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Search Results: 1 - 10 of 83578 matches for " Qin-Juan Xu "
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Tetraaquatetrakis{μ3-3,3′-[(E,E)-ethane-1,2-diylbis(nitrilomethylidyne)]benzene-1,2-diolato}octazinc(II) N,N-dimethylformamide hexasolvate
Qin-Juan Xu,Li-Rong Lin,Di Sun,Rong-Bin Huang
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809046923
Abstract: The asymmetric unit of the title compound [Zn8(C16H12N2O4)4(H2O)4]·6C3H7NO, consists of eight ZnII cations, four tetravalent anionic ligands, L4 (L4 = 3,3′-(1E,1′E)-(ethane-1,2-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene)dibenzene-1,2-bis(olate), four coordinated water molecules and six N,N-dimethylformamide solvate molecules. The coordination complex comprises an octanuclear ZnII unit with its ZnII centers coordinated in two discrete distorted square-pyramidal geometries. Four ZnII atoms each coordinate to two nitrogen atoms and two phenolate oxygen atoms from an individual L4 ligand and one coordinated water molecule. The other four ZnII atoms each bind to five phenolate oxygen atoms from three different L4 ligands. In the crystal structure, the ZnII complex unit, coordinated water molecules and dimethylformamide solvate molecules are linked via O—H...O and C—H...O hydrogen bonds. Molecules are connected by additional intermolecular O—H...O and C—H...O hydrogen bonds, forming an extensive three dimensional framework.
Study on sensitivity of soil surface crust formation in typical regions with serious soil and water loss, China
我国水土流失典型区土壤表土结皮敏感性

CHENG Qin-juan,CAI Qiang-guo,MA Wen-jun,
程琴娟
,蔡强国,马文军

地理研究 , 2008,
Abstract: Soil surface crust attracted great attention because of its effects on plant growth and output,and further infiltration and runoff production and sediment yield.Soil surface crust formation is the product of soil and rainfall.The sensitivity of soil crust formation depends on soil properties and rainfall characteristics;however,it is difficult to evaluate the sensitivity of soil surface crust formation because key factors of soil crust formation are still unclear.In addition,many types of soils,especially loess soil,purple soil,red soil and black soil with different physical and chemical properties are distributed spatially in serious soil and water loss regions of China,such as the Loess Plateau region and Sichuan.However,soil crust sensitivities of these regions are short of report. Based on experiment results under simulated rainfalls and conclusions of other researchers,the paper considered that fine particles,aggregate stability and high rainfall intensity are three key factors affecting soil crust formation.Among them,fine particles,especially silt particles provide material for soil crust formation.Whereas,soil particles are commonly in the pattern of aggregates,so aggregates stability decides the rate and degree of soil crust development.In addition,rainfalls with high intensity disrupt the aggregates by its impact energy and change the balance condition of soil;so,rainfalls decide whether soil surface crust develops or not. Analyzing the soil properties and rainfall characteristics,soil crust sensitivities of the above-mentioned regions are concluded.In the Loess Plateau region,silt particles are predominant,and aggregate stability is weak,whereas,rainstorms are frequent;therefore,it is sensitive for loess soil to form soil surface crust.In purple soil region,the content of silt and clay particles is more than 50%,and aggregate stability is weak due to the higher content of rock chipping;consequently,it is prone to form soil surface crust under rainfalls with high rainfall intensity.In red soil region,it is difficult to form soil surface crust except soils developed from granite and shale due to high sand particles or stable aggregates.In black soil region,it is impossible to form soil surface crust on typical black soils with aggregate content of more than 50%.However,soil crust can develop on non-typical black soils.
One new sediment yield model for single storm events and its application at annual time scale
一种新的流域水沙关系模型及其 在年际时间尺度的应用

