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Anti-hyperglycemic effect of the polysaccharide fraction isolated from mactra veneriformis

Lingchong WANG, Hao WU, Nian CHANG, Kun ZHANG

《化学科学与工程前沿(英文)》 2011年 第5卷 第2期   页码 238-244 doi: 10.1007/s11705-010-0002-2

摘要: Total macromolecule extract was obtained from the soft body of by the coupling techniques of decoction and alcohol precipitation. The extract was deproteinized with an ion exchange column, and resulted in the purifying of the crude polysaccharide fraction. It was found by chemical analysis that the crude polysaccharide part is composed of abundant polysaccharides (>95%) and few proteins (<1%). Furthermore, only one type of monosaccharide, glucose, was detected from its hydrolytes by thin-layer chromatography, indicating that the polysaccharides might be analogs of glucosan. The anti-hyperglycemia effects of the crude polysaccharide part were preliminarily investigated using several pharmacological methods in normal and diabetic mice. Animal experimental results showed that the crude polysaccharide fraction exhibited proper glycemia inhibition activity, and 300 mg/kg-weight dose has the optimal effect among all the studied doses. It is concluded that the crude polysaccharide fraction can be explored as a novel health product that possesses potential as an anti-hyperglycemic agent.

关键词: anti-hyperglycemia     Mactra veneriformis     polysaccharide     monosaccharide composition     oral glucose tolerance test    

FMO3--TMAO axis modulates the clinical outcome in chronic heart-failure patients with reduced ejection fraction

《医学前沿(英文)》 2022年 第16卷 第2期   页码 295-305 doi: 10.1007/s11684-021-0857-2

摘要: The association among plasma trimethylamine-N-oxide (TMAO), FMO3 polymorphisms, and chronic heart failure (CHF) remains to be elucidated. TMAO is a microbiota-dependent metabolite from dietary choline and carnitine. A prospective study was performed including 955 consecutively diagnosed CHF patients with reduced ejection fraction, with the longest follow-up of 7 years. The concentrations of plasma TMAO and its precursors, namely, choline and carnitine, were determined by liquid chromatography-mass spectrometry, and the FMO3 E158K polymorphisms (rs2266782) were genotyped. The top tertile of plasma TMAO was associated with a significant increment in hazard ratio (HR) for the composite outcome of cardiovascular death or heart transplantation (HR=1.47, 95% CI=1.13–1.91, P=0.004) compared with the lowest tertile. After adjustments of the potential confounders, higher TMAO could still be used to predict the risk of the primary endpoint (adjusted HR=1.33, 95% CI=1.01–1.74, P=0.039). This result was also obtained after further adjustment for carnitine (adjusted HR=1.33, 95% CI=1.01–1.74, P=0.039). The FMO3 rs2266782 polymorphism was associated with the plasma TMAO concentrations in our cohort, and lower TMAO levels were found in the AA-genotype. Thus, higher plasma TMAO levels indicated increased risk of the composite outcome of cardiovascular death or heart transplantation independent of potential confounders, and the FMO3 AA-genotype in rs2266782 was related to lower plasma TMAO levels.

关键词: chronic heart failure     trimethylamine-N-oxide     flavin monooxygenase 3     single nucleotide polymorphism    

Effect of ignition timing and hydrogen fraction on combustion and emission characteristics of natural

