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Interferon-gamma release assays as a tool for differential diagnosis of gastrointestinal tuberculosis
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作者 Tsvetelina Velikova Anita Aleksandrova 《World Journal of Clinical Cases》 SCIE 2024年第27期6015-6019,共5页
In this editorial,we comment on an article published in a recent issue of the World Journal of Clinical Cases.There is a pressing need for reliable tools for diagnosing tuberculosis(TB)of the gastrointestinal tract.De... In this editorial,we comment on an article published in a recent issue of the World Journal of Clinical Cases.There is a pressing need for reliable tools for diagnosing tuberculosis(TB)of the gastrointestinal tract.Despite advancements in the diagnosis and treatment,TB remains a global health challenge.Ali et al demon-strated that TB may mimic gastrointestinal conditions,such as gastric outlet obstruction,causing a delay in the diagnosis.Furthermore,the latter complication is frequently observed during infections,including Helicobacter pylori,and rarely is related to TB,as in the presented case.In line with this,we think that laboratory tests based on interferon-gamma release assays can be a helpful tool for diagnosing latent TB paced in the gastrointestinal tract.Innovative strategies and approaches for diagnosing latent/active extra pulmonary TB are crucial for establishing the diagnosis early and enhancing treatment strategies to mitigate the global burden of TB. 展开更多
关键词 TUBERCULOSIS Gastrointestinal tuberculosis interferon-gamma release assay IGRA Primary gastroduodenal tuberculosis Gastric outlet obstruction Case report
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Study on the Rapid Method to Predict Longevity of Controlled Release Fertilizer Coated by Water Soluble Resin 被引量:10
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作者 DAI Jian-jun FAN Xiao-lin +2 位作者 YU Jian-gang LIU Fang ZHANG Qiao 《Agricultural Sciences in China》 CAS CSCD 2008年第9期1127-1132,共6页
The study discussed the rapid method to test and predict the longevity of controlled release fertilizers (CRFs) coated by water soluble resin by using the short-term leaching under higher temperature. Pure water dis... The study discussed the rapid method to test and predict the longevity of controlled release fertilizers (CRFs) coated by water soluble resin by using the short-term leaching under higher temperature. Pure water dissolving incubation and higher temperature leaching were used to study the patterns of the nutrient release of the CRFs. The correlation analysis between the days at 25℃ and the hours at 80℃ of Trincote 1 and Trincote 2 for the same cumulative release rates were conducted. Patterns of cumulative nutrient release curve followed one factor quadratic regression equation at each given temperatures, and each of relative coefficient was bigger than 0.995. As the temperature increased, nutrients release of the CRFs increased. The longevity of resin coated CRFs were predicted by use of both the cumulative nutrients release equation at 80℃ and the regression equation of release time needed for the same cumulative release rates between 25 and 80℃. There were only 0.3-6.9% relative errors between the tested longevity and predicted one. In conclusion, the longevity of resin coated CRFs could be predicted more quickly and precisely by use of the higher temperature short-term leaching method than that of the traditional differential release rate. The longevity of resin coated CRF could be rapidly and precisely predicted in a few hours by application of the higher temperature shortterm leaching method. 展开更多
关键词 controlled release fertilizer (CRF) water soluble resin coating longevity of CRF rapid test method
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Ponseti method compared with soft-tissue release for the management of clubfoot:A meta-analysis study 被引量:3
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作者 Marios G Lykissas Alvin H Crawford +1 位作者 Emily A Eismann Junichi Tamai 《World Journal of Orthopedics》 2013年第3期144-153,共10页
AIM: To compare the functional outcomes of patients who underwent open surgery vs Ponseti method for the management of idiopathic clubfoot and to determine whether correlations exist between functional outcome and rad... AIM: To compare the functional outcomes of patients who underwent open surgery vs Ponseti method for the management of idiopathic clubfoot and to determine whether correlations exist between functional outcome and radiographic measurements.METHODS: A meta-analysis of the literature was conducted for studies concerning primary treatment of patients with idiopathic clubfoot. We searched PubM ed Medline, EMBASE, and the Cochrane Library databases from January 1950 to October 2011. Meta-analyses were performed on outcomes from 12 studies. Pooled means, SDs, and sample sizes were either identified in the results or calculated based on the results of each study.RESULTS: Overall, 835 treated idiopathic clubfeet in 516 patients were reviewed. The average follow-up was 15.7 years. Patients managed with Ponseti method did have a higher rate of excellent or good outcome than patients treated with open surgery(0.76 and 0.62, respectively), but not quite to the point of statistical significance(Q = 3.73, P = 0.053). Age at surgery wasnot correlated with the functional outcome for the surgically treated patients(r =-0.32, P = 0.68). A larger anteroposterior talocalcaneal angle was correlated with a higher rate of excellent or good outcomes(r = 0.80, P = 0.006). There were no other significant correlations between the functional and radiographic outcomes.CONCLUSION: The Ponseti method should be considered the initial treatment of idiopathic clubfeet, and open surgery should be reserved for clubfeet that cannot be completely corrected. 展开更多