ZHENG Ming-guo,CAI Qiang-guo,CHENG Qin-juan,
郑明国
,蔡强国,程琴娟

地理研究 , 2007,
Abstract: The loess gullied-hilly area of the Loess Plateau in North China is one of the most severely eroded regions in the world with a mean annual soil loss rate exceeding 10000t/ km^2. Based on the observed data here from two stations, the relationship between runoff and sediment yield is examined for single storm events. In the study area, sediment concentration keeps stable when flow discharges are in excess of some critical values, and mean sediment concentration for single flood events mainly depends on the heavy-discharge stage in flood duration. Thus, the mean sediment concentration also keeps stable for heavy flood events. Therefore, one new runoff-sediment relationship model is established for specific watershed. M= Ch, where M is area-specific sediment yield, h is runoff depth. Furthermore, this model has excellent applicability due to the importance of extreme events for soil loss in the study area. The results of the model applied to the annual timescale showed that the model can predict the annual sediment yield very well for the watershed without base flow; and for the watershed where base flow exists, the model can also obtain a good estimation in wet year using the total runoff volume occurred in flood season.
Resistance of Helicobacter pylori to antibiotics from 2000 to 2009 in Shanghai
Qin-Juan Sun, Xiao Liang, Qing Zheng, Wei-Qi Gu, Wen-Zhong Liu, Shu-Dong Xiao, Hong Lu
World Journal of Gastroenterology , 2010,
Abstract: AIM: To investigate the resistance of Helicobacter pylori (H. pylori) to 6 commonly used antibiotics from 2000 to 2009 in Shanghai.METHODS: A total of 293 H. pylori strains were collected from 2000 to 2009 in Shanghai and tested for their susceptibility to metronidazole, clarithromycin, amoxicillin, furazolidone, levofloxacin and tetracycline using agar dilution.RESULTS: The resistant rates of H. pylori to clarithromycin (8.6%, 9.0% and 20.7%) and levofloxacin (10.3%, 24.0% and 32.5%) increased from 2000 to 2009 in Shanghai. The resistant rate of H. pylori to metronidazole remained stable (40%-50%). Only one strain of H. pylori isolated in 2005 was resistant to tetracycline. All strains were sensitive to amoxicillin and furazolidone. The resistant rate of H. pylori to antibiotics was not related with the sex, age and clinical outcome of patients.CONCLUSION: Resistance of H. pylori to antibiotics plays an important role in making treatment strategies against H. pylori-associated diseases.
Mechanism and Performance of a Membrane Bioreactor for Treatment of Toluene Vapors
膜生物反应器处理甲苯性能及机制

YE Qi-hong,WEI Zai-shan,XIAO Pan,LI Hua-qin,ZHANG Zai-li,FAN Qin-juan,
叶杞宏
,魏在山,肖盼,李华琴,张再利,樊青娟

环境科学 , 2012,
Abstract: The performance of a membrane bioreactor for treatment of toluene as a model pollutant is presented. Effects of toluene inlet concentration, residence time, spray density and pH of liquid phase on the toluene removal rate were evaluated. The experimental results showed that the toluene removal efficiency reached 99%. The optimal pH, residence time and spray density were 7.2, 6.4 s and 2.5 m3 ·(m2 ·h)-1, respectively. The gas-phase biodegradation intermediate products were acetaldehyde acid (C2H2O3) and vinyl formic acid (C3H4O2), which were identified by means of gas chromatography/mass spectrometry (GC/MS). The mechanism of toluene degradation using a membrane bioreactor can be described as the combination of mass transfer from hollow fiber membrane to biofilm and biological degradation. Toluene (C6H5CH3) and oxygen diffused from the gas phase to the wet layer of the biofilm and were then consumed by the microbial communities. Toluene was oxidized to the intermediate organic products such as acetaldehyde acid (C2H2O3) and vinyl formic acid (C3H4O2), and the intermediate products were then converted to CO2 and H2O through continuous biological oxidation reactions.
The Correlation of Lung Function Indexes and Survival Time of Patients with Advanced Lung Cancer  [PDF]
Wenjing Xu, Zhenghua Jiang, Dongyun Huang, Muyun Zhu, Qian Huang, Hui Ge, Juan Liu, Yan Qin
Journal of Cancer Therapy (JCT) , 2013, DOI: 10.4236/jct.2013.41029
Abstract:

Background: To those patients with advanced lung cancer, the ultimate objective is to improve the quality of life, and lung function is an important factor affecting quality of life. We detect lung function of patients with lung cancer and study the correlation between lung function and the patients’ survival time, to provide reference for evaluation of disease progression and prognosis. Methods: Lung function was detected on 59 cases of lung cancer and 63 normal controls. The relationship between lung function indexes and survival time was analyzed. Results: There was significant difference in ventilation function and diffusing capacity between lung cancer group and control group. Vital capacity (VC), Forced expiratory volume in one second (FEV1), Forced vital capacity (FVC), peak expiratory flow (PEF), peak expiratory flow% (PEF%), Maximal ventilatory volume (MVV) were positively correlated to survival time in patients with advanced lung cancer (r = 0.28522064, 0.28053851, 0.28289252, 0.26908133, 0.26335034, 0.28409036, P < 0.05), residual volume/total lung capacity was negatively correlated to survival time (r = ?0.30760097, P < 0.05). Conclusions: The lung function decrease in the patients with lung cancer. Vital capacity (VC), Forced expiratory volume in one second (FEV1), Forced vital capacity (FVC), peak expiratory flow (PEF), peak expiratory flow% (PEF%), Maximal ventilatory volume (MVV), and residual volume/total lung capacity are correlated to survival time in patients with advanced lung cancer. The lung function indexes are important marker of prognosis of patients with lung

