5) m s^(-1)(R=3).ko.m values at R=2 and R=3 are almost the same,indicating that high slag basicity has little *** integral of the mass transfer rate equation for the deoxidation reaction of SS-5Si under different slag conditions is *** total oxygen content of the molten steel decreases with increasing basicity from an initial content of 22×10^(-4) to 3.2×10^(-4) wt.%(R=3),consistent with the change in ko.m with slag *** R=2,the slag-steel reaction takes 15 min to reach equilibrium(w[O]=5.5×10^(-4) wt.%),whereas at R=3,the slag-steel reaction takes 30 min to reach equilibrium(w[0]=3.2×10^(-4) wt.%).Considering the depth of deoxidation and reaction time of SS-5Si smelting,it is recommended the slag b

关键词： Slag-steel reaction Kinetics Rate-controlling step Deep deoxidation Transfer coefficient

DETACHED EDDY SIMULATION OF HYDRAULIC CHARACTERISTICS ALONG THE SIDE-WALL AFTER A NEW ARRANGEMENT-SCHEME OF THE SUDDEN LATERAL ENLARGEMENT AND THE VERTICAL DROP

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Journal of Hydrodynamics 2011年第5期23卷 669-675页

作者： LI guo-jing DAI Guang-qing YANG qing MA Xu-dong State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China

In order to study the cavitation damage in a side-wall when a sudden lateral enlargement and a vertical drop are imposed at the radial gate, a new arrangement-scheme is proposed, where the sudden lateral enlargement and the vertical drop can be imposed at the outlet of the gate chamber. The hydraulic characteristics along the side-wall are simulated by the detached eddy simulation and the Volume Of Fluid （VOF） method. The numerical results agree well with those of experiment. The experimental and numerical results show that the flow condition is smooth with only a weak water-wing appearing behind the lateral cavity, and the length of the lateral cavity becomes longer and is mainly affected by the size of the lateral enlargement and the zone of negative pressure after the water impacts the side-wall would disappear. The hydraulic characteristics of the new arrangement-scheme are beneficial to the prevention of the cavitation damage in the side-wall and the Detached Eddy Simulation （DES） with the VOF method can well predict the hydraulic characteristics after the new arrangement-scheme of the sudden lateral enlargement and the vertical drop.

关键词： model test aeration to prevent cavitation damage realizable k - ε turbulent model Detached Eddy Simulation (DES) Volume Of Fluid (VOF) method

Mathematical model of burden distribution in bell-less top blast furnace

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Journal of Iron and Steel Research International 2023年第2期30卷 216-226页

作者： Jian-sheng Chen Hai-bin Zuo jing-xiu Wang qing-guo Xue jing-song Wang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China

The burden distribution in the shaft of blast furnace is known to affect the gas distribution,heat transfer,and chemical reactions inside the ***,the internal layer structure of burden in the shaft cannot be directly ***,a mathematical model for evaluating burden profile and layer structure was established.A sensitivity analysis based on the model was implemented to elucidate the effect of some factors on the burden distribution,including the stockline height and the mass of central *** results show that the width of funnel zone widens with the increase in stockline height,and the mass percentage of ore to coke in this zone slightly ***,the mass of central coke shows a significant influence on the width of coke channel,and 2%of batch mass of coke is recommended to implement central coke charging *** model has been indirectly verified by the gas temperature in operating blast furnace and successfully applied to online evaluate burden distribution.

关键词： Blast furnace Burden distribution Mathematical model Stockline height Central coke

Introducing a drought index to a crop model can help to reduce the gap between the simulated and statistical yield

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Atmospheric and Oceanic Science Letters 2018年第4期11卷 307-313页

作者： WANG guo-Cheng ZHANG qing XU jing-jing LAPC Institute of Atmospheric Physics Chinese Academy of Sciences

A well-established and pre-calibrated crop model can normally represent the overall characteristics of crop growth and ***,it can hardly include all relevant factors that affect the yield,and usually overestimates the crop yield when extreme weather conditions *** this study,the authors first introduced a drought index(the Standardized Precipitation Evapotranspiration Index)into a process-based crop model(the Agro-C model).Then,the authors evaluated the model’s performance in simulating the historical crop yields in a double cropping system in the Huang-Huai-Hai Plain of China,by comparing the model simulations to the statistical *** results showed that the adjusted Agro-C model significantly improved its performance in simulating the yields of both maize and wheat as affected by drought events,compared with its original *** can be concluded that incorporating a drought index into a crop model is feasible and can facilitate closing the gap between simulated and statistical yields.

关键词： Agro-C model crop yield drought index

Exploring a new path of green and efficient utilization of sinter return fine to produce composite pellets

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Journal of Iron and Steel Research International 2024年第7期31卷 1610-1622页

作者： Yan-biao Chen Wen-guo Liu Hao guo jing-song Wang qing-guo Xue Hai-bin Zuo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China MCC Capital Engineering and Research Incorporation Limited Beijing 100176China

Efficient utilization of sinter return fine is an important measure to reduce cost,increase efficiency,save energy and reduce emission.A new path of green and efficient utilization of return fine was proposed to produce composite *** metallurgical properties of composite pellets under the condition of hydrogen-rich blast furnace were *** experimental results indicate that the coated concentrate was consolidated for the composite pellets through normal Fe_(2)O_(3) *** the surface of core return fine,the liquid phase formed due to its low-melting point,assimilated the adjacent concentrate,and then consolidated with the temperature *** with regular pellets,the com-pressive strength and reduction swelling index of composite pellets were decreased,but the reducibility index and softening-melting properties were *** addition,the reduction degradation index of composite pellets was sig-nificantly higher than that of ***,adding composite pellets was conducive to indirect reduction in blast furnace,reducing fuel ratio and improving production *** to the effect of the roasting system on the metallurgical properties,the roasting temperature and time were determined as 1250℃and 30 min,*** composite pellets can be produced under the traditional pelletizing process.

关键词： Sinter Return fine Composite pellet Roasting system Metallurgical property Hydrogen-rich blast furnace