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液膜法快速稀土二分组的研究 被引量:8
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作者 马湘江 王向德 +1 位作者 万印华 张秀娟 《稀有金属与硬质合金》 CAS CSCD 1993年第1期10-16,共7页
本文首次报道了用液膜法直接自离子矿的电解质浸渗液进行稀土分组的实验室研究。结果表明,以HDEHP作载体,LMS-2作表面活性剂,盐酸作内水相的液膜体系,对于含3%硫酸铵的离子型稀土矿浸渗液(其中加入适量络合剂X)有良好的分组效果。按... 本文首次报道了用液膜法直接自离子矿的电解质浸渗液进行稀土分组的实验室研究。结果表明,以HDEHP作载体,LMS-2作表面活性剂,盐酸作内水相的液膜体系,对于含3%硫酸铵的离子型稀土矿浸渗液(其中加入适量络合剂X)有良好的分组效果。按最佳操作条件经两级间歇式液膜分组处理,萃余液中重稀土组Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu的含量大于99.52%,内水相中Y及轻稀土La、Ce、Pr、Nd的含量大于99.98%,均已达到稀土工厂中用萃取法分组的标准。整个过程仅需30分钟,试剂消耗少,操作费用低,是深度开发离子型稀土矿以及对其它来源的混合稀土稀溶液进行深加工的一项有明显应用前景的新方法。 展开更多
关键词 稀土 二分组 液膜法 研究
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基于合作-竞争关系马尔可夫切换下异质多智能体系统均方二分组一致研究
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作者 蒲兴成 张玲侠 《智能系统学报》 CSCD 北大核心 2023年第4期803-812,共10页
针对马尔可夫切换下离散和连续异质多智能体系统均方二分组一致问题,本文分别构造了2类包含合作竞争关系和马尔可夫切换拓扑结构异质多智能体系统均方二分组一致协议。利用随机不可约非周期矩阵(stochastic indecomposable and aperiodi... 针对马尔可夫切换下离散和连续异质多智能体系统均方二分组一致问题,本文分别构造了2类包含合作竞争关系和马尔可夫切换拓扑结构异质多智能体系统均方二分组一致协议。利用随机不可约非周期矩阵(stochastic indecomposable and aperiodic matrices,SIA)相关性质、图论代数和矩阵分析等理论,得到相关系统实现均方二分组一致的充分必要条件。仿真实例说明了理论结果的有效性。 展开更多
关键词 多智能体 马尔可夫 异质系统 切换网络 合作竞争关系 随机不可约非周期矩阵 均方二分组一致性 控制协议
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非相参三点源有源诱偏下ARM弹着点研究 被引量:2
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作者 李文军 李彦松 +1 位作者 王维金 王光辉 《现代防御技术》 北大核心 2014年第5期102-107,共6页
非相参多点源诱偏技术是对抗反辐射导弹(ARM)的有效手段。以ARM目标分辨的二分组理论和双点源诱偏的仿真结果为依据,对等功率三点源诱偏的2种经典布局的ARM落点整体分布进行预测。通过对ARM落点和系统被击中概率曲线的分析及拟合处理,... 非相参多点源诱偏技术是对抗反辐射导弹(ARM)的有效手段。以ARM目标分辨的二分组理论和双点源诱偏的仿真结果为依据,对等功率三点源诱偏的2种经典布局的ARM落点整体分布进行预测。通过对ARM落点和系统被击中概率曲线的分析及拟合处理,验证了预测的正确性及系统被击中概率与占地面积的相关性,为通信辐射源抗ARM的布设提供一定的参考。 展开更多
关键词 反辐射导弹 非相参诱偏 二分组 大概率落点覆盖范围 数据拟合
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非相参三点源有源诱偏下反辐射导弹落点分布研究
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作者 李文军 李彦松 +1 位作者 王维金 王光辉 《云南民族大学学报(自然科学版)》 CAS 2014年第1期66-70,共5页
多点源诱偏技术是对抗反辐射导弹(ARM)的有效手段.以ARM攻击过程的二分组理论和双点源诱偏的仿真结果为依据,对等功率三点源诱偏的2种经典布局ARM落点整体分布进行分析和预测.通过对仿真所得ARM落点图及其几何处理结果进行对照分析,验... 多点源诱偏技术是对抗反辐射导弹(ARM)的有效手段.以ARM攻击过程的二分组理论和双点源诱偏的仿真结果为依据,对等功率三点源诱偏的2种经典布局ARM落点整体分布进行分析和预测.通过对仿真所得ARM落点图及其几何处理结果进行对照分析,验证了这种分析和预测的正确性,为通信辐射源附近的物资、人员的布设提供一定的参考. 展开更多
关键词 反辐射导弹 非相参诱偏 二分组 落点
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A Broadband Long-Wavelength Superluminescent Diode Based on Graded Composition Bulk InGaAs
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作者 丁颖 王圩 +2 位作者 阚强 王宝军 周帆 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第12期2309-2314,共6页
A novel unselective regrowth buried heterostructure long-wavelength superluminescent diode (SLD) with a graded composition bulk InGaAs active region is developed by metalorganic vapor phase epitaxy (MOVPE). At a 1... A novel unselective regrowth buried heterostructure long-wavelength superluminescent diode (SLD) with a graded composition bulk InGaAs active region is developed by metalorganic vapor phase epitaxy (MOVPE). At a 150mA injection current, the full width at half maximum of the emission spectrum of the SLD is about 72nm, ranging from 1602 to 1674nm. The emission spectrum is smooth and flat. The ripple of the spectrum is less than 0.3dB at any wavelength from 1550 to 1700nm. An output power of 4.3mW is obtained at a 200mA injection current under continuous-wave operation at room temperature. This device is suitable for the applications of light sources for gas detectors and L-band optical fiber communications. 展开更多
关键词 BROADBAND superluminescent diodes graded composition buried hetero-structure
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Molecular Genetic Diagnostics of Prader-Willi Syndrome:a Validation of Linkage Analysis for the Chinese Population 被引量:1
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作者 李洪义 孟舒 +8 位作者 陈争 李海飞 杜敏联 马华梅 魏海云 段红蕾 郑辉 闻人庆 宋新明 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第10期885-891,共7页