WANG Jinhua, HUANG Zuohua, LIU Bing, ZENG Ke, YU Jinrong, JIANG Deming

《能源前沿(英文)》 2008年 第2卷 第2期   页码 194-201 doi: 10.1007/s11708-008-0035-0

摘要: An experimental study on the combustion and emission characteristics of a direct-injection spark-ignited engine fueled with natural gas/hydrogen blends under various ignition timings was conducted. The results show that ignition timing has a significant influence on engine performance, combustion and emissions. The interval between the end of fuel injection and ignition timing is a very important parameter for direct-injection natural gas engines. The turbulent flow in the combustion chamber generated by the fuel jet remains high and relative strong mixture stratification is introduced when decreasing the angle interval between the end of fuel injection and ignition timing giving fast burning rates and high thermal efficiencies. The maximum cylinder gas pressure, maximum mean gas temperature, maximum rate of pressure rise and maximum heat release rate increase with the advancing of ignition timing. However, these parameters do not vary much with hydrogen addition under specific ignition timing indicating that a small hydrogen fraction addition of less than 20% in the present experiment has little influence on combustion parameters under specific ignition timing. The exhaust HC emission decreases while the exhaust CO concentration increases with the advancing of ignition timing. In the lean combustion condition, the exhaust CO does not vary much with ignition timing. At the same ignition timing, the exhaust HC decreases with hydrogen addition while the exhaust CO and CO do not vary much with hydrogen addition. The exhaust NO increases with the advancing of ignition timing and the behavior tends to be more obvious at large ignition advance angle. The brake mean effective pressure and the effective thermal efficiency of natural gas/hydrogen mixture combustion increase compared with those of natural gas combustion when the hydrogen fraction is over 10%.

Utilization of nano/micro-size iron recovered from the fine fraction of automobile shredder residue for

Jiwan SINGH, Yoon-Young CHANG, Jae-Kyu YANG, Seon-Hong KANG, Janardhan Reddy KODURU

《环境科学与工程前沿(英文)》 2016年 第10卷 第4期 doi: 10.1007/s11783-016-0848-8

摘要: Phenol removal by n/m Fe in the presence of H O was highly effective. Increasing the amounts of n/m Fe and H O ?increased the phenol removal rate. Phenol removal was decreased with an increase in the concentration of phenol. The natural pH (6.9) of the solution was highly effective for phenol removal. The pseudo-first-order kinetics was best fitted for the degradation of phenol. The study investigates the magnetic separation of Fe from automobile shredder residue (ASR) (<0.25 mm) and its application for phenol degradation in water. The magnetically separated Fe was subjected to an ultrasonically assisted acid treatment, and the degradation of phenol in an aqueous solution using nano/micro-size Fe (n/m Fe) was investigated in an effort to evaluate the possibility of utilizing n/m Fe to remove phenol from wastewater. The prepared n/m Fe was analyzed by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The effects of the dosages of n/mFe, pH, concentration of phenol and amount of H O on phenol removal were evaluated. The results confirm that the phenol degradation rate was improved with an increase in the dosages of n/mFe and H O ; however, the rate is reduced when the phenol concentration is higher. The degradation of phenol by n/mFe followed the pseudo-first-order kinetics. The value of the reaction rate constant ( was increased as the amounts of n/m Fe and H O increased. Conversely, the value of was reduced when the concentration of phenol was increased. The probable mechanism behind the degradation of phenol by n/m Fe is the oxidation of phenol through hydroxyl radicals which are produced during the reaction between H O and n/m Fe.

关键词: Automobile shredder residue (ASR)     Fe     Phenol     Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR)     Mechanism    

Emission characteristics of a turbocharged diesel engine fueled with gas-to-liquids

WU Tao, ZHANG Wugao, FANG Junhua, HUANG Zhen

《能源前沿(英文)》 2007年 第1卷 第3期   页码 331-335 doi: 10.1007/s11708-007-0049-z

摘要: Emission characteristics of a turbocharged, inter-cooled, heavy-duty diesel engine operating on neat gas-to-liquids (GTL) and blends of GTL with conventional diesel were investigated and a comparison was made with those of diesel fuel. The results show that nitrogen oxides (NO), smoke, and particulate matter (PM) emissions can be decreased when operating on GTL and diesel-GTL blends. Engine emissions decrease with an increase of GTL fraction in the blends. Compared with diesel fuel, an engine operating on GTL can reduce NO, PM, carbon monoxide (CO), and hydrocarbon (HC) by 23.7%, 27.6%, 16.6% and 12.9% in ECE R49 13-mode procedure, respectively. Engine speed and load have great influences on emissions when operating on diesel-GTL blends and diesel fuel in the turbocharged diesel engine. The study indicates that GTL is a promising alternative fuel for diesel engines to reduce emissions.

