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Soot particle distributions inside a diesel particulate filter during soot loading in plateau environment

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Journal of Central South University 2022年第7期29卷 2201-2212页

作者： WANG Peng BI yu-hua SHEN Li-zhong LEI Ji-lin yu feng-rong yunnan Province Key Laboratory of Internal Combustion Engines Kunming University of Science and TechnologyKunming 650500China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650500China

A three-dimensional diesel particulate filter(DPF)simulation model was developed by using AVL software FIRE to study the effects of four factors on soot particle distributions along the axial and radial directions in the DPF after the model accuracy was *** orthogonal test method was used to determine the importance and weights of the design of experiments(DoE)factors such as the expanding angle,the number of channels per square inch,and the exhaust mass flow *** effects of these factors on the uniformity of the soot particle distributions were also *** results show that when the soot loading time was 400 s,the soot particles inside the DPF along the axial direction exhibited a bowl shape,which was high on the both ends and low in the *** uniformity of the axial distribution of soot particles reduces significantly with an increase in the number of channels per square *** uniformity of the radial distribution reduced with an increase in the expanding angle of the divergent *** on the impacts on the axial uniformity,the three most influencing factors in a descending order are the number of channels per square inch,the exhaust mass flow rate,and the expanding angle of the divergent tube.

关键词： diesel particulate filter(DPF) soot particle distribution plateau environment pressure loss

Folate levels in mucosal tissue but not methylenetetrahydrofolate reductase polymorphisms are associated with gastric carcinogenesis

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World Journal of Gastroenterology 2006年第47期12卷 7591-7597页

作者： yu-rong Weng Dan-feng Sun Jing-yuan Fang wei-Qi Gu Hong-Yin Zhu Shanghai Institute of Digestive Disease ShanghaiJiao-Tong University School of Medicine Renji HospitalShanghai 200001 China

AIM: To evaluate whether folate levels in mucosal tissue and some common methylenetetrahydrofolate reductase (MTHFR) variants are associated with the risk of gastric cancer through DNA methylation. METHODS: Real-time PCR was used to study the expression of tumor related genes in 76 mucosal tissue samples from 38 patients with gastric cancer. Samples from the gastroscopic biopsy tissues of 34 patients with chronic superficial gastritis (CSG) were used as controls. Folate concentrations in these tissues were detected by the FOL ACS: 180 automated chemiluminescence system. MTHFR polymorphisms were analyzed by PCR-RFLP, and the promoter methylation of tumor-related genes was determined by methylation-specific PCR (MSP). RESULTS: Folate concentrations were significantly higher in CSG than in cancerous tissues. Decreased expression and methylation of c-myc accompanied higher folate concentrations. Promoter hypermethylation and loss of p16INK4A in samples with MTHFR 677CC were more frequent than in samples with the 677TT or 677CT genotype. And the promoter hypermethylation and loss of p21WAF1 in samples with MTHFR 677CT were more frequent than when 677CC or 677TT was present. The 677CT genotype showed a non-significant higher risk for gastric cancer as compared with the 677CC genotype. CONCLUSION: Lower folate levels in gastric mucosal tissue may confer a higher risk of gastric carcinogenesisthrough hypomethylation and overexpression of c-myc.

关键词： Folate Methylenetetrahydrofolate reductase Polymorphism DNA methylation Gastric cancer

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang feng Gao yu-Gui Peng Peng Wu Zong-Lin Li Xue-feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

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基于地学信息图谱的东北黑土区种植模式分析

应用生态学报 2022年第3期33卷 694-702页

作者：杜国明张瑞于凤荣东北农业大学公共管理与法学院哈尔滨150030 东北农业大学经济管理学院哈尔滨150030 黑龙江省农垦科学院科技情报研究所哈尔滨150038

不同种植模式具有不同的经济学和生态学意义,因地制宜确立合理的种植模式是保护黑土地的重要措施。目前,对东北黑土区的种植模式类型及其空间格局尚缺乏系统的认识。本研究基于东北黑土区2017—2019年作物分类数据,应用地学信息图谱理... 详细信息