Prader-Willi Syndrome (PWS) is a genetic disorder that is difficult to detect, particularly at an early age. PWS is caused by disruption of normal, epigenetically controlled gene function in the chromosome 15q11-q13... Prader-Willi Syndrome (PWS) is a genetic disorder that is difficult to detect, particularly at an early age. PWS is caused by disruption of normal, epigenetically controlled gene function in the chromosome 15q11-q13 region. Clinical symptoms are difficult to diagnose in infants and only become clearer at later ages as the patients develop hyperphagia and morbid obesity. Molecular genetic tests are able to definitively diagnose PWS and allow early diagnosis of the syndrome. High resolution cytogenetic testing, methylation-specific PCR (MS-PCR), and linkage analysis are routinely used to diagnose PWS. To establish a linkage analysis method for Chinese patients, this study identified a useful set of STR markers in the typical PWS deletion and adjacent area, for linkage analysis in two Chinese families with PWS offspring. Using this method, the authors confn'rned that one patient had a paternal deletion in chromosome 15q 11-q 13 and the other patient had maternal uniparental heterodisomy of chromosome 15. MS -PCR and high resolution chromosome G-banding also confirmed this diagnosis. This linkage analysis method can detect both deletion and uniparental disomy, thus providing valuable information for genetic counseling and the opportunity to analyze the relationship between the genotype and phenotype of PWS. 展开更多
关键词 Prader-Willi Syndrome uniparental disomy OBESITY genomic imprinting linkage analysis
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GC/MS analyses of fractionated extraction of Shenfu coal with CS2,n-hexane,benzene 被引量:2
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作者 王晓华 魏贤勇 《Journal of Coal Science & Engineering(China)》 2008年第4期672-674,共3页
Shenfu coal was extracted with 0S2, n-hexane, benzene sequentially. The extracts were analyzed with GC/MS. It is presented that group seperation of soluble organic compounds in the coal can be achieved by fractionated... Shenfu coal was extracted with 0S2, n-hexane, benzene sequentially. The extracts were analyzed with GC/MS. It is presented that group seperation of soluble organic compounds in the coal can be achieved by fractionated extraction using different solvents. Main components in CS2 soluble fraction from Shenfu coal are alkyl-substituted arenes. Aliphatic hydrocarbons are overwhelmingly predominant in n-hexane-soluble fraction. Dito tricyclic aramatic hydrocarbons are identified in benzene-soluble fraction. The molecular structures detection of 2, 4, 6-trichlorobenzenamine and 3, 3', 4, 4', 5, 5'-hexachloro-1, 1'- biphenyl and 2-chlorocyclohexanol firstly provide information for existence form of chlorine in coal. 展开更多
关键词 solvent fractionated extraction chemical constituent GC/MS
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Proteomic analysis of the serum in patients with idiopathic pulmonary arterial hypertension 被引量:3
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作者 YU Min WANG Xing-xiang +4 位作者 ZHANG Fu-rong SHANG Yun-peng DU Yu-xi CHEN Hong-juan CHEN Jun-zhu 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第4期221-227,共7页
Idiopathic pulmonary arterial hypertension(IPAH) is a rare disease of unknown etiology.The exact pathogenesis of pulmonary arterial hypertension is still not well known.In the past decades,many protein molecules have ... Idiopathic pulmonary arterial hypertension(IPAH) is a rare disease of unknown etiology.The exact pathogenesis of pulmonary arterial hypertension is still not well known.In the past decades,many protein molecules have been found to be in-volved in the development of IPAH.With proteomic techniques,profiling of human plasma proteome becomes more feasible in searching for disease-related markers.In present study,we showed the protein expression profiles of the serum of IPAH and healthy controls after depleting a few high-abundant proteins in serum.Thirteen spots had changed significantly in IPAH com-pared with healthy controls and were identified by LC-MS/MS.Alpha-1-antitrypsin and vitronectin were down-regulated in IPAH and may be valuable candidates for further explorations of their roles in the development of IPAH. 展开更多
