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排序方式: 共有137条查询结果,搜索用时 31 毫秒
1.
Attila Varga Istvan Keppler Laszlo Fenyvesi 《Journal of Mechanical Science and Technology》2020,34(6):2327-2332
Our goal is the determination of the material flow processes around the mixing screws and introducing a new mixing index which can characterize the perform 相似文献
2.
Back Cover: Lipopeptide Nanoparticles: Development of Vaccines against Hookworm Parasite (ChemMedChem 10/2015) 下载免费PDF全文
3.
研究了不同改性水平的γ-聚谷氨酸(以下简写为γ-PGA)吸附去除水体中重金属离子Pb2+的性能影响。研究结果表明,交联改性后的γ-PGA与未改性的γ-PGA相比,具有更好的Pb2+吸附性能,在将改性γ-PGA加入到含有Pb2+的水体中并均匀混合之后,随着交联度的提高,改性γ-PGA吸附Pb2+的性能逐渐增加,但在吸附最终结束时,不同改性的γ-PGA对Pb2+吸附去除率均在99%以上。在吸附去除Pb2+影响因素分析中发现Pb2+初始质量浓度和溶液pH对不同改性的γ-PGA吸附去除Pb2+性能的影响较大。随着Pb2+质量浓度的增加,不同改性水平γ-PGA对Pb2+的去除率均略有一定程度的下降。当溶液的pH控制在中性或者偏碱性时,25%改性γ-PGA对Pb2+的去除率能够保持在99%以上,当pH降至4.5和3时,Pb2+去除率分别降为90.76%和78.46%。 相似文献
4.
Codruta Soica Corina Danciu Germaine Savoiu-Balint Florin Borcan Rita Ambrus Istvan Zupko Florina Bojin Dorina Coricovac Sorina Ciurlea Stefana Avram Cristina Adriana Dehelean Teodora Olariu Petru Matusz 《International journal of molecular sciences》2014,15(5):8235-8255
Betulinic acid, a very promising anti-melanoma agent, has very low water solubility that causes low bioavailability. To overcome this inconvenience, a highly water-soluble cyclodextrin was used (octakis-[6-deoxy-6-(2-sulfanyl ethanesulfonic acid)]-γ-cyclodextrin). The complex was physico-chemically analyzed using differential scanning calorimetry (DSC), X-ray and scanning electron microscopy (SEM) methods and then in vitro tested for its antiproliferative activity by the MTT assay and by cell cycle analysis. Finally, the complex was tested in vivo using an animal model of murine melanoma developed in C57BL/6J mice, where it caused a reduction in tumor volume and weight. The study revealed the beneficial influence of betulinic acid inclusion into the cyclodextrin in terms of antiproliferative activity and in vivo tumor development. 相似文献
5.
The present study examined the relationship between a set of individual and contextual variables and high-risk alcohol use among young offenders placed on community orders in New South Wales, Australia. Participants (n = 777) were compared on a set of factors known to be strong predictors of high-risk alcohol use among adolescents. The authors assessed the strength of the relationship between gender, age, ethnicity, geographical region of residence, school attendance, father absence, history of childhood trauma, and the presence of severe conduct disorder on weekly levels of alcohol use. Living in rural locations, not currently attending school, being female, and not having been raised with a biological father present were associated with significantly increased odds of alcohol abuse. Father absence was a more important risk factor for rural young offenders, but school dropout was associated with more hazardous drinking among young offenders in urban areas. Accordingly, the authors suggest family-focused intervention programs for young offenders living in rural areas and school-based programs for vulnerable young people living in urban areas, although programs should consider including both factors for both groups if feasible and warranted. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Microstructural and magnetic properties changes of a metastable ferritic–austenitic stainless steel due to cold rolling were
studied together with the possibility to develop a new ferritic–martensitic stainless steel. In order to reduce costs low-Ni
content was maintained in the lean duplex stainless steel considered, making it more susceptible to strain-induced martensitic
transformation. In this study a practically complete γ → α′ transformation was found for 80% of thickness reduction, resulting
a new two-phase ferritic–α′ martensitic stainless steel. To investigate the structural evolution different values of thickness
reduction were applied. Light optical and scanning electron microscopy were performed to characterize the morphology and grain
refining of the structure after each rolling step. Martensitic transformation and work hardening were detected and analyzed
by studying of magnetic properties (saturation magnetic polarization, relative magnetic permeability, coercivity). Additionally,
hardness tests were performed. The results highlighted a strong grain refining and increase in martensitic phase and hardness
with increasing cold deformation. A direct relationship between microstructure and magnetic properties was revealed. In particular
the reciprocal of relative magnetic permeability and the coercivity increased with martensite content and the amount of cold
deformation. Therefore, the possible application of magnetic measurements as non-destructive tests to study microstructural
evolution during cold rolling was shown for the steel considered. 相似文献
7.