The Differences in Alcohol Use between Urban and Rural Students of Inner Mongolia Medical University, China  [PDF]
Zhihui Hao, Peng Qin, Yongjun Xu, Qingxia Wang, Hairong Zhang, Yun Li, Yueling Hu, Xiaodong Bi, Juan Sun
Open Journal of Epidemiology (OJEpi) , 2016, DOI: 10.4236/ojepi.2016.62014
Abstract: Objective: The purpose of this study was to evaluate the difference in alcohol use between urban and rural students of Inner Mongolia Medical University. Methods: A cross-sectional census was conducted on medical students on campus in 2013. We use multivariate logistic regression models to assess the factors associated with alcohol use. We further use chi-square test assess on differences in alcohol use between urban and rural people among significance factors in logistic regression models. Results: The prevalence of alcohol use among students in rural area was higher than that in urban area (p = 0.016). Alcohol use was associated with Gender, monthly expenses, residence, ethnic and faculty. The odds of alcohol use for Mongolia students were 1.139 times higher than that for Han students. The prevalence of alcohol consumption among students from pharmacy or Traditional Chinese Medicine and Mongolian Medicine faculties in rural area was higher than that among student in urban area (p = 0.03; p = 0.001). The prevalence of alcohol use among female students in rural area was higher than that among female students in urban area (p < 0.043). The proportion of alcohol use among students with <600 in rural area was higher than that among students in urban area (p < 0.001). Conclusion: Considering the differences in the prevalence of alcohol use between rural area and urban area, university administrators aiming at students from various regions develop various approaches.
Cloud and Open BIM-Based Building Information Interoperability Research  [PDF]
Du Juan, Qin Zheng
Journal of Service Science and Management (JSSM) , 2014, DOI: 10.4236/jssm.2014.72005
Abstract:

The emergence of Open BIM effectively improves the interoperability of building information. Besides, cloud technology supports virtualization and QoA (Quality of Assurance) in the case of the distributed system and multi-user collaboration. Based on the cloud and the Open BIM, this paper puts forward the cloud services models and the cloud-based Open BIM building information interaction framework, and further illustrates the architecture of cloud deployment pattern and the information interaction process. Finally, the paper takes underground rail transit project as example and explains how to deploy and implement the tunnel construction management platform.

Algorithm Design and Simulation of the Urban Rail Turn-Back Capacity Based on CBTC  [PDF]
Jikang Xu, Qin Luo
Journal of Computer and Communications (JCC) , 2015, DOI: 10.4236/jcc.2015.36003
Abstract: In order to analyze the turn-back capacity of urban rail transit based on CBTC more accurately, firstly, this paper analyzes the turn-back process and characteristics, and the factors that influence the turn-back interval time. Secondly, it respectively analyzes various influence factors and designs algorithm. Then, it designs algorithm and developed computer simulation system (TBSim) for calculating the turn-back capacity based on CBTC and the traction calculation. Finally, it proves the correctness and practicability of the algorithm and the simulation system by an example.
A New Method of Measuring the Plastic Deformation
一种检测塑性变形的新方法

CHEN Ding,FENG Juan,XU Bo-qin,
陈丁
,冯娟,续伯钦

实验力学 , 2006,
Abstract: Roughness on the metal specimen polished surface will be induced when it yields plastic deform or fatigue damage for its interior microscopic crystal grain slip dislocation,and this is very different when it yields elastic deform.Its specula reflection weakened while scattering reflection reinforced.This paper presented a new technique to determine the elastic-plastic boundary and plastic strains on the surface of metal specimen.The metal specimen subjected uniform tension is projected by Slant incident white-light;loads increase as preseted.These distributions of the brightness can be recorded as real-time images by CCD camera.The following simple method we advanced is used to analysis the image data.According the practical situation,one threshold is chosen.The gray level which is greater that the threshold is defined the bright point.Define BI as the reciprocal value of the number of the bright points.In the experiments,BI keeps stable during the period of elasticity;while the material is yielding,the increase of the surface roughness leads to the stronger ability of the random reflection;and the BI goes down sharply.BI keeps monotone decreasing during the period of plasticity.So BI can be taken as a feature parameter.BI can not only be used as a judgment of the status but also be the measuring of the plasticity.Typical experiments can verify the method.The conclusion matches the traditional correlation method very well.This method can be prospectively applied in the engineering with the merit of simple operation and low environmental condition.This paper also discusses a parameter which is very important to the accuracy of this method.Based on the analysis of the data,a method which is called confidence interval was developed to determine the threshold value.And also find that the better results can be obtained with the little of the confidence interval.
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