关键词 IDIOPATHIC CLUBFOOT Congenital talipes EQUINOVARUS PONSETI method Surgical release Ponseti-Laaveg score
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Interferon-gamma release assays in tuberculous uveitis:a comprehensive review 被引量:1
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作者 Usanee Tungsattayathitthan Sutasinee Boonsopon +2 位作者 Nattaporn Tesavibul Tararaj Dharakul Pitipol Choopong 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2022年第9期1520-1528,共9页
·Tuberculous uveitis(TBU)comprises a broad clinical spectrum of ocular manifestations,making its diagnosis challenging.Ophthalmologists usually require evidence from investigations to confirm or support a clinica... ·Tuberculous uveitis(TBU)comprises a broad clinical spectrum of ocular manifestations,making its diagnosis challenging.Ophthalmologists usually require evidence from investigations to confirm or support a clinical diagnosis of TBU.Since direct isolation of the causative organism from ocular specimens has limitations owing to the small volume of the ocular specimens,resultant test positivities are low in yield.Immunodiagnostic tests,including the tuberculin skin test and interferon-gamma release assays(IGRAs),can help support a clinical diagnosis of TBU.Unlike the tuberculin skin test,IGRAs are in vitro tests that require a single visit and are not affected by prior Bacillus Calmette-Guerin vaccination.Currently,available IGRAs consist of different techniques and interpretation methods.Moreover,newer generations have been developed to improve the sensitivity and ability to detect active tuberculosis.This narrative review collates salient practice points as a reference for general ophthalmologists,such as evidence for the utilization of IGRAs in patients with suspected TBU,and summarizes basic knowledge and details of clinical applications of these tests in a clinical setting. 展开更多
关键词 ocular tuberculosis tuberculous uveitis interferon-gamma release assays REVIEW
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Simulated Method on the Release of Sediment Pollutants in the Temple Lake
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作者 Sha Qian Wang Haitao Zhang Weihao 《Meteorological and Environmental Research》 CAS 2014年第1期51-54,共4页
[ Objective] The research aimed to study simulated method on the release of sediment pollutants in the Temple Lake. [ Method] For existing pollution status of the Temple Lake, sediments and overlying water were sample... [ Objective] The research aimed to study simulated method on the release of sediment pollutants in the Temple Lake. [ Method] For existing pollution status of the Temple Lake, sediments and overlying water were sampled by the integrated device. Based on the technical route, through the orthogonal test, release processes of nitrogen and phosphorus from sediment were simulated, and their release speeds were estimated under different temperatures, pH and DO in the laboratory. Relationship between environmental factor and pollutant release was explored. [ Result] The integrated device of sediment sampling and test had simple structure, cheap cost and easy operation, and sediment pollution test could be conducted without disturbing sediment after collecting sediment. Among the studied three impact factors, temperature had the maximum influence on contaminant release process, which should be considered as the important factor of future research. [ Conclusion] Compared with routine research method of sediment contaminant release from other lakes, simulated method of contaminant release from sediment in the Temple Lake had many advantaqes, which was favorable for scientific research in latter period and actual lake control. 展开更多
关键词 SEDIMENT Contaminant release Integrated device Simulated method China
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Nutrient Release Characteristics of Vinyl Chloride-Vinyl acetate Copolymers Coated SlowRelease Nitrogen Fertilizer and Its Effect on Soil Mineral Nitrogen
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作者 马洪波 许仙菊 +3 位作者 宁运旺 汪吉东 张辉 张永春 《Agricultural Science & Technology》 CAS 2014年第3期412-416,421,共6页
[Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetat... [Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetate copolymer and hydroxyl-modi- fied VCNAc were taken as coating materials to prepare slow release fertilizer. Nutri- ent release characteristics of VC/VAc slow release fertilizer was evaluated by water immersion method and the effects of VC/VAc slow release fertilizer on mineral ni- trogen were researched by pot experiment. [Result] The release periods of VC-VAc controlled-release urea and hydroxyl-modified VC/VAc coated urea were 60 and 50 d, respectively. Furthermore, the content of ammonium nitrogen reached the peak on the 30th d and the content of nitrate nitrogen reached the peak on the 60th d in soils in treatments with VCNAc and hydroxyl-modified VC/VAc; the content of nitrate nitrogen rose again on the 120th d in the treatment with VC/VAc. In terms of wheat yield, different treatments showed insignificant differences and rice yield in the treatment with VCNAc was significantly higher than that in the treatment with hy- droxyl-modified VCNAc (P〈0.05). [Conclusion] The release days of slow controlled- release fertilizer vary upon pot experiment method and water immersion method. Slow controlled-release fertilizer is not suitable for monoculture, due to long fertilizer efficiency, but multiple cropping would be optimal for its role to be fully exploited. 展开更多
关键词 Water immersion method Pot experiment method Vinyl chloride-vinyl acetate copolymer Nutrient release characteristics Soil mineral nitrogen
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Construction and Development of China’s Earthquake Information Release System 被引量:1
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作者 JI Yunda YANG Chen +1 位作者 HUANG Zhibin ZHAI Luyuan 《Earthquake Research in China》 CSCD 2019年第4期605-616,共12页
Focused on the current situation,monitoring system,technical management regulation,process,system composition,and information publication of the earthquake information release,we summarized the construction and develo... Focused on the current situation,monitoring system,technical management regulation,process,system composition,and information publication of the earthquake information release,we summarized the construction and development of China’s earthquake information release system and expected its future.In general,China’s earthquake information release systems is able to publish auto-results with MS≥3.0 from 1 to 3 minutes,M_S≥6.0 in global from 2 to 30 minutes,and formal results with MS≥3.0 in China from 8 to 30 minutes,MS≥6.0 in global from 20 to 60 minutes.These earthquake information is released by various channels such as short message,website,microblog,mobile application,etc. 展开更多
关键词 Earthquake information release Technology management regulations Process of information release System structure Information release methods
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Analysis of energy release rate for composite delaminated cylindrical shells subjected to axial compression
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作者 Jinhua Yang Yiming Fu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第6期537-546,共10页
In this paper, the postbuckling governing equations and the analytical expression of the energy release rates associated with delamination growth in a compression-loaded cylindrical shell are derived by using the vari... In this paper, the postbuckling governing equations and the analytical expression of the energy release rates associated with delamination growth in a compression-loaded cylindrical shell are derived by using the variational principle of moving boundary and the Griffith fracture criterion. The finite difference method is used to generate the postbuckling solutions of the delaminated cylindrical shells, and with these solutions, the values of the energy release rates are determined. In simulational examples, the effects of a wide range of parameters, such as delamination sizes and depths, boundary conditions, geometrical parameters, material properties and laminate stacking sequences on the energy release rates of axisymmetrical laminated cylindrical shells are intensively discussed. 展开更多
关键词 Composite cylindrical shell DELAMINATION Griffith criterion Energy release rates Finite difference method
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Numerical modelling of strength and energy release characteristics of pillar-scale coal mass
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作者 Onur Vardar Chengguo Zhang +1 位作者 Ismet Canbulat Bruce Hebblewhite 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第5期935-943,共9页
Coal burst is a manifestation of rapid energy release,which is considered as one of the most critical operational hazards in underground coal mines.This study numerically investigates the effects of discontinuities on... Coal burst is a manifestation of rapid energy release,which is considered as one of the most critical operational hazards in underground coal mines.This study numerically investigates the effects of discontinuities on the strength and energy release characteristics of coal mass samples under uniaxial compression.The universal distinct element code(UDEC)was used to model pillar-scale coal mass samples that were represented by an assembly of triangular deformable blocks,and pre-existing discontinuities such as bedding planes and cleats were also included in the models.It shows that cleat spacing can have a significant impact on compressive strength and energy release,with both strength and energy release(magnitude and rate)reducing as the number of cleats was increased.This work is one of the first attempts to numerically model and quantify the energy release which occurs during the failure of pillar-scale coal mass samples with varying cleat densities.The insights from the numerical modelling can help to understand the possible energy release mechanisms and associated coal burst potential in changing coal cleat conditions. 展开更多
