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Hydroxylation Reaction Mechanism for Nitrosodimethylamine by Oxygen Atom

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Chemical Research in Chinese Universities 2011年第6期27卷 1006-1009页

作者： LI Lan lin xiao-yan LI Zong-he College of Sciences Shanghai Institute of Technology Shanghai 200235 P. R. China College of Chemistry Beijing Normal University Beijing 100875 P. R. China

The hydroxylation reaction mechanism of nitrosodimethylamine（NDMA） by oxygen atom was theoretically investigated at the B3LYP/6-31G＊＊ level. It has been found that the path of the oxydation of the C―H bond is easier than the path involving a Singlet/Triplet crossing. The study of the potential surface shows that both solvent effect at B3LYP/6-31G＊＊ level and different method at more credible MP2/6-311G＊＊ level in the gas phase have no effect on the hydroxylation reaction mechanism. The oxidation hydroxylation process of NDMA by O is exothermic reaction and easy to occur.

关键词： Nitrosodimethylamine(NDMA) Hydroxylation B3LYP MP2

Inversion analysis of the shear strength parameters for a high loess slope in the limit state

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Journal of Mountain Science 2021年第1期18卷 252-264页

作者： lin xiao-yan ZHANG lin-fan yanG Ze LI Ping LI Tong-lu School of Earth Sciences and Engineering Xi'an Shiyou UniversityXi'an 710065China Shaanxi Key Laboratory of Petroleum Accumulation Geology Xi'an Shiyou UniversityXi'an 710065China School of Geological Engineering and Surveying Chang'an UniversityXi'an 710061China

It is difficult to obtain reliable shear strength parameters for the stability analysis and evaluation of high loess ***,this paper determines slope elements and physical parameter of 79 slopes with heights of[40,120]m based on the measured loess slopes in the Ganquan and Tonghuang subregions of northern Shaanxi Province,*** the limit state of the loess slope(stability factor Fs is 1.0),a fitting equation for the slope height and width is ***,the model is developed by stability analysis software-SLOPE/W,and the comprehensive shear strength parameters corresponding to different slope heights of the high slope in the study area are obtained by inversion using the Morgenstern-Price *** results show that when the height of the slope increases,the cohesion c increases in the soil,and the internal friction angle j *** change is consistent with the characteristics reflected in the composition and physical properties of the slopes,and the comprehensive strength parametric curves are very similar between the Ganquan subregion and the Tonghuang subregion.A landslide that occurred in Miaodian-zaitou of Jingyang County,Shaanxi Province,is selected to verify this inversion method,and the results show that the calculated shear strength parameters of the inversion are consistent with the measured value of the actual slope.

关键词： Loess High slope Shear strength Inversion SLOPE/W

A sparse matrix model-based optical proximity correction algorithm with model-based mapping between segments and control sites

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第5期12卷 436-442页

作者： Bin lin xiao-lang yan Zheng SHI Yi-wei yanG Institute of VLSI Design Zhejiang University Hangzhou 310027 China

Optical proximity correction (OPC) is a key step in modern integrated circuit (IC) *** quality of model-based OPC (MB-OPC) is directly determined by segment offsets after OPC ***,in conventional MB-OPC,the intensity of a control site is adjusted only by the movement of its corresponding segment;this scheme is no longer accurate enough as the lithography process *** the other hand,matrix MB-OPC is too time-consuming to become *** this paper,we propose a new sparse matrix MB-OPC algorithm with model-based mapping between segments and control *** put forward the concept of 'sensitive area'.When the Jacobian matrix used in the matrix MB-OPC is evaluated,only the elements that correspond to the segments in the sensitive area of every control site need to be calculated,while the others can be set to *** new algorithm can effectively improve the sparsity of the Jacobian matrix,and hence reduce the *** theoretical analysis and experiments show that the sparse matrix MB-OPC with model-based mapping is more accurate than conventional MB-OPC,and much faster than matrix MB-OPC while maintaining high accuracy.