关键词: comparison     conventional     fraction     13-mode procedure     study    

A method of determining flame radiation fraction induced by interaction burning of tri-symmetric propane

Jie JI, Junrui DUAN, Huaxian WAN

《能源前沿(英文)》 2022年 第16卷 第6期   页码 1017-1026 doi: 10.1007/s11708-020-0716-x

摘要: The interaction of multiple fires may lead to a higher flame height and more intense radiation flux than a single fire, which increases the possibility of flame spread and risks to the surroundings. Experiments were conducted using three burners with identical heat release rates (HRRs) and propane as the fuel at various spacings. The results show that flames change from non-merging to merging as the spacing decreases, which result in a complex evolution of flame height and merging point height. To facilitate the analysis, a novel merging criterion based on the dimensionless spacing / was proposed. For non-merging flames ( / >0.368), the flame height is almost identical to a single fire; for merging flames ( / ≤0.368), based on the relationship between thermal buoyancy and thrust (the pressure difference between the inside and outside of the flame), a quantitative analysis of the flame height, merging point height, and air entrainment was formed, and the calculated merging flame heights show a good agreement with the measured experimental values. Moreover, the multi-point source model was further improved, and radiation fraction of propane was calculated. The data obtained in this study would play an important role in calculating the external radiation of propane fire.

关键词: flame interaction     air entrainment     flame height     multi-point source model     thermal radiation    

Temporal echocardiography findings in patients with fulminant myocarditis: beyond ejection fraction decline

Houjuan Zuo, Rui Li, Fei Ma, Jiangang Jiang, Kun Miao, Haojie Li, Eike Nagel, Marijana Tadic, Hong Wang, Dao Wen Wang

《医学前沿(英文)》 2020年 第14卷 第3期   页码 284-292 doi: 10.1007/s11684-019-0713-9

摘要: The features of myocardial strains from speckle-tracking echocardiography (STE) have not been well defined in fulminant myocarditis (FM) patients. In this study, changes in the left ventricular ejection fraction (LVEF) and global and layer-specific myocardial strains over time were monitored. We aimed to determine the echocardiographic patterns of FM and ascertain their significance in FM treatment. Twenty patients who were clinically diagnosed with FM and received mechanical life support were prospectively enrolled. Conventional echocardiographic measurements were obtained, and serial strain echocardiography was performed from admission to hospital discharge until LVEF recovery (>50%). Global/regional peak systolic longitudinal strains (GLS/RLS) and layer-specific longitudinal strains were quantified, and their changes with time were monitored in 14 FM patients. All patients had severely impaired cardiac function. Steep improvement in LVEF and GLS were observed within 6 days. Layer-specific strain analysis showed that reduction at admission or recovery at discharge in the endocardium and epicardium strains were equal. In conclusion, FM patients who received mechanical circulatory supports exhibited steep improvement in ventricular function within 6 days. The patchy and diffused distribution pattern of reduced RLS and equally and severely impaired strain in the endocardium and epicardium are valuable features in the diagnosis of FM.

关键词: fulminant myocarditis     acute myocarditis     2D speckle tracking echocardiography     left ventricular function     global longitudinal strain    

Chemical identification and genotoxicity analysis of petrochemical industrial wastewater

Jing ZHANG, Shigong WANG, Can WANG, Hongying HU

《环境科学与工程前沿(英文)》 2012年 第6卷 第3期   页码 350-359 doi: 10.1007/s11783-012-0404-0

摘要: The actual harmful effects of industrial wastewater can not be reflected by the conventional water quality index. Therefore, the change in dissolved organic matter and the genetic toxicity of petrochemical wastewater were observed in the current study by examining the wastewater treatment plant of a large petrochemical enterprise in Northwest China. Using XAD-8, MSC, and DA-7 resins, the wastewater was separated into six fractions, namely, hydrophobic acid (HOA), hydrophobic neutral (HOB), hydrophobic alkaline, hydrophilic acid, hydrophilic alkaline, and hydrophilic neutral. Umu-test was used to detect the genetic toxicity of the wastewater samples, and fluorescence spectra were also obtained to examine genetic toxic substances. The results show that wastewater treatment facilities can effectively reduce the concentration of organic matter in petrochemical wastewater ( <0.05). However, the mixing of aniline wastewater can increase the amount of organic carbon ( <0.05) and can overload facilities. This finding shows that the mixed collection and joint treatment of different types of petrochemical wastewater can affect the water quality of the effluent. Particularly, hydrophobic substances can be difficult to remove and account for a relatively large proportion of the effluent. The mixture of aniline wastewater can increase the genetic toxicity of the effluent ( <0.05), and biologic treatment can not effectively decrease the toxicity. Most of the genetic toxicology may exist in the HOA and HOB fractions. Fluorescence spectroscopy also confirms this result, and tryptophan-like substances may play an important role in genetic toxicity.