Istvan Kucora Pera Paunjoric Jasna Tolmac Marko Vulovic James G. Speight 《Petroleum Science and Technology》2017,35(3):213-221
In the petrochemical industry, an industrial pyrolysis furnace is a complicated piece of equipment that functions as both a reactor and high-pressure steam generator. During service, hard deposits of carbon (coke) build up on the inner wall of the tube, reducing heat transfer and restricting the flow of the hydrocarbon feedstocks. In this paper, an overview of coke formation, the impact of coke formation, and the methods by which coke formation can be prevented, as well as methods that can be successful in decoking of pyrolysis furnaces, is presented. 相似文献
8.
Golsa Samii-Saket Jeffrey G. Boersma Gary R. Ablett Duane E. Falk Ron Fletcher Istvan Rajcan 《Journal of the American Oil Chemists' Society》2011,88(11):1795-1798
Development of high oil soybeans would reduce the cost of soybean oil production for biodiesel or edible oil applications.
An accurate determination of soybean seed oil concentration is essential especially when developing superior cultivars with
increased seed oil content. The objective of this study was to develop an oil measurement method for single seeds using NMR
spectrometry. An NMR spectrometer was calibrated using commercial cooking oil. Fifteen cultivars of known mean oil content
were used to evaluate the calibration curves. The calibration curves developed had a correlation coefficient of 0.99. It was
found that soybean and corn oil gave identical results over the calibrated interval. 相似文献
9.
The catalytic activity and selectivity of three PdO-MoO3/-Al2O3 catalysts containing about 2% Pd and 2% Mo were studied for the reduction of NO by h2 in the presence of varying amounts of oxygen at temperatures from 50 to 550 °C. The results are compared with those for PdO/-Al2O3, PdO-MoO3/-Al2O3 containing 2% Pd and 20% Mo, and a commercial Pt-Rh catalyst. In the absence of oxygen, the conversion of NO to N2 and N2O is higher on the three catalysts than it is on PdO/-Al2O3 at 500 and 550 °C. In the presence of oxygen, the yields of N2 and N2O are generally lower on two of the PdO-MoO3/-Al2O3 catalysts than on PdO/-Al2O3. 相似文献
10.
Automatic Verification of a Behavioural Subset of UML Statechart Diagrams Using the SPIN Model-checker 总被引:8,自引:0,他引:8
Statechart Diagrams provide a graphical notation for describing dynamic aspects of system behaviour within the Unified Modelling
Language (UML). In this paper we present a translation from a subset of UML Statechart Diagrams - covering essential aspects
of both concurrent behaviour, like sequentialisation, parallelism, non-determinism and priority, and state refinement - into
PROMELA, the specification language of the SPIN model checker. SPIN is one of the most advanced analysis and verification
tools available nowadays. Our translation allows for the automatic verification of UML Statechart Diagrams. The translation
is simple, proven correct, and promising in terms of state space representation efficiency.
Received September 1999 / Accepted in revised form February 2000 相似文献