关键词 Coal burst Coal clearing Energy release Distinct element method(DEM) Numerical modelling
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Optimal Release Control of Companion Satellite System Using Electromagnetic Forces
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作者 Zengwen Xu Peng Shi Yushan Zhao 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第4期27-35,共9页
Electromagnetic forces generated by the inter-action of component satellites can be used to release companion satellites. Optimal release trajectories for companion satellite system using inter-electromagnetic forces ... Electromagnetic forces generated by the inter-action of component satellites can be used to release companion satellites. Optimal release trajectories for companion satellite system using inter-electromagnetic forces were investigated. Firstly,nonlinear relative motion dynamic equations of a two-craft electromagnetic companion satellite system were derived in spatial polar coordinates. Then principles of electromagnetic satellite formation flying were introduced. Secondly,the characteristics of the electromagnetic companion satellites release were analyzed and optimal release trajectories of companion satellites using electromagnetic forces were obtained using Gauss pseudospectral method. Three performance criteria were chosen as minimum time,minimum acceleration of the separation distance and minimum control acceleration. Finally,three release examples including expansion along separation distance, rotation in orbital plane and stable formation reconfiguration were given to demonstrate the feasibility of this method. Results indicated that the release trajectories can converge to optimal solutions effectively and the concept of release companion satellites using electromagnetic forces is practicable. 展开更多
关键词 companion satellites electromagnetic formation flying optimal release trajectory Gauss pseudospectral method
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Effect of Different Remediators on the Control of Phosphorus Release from Landscape River Sediments
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作者 RONG Kun 《Journal of Landscape Research》 2017年第5期71-73,共3页
In this paper,different chemicals were added to sediments to control phosphorus release from river sediments by means of different dosing methods,thus reducing the concentration of organic pollutants in overlying wate... In this paper,different chemicals were added to sediments to control phosphorus release from river sediments by means of different dosing methods,thus reducing the concentration of organic pollutants in overlying water.Two remediators,aluminum sulfate and ferric chloride,were respectively added to six groups of experimental samples in three different covering methods,namely injection,mixing and tiling,and a control group was set up.The results showed that at the initially stationary phase of the experiment,the control effect of phosphorus release from sediments of mixing of aluminum sulfate was the most obvious,followed by tiling and injection into the mud;at the finally stationary phase of the experiment,the control effect of phosphorus release from sediments of injection of aluminum sulfate was the most obvious,followed by mixing and tiling.Under the same coverage,the inhibition effect of aluminum sulfate was more obvious than that of ferric chloride.This paper undertook research into the control effect of phosphorus release from sediments to provide a reference point for the control of water eutrophication in the days to come. 展开更多
关键词 Landscape river SEDIMENT Phosphorus release Remediator Covering method
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Energy Release Rates for Interface Cracks in Multilayered Structures
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作者 Changwei Huang Philip A.Williams 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第8期261-272,共12页
This paper examines the evolution of the interfacial deflection energy release rates in multilayered structures under four-point bending.The J-integral and the extended finite element method(XFEM)are adopted to invest... This paper examines the evolution of the interfacial deflection energy release rates in multilayered structures under four-point bending.The J-integral and the extended finite element method(XFEM)are adopted to investigate the evolution of the interfacial deflection energy release rates of composite structures.Numerical results not only verify the accuracy of analytical solutions for the steady-state interfacial deflection energy release rate,but also provide the evolutionary history of the interfacial deflection energy release rate under different crack lengths.In addition,non-dimensional parametric analyses are performed to discuss the effects of normalized ratios of the crack length,the elastic modulus,and the thickness on the interfacial deflection energy release rate.The results demonstrate that the elastic modulus ratio and thickness ratio have a distinct influence on the interfacial deflection energy release rate for multilayered beams.Furthermore,an unstable interfacial crack tends to occur for elastic multilayer beams with higher elastic modulus on the upper sub-beam under bending moments.The unstable interfacial fracture shows a decreasing interfacial deflection energy release rate with an increasing interfacial crack length. 展开更多