关键词: dissolved organic matter     resin fraction     genetic toxicity     fluorescence excitation and emission matrix    

The cavitation erosion damage process of dynamically loaded journal bearings

MA Yan-yan, CHENG Xian-hua

《机械工程前沿(英文)》 2006年 第1卷 第4期   页码 461-464 doi: 10.1007/s11465-006-0059-2

摘要: The cavitation damage model was built using finite element analysis software MSC.Marc. This paper attempted to numerically analyze the action process based on damage mechanics when a jet created by bubble collapse acted on the bearing surface in the process of cavitation erosion. The numerical results show that the values of equivalent plastic strain and void volume fraction increase with time. The values of damage scalar are higher on the bearing surface and subsurface, and decrease when it approaches the interface of overlay and nickel layer. The strain history and damage evolvement of bearing material acted on by jet impact load can be calculated efficiently using the proposed method, which develops a new method of analyzing cavitation erosion failure of the bearing surface.

关键词: bearing     fraction increase     collapse     process     evolvement    

Experimental and parametrical investigation of pre-stressed ultrahigh-performance fiber-reinforced concrete railway sleepers

《结构与土木工程前沿(英文)》 2023年 第17卷 第3期   页码 411-428 doi: 10.1007/s11709-023-0928-3

摘要: In this study, ultrahigh-performance fiber-reinforced concrete (UHPFRC) used in a type B70 concrete sleeper is investigated experimentally and parametrically. The main parameters investigated are the steel fiber volume fractions (0%, 0.5%, 1%, and 1.5%). Under European standards, 35 UHPFRC sleepers are subjected to static bending tests at the center and rail seat sections, and the screw on the fastening system is pulled out. The first cracking load, failure load, failure mode, crack propagation, load–deflection curve, load–crack width, and failure load from these tests are measured and compared with those of a control sleeper manufactured using normal concrete C50. The accuracy of the parametric study is verified experimentally. Subsequently, the results of the study are applied to UHPFRC sleepers with different concrete volumes to investigate the effects of the properties of UHPFRC on their performance. Experimental and parametric study results show that the behavior of UHPFRC sleepers improves significantly when the amount of steel fiber in the mix is increased. Sleepers manufactured using UHPFRC with a steel fiber volume fraction of 1% and a concrete volume less than 25% that of standard sleeper B70 can be used under the same loads and requirements, which contributes positively to the cost and surrounding environment.

关键词: pre-stressed concrete sleeper     ultrahigh performance fiber-reinforced concrete     pull-out test     static bending test     steel fiber     aspect ratio     volume fraction    

Feasibility of bubble surface modification for natural organic matter removal from river water using dissolved air flotation

Yulong Shi, Jiaxuan Yang, Jun Ma, Congwei Luo

《环境科学与工程前沿(英文)》 2017年 第11卷 第6期 doi: 10.1007/s11783-017-0954-2

摘要: A novel, functionalized bubble surface can be obtained in dissolved air flotation (DAF) by dosing chemicals in the saturator. In this study, different cationic chemicals were used as bubble surface modifiers, and their effects on natural organic matter (NOM) removal from river water were investigated. NOM in the samples was fractionated based on molecular weight and hydrophobicity. The disinfection byproduct formation potentials of each fraction and their removal efficiencies were also evaluated. The results showed that chitosan was the most promising bubble modifier compared with a surfactant and a synthetic polymer. Tiny bubbles in the DAF pump system facilitated the adsorption of chitosan onto microbubble surfaces. The hydrophobic NOM fraction was preferentially removed by chitosan-modified bubbles. Decreasing the recycle water pH from 7.0 to 5.5 improved the removal of hydrophilic NOM with low molecular weight. Likewise, hydrophilic organic compounds gave high dihaloacetic acid yields in raw water. An enhanced reduction of haloacetic acid precursors was obtained with recycle water at pH values of 5.5 and 4.0. The experimental results indicate that NOM fractions may interact with bubbles through different mechanisms. Positive bubble modification provides an alternative approach for DAF to enhance NOM removal.