关键词： Matrix sparsity Optical proximity correction (OPC) Convergence Segment Sensitive area

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铁路旅客期望与旅客满意关系研究

铁道学报 2010年第4期32卷 23-26页

作者：陈小君林晓言北京交通大学经济管理学院北京100044

客运服务质量优劣取决于旅客对服务预期和实际感知之间的对比,从某种意义上讲,服务质量可以认为是主观范畴。由此引来对客运企业质量优劣的评价在很大程度上由旅客期望所决定。本文首先探讨顾客期望及满意含义。接着在此基础上,说明旅... 详细信息

客运服务质量优劣取决于旅客对服务预期和实际感知之间的对比,从某种意义上讲,服务质量可以认为是主观范畴。由此引来对客运企业质量优劣的评价在很大程度上由旅客期望所决定。本文首先探讨顾客期望及满意含义。接着在此基础上,说明旅客期望和旅客满意的对应关系。并利用博弈的方法推导出铁路客运服务业中旅客满意的一般均衡条件。最后基于该均衡条件,铁路客运企业可以通过合理引导旅客期望,进而使得旅客满意。

关键词：铁路旅客期望铁路旅客满意顾客期望层次信息不对称

基于灰色-马尔可夫链改进方法的铁路货运量预测研究

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铁道学报 2005年第3期27卷 15-19页

作者：林晓言陈有孝北京交通大学基础产业研究中心北京100044

科学的预测对于经济现象的研究和经济决策的制定都具有十分重要的意义,因此,关于经济预测理论和方法的研究一直是一个热点。本文将灰色模型预测方法GM(1,1)和马尔可夫链预测相结合,提出灰色马尔可夫链改进预测方法,并且针对我国铁路货... 详细信息

科学的预测对于经济现象的研究和经济决策的制定都具有十分重要的意义,因此,关于经济预测理论和方法的研究一直是一个热点。本文将灰色模型预测方法GM(1,1)和马尔可夫链预测相结合,提出灰色马尔可夫链改进预测方法,并且针对我国铁路货运量的发展趋势进行了预测,得出比灰色预测更加准确的结论。从而证明,灰色马尔可夫链改进方法的预测结果更加准确可靠,更有利于决策者的经济决策行为。

关键词：经济预测铁路货运量灰色预测马尔可夫链灰色-马尔可夫链改进方法

Isolation and Characterization of a Bensulfuron-Methyl-Degrading Strain L1 of Bacillus

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Pedosphere 2010年第1期20卷 111-119页

作者： lin xiao-yan WANG Yi WANG Hai-Long T. CHIRKO DING Hai-Tao ZHAO Yu-Hua Department of Microbiology College of Life Sciences Zhejiang University Hangzhou 310058 (China) China National Rice Research Institute Hangzhou 310006 (China) Ensis Rotorua Private Bag 3020 (New Zealand) College of Environmental Sciences and Technology Zhejiang Forestry University Lin'an 311300 (China)

The objectives of this study were to isolate a bensulfuron-methyl （BSM）-degrading strain of Bacillus spp. and to evaluate its effectiveness in remediation of a BSM-contaminated soil. A BSM-degrading bacterium, strain L1, was successfully isolated in this study. Strain L1 was identified as Bacillus megaterium based on its morphological, physiological, and biochemical properties, G＋C content, phylogenetie similarity of 16S rDNA, and fatty acid composition. Two experiments were used to examine BSM degradation by strain L1. When BSM was used as a sole carbon source in a mineral salt medium, the average degradation rate of BSM by strain L1 was 12.8%, which suggested that the strain was able to utilize BSM as a sole carbon and energy source. Supplement of yeast extract （200 mg L^-1） significantly （P ≤ 0.01） accelerated the degradation of BSM by strain L1. Ahnost complete degradation （97.7%） of BSM could be achieved in 84 h with addition of yeast extract. In addition, in a sterile soil with 50 mg L^-1 BSM, BSM degradation rate by strain L1 was 94.3% in 42 d, indicating the potential of using microbes for the remediation of BSM-contaminated soils in fields.