关键词 INTERFACIAL DEFLECTION energy release rate four-point BENDING J-INTEGRAL extended FINITE ELEMENT method
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Evolution of the Piranshahr pull-apart basin at releasing stepovers of the strike-slip fault systems in Northwest of Iran:Insights from twodimensional numerical modeling
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作者 SHOKRI Parisa ALAVI Seyed Ahmad +1 位作者 GHASSEMI Mohammad Reza GANJIANI Seyed Mehdi 《Journal of Mountain Science》 SCIE CSCD 2024年第12期4282-4298,共17页
The Piranshahr pull-apart basin,situated in the northwestern part of the Zagros Main Recent Fault(MRF),is characterized by two right-stepping segments of the dextral MRF.Here,a combination of finite element modeling t... The Piranshahr pull-apart basin,situated in the northwestern part of the Zagros Main Recent Fault(MRF),is characterized by two right-stepping segments of the dextral MRF.Here,a combination of finite element modeling techniques,especially twodimensional numerical modeling using ABAQUS software,along with field-based structural geological methods are used to assess the geometry and evolution of the pull-apart along the releasing stepovers in this strike-slip system.The utilized numerical approach applies two-dimensional(2D)finite-element modeling related to elastic Newtonian rheology to evaluate the distribution of stress and localization of strain within the pull-apart basin.This study provides valuable insights into the factors controlling the shape,as well as exploring the interaction between the pre-existing structures in this right-lateral strike-slip releasing stepover,pull-apart basin development in strike-slip systems,and stress-strain behavior by studying the impact of boundary conditions and fault overlap on the deformation pattern.The models consider three representative geometries of fault segment interactions,including underlapping,neutral,and overlapping stepovers,positioned at angles of 30°,45°,and 60°.The results indicate that increased overlap creates an extensive and elongated deformation pattern,while decrease overlap leads to block rotation and a narrow deformation pattern.In addition,the degree of overlapping between parallel strike-slip faults influences the stress and strain.The mean normal stress within the transtensional basin,located between the fault segments,exhibits an extensional nature,while the region outside the stepover experiences general compressive mean normal stresses.The Piranshahr transtensional pull-apart basin exemplifies the progressive evolution of underlapping stepovers,resulting in displaying an elongated rhomboidal to trapezoidal-shaped geometry over time. 展开更多
关键词 Main Recent Fault Piranshahr pull-apart basin releasing Stepover Finite element method ABAQUS software
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Controllable synthesis of CuAlO_(2) via solid-phase method and its catalytic performance for methanol steam reforming to hydrogen
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作者 QING Shaojun SUN Xun +3 位作者 LI Xinglong WANG Lei WU Zhiwei WANG Jianguo 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第11期1641-1651,共11页
This study explores the controllable synthesis of CuAlO_(2) using copper hydroxide and pseudo-boehmite powders as raw materials via a simple solid-phase ball milling method,along with its catalytic performance investi... This study explores the controllable synthesis of CuAlO_(2) using copper hydroxide and pseudo-boehmite powders as raw materials via a simple solid-phase ball milling method,along with its catalytic performance investigation in methanol steam reforming(MSR).Various catalysts were prepared under different conditions,such as calcination temperature,calcination atmosphere,and heating rate.Characterization techniques including BET,XRD,XPS,SEM and H2-TPR were employed to analyze the samples.The results revealed significant effects of calcination temperature on the phase compositions,specific surface area,reduction performance,and surface properties of the CA-T catalysts.Based on the findings,a synthesis route of CuAlO_(2) via the solid-phase method was proposed,highlighting the importance of high calcination temperature,nitrogen atmosphere,and low heating rate for CuAlO_(2) formation.Catalytic evaluation data demonstrated that CuAlO_(2) could catalyze MSR without pre-reduction,with the catalytic performance of CA-T catalysts being notably influenced by calcination temperature.Among the prepared catalysts,the CA-1100 catalyst exhibited the highest catalytic activity and stability.The findings of this study might be useful for the further study of the catalytic material for sustained release catalysis,including the synthesis of catalytic materials and the regulation of sustained release catalytic performance. 展开更多
关键词 CuAlO_(2) solid-phase method methanol steam reforming sustained release catalysis calcination temperature
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Rationale of Timed-Release Analysis and the Improvement of Flotation Experiment