关键词 Idiopathic pulmonary arterial hypertension Two-dimensional gel electrophoresis LC-MS/MS
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SPEECH EMOTION RECOGNITION USING MODIFIED QUADRATIC DISCRIMINATION FUNCTION 被引量:9
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作者 Zhao Yan Zhao Li Zou Cairong Yu Yinhua 《Journal of Electronics(China)》 2008年第6期840-844,共5页
Quadratic Discrimination Function (QDF) is commonly used in speech emotion recognition, which proceeds on the premise that the input data is normal distribution. In this paper, we propose a transformation to normali... Quadratic Discrimination Function (QDF) is commonly used in speech emotion recognition, which proceeds on the premise that the input data is normal distribution. In this paper, we propose a transformation to normalize the emotional features, emotion recognition. Features based on prosody then derivate a Modified QDF (MQDF) to speech and voice quality are extracted and Principal Component Analysis Neural Network (PCANN) is used to reduce dimension of the feature vectors. The results show that voice quality features are effective supplement for recognition, and the method in this paper could improve the recognition ratio effectively. 展开更多
关键词 Speech emotion recognition Principal Component Analysis Neural Network (PCANN) Modified Quadratic Discrimination Function (MQDF)
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An MDL approach to efficiently discover communities in bipartite network 被引量:1
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作者 徐开阔 曾春秋 +2 位作者 元昌安 李川 唐常杰 《Journal of Central South University》 SCIE EI CAS 2014年第4期1353-1367,共15页
An minimum description length(MDL) criterion is proposed to choose a good partition for a bipartite network. A heuristic algorithm based on combination theory is presented to approach the optimal partition. As the heu... An minimum description length(MDL) criterion is proposed to choose a good partition for a bipartite network. A heuristic algorithm based on combination theory is presented to approach the optimal partition. As the heuristic algorithm automatically searches for the number of partitions, no user intervention is required. Finally, experiments are conducted on various datasets, and the results show that our method generates higher quality results than the state-of-art methods, cross-association and bipartite, recursively induced modules. Experiment results also show the good scalability of the proposed algorithm. The method is applied to traditional Chinese medicine(TCM) formula and Chinese herbal network whose community structure is not well known, and found that it detects significant and it is informative community division. 展开更多
关键词 community detection bipartite network minimum description length
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Support vector machine for prediction of meiotic recombination hotspots and coldspots in Saccharomyces cerevisiae
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作者 翁建洪 周童 +1 位作者 孙啸 陆祖宏 《Journal of Southeast University(English Edition)》 EI CAS 2006年第1期112-116,共5页