不同种植模式具有不同的经济学和生态学意义,因地制宜确立合理的种植模式是保护黑土地的重要措施。目前,对东北黑土区的种植模式类型及其空间格局尚缺乏系统的认识。本研究基于东北黑土区2017—2019年作物分类数据,应用地学信息图谱理论和方法构建种植模式图谱,以揭示黑土区种植模式类型及其空间格局,并在此基础上使用分布指数模型和双变量空间自相关方法分析了种植模式的分布规律。结果表明:1)东北黑土区种植模式主要有玉米连作、水稻连作、大豆连作和米(玉米)豆(大豆)轮作,面积占比分别为38.3%、18.5%、10.3%、26.0%。其中,米豆轮作又包括米豆两年轮作、米米豆三年轮作、豆豆米三年轮作,分别占轮作面积的44.1%、34.5%、21.4%;2)各类种植模式的水平地带性分异规律显著。其中,玉米连作在温度和湿度上的梯度分异特征均非常明显,水稻连作仅在湿度上的梯度分异特征非常明显,大豆连作和米豆轮作在温度和湿度上的梯度分异特征均不明显;3)各类种植模式的空间集聚特征显著,种植模式间存在"大豆连作→豆豆米三年轮作→米豆两年轮作→米米豆三年轮作→玉米连作"的空间过渡特征。东北黑土区种植模式以连作为主,其分布规律可为今后轮作空间优化提供依据。

关键词：东北黑土区种植模式地学信息图谱种植模式图谱

Risk factors for bronchiolitis obliterans syndrome in allogeneic hematopoietic stem cell transplantation

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Chinese Medical Journal 2013年第13期126卷 2489-2494页

作者： MO Xiao-dong XU Lan-ping LIU Dai-hong ZHANG Xiao-hui CHEN Huan CHEN yu-hong HAN Wei WANG yu WANG feng-rong WANG Jing-zhi LIU Kai-yan HUANG Xiao-jun Peking University People's Hospital & Institute of Hematology Beijing Key laboratory of Hematopoitic Stem Cell Transplantation Beijing 100044 China

Background The occurrence of bronchiolitis obliterans syndrome （BOS） after allogeneic hematopoietic stem cell transplantation （alIo-HSCT） is rare but severe. We examine the role of pre-HSCT chemotherapeutic exposure, pre-HSCT comorbidities, and transplant-related complications in the development of BOS after alIo-HSCT. Methods A nested case-control study was designed. Cases with BOS and controls matched for the year of alIo-HSCT and length of the follow-up were identified from a cohort of 1646 patients who underwent alIo-HSCT for treatment of hematologic malignancies between 2006 and 2011. Antithymocyte globulin was used in the partial matched related and unrelated matched donor HSCT, or patients with severe aplastic anemia. Results Thirty-six patients suffered from BOS; the mean age at the time of presentation was （32.7±2.4） years, and the mean time to presentation was （474±350） days post-HSCT. A pre-HSCT cyclophosphamide dose of 〉3.2 g/m2 （OR=8.74, P=0.025）, chronic graft-versus-host disease （moderate to severe）（OR=12.02, P=0.000）, and conditioning regimens without antithymocyte globulin （OR=2.79, P=0.031） were independently associated with BOS. Conclusions We found that higher pre-HSCT cyclophosphamide exposure, a conditioning regimen without antithymocyte globulin, and moderate to severe chronic graft-versus-host disease are significantly and independently associated with BOS. Based on these results, we can identify patients who are at a higher risk of developing BOS after alIo-HSCT, select a more appropriate therapeutic strategy, and improve the outcome of HSCT recipients.

关键词： bronchiolitis obliterans syndrome allogeneic hematopoietic stem cell transplantation graft-versus-host disease,"antithymoeyte globulin

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水力机组制动过程的分段递推数值解法

计算力学学报 2013年第S1期30卷 29-34页

作者：张成立曾云于凤荣昆明理工大学冶金与能源学院昆明650093 昆明理工大学工程力学系昆明650500

水力机组制动过程的数学模型为非线性一阶常微分方程,目前尚不法得到该方程的精确解析解.本文提出的分段递推法通过对该方程在小分段内进行合理的线性化处理,用拉普拉斯数学变换求出小分段内的近似解析解,得到递推算式,利用递推算式得... 详细信息