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作者 刘炯天 周振英 +2 位作者 李备备 沈正义 王进才 《International Journal of Mining Science and Technology》 SCIE EI 1998年第2期113-117,共5页
The fundamental aspects of The Timed-Release Analysis (TRA) and some problems are analysed. Having studied the attribute of optimum flotation test results and the way of optimum test conditions, the auther put forward... The fundamental aspects of The Timed-Release Analysis (TRA) and some problems are analysed. Having studied the attribute of optimum flotation test results and the way of optimum test conditions, the auther put forward a proposal to improve this test method by adding a new test step of scavenging flotation and using optimum test conditions varied with different fine coals instead of the given ones settled by the TRA norm. Comparison between test results of the two methods of TRA shows that the improved method is very good. 展开更多
关键词 laboratory COAL FLOTATION TEST method timed-release ANALYSIS optimization of TEST conditions optimum results of COAL FLOTATION
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Evaluation of the cell cytotoxity of biomaterials in vitro by using the ^( 125)I-UdR-release-test
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作者 LU Xiao-ying~1,XUE Miao~2,XU Shu-qing~2 《Chinese Journal of Biomedical Engineering(English Edition)》 2002年第3期113-118,共6页
The ~ 125 I-UdR-release method is used for evaluation of the cytotoxity of biomaterials. In this method, K562 cells cultured in suspending were used to make a direct contact with materials. The cytotoxity of 14 kinds ... The ~ 125 I-UdR-release method is used for evaluation of the cytotoxity of biomaterials. In this method, K562 cells cultured in suspending were used to make a direct contact with materials. The cytotoxity of 14 kinds of biomaterials has been evaluated using this method. In comparing with other experimental methods for the evaluation of cell cytotoxity, this method shows advantages of the celerity, the simplicity, the objective, the accuracy and the quantitative. 展开更多
关键词 I-UdR-release method biomaterial CYTOTOXITY
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Use of Plastic Correction Formula to Improve Accuracy of Welding Residual Stress Test with Blind-Hole Method 被引量:3
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作者 Qiu Zhao Kongsheng Chen +3 位作者 Meizhong Chen Bruno Briseghella Zhiyong Guo Guotao Yang 《Transactions of Tianjin University》 EI CAS 2018年第5期480-488,共9页
The blind-hole method is the most widely used approach to experimentally determine the distribution of residual stress. This paper aims to improve test accuracy of welding residual stress and conducts an experimental ... The blind-hole method is the most widely used approach to experimentally determine the distribution of residual stress. This paper aims to improve test accuracy of welding residual stress and conducts an experimental study on the strain release factors involved when using the blind-hole method for Q235 and Q345, two steels commonly used in building structures. The ranges of strain release factors A and B in the elastic stage, the effects of strain release factors on residual stress calculated values, and the plastic corrected strain release factors are analyzed considering of the effect of plastic deformation around the blind hole on measurement accuracy. Finally, a simplified calculation formula to determine strain release factors is proposed for use with the blind-hole method. Results show that in the elastic stage, strain release factor A for Q235 and Q345 ranges from-0.399 to-0.525 and strain release factor B from-0.791 to-0.960. Changing the strain release factors A and B shows that calculated residual tensile stress varies in relation to a decrease in both factor values. However, there is a increase in calculated residual compressive stress with a decrease in the strain release factor A value, but there is an decrease with a decrease in strain release factor B value. Calculated residual stress applied to elastic strain release factors is compared with that applied to amended plastic strain release factors for Q235 steel. The maximum deviation between calculated residual stress and test stress is reduced from 21.1 to 1.0%,and for Q345 steel from 26.5 to 1.2%. It is thus evident that the plastic correction formula proposed in this paper can be used in calculations when conducting a residual stress test. 展开更多
关键词 Blind-hole method WELDING RESIDUAL stress·Calibration test STRAIN release factor PLASTIC CORRECTION
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Response of Tomato Plants to a New Application Method of Polyolefin-Coated Fertilizer 被引量:3
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作者 TIAN Xiao-Hong M. SAIGUSA 《Pedosphere》 SCIE CAS CSCD 2005年第4期491-498,共8页
