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模拟增温对大青山油松林凋落物分解动态的影响

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兰州大学学报（自然科学版） 2024年第5期60卷 599-604页

作者：李昕桥吴昊梁蕾马秀枝李长生韩晓荣内蒙古农业大学林学院呼和浩特010018 内蒙古自治区生态与农业气象中心呼和浩特010051 内蒙古自治区气象局呼和浩特010051 呼和浩特市气象局呼和浩特010000

探究模拟气候变暖对大青山油松人工林凋落物分解的影响.采用开顶式增温室法和原位模拟分解袋法,设置对照和增温两个处理.结果显示经过生长季分解后,增温处理凋落物质量残留率平均损失了初始质量的21.1%,对照组平均损失了初始质量的13.7%... 详细信息

探究模拟气候变暖对大青山油松人工林凋落物分解的影响.采用开顶式增温室法和原位模拟分解袋法,设置对照和增温两个处理.结果显示经过生长季分解后,增温处理凋落物质量残留率平均损失了初始质量的21.1%,对照组平均损失了初始质量的13.7%;增温显著降低了凋落物氮残留率(以全氮计),显著增加了凋落物磷残留率(以全磷计),增温和对照处理凋落物氮残留率分别为80.05%和94.37%;磷残留率分别为104.33%和96.42%;与对照相比,增温处理下凋落物的c(C)/c(N)、c(C)/c(P)、c(木质素)/c(N)均存在显著差异;增温处理显著增加了林内凋落物的分解系数,增温和对照处理凋落物分解系数分别为0.019和0.011.增温在一定程度上加速了油松林凋落物的分解.

关键词：模拟增温开顶式增温室法大青山油松人工林凋落物分解

New Method for Evaluating Thermal Wear of Rolls in Rolling Process

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Journal of Iron and Steel Research International 2008年第6期15卷 52-55页

作者： li chang-sheng liU Xiang-hua WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

A new method was developed by a thermal wear machine to evaluate the thermal wear of roils in steel rolling process. The steel strip and rolls were simulated by upper and lower heating disks. The upper heating disk could he kept at a temperature of over 900 ℃ by induction heating. The pressure between the disks as high as 323.2 MPa could be achieved and the slipping rate could be 12. 7 %. The thermal wear of high speed steel （HSS） roll material, the wear rate of the HSS roll, and the SEM morphology of a worn HSS roll surface were investigated. This method was useful and could be employed to simulate friction and wear between strip and roll during the strip rolling process.

关键词： thermal wear roll friction strip rolling induction heating

Experimental study on the effect of Kang-Lai-Te induced apoptosis of human hepatoma carcinoma cell HepG2

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Hepatobiliary & Pancreatic Diseases International 2009年第3期8卷 267-272页

作者： Lu, Yun Wu, li-Qun Dong, Qian li, chang-sheng Qingdao Univ Dept Hepatobiliary Surg Affiliated Hosp Coll Med Qingdao 266003 Peoples R China Qingdao Univ Dept Pediat Surg Affiliated Hosp Coll Med Qingdao 266003 Peoples R China Qingdao Univ Ctr Cell & Mol Pathol Affiliated Hosp Coll Med Qingdao 266003 Peoples R China

BACKGROUND: Kang-Lai-Te (KLT) is extracted from the traditional Chinese herbal medicine Semen Coicis, which has been used in China as an effective clinical drug for over a thousand years. It contains numerous ingredients with anti-tumor effects. In our previous studies on transplanted hepatomas in rats, KLT could stop the cells in the G2+M stage of cell cycle and then reduce the number of cells entering the stage G0 and G1, but the mechanism of the anti-proliferative effect was unknown. In this experiment, we examined whether KLT inhibits HepG2 cell growth, if so, tried to explore its mechanism. METHODS: KLT at different concentrations was used for the treatment of hepatocellular carcinoma cells in vitro, respectively. The proliferation inhibitory rate was evaluated by MTT assay, induction of cell apoptosis rate and the protein levels of Fas and Fas ligand (FasL) were determined by flow cytometry (FCM), and the expression of Fas and FasL mRNA was detected by real-time fluorescent quantitative RT-PCR. RESULTS: KLT produced an obvious time and dose-dependent inhibitory effect on HepG2 cells, and marked apoptosis was detected by FCM The protein of Fas increased by 11.01%, 18.71%, 28.71% and 37.15%; the protein of FasL increased by 1.49%, 1.91%, 3.27% and 3.38% in comparison with the control (Pliary Pancreat Dis Int 2009; 8: 267-272)