A novel method for predicting hotspots and coldspots using support vector machine (SVM) based on statistical learning theory is developed. This method is applied to published 303 hot and 48 cold open reading frames ... A novel method for predicting hotspots and coldspots using support vector machine (SVM) based on statistical learning theory is developed. This method is applied to published 303 hot and 48 cold open reading frames (ORFs) in Saccharomyces cerevisiae. The sequence features of general dinucleotide abundance and dinucleotide abundance based on codon usage are extracted, and then the data sets are classified with different parameters and kernel functions combined with the method of two-fold cross validation. The result indicates that 87.47% accuracy can be reached when classifying hot and cold ORF sequences with the kernel of radial basis function combined with dinucleotide abundance based on codon usage. 展开更多
关键词 meiotic recombination HOTSPOT coldspot dinucleotide abundance support vector machine
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Soil Organic Carbon and Its Fractions Across Vegetation Types:Effects of Soil Mineral Surface Area and Microaggregates 被引量:4
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作者 WU Qing-Biao WANG Xiao-Ke OUYANG Zhi-Yun 《Pedosphere》 SCIE CAS CSCD 2009年第2期258-264,共7页
Soil organic carbon(SOC)can act as a sink or source of atmospheric carbon dioxide;therefore,it is important to understand the amount and composition of SOC in terrestrial ecosystems,the spatial variation in SOC,and th... Soil organic carbon(SOC)can act as a sink or source of atmospheric carbon dioxide;therefore,it is important to understand the amount and composition of SOC in terrestrial ecosystems,the spatial variation in SOC,and the underlying mechanisms that stabilize SOC.In this study,density fractionation and acid hydrolysis were used to assess the spatial variation in SOC,the heavy fraction of organic carbon(HFOC),and the resistant organic carbon(ROC)in soils of the southern Hulun Buir region,northeastern China,and to identify the major factors that contribute to this variation.The results showed that as the contents of clay and silt particles(0–50μm)increased,both methylene blue(MB)adsorption by soil minerals and microaggregate contents increased in the 0–20 and 20–40 cm soil layers(P<0.05).Although varying with vegetation types,SOC,HFOC,and ROC contents increased significantly with the content of clay and silt particles, MB adsorption by soil minerals,and microaggregate content(P<0.05),suggesting that soil texture,the MB adsorption by soil minerals,and microaggregate abundance might be important factors influencing the spatial heterogeneity of carbon contents in soils of the southern Hulun Buir region. 展开更多
关键词 carbon fractions MICROAGGREGATES soil mineral surface area soil organic carbon VEGETATION
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The Smoothness of Weak Solutions to the System of Second Order Differential Equations with Non-negative Characteristics
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作者 张克农 《Chinese Quarterly Journal of Mathematics》 CSCD 1993年第4期15-22,共8页
In this paper,we will discuss smoothness of weak solutions for the system of second order differential equations eith non-negative characteristies.First of all,we establish boundary,and interior estimates and then we ... In this paper,we will discuss smoothness of weak solutions for the system of second order differential equations eith non-negative characteristies.First of all,we establish boundary,and interior estimates and then we prove that solutions of regularization problem satisfy Lipschitz condition. 展开更多
关键词 diff equa with non-negative characteristics regularization weak solution boundary and interior estimate
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Least squares weighted twin support vector machines with local information 被引量:1
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作者 花小朋 徐森 李先锋 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2638-2645,共8页