关键词: Bubble surface modification     Chitosan     Disinfection by-product     Dissolved air flotation     Organic fraction    

Fuel poverty and low carbon emissions: a comparative study of the feasibility of the hybrid renewable energy systems incorporating combined heat and power technology

《能源前沿(英文)》 2022年 第16卷 第2期   页码 336-356 doi: 10.1007/s11708-021-0748-x

摘要: Fuel poverty is most prevalent in North East England with 14.4% of fuel poor households in Newcastle upon Tyne. The aim of this paper was to identify a grid connected renewable energy system coupled with natural gas reciprocating combined heat and power unit, that is cost-effective and technically feasible with a potential to generate a profit from selling energy excess to the grid to help alleviate fuel poverty. The system was also aimed at low carbon emissions. Fourteen models were designed and optimized with the aid of the HOMER Pro software. Models were compared with respect to their economic, technical, and environmental performance. A solution was proposed where restrictions were placed on the size of renewable energy components. This configuration consists of 150 kW CHP, 300 kW PV cells, and 30 kW wind turbines. The renewable fraction is 5.10% and the system yields a carbon saving of 7.9% in comparison with conventional systems. The initial capital investment is $1.24 million which enables the system to have grid sales of 582689 kWh/a. A conservative calculation determined that 40% of the sales can be used to reduce the energy cost of fuel poor households by $706 per annum. This solution has the potential to eliminate fuel poverty at the site analyzed.

关键词: greenhouse gas control     low carbon target     grid connected     renewable fraction     fuel poverty     combined heat and power     HOMER Pro    

空调房间的空气品质及其控制研究

邹声华,李强,于梅春,杨景华

《中国工程科学》 2007年 第9卷 第3期   页码 82-86

摘要:

以典型的空调房间为例,分析了新风和回风对室内空气品质的影响。研究表明室内污染源的不断增加 是室内空气品质恶化的主要原因,新风的质量直接影响室内空气品质,回风是室内空气的二次污染源。导出了新 风和回风对室内空气污染的理论计算公式,通过仿真表明:基于室内空气中典型的有害气体体积分数(以CO2为 代表)的变化来控制新风量,是非常有效的。

关键词: 室内空气品质     污染物体积分数     新风量     控制     仿真    

Experimental studies of ash film fractions based on measurement of cenospheres geometry in pulverized coal combustion

Siqi LIU, Yanqing NIU, Liping WEN, Yang LIANG, Bokang YAN, Denghui WANG, Shi’en HUI

《能源前沿(英文)》 2021年 第15卷 第1期   页码 91-98 doi: 10.1007/s11708-020-0806-9

摘要: In pulverized coal particle combustion, part of the ash forms the ash film and exerts an inhibitory influence on combustion by impeding the diffusion of oxygen to the encapsulated char core, while part of the ash diffuses toward the char core. Despite the considerable ash effects on combustion, the fraction of ash film still remains unclear. However, the research of the properties of cenospheres can be an appropriate choice for the fraction determination, being aware that the formation of cenospheres is based on the model of coal particles with the visco-plastic ash film and a solid core. The fraction of ash film is the ratio of the measuring mass of ash film and the total ash in coal particle. In this paper, the Huangling bituminous coal with different sizes was burnt in a drop-tube furnace at 1273, 1473, and 1673 K with air as oxidizer. A scanning electron microscope (SEM) and cross-section analysis have been used to study the geometry of the collected cenospheres and the effects of combustion parameters on the fraction of ash film. The results show that the ash film fraction increases with increasing temperature and carbon conversion ratio but decreases with larger sizes of coal particles. The high fraction of ash film provides a reasonable explanation for the extinction event at the late burnout stage. The varied values of ash film fractions under different conditions during the dynamic combustion process are necessary for further development of kinetic models.