关键词： biodegradation carbon source phylogenetic analysis 16S rDNA

Effect of heparin on high glucose induced proliferation and expression of matrix metalloproteinases in normal human mesangial cells

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Journal of Central South University of Technology 2005年第Z1期12卷 359-364页

作者： ZHOU Qiao-ling Yasumoto Yuichiro Tsukamoto Masatoshi Nozaki Tsuyoshi Sogabe Atsushi Harada Kouji ZHANG Yi-xiang lin xiao-yan ZHANG yang-de Arima Terukatsu Second Department of Internal Medicine Kagoshima University Kagoshima Japan Department of Nephrology Xiangya Hospital Central South University Changsha 410008 China Second Department of Internal Medicine Kagoshima University Kagoshima Japan Second Department of Internal Medicine Kagoshima University Kagoshima Japan Second Department of Internal Medicine Kagoshima University Kagoshima Japan Second Department of Internal Medicine Kagoshima University Kagoshima Japan Second Department of Internal Medicine Kagoshima University Kagoshima Japan Second Department of Internal Medicine Kagoshima University Kagoshima Japan Second Department of Internal Medicine Kagoshima University Kagoshima Japan Department of Nephrology Xiangya Hospital Central South University Changsha 410008 China Second Department of Internal Medicine Kagoshima University Kagoshima Japan

Background The pathogenesis of diabetic nephropathy (DN) is a complex pathophysiological *** precise mechanism is not fully known. In recent years it has been recognized that synthesis of various extracelluar matrix (ECM) components may increase, and that degradation of ECM may decrease in DN. It was reported heparin could inhibit mesangial cells proliferation in vitro. The main aim of this study is to explore whether heparin inhibits proliferation of mesangial cells grown in high glucose concentration and to measure the effect of heparin on matrix metalloproteinases (MMPs) expression in mesangial cells. Methods The medium contained either low glucose (5 mmol/L) or high glucose (25 mmol/L). The concentrations of heparin in the culture medium were 0, 25, 50,100, 200 or 400 μg/mL. A metabolic (WST-1) assay was used to measure mesangial cell proliferation and Western blot analysis was used to measure MMPs expression of mesangial cells. Results Normal human mesangial cell (NHMC) proliferation was higher in high glucose (HG) medium than in low glucose (LG) medium. They showed a 1.93 fold expansion after 72 h in high glucose in contrast to a 1.63 fold expansion in low glucose. In the presence of heparin, mesangial cells proliferation was inhibited, which was more obvious at high glucose concentrations than at low glucose concentrations. In high glucose, with heparin concentration of 50, 100, 200 and 400 μg/mL, the mesangial cells showed a 0. 61 fold, 0.52 fold, 0.52 fold and 0.41 fold reductions in cell number compared to cells grown without heparin. In low glucose, only concentrations of 200 μg/mL and 400 μg/mL showed reduction in cell number, namely 0.54 fold and 0.45 fold, when compared to cells grown without heparin. In Western blot analysis,MMP1, MMP2, MMP3 and MMP9 was expressed by mesangial cells expressed in both high and low glucose concentrations, which was more prominent in high glucose medium. Incubation of heparin further increased expression of MMP1,

关键词： matrix metalloproteinases normal human mesangial cell glucose heparin

Role of adjuvant chemoradiotherapy in treatment of resectable esophageal carcinoma： a meta-analysis

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Chinese Medical Journal 2013年第6期126卷 1178-1182页

作者： ZHENG Bin ZHENG Wei ZHU Yong lin xiao-yan XU Ben-hua CHEN Chun Department of Thoracic Surgery Department of Radiotherapy (Xu BH) Fujian Medical University Union Hospital Fuzhou Fujian 350001 China Department of Chemotherapy Department of Radiotherapy (Xu BH) Fujian Medical University Union Hospital Fuzhou Fujian 350001 China