关键词： Kang-Lai-Te drugs, Chinese herbal hepatocellular carcinoma HepG2 Fas/FasL

Texture of Hot Rolled Strip for Fe-3Si Steel Produced by Thin Slab Casting and Rolling

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Journal of Iron and Steel Research International 2010年第12期17卷 46-53页

作者： li chang-sheng YANG Hua WANG Yan-fang YU Yong-mei State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China Shougang Qian'an Iron and Steel Corporation Qian'an 064404 Hebei China

Fe-3Si steel strip was produced by thin slab casting and rolling （TSCR） process in the laboratory. The microstructure and texture of hot rolled strip by different total reduction and rolling schedules were observed through EBSD technique and X-ray diffraction method. The rule of texture density for the a,ε and γ fibers was analyzed. When the total reduction was increased from 82.9% to 97.1%, the gradient of microstrueture and texture for A steel surface layer and center layer was found, {001}〈110〉 texture had higher intensity, and {001}〈110〉texture was changed to { 110 } 〈 001 〉 and { 112 } 〈 111 〉. The texture distribution with different reduction schedules for B steel was basically similar, but the Goss texture orientation density and volume fraction for B steel were higher, the hot rolling reduction schedule of C1 was effective for the formation of Goss texture. The research work was useful theoretical basis and reference data to develop electrical steel by thin slab continuous casting and direct rolling technology.

关键词： silicon steel texture hot rolling thin slab continuous casting direct rolling

Texture of Cold Rolled Strip of Fe-3Si Steel Produced by Thin Slab Casting and Rolling

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Journal of Iron and Steel Research International 2011年第3期18卷 40-46页

作者： li chang-sheng YANG Hua WANG Yan-fang YU Yong-mei State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110004LiaoningChina Shougang Qian'an Iron and Steel Corporation Qian'an 064404HebeiChina

The hot rolled strip of Fe-3Si steel was experimentally produced by thin slab casting and rolling（TSCR） process in the *** texture evolution rule was investigated during hot rolling and cold *** texture distribution of cold rolled strips with four kinds of cold rolling reduction schedules was observed through X-ray diffraction method,and the orientation density variation of 1/16 layer,1/8 layer,1/4 layer,and 1/2 layer in thickness was *** cold rolled texture of steel A with four kinds of cold rolling reduction schedules was mainly composed of α and γ *** rolling reduction ratio of 70% was more beneficial for obtaining more γ *** γ fiber texture orientation density of {111}01-1 and {111}1-1-2 was the largest on the 1/8 layer and 1/4 layer and the least on the 1/16 layer and 1/2 layer for steel *** texture orientation density of {001}-{223}11-0 in the α fibers for steel C was increased,but the texture orientation density of {332}-{110}11-0 was low.

关键词： silicon steel texture hot rolling cold rolling thin slab continuous casting direct rolling

Analysis of Strip Temperature in Hot Rolling Process by Finite Element Method

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Journal of Iron and Steel Research International 2010年第2期17卷 17-21页

作者： MEI Rui-bin li chang-sheng liU Xiang hua HAN Bin State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China Technical Center Wuhan Iron and Steel Group Co Wuhan 430080 Hubei China

The program was developed by finite element method to calculate the temperature distribution in hot strip rolling process. The heat transfer coefficients of air cooling, water cooling and thermal resistance between work roll and strip were analyzed, A new heat generation rate model was proposed according to the influence of source current density, work frequency, air gap and distance to edge on induction heating by finite element method （FEM）. The heat generation rate was considered in the thermal analysis to predict the temperature distribution in the induction heating. The influence of induction heating on the strip temperature was investigated for different slab thicknesses. The temperature difference became more and more obvious with the increase of thickness. The strip could be heated quickly by the induction heating both in surface and center because of the thermal conductivity and skin effect. The heat loss of radiation has important influence on the surface temperature. The surface temperature could be heated quickly by high frequency when the strip is thicker.