关键词: ash film fraction     cenospheres     coal combustion     fly ash    

分群结构对IHNI-1堆动态参数计算结果的影响研究

张良,赵柱民,江新标,陈伟,周永茂

《中国工程科学》 2012年 第14卷 第8期   页码 47-50

摘要:

基于WIMS和CITATION程序的计算结果,编制了动态参数计算程序CKPWC(calculating kinetic parameters based on WIMS and CITATION),对医院中子照射器I型堆(in hospital neutron irradiator mark 1 reactor,IHNI-1)的动态参数计算进行了研究。首先使用WIMS计算出均匀化栅元截面以及69群通量,再使用CITATION进行四群扩散计算,最后编制动态参数计算程序,计算了IHNI-1动态参数(缓发中子有效份βeff和中子代时间Λ)。经过比较研究发现,分群结构对动态参数的计算结果有很大的影响。给出了计算IHNI-1缓发中子份额和中子代时间的最佳四群分群结构。使用文章中的最佳分群结构思想对西安脉冲堆动态参数进行了验证计算,计算结果与设计值符合一致,说明给出的IHNI-1动态参数计算结果具有一定的可信性。

关键词: 医院中子照射器I型堆     动态参数     缓发中子有效份额     中子代时间    

标题 作者 时间 类型 操作

Anti-hyperglycemic effect of the polysaccharide fraction isolated from mactra veneriformis

Lingchong WANG, Hao WU, Nian CHANG, Kun ZHANG

期刊论文

FMO3--TMAO axis modulates the clinical outcome in chronic heart-failure patients with reduced ejection fraction

期刊论文

Effect of ignition timing and hydrogen fraction on combustion and emission characteristics of natural

WANG Jinhua, HUANG Zuohua, LIU Bing, ZENG Ke, YU Jinrong, JIANG Deming

期刊论文

Utilization of nano/micro-size iron recovered from the fine fraction of automobile shredder residue for

Jiwan SINGH, Yoon-Young CHANG, Jae-Kyu YANG, Seon-Hong KANG, Janardhan Reddy KODURU

期刊论文

Emission characteristics of a turbocharged diesel engine fueled with gas-to-liquids

WU Tao, ZHANG Wugao, FANG Junhua, HUANG Zhen

期刊论文

A method of determining flame radiation fraction induced by interaction burning of tri-symmetric propane

Jie JI, Junrui DUAN, Huaxian WAN

期刊论文

Temporal echocardiography findings in patients with fulminant myocarditis: beyond ejection fraction decline

Houjuan Zuo, Rui Li, Fei Ma, Jiangang Jiang, Kun Miao, Haojie Li, Eike Nagel, Marijana Tadic, Hong Wang, Dao Wen Wang

期刊论文

Chemical identification and genotoxicity analysis of petrochemical industrial wastewater

Jing ZHANG, Shigong WANG, Can WANG, Hongying HU

期刊论文

The cavitation erosion damage process of dynamically loaded journal bearings

MA Yan-yan, CHENG Xian-hua

期刊论文

Experimental and parametrical investigation of pre-stressed ultrahigh-performance fiber-reinforced concrete railway sleepers

期刊论文

Feasibility of bubble surface modification for natural organic matter removal from river water using dissolved air flotation

Yulong Shi, Jiaxuan Yang, Jun Ma, Congwei Luo

期刊论文

Fuel poverty and low carbon emissions: a comparative study of the feasibility of the hybrid renewable energy systems incorporating combined heat and power technology

期刊论文

空调房间的空气品质及其控制研究

邹声华,李强,于梅春,杨景华

期刊论文

Experimental studies of ash film fractions based on measurement of cenospheres geometry in pulverized coal combustion

Siqi LIU, Yanqing NIU, Liping WEN, Yang LIANG, Bokang YAN, Denghui WANG, Shi’en HUI

期刊论文

分群结构对IHNI-1堆动态参数计算结果的影响研究

张良,赵柱民,江新标,陈伟,周永茂

期刊论文