Background The effectiveness and influence of surgery followed by adjuvant chemoradiotherapy （CRT） on the survival of patients with resectable esophageal carcinoma are still under debate. The outcomes of clinical trials have not been consistent. This study aimed to perform a meta-analysis of eligible published clinical trials to compare CRT with surgery without adjuvant chemoradiotherapy （non-CRT） for resectable esophageal carcinoma. Methods Computerized bibliographic and manual searches were undertaken to identify all eligible literature between 1990 and 2012. PubMed, EMBASE, Chinese National Knowledge Infrastructure, and Wanfang databases were our primary sources for published clinical trials. The quality of the methodology and reliability of the data from all of the clinical trials were assessed. All data were extracted by three independent researchers. Results Seven studies that included a total of 523 patients were selected. It was found that CRT significantly improved survival. The odds ratio （OR） in comparing CRT and non-CRT groups was 1.75 （95% confidence intervals （CI）： 1.17-2.60, P=0.006） for 1-year survival, 2.07 （95% CI： 1.45-2.96, P 〈0.0001） for 3-year survival, and 2.17 （95% CI： 1.45-3.26, P=0.0002） for 5-year survival. There have been no CRT treatment-related deaths reported in the literature. The incidence of related complications was high in the cases with CRT. Patients treated with CRT had a lower incidence of local-regional cancer recurrence （OR： 0.49, 95% CI： 0.31-0.76, P=0.002） and a similar incidence of distant cancer recurrence （OR： 0.90, 95% CI： 0.60-1.34, P=0.60）. Conclusions It was found that patients with resectable esophageal carcinoma could gain a survival benefit from CRT. However, CRT was associated with a high incidence of related complications.

关键词： esophageal carcinoma adjuvant treatment chemoradiotherap meta-analysis

Long-term efficacy of excimer laser in situ keratomileusis in the management of children with high anisometropic amblyopia

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Chinese Medical Journal 2009年第7期122卷 813-817页

作者： lin xiao-ming yan xiao-he WANG Zheng yanG Bin CHEN Qi-wen SU Jin-ai YE Xue-lian State Key Laboratory of Ophthalmology Zhongshan OphthalmicCenter Sun Yat-sen University Guangzhou Guangdong 510060China

Background Children with anisometropic amblyopia are often noncompliant with traditional treatment including spectacules and contact lenses. This study was to evaluate the long-term efficacy of excimer laser in situ keratomileusis （LASIK） for children with high anisometropic amblyopia. Methods A retrospective analysis of 24 children with high unilateral anisometropic amblyopia, who underwent LASIK during the period between August 2000 and September 2005 in our hospital, was conducted. The mean age of these children was （7.4±1.9） years （range 5-14 years） and the mean follow-up period was （33.3±14.2） months （range 18.5-74.2 months）. After LASIK, visual acuity, refraction and far or near stereoacuity were analyzed. Near stereoacuity was measured by the random-dot butterfly stereogram and the pre-school random-dot stereogram, while far stereoacuity was measured by the synoptophore with yan＇s random-dot stereogram. Results Mean preoperative uncorrected visual acuity was 0.06±0.05, while mean postoperative uncorrected visual acuity was elevated to 0.43±0.33. Mean preoperative best-corrected visual acuity was 0.26±0.22, while mean postoperative best-corrected visual acuity was elevated to 0.67±0.40. For patients with myopic anisometropia, preoperative mean spherical equivalent refraction was （-8.01±2.70） D while postoperative value significantly reduced to （-1.32±2.47） D. For patients with hyperopic anisometropia, preoperative mean spherical equivalent refraction was （ 7.35±1.55） D while postoperative value significantly reduced to （3.30±0.86） D. These results demonstrated that there was statistical difference in these parameters between preoperative and postoperative tests. At the last follow-up, 20 patients had near stereoacuity, and the mean near stereoacuities measured by the random-dot butterfly stereogram and the preschool random-dot stereogram were （149.00±152.93）＂ and （201.05±235.94）＂, respectively. In contrast, 11 patients had far stereoacuity, and the mean far

关键词： excimer laser in situ keratomileusis amblyopia children anisometropia