The response of tomato (Lycopersicon esculentum) plants basically fertilized with 0.3 g N per plant of compound fertilizer with a N:P2O5:K2O ratio of 20:10:20 to sticks of polyolefin-coated fertilizer (POCF) ... The response of tomato (Lycopersicon esculentum) plants basically fertilized with 0.3 g N per plant of compound fertilizer with a N:P2O5:K2O ratio of 20:10:20 to sticks of polyolefin-coated fertilizer (POCF) (LongT0 with a N:P2Os:K2O ratio of 14:12:14) applied 23 d after transplanting was investigated using rooting boxes in the greenhouse. The results at 26 and 40 d after stick fertilizer treatment showed that the use of the stick fertilizer greatly increased the production of many new fine roots from the tomato plants. Compared to the unfertilized control, root length and root length density in the stick fertilizer treatment increased by 3.6-6.7 fold. In the soil zones near the stick fertilizer, root weight and root mass density were also significantly higher for the stick fertilizer treatment. Additionally, the use of the stick fertilizer increased the N, P and K concentrations in the leaves and stems of the tomato plants. The new fine roots growing near the stick fertilizer not only absorbed more nutrients and translocated them to the shoots, but also contained more nutrients within themselves. The soil ammonium and nitrate N data showed that N released from the stick fertilizer played a major role in inducing the production of new fine roots. These results indicated that stick fertilizer could be used as an alternative to the co-situs application technique to change and control the root distribution of crops as well as to increase the potential capacity of roots for water and nutrient absorption. 展开更多
关键词 application method controlled release fertilizer tomato (Lycopersicon esculentum)
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Non-complete relief method for measuring surface stresses in surrounding rocks 被引量:4
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作者 张凤鹏 邱兆国 冯夏庭 《Journal of Central South University》 SCIE EI CAS 2014年第9期3665-3673,共9页
The measurement of surface stresses in surrounding rocks with the use of a relief method of annular hole-drilling was studied by numerical analysis. The stress relief process by hole-drilling was then simulated with t... The measurement of surface stresses in surrounding rocks with the use of a relief method of annular hole-drilling was studied by numerical analysis. The stress relief process by hole-drilling was then simulated with the use of finite element method. The influences of the borehole diameter(d), the initial stresses and the ratio of the initial principle stresses on the variations of the remained stress and the released stress in function of the relief depth(h) were discussed. The relation between the non-dimensional ratio of the released principle strains and that of the initial principle stresses, and the effect of the elastic modulus and the Poisson ratio of the rock mass on the stress relief curves were studied. The results show that the stress relief behavior formulated with the non-dimensional ratio of the released stress and the ratio of h/d is only sensitive to the ratio of the initial principle stresses and the Poisson ratio. The stresses are completely released when h equals 1.6d, and the tensile stresses take place on the bore core surface in the relief measurement process. Finally, a non-complete relief method of annular hole-drilling for measuring surface stress in surrounding rocks is proposed and the procedure is presented. 展开更多
关键词 non-complete relief method surface stress in surrounding rock stress relief rate ratio of initial principal stresses ratioof released principal strains
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Influence of polymer solution on the morphology and local structure of NH_(4)ZnPO_(4)powders synthesized by a simple precipitation method at room temperature
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作者 Santi Phumying Thongsuk Sichumsaeng +4 位作者 Pinit Kidkhunthod Narong Chanlek Jessada Khajonrit Somchai Sonsupap Santi Maensiri 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第2期298-304,共7页
NH_(4)Zn PO_(4)powders were synthesized using a simple precipitation method at room temperature.The effects of polyvinyl pyrrolidone(PVP),polyvinyl alcohol(PVA),glucose,and hexadecyltrimethylammonium bromide(CTAB)solu... NH_(4)Zn PO_(4)powders were synthesized using a simple precipitation method at room temperature.The effects of polyvinyl pyrrolidone(PVP),polyvinyl alcohol(PVA),glucose,and hexadecyltrimethylammonium bromide(CTAB)solutions on the morphology and structure of the prepared samples were investigated.The phase composition and morphology of the prepared samples were characterized using X-ray diffraction and scanning electron microscopy,respectively.Depending on the polymer sources,the hexagonal structure prepared using non-surfactant of water completely changed to monoclinic structure when CTAB was added.X-ray absorption near-edge structure(XANES)and X-ray photoelectron spectroscopy(XPS)were performed to study the local structure and surface electronic structure of the prepared samples,confirming that the oxidation states of P and Zn ions are^(5+)and^(2+),respectively.On the basis of the results of inductively coupled plasma atomic emission spectroscopy(ICP-OES),the NH_(4)Zn PO_(4)powders can be classified as a slow-release fertilizer where less than 15%of the ions were released in 24 h.A simple precipitation method using water,PVP,PVA,sucrose,and CTAB as a template can be used to synthesize NH4 Zn PO4 powders.In addition,this method may be extended for the preparation of other oxide materials. 展开更多
关键词 ammonium zinc phosphate precipitation method MORPHOLOGY X-ray absorption spectroscopy ion release properties
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