关键词： temperature distribution finite element method induction heating skin depth hot rolling

Behavior of Transversal Crack on Slab Corner During V-H Rolling Process

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Journal of Iron and Steel Research International 2006年第6期13卷 31-37页

作者： YU Hai-liang liU Xiang-hua li chang-sheng Y. Kusaba State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China Sumitomo Metal Industries Ltd Fuso-cho 660 AMAGASAKI Japan

The behavior of transversal cracks on the surface of the slab corner during vertical and horizontal （V-H） rolling process with flat vertical roll and groove vertical roll was simulated by explicit dynamic finite element method. The closure and growth of crack and the contact pressure on surfaces of the crack in contacting zone between slab and roll during rolling process were analyzed. The results showed that during vertical rolling process, when the groove vertical roll is used, the maximum contact pressure on surfaces of the crack is 115 MPa, and the closure of crack is stable when the flat vertical roll is used, the maximum contact pressure on surfaces of the crack is 70 MPa, and it fluctuates greatly. During horizontal rolling process, when groove vertical roll is used, the contact pressure becomes zero which may accelerate the growth of crack when flat vertical roll is used, there is still contact pressure. The cal culated results are in good agreement with the results of test.

关键词： slab crack V-H rolling process FEM

Modeling Soil Organic Carbon Storage and Its Dynamics in Croplands of China

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Agricultural Sciences in China 2010年第5期9卷 704-712页

作者： TANG Hua-jun QIU Jian-jun WANG li-gang li Hu li chang-sheng Eric van Ranst Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China Institute for the Study of Earth Oceans and Space University of New Hampshire Durham NH 03824 USA Department of Geology and Soil Science (WE13)/Laboratory of Soil Science Ghent University Gent B-9000 Belgium

Soil organic carbon （SOC） is one of the centre issues related to not only soil fertility but also environmental safety. Assessing SOC dynamics in croplands has been a challenge in China for long due to the lack of appropriate methodologies and data sources. As an alternative approach for studying SOC dynamics, process-based models are adopted to meet the needs. In this paper, a process-based model, DeNitrification-DeComposition （DNDC）, was applied to quantify the SOC storage and the spatial distribution in croplands of China in 2003, with the support of a newly compiled county-level soil/ climate/land use database. The simulated results showed that the total SOC storage in the top layer （0-30 cm） of the 1.18 × 10^8 ha croplands of China is 4.7-5.2 Pg C in 2003 with an average value of 4.95 Pg C. The SOC storage in the northeastern provinces （1.3 Pg C） accounts for about 1/4 of the whole national totals due to their dominantly fertile soils with high organic matter content. SOC density ranges from 3.9 to 4.4 kg C m 2, with an average of 4.2 kg C m^-2, a level is much lower than the world average level. The model results also indicated that high rates of SOC losses occurred in the croplands with the most common cropping patterns in China as like single soybean 〉 maize 〉 paddy 〉 cotton 〉 winter wheat and corn rotation. The results reported in this paper showed that there was still a great potential for improving SOC status in most croplands of China by adopting proper farming practices and land-use pattern. Therefore, long-term policy to protect SOC is urgently needed.

关键词： China cropland DNDC model soil organic carbon

Modeling the Impacts of Soil Organic Carbon Content of Croplands on Crop Yields in China

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Agricultural Sciences in China 2009年第4期8卷 464-471页

作者： QIU Jian-jun WANG li-gang li HU TANG Hua-jun li chang-sheng Eric Van Ranst Key Laboratory of Resources Remote Sensing and Digital Agriculture Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences (CAAS) Beijing 100081 P.R. China Institute for the Study of Earth Ocean and Space University of New Hampshire Durham NH 03824 USA Department of Geology and Soil Science (WEI3) Laboratory of Soil Science Ghent University Krijgslaan 281 (S8) B-9000 Gent Belgium

This study quantified the impacts of soil organic carbon （SOC） content on the grain yield of crops using a biogeochemical model （DNDC, denitrification-decomposition）. Data on climate, soil properties, and farming management regimes of cropping systems were collected from six typical agricultural zones （northeast, north, northwest, mid-south, east and southwest regions of China, respectively） and integrated into a GIS database to support the model runs. According to the model, if the initial SOC content in the cropland was increased by 1 g C kg^-1, the crop yield may be increased by 176 kg ha^-1 for maize in the northeast region, 454 kg ha^-1 for a maize-wheat rotation in the north region, 328 kg ha^-1 for maize in the northwest region, 185 kg ha^-1 for single-rice in the mid-south region, 266 kg ha^-1 for double-rice in east region, and 229 kg ha^-1 for rice and wheat rotation in southwest region. There is a great potential for enhancing the crop yield by improving the SOC content in each region of China.

关键词： soil organic carbon grain yield carbon sequestration DNDC model