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211.
The thermal conductivities of compacted bentonite and a bentonite–sand mixture were measured to investigate the effects of
dry density, water content and sand fraction on the thermal conductivity. A single expression has been proposed to describe
the thermal conductivity of the compacted bentonite and the bentonite–sand mixture once their primary parameters such as dry
density, water content and sand fraction are known. 相似文献
212.
Hae-Jung Chae Geum-Jin Kim Barsha Deshar Hyun-Jin Kim Min-Ji Shin Hyukbean Kwon Ui-Joung Youn Joo-Won Nam Sung-Hak Kim Hyukjae Choi Sung-Suk Suh 《Molecules (Basel, Switzerland)》2021,26(13)
Colorectal cancer is one of the life-threatening ailments causing high mortality and morbidity worldwide. Despite the innovation in medical genetics, the prognosis for metastatic colorectal cancer in patients remains unsatisfactory. Recently, lichens have attracted the attention of researchers in the search for targets to fight against cancer. Lichens are considered mines of thousands of metabolites. Researchers have reported that lichen-derived metabolites demonstrated biological effects, such as anticancer, antiviral, anti-inflammatory, antibacterial, analgesic, antipyretic, antiproliferative, and cytotoxic, on various cell lines. However, the exploration of the biological activities of lichens’ metabolites is limited. Thus, the main objective of our study was to evaluate the anticancer effect of secondary metabolites isolated from lichen (Usnea barbata 2017-KL-10) on the human colorectal cancer cell line HCT116. In this study, 2OCAA exhibited concentration-dependent anticancer activities by suppressing antiapoptotic genes, such as MCL-1, and inducing apoptotic genes, such as BAX, TP53, and CDKN1A(p21). Moreover, 2OCAA inhibited the migration and invasion of colorectal cancer cells in a concentration-dependent manner. Taken together, these data suggest that 2OCAA is a better therapeutic candidate for colorectal cancer. 相似文献
213.
Summary In a hybrid laminate containing an interfacial crack between piezoelectric and orthotropic layers, the dynamic field intensity
factors and energy release rates are obtained for electro-mechanical impact loading. The analysis is performed within the
framework of linear piezoelectricity. By using integral transform techniques, the problem is reduced to the solution of a
Fredholm integral equation of the second kind, which is obtained from one pair of dual integral equations. Numerical results
for the dynamic stress intensity factor show the influence of the geometry and electric field.
Received 29 June 2001; accepted for publication 3 December 2001 相似文献
214.
215.
This study investigates students' retention of mathematical knowledge and skills in two differential equations classes. Posttests and delayed posttests after 1 year were administered to students in inquiry‐oriented and traditional classes. The results show that students in the inquiry‐oriented class retained conceptual knowledge, as seen by their performance on modeling problems, and retained equal proficiency in procedural problems, when compared with students in the traditionally taught classes. The results of this study add additional support to the claim that teaching for conceptual understanding can lead to longer retention of mathematical knowledge. 相似文献
216.
According to the Zipf’s law, the distribution of rank-ordered frequency of words in the natural language can be modelled on the power law. In this paper, we examine the frequency distribution of 64 codons over the coding and non-coding regions of 88 DNA from EMBL and GenBank database, using exponential fitting. Also, we regard 20 amino-acids as vocabulary, perform the same frequency analysis to the same database and show that amino-acids can be used as biological meaningful words for Zipf’s approach. Our analysis suggests that a natural language structure may exist not only in the coding region of DNA but in the non-coding one of DNA. 相似文献
217.
Joongsung Kwon 《Journal of Applied Mathematics and Computing》1998,5(1):153-161
We study limits of sums of fuzzy numbers with different spreads and different shape functions, where addition is defined by the sup-t-norm. We show the existence of the limit of the series of fuzzy numbers and prove the uniform continuity of the limit. Finally we investigate a law of large numbers for sequences of fuzzy numbers. 相似文献
218.
Summary A finite crack propagating at constant speed in a functionally graded piezoelectric strip (FGPS) bonded to a homogeneous piezoelectric strip is considered. It is assumed that the electroelastic material properties of the FGPS vary exponentially across the thickness of the strip, and that the bimaterial strip is under combined anti-plane mechanical shear and in-plane electrical loads. The analysis is conducted for the electrically unified crack boundary condition, which includes both the traditional permeable and the impermeable ones. By using the Fourier transform, the problem is reduced to the solution of Fredholm integral equations of the second kind. Numerical results for the stress intensity factor and the crack sliding displacement are presented to show the influences of the crack propagation speed, electric loads, FGPS gradation, crack length, electromechanical coupling coefficient, properties of the bonded homogeneous piezoelectric strip and crack location. 相似文献
219.
Yoon Soo Han Sang Dae Kim Lee Soon Park Dong Uk Kim Younghwan Kwon 《Journal of polymer science. Part A, Polymer chemistry》2003,41(16):2502-2511
Four different types of conjugated copolymers, consisting of alternating structures of phenothiazinylene vinylene and phenylene vinylene derivatives such as phenylene vinylene, 1,1′‐biphenyl‐4,4′‐ylene vinylene, 2‐methoxy‐5‐(2‐ethylhexyloxy)‐1,4‐phenylene vinylene, and 9,10‐anthrylene vinylene, were prepared by Horner–Emmons condensation between appropriate diphosphonates and dialdehydes. Single‐layer and double‐layer light‐emitting diodes were fabricated with the synthesized conjugated polymers, and their electroluminescent properties were investigated. Poly(N‐2‐ethylhexyl‐3,6‐phenothiazinylene vinylene‐alt‐9,10‐anthrylene vinylene), containing phenothiazinylene vinylene and anthrylene vinylene as repeat units, emitted a reddish‐orange color with Commission Internationale de l'Eclairage coordinates of x = 0.6173 and y = 0.3814 that was very similar to the National Television System Committee standard red, and it showed a bipolar carrier‐injection/transporting capability caused by electron‐withdrawing anthracene and electron‐donating amino groups. Poly[N‐2‐ethylhexyl‐3,6‐phenothiazinylene vinylene‐alt‐2‐methoxy‐5‐(2‐ethylhexyloxy)‐1,4‐phenylene vinylene], containing phenothiazinylene vinylene and dialkoxy phenylene vinylene moieties, showed excellent hole‐injection/transporting capability. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2502–2511, 2003 相似文献
220.
S.-M. Kwon H.-S. Choi K.-Y. Lee 《Archive of Applied Mechanics (Ingenieur Archiv)》2002,72(2-3):160-170
Summary The steady-state of a propagation eccentric crack in a piezoelectric ceramic strip bonded between two elastic materials under
combined anti-plane mechanical shear and in-plane electrical loadings is considered in this paper. The analysis based on the
integral transform approach is conducted on the permeable crack condition. Field intensity factors and energy release rate
are obtained in terms of a Fredholm integral equation of the second kind. It is shown for this geometry that the crack propagation
speed has influence on the dynamic energy release rate. The initial crack branching angle for a PZT-5H piezoceramic structure
is predicted by the maximum energy release rate criterion.
Received 23 January 2001; accepted for publication 18 October 2001 相似文献