水力机组制动过程的数学模型为非线性一阶常微分方程,目前尚不法得到该方程的精确解析解.本文提出的分段递推法通过对该方程在小分段内进行合理的线性化处理,用拉普拉斯数学变换求出小分段内的近似解析解,得到递推算式,利用递推算式得到全部数值解。使用分段递推法对XAJ水力机组在各种制动方式下进行数值求解,得到了制动过程,并分析了各种制动方式的特点.同时,在自由制动和飞逸过程时与龙格—库塔法进行了比较,并在电气制动时用实验数据进行了验证.结果显示分段递推法是精确的,能满足科学研究和工程应用需要,是求解类似方程的一种简便通用方法。

关键词：非线性微分方程线性化分段法递推法

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Chinese Medical Journal 2013年第16期126卷 3048-3052页

作者： MO Xiao-dong XU Lan-ping LIU Dai-hong CHEN yu-hong ZHANG Xiao-hui CHEN Huan HAN Wei WANG yu WANG feng-rong WANG Jing-zhi LIU Kai-yan HUANG Xiao-jun Peking University People's Hospital & Institute of Hematology Beijing Key laboratory of Hematopoitic Stem Cell TransplantationBeijing 100044 China

Background Chronic graft-versus-host disease （GVHD）,the commonest long-term complication after allogeneic hematopoietic stem cell transplantation （HSCT）,has a negative impact on patients＇ health related quality of life （HRQoL）.This study was designed to investigate the HRQoL in patients with chronic GVHD in *** Two hundred and sixty-four patients with chronic GVHD who were ＞24 months post-HSCT and had been in continuous complete remission since HSCT were enrolled in this retrospective *** was evaluated using an SF-36 *** analysis was used to identify the factors that affect HRQoL in patients with chronic *** HRQoL in patients categorized as having mild and moderate chronic GVHD was significantly better than in those in the severe *** the moderate chronic GVHD category,markedly poorer HRQoL was observed in patients with both multiple organ involvement and more severe organ impairment than in those without these *** to multivariate analysis,chronic GVHD severity had the greatest significant negative impact on patients＇ HRQoL; whereas being female was associated with a negative impact on psychological *** Chronic GVHD severity strongly correlates with negative impacts on patients＇ HRQoL.

关键词： chronic graft-versus-host disease health related quality of life National Institutes of Health consensus criteria

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“十一五”淳安蚕业发展思考

蚕桑通报 2007年第1期38卷 27-29页

作者：余荣峰浙江省淳安县茧丝绸总公司浙江淳安311700

“十五”期间淳安蚕业快速发展,有效地促进了农民增收并推动了当地丝绸工业的发展。“十一五”时期淳安蚕业面临极为难得的发展机遇。如何把握机遇,顺势而上,推进淳安蚕业健康持续快速发展？笔者在总结分析“十五”期间我县蚕业发展经... 详细信息

“十五”期间淳安蚕业快速发展,有效地促进了农民增收并推动了当地丝绸工业的发展。“十一五”时期淳安蚕业面临极为难得的发展机遇。如何把握机遇,顺势而上,推进淳安蚕业健康持续快速发展？笔者在总结分析“十五”期间我县蚕业发展经验和不足的基础上,对“十一五”淳安蚕业的发展进行了思考。

关键词： “十一五” 蚕业发展 “十五”期间丝绸工业农民增收发展经验

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基于价值链模型的项目生命周期管理研究

技术与创新管理 2012年第4期33卷 406-408,413页

作者：荣玉凤中粮生物化学(安徽)股份有限公司生物技术研究中心安徽蚌埠233010

项目生命周期管理如何创造价值是项目管理实践面临的重大问题。为了有效揭示项目生命周期管理的内在作用机理,把价值链的概念引入项目管理,建立项目生命周期管理价值链模型,分析了项目生命周期内价值源泉、价值创造、价值评价及价值分... 详细信息

项目生命周期管理如何创造价值是项目管理实践面临的重大问题。为了有效揭示项目生命周期管理的内在作用机理,把价值链的概念引入项目管理,建立项目生命周期管理价值链模型,分析了项目生命周期内价值源泉、价值创造、价值评价及价值分配的全过程,结果表明,项目发展的全过程贯穿着价值的流动,项目生命周期的每个阶段都要围绕价值的流动开展项目管理工作。

关键词：项目生命周期管理价值链模型