A least squares version of the recently proposed weighted twin support vector machine with local information(WLTSVM) for binary classification is formulated. This formulation leads to an extremely simple and fast algo... A least squares version of the recently proposed weighted twin support vector machine with local information(WLTSVM) for binary classification is formulated. This formulation leads to an extremely simple and fast algorithm, called least squares weighted twin support vector machine with local information(LSWLTSVM), for generating binary classifiers based on two non-parallel hyperplanes. Two modified primal problems of WLTSVM are attempted to solve, instead of two dual problems usually solved. The solution of the two modified problems reduces to solving just two systems of linear equations as opposed to solving two quadratic programming problems along with two systems of linear equations in WLTSVM. Moreover, two extra modifications were proposed in LSWLTSVM to improve the generalization capability. One is that a hot kernel function, not the simple-minded definition in WLTSVM, is used to define the weight matrix of adjacency graph, which ensures that the underlying similarity information between any pair of data points in the same class can be fully reflected. The other is that the weight for each point in the contrary class is considered in constructing equality constraints, which makes LSWLTSVM less sensitive to noise points than WLTSVM. Experimental results indicate that LSWLTSVM has comparable classification accuracy to that of WLTSVM but with remarkably less computational time. 展开更多
关键词 least squares similarity information hot kernel function noise points
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应用经验模式分解和随机数据重排的微弱信号感知
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作者 Arnab Roy John F.Doherty +1 位作者 郑仕链 景振海 《通信对抗》 2012年第1期57-61,共5页
给出了一种利用经验模式分解(Empirical Mode Decomposition,EMD)感知微弱信号的技术,对于噪声占支配地位的信号,这种技术具有和二分滤波器组类似的性质。EMD分解将宽带噪声分解为一系列固有模式,以对数尺度衡量,这些模式的平均能量... 给出了一种利用经验模式分解(Empirical Mode Decomposition,EMD)感知微弱信号的技术,对于噪声占支配地位的信号,这种技术具有和二分滤波器组类似的性质。EMD分解将宽带噪声分解为一系列固有模式,以对数尺度衡量,这些模式的平均能量随平均频率线性递减,而某些模式的能量则包含了信号特征。因为微弱随机信号对特定模式(对应于信号频率成分的模式)的能量有贡献,所以这些模式可以用来检测信号的存在性。通过对原始数据样点进行局部随机重排,能够进一步提高EMD技术的有效性。原因在于重排可以产生新的随机噪声信号实现,而该信号的EMD分解和原信号分解的差异可以忽略。通过多次重排,将非线性分解得到的信号模式进行平均可以提高信号检测的可靠性。本文主要讨论了这种新EMD检测流程的应用,并比较了该技术与多种标准信号检测技术的性能。 展开更多
关键词 经验模式分解 微弱信号检测 随机数据重排 二分滤波器
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1~H NMR-based serum metabolic profiling in compensatedand decompensated cirrhosis 被引量:10
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作者 Su-Wen Qi Zhi-Guang Tu +4 位作者 Wu-Jian Peng Lin-Xian Wang Xin Ou-Yang An-Ji Cai Yong Dai 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第3期285-290,共6页
AIM: To study the metabolic profiling of serum samples from compensated and decompensated cirrhosis patients. METHODS: A pilot metabolic profiling study was conducted using three groups: compensated cirrhosis patients... AIM: To study the metabolic profiling of serum samples from compensated and decompensated cirrhosis patients. METHODS: A pilot metabolic profiling study was conducted using three groups: compensated cirrhosis patients (n = 30), decompensated cirrhosis patients (n = 30) and healthy controls (n = 30). A 1H nuclear magnetic resonance (NMR)-based metabonomics approach was used to obtain the serum metabolic profiles of the samples. The acquired data were processed by multivariate principal component analysis and orthogonal partial least-squares discriminant analysis (OPLS-DA). RESULTS: The OPLS-DA model was capable of distinguishing between decompensated and compensated cirrhosis patients, with an R2Y of 0.784 and a Q2Y of 0.598. Twelve metabolites, such as pyruvate, phenylala-nine and succinate, were identified as the most influential factors for the difference between the two groups. The validation of the diagnosis prediction showed that the accuracy of the OPLS-DA model was 85% (17/20). CONCLUSION: 1H NMR spectra combined with pattern recognition analysis techniques offer a new way to diagnose compensated and decompensated cirrhosis in the future. 展开更多
关键词 Liver cirrhosis Metabolic profiling Orthogo- nal partial least-squares discriminant analysis
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Chromatographic separation of Be(Ⅱ) from Mg(Ⅱ), Ca(Ⅱ), Sr(Ⅱ) and Ba(Ⅱ) using poly[dibenzo-18-crown-6] and L-arginine
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作者 Sandip R. Sabale Baburao S. Mohite 《Journal of Chemistry and Chemical Engineering》 2009年第6期37-43,共7页
A simple and selective method for the separation of Be(Ⅱ) was developed using poly[dibenzo-18-crown-6] as a stationary phase in column chromatography. The study was carried out in L-arginine medium. 1.0-8.0 M HCl a... A simple and selective method for the separation of Be(Ⅱ) was developed using poly[dibenzo-18-crown-6] as a stationary phase in column chromatography. The study was carried out in L-arginine medium. 1.0-8.0 M HCl and CH3COOH, 0.5-8.0 M HBr, HClO4 and H2SO4, 0.2-1.0 M EDTA and 0.02-0.12 M ammonium oxalate were found to be an efficient eluents for Be(Ⅱ). The capacity of polymer was 0.554-0.01 mmol/g of crown polymer. The tolerance limit of various cations and anions were reported. Be(Ⅱ) was quantitatively separated from Mg(Ⅱ), Ca(Ⅱ), Sr(Ⅱ) and Ba(Ⅱ). The selective separation of Be(Ⅱ) was possible from multicomponent mixtures. The method was extended to determine Be(Ⅱ) from geological samples. Method was simple, rapid and selective having good reproducibility (approximately4-2%). 展开更多
关键词 Be(Ⅱ) poly[dibenzo-18-crown-6] L-ARGININE SEPARATION column chromatography
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The Applicability of the Density Rule of Pathwardhan and Kumer and the Rule Based on Linear Isopiestic Relation 被引量:1
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作者 胡玉峰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第3期319-321,共3页
The applicability of the density rule of Pathwardhan and Kumer and the rule based on the linear isopiestic relation is studied by comparison with experimental density data in the literature. Predicted and measured val... The applicability of the density rule of Pathwardhan and Kumer and the rule based on the linear isopiestic relation is studied by comparison with experimental density data in the literature. Predicted and measured values for 18 electrolyte mixtures are compared. The two rules are good for mixtures with and without common ions, including those containing associating ions. The deviations of the rule based on the linear isopiestic relation are slightly higher for the mixtures involving very strong ion complexes, but the predictions are still quite satisfactory.The density rule of Pathwardhan and Kumer is more accurate for these mixtures. However, it is not applicable for mixtures containing non-electrolytes. The rule based on the linear isopiestic relation is extended to mixtures involving non-electrolytes. The predictions for the mixtures containing both electrolytes and non-electrolytes and the non-electrolyte mixtures are accurate. All these results indicate that this rule is a widely applicable approach. 展开更多
关键词 binary density rules DENSITY apparent molar volume multicomponent system binary sub-system
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Carbon dioxide insufflation during colonoscopy in deeply sedated patients 被引量:4
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作者 Rajvinder Singh Eu Nice Neo +8 位作者 Nazree Nordeen Ganesananthan Shanmuganathan Angelie Ashby Sharon Drummond Garry Nind Elizabeth Murphy Andrew Luck Graeme Tucker William Tam 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第25期3250-3253,共4页
AIM:To compare the impact of carbon dioxide(CO2) and air insufflation on patient tolerance/safety in deeply sedated patients undergoing colonoscopy.METHODS:Patients referred for colonoscopy were randomized to receive ... AIM:To compare the impact of carbon dioxide(CO2) and air insufflation on patient tolerance/safety in deeply sedated patients undergoing colonoscopy.METHODS:Patients referred for colonoscopy were randomized to receive either CO2 or air insufflation during the procedure.Both the colonoscopist and patient were blinded to the type of gas used.During the procedure,insertion and withdrawal times,caecal intubationrates,total sedation given and capnography readings were recorded.The level of sedation and magnitude of patient discomfort during the procedure was assessed by a nurse using a visual analogue scale(VAS)(0-3).Patients then graded their level of discomfort and abdominal bloating using a similar VAS.Complications during and after the procedure were recorded.RESULTS:A total of 142 patients were randomized with 72 in the air arm and 70 in the CO2 arm.Mean age between the two study groups were similar.Insertion time to the caecum was quicker in the CO2 group at 7.3 min vs 9.9 min with air(P = 0.0083).The average withdrawal times were not significantly different between the two groups.Caecal intubation rates were 94.4% and 100% in the air and CO2 groups respectively(P = 0.012).The level of discomfort assessed by the nurse was 0.69(air) and 0.39(CO2)(P = 0.0155) and by the patient 0.82(air) and 0.46(CO2)(P = 0.0228).The level of abdominal bloating was 0.97(air) and 0.36(CO2)(P = 0.001).Capnography readings trended to be higher in the CO2 group at the commencement,caecal intubation,and conclusion of the procedure,even though this was not significantly different when compared to readings obtained during air insufflation.There were no complications in both arms.CONCLUSION:CO2 insufflation during colonoscopy is more efficacious than air,allowing quicker and better cecal intubation rates.Abdominal discomfort and bloating were significantly less with CO2 insufflation. 展开更多
关键词 COLONOSCOPY Carbon dioxide Air Insuffla-tions Patient tolerance Safety Efficacy
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Simulation of gas-solid fluidized bed reactor for F-T synthesis 被引量:1
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作者 CAI Jin LI Tao +2 位作者 SUN Qi-wen YING Wei-yong FANG Ding-ye 《Journal of Coal Science & Engineering(China)》 2009年第4期420-425,共6页
Using the lumping method, CH_4, C_3H_8, C_10H_22, and C_22H_44 were chosen as themodel products, and CO as the key component. The mathematical model of a gas-solidfluidized bed reactor was established based on some hy... Using the lumping method, CH_4, C_3H_8, C_10H_22, and C_22H_44 were chosen as themodel products, and CO as the key component. The mathematical model of a gas-solidfluidized bed reactor was established based on some hypotheses. The consumption kinetic model of CO was investigated, and the parameters were estimated by UniversalGlobal Optimization with the Marquardt method. Residual error distribution and a statisticaltest show that the intrinsic kinetic models are reliable and acceptable. A model of carbonchain growth probability was established in terms of experiments. Coupled with the Ander-son- Schulz-Flory (ASF) distribution, the amount of specific product could be obtained.Large- scale cold model experiments were conducted to investigate the distribution of thegas (solid) phase and determine the function of the voidage with the location of the catalytic bed. The change tendencies of the components in the catalytic bed at different temperatures were computed and figured out. The calculated value computed by the modelestablished for the Fe-based F-T synthesis catalyst fit the experimental value very wellunder the same operating conditions, and all the absolute values of the relative deviationsare less than 5%. 展开更多
关键词 gas-solid fluidized bed F-T synthesis REACTOR LUMPING
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