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71.
1 INTRODUCTIONAntimonymercaptides[1~ 4 ] usedasheatstabiliz erisattractivenotonlyforitsrelativelylowcost ,butalsoforitssimilarstabilizingeffectcomparedwiththatofthemostexcellentone organotin .Bymakingfulluseoftheplentifulantimonyresource ,developingantimonym… 相似文献
72.
Daily values of H/H0, the ratio of total horizontal radiation to that outside the atmosphere has been correlated with s/S, bright sunshine as a fraction of daylength for 3 yr measurements in Adana and Ankara, Turkey. Using a maximum-likelihood quadratic fit, we show that monthly averages s/S and its standard deviation σs/S can be used to estimate the monthly average H/H0 as Comparison of the estimations of the above equation with measurements from different regions of Turkey indicate that less than 5 per cent relative error is possible. A further correlation σ2s/S with s/S makes it possible to estimate H/H0 with just the knowledge of s/S. 相似文献
H/H0 = 0.204 + 0.758s/S − 0.250[s/S2 + σ2s/S.
73.
Tolga Taner Mecit Sivrioğlu Hüseyin Topal Ahmet Selim Dalkılıç Somchai Wongwises 《Sadhana》2018,43(3):42
This study presents a case study of energy management in a sugar factory in Turkey. The main idea of the study is to analyse energy consumption, the quantity of material production, and figure out a suitable energy efficiency for the case study of a sugar factory subsequently. Firstly, a material production and energy consumption audit were performed for the sugar factory. Secondly, energy efficiency was calculated from the energy data. The SPSS (Statistical Package for the Social Sciences) statistical software was used to ensure the accuracy of the data. The factory’s energy consumption was calculated as 43,590.25 toe (tons of oil equivalent) over the last year. These results were used for CUSUM (Cumulative Sum Deviation Method) graphics. This research poses the consumption of energy, cost of energy and the relationship between energy usage and material production of sugar. The unit of energy cost was 688.22 [$/toe] for the last year. This result showed that the factory decreased the unit of energy by optimisation. The results indicated that the investigated sugar factory should pay attention to the energy management issue in order to comply with the Energy Efficiency of Turkish Law and Directives. 相似文献
74.
Polyester particles in concrete are preferred because they provide thermal, chemical and water resistance. In this study, thermal conductivity, electrical resistivity, mechanical strength and water resistance properties of concretes containing polyester granules such as flame-retardant polyester, cationic dyeable polyester and polyester with a low melting point-filled concrete have been analyzed using a full factorial design via Minitab® version 17. The effect of the most influential factors on thermal conductivity of polyester aggregate reinforced concrete composite has been determined as an interaction between the cationic dyeable and low-melt–point polyester. This mixture is suitable for production of thermal insulating concrete. Moreover, it is concluded that cationic dyeable polyester is the highest corrosion- and water-resistant product among the polyesters used in this study. The recovery rate of 33.94% in the thermal conductivity and 214.89% in the electrical resistivity of polyester-reinforced concrete composites has been obtained with a 28-day compressive strength loss of 41.94% according to the reference concrete in the full factorial design application. These results indicate that the polyester-reinforced concrete composites are quite effective in achieving thermal and corrosion resistance concrete but with noticeable compressive strength loss. 相似文献
75.
Yavuz Emre Arslan Yusuf Furkan Galata Tugba Sezgin Arslan Burak Derkus 《Journal of materials science. Materials in medicine》2018,29(8):127
In this study, we aimed at fabricating decellularized bovine myocardial extracellular matrix-based films (dMEbF) for cardiac tissue engineering (CTE). The decellularization process was carried out utilizing four consecutive stages including hypotonic treatment, detergent treatment, enzymatic digestion and decontamination, respectively. In order to fabricate the dMEbF, dBM were digested with pepsin and gelation process was conducted. dMEbF were then crosslinked with N-hydroxysuccinimide/1-Ethyl-3-(3-dimethylaminopropyl)-carbodiimide (NHS/EDC) to increase their durability. Nuclear contents of native BM and decellularized BM (dBM) tissues were determined with DNA content analysis and agarose-gel electrophoresis. Cell viability on dMEbF for 3rd, 7th, and 14th days was assessed by MTT assay. Cell attachment on dMEbF was also studied by scanning electron microscopy. Trans-differentiation capacity of human adipose-derived mesenchymal stem cells (hAMSCs) into cardiomyocyte-like cells on dMEbF were also evaluated by histochemical and immunohistochemical analyses. DNA contents for native and dBM were, respectively, found as 886.11?±?164.85 and 47.66?±?0.09?ng/mg dry weight, indicating a successful decellularization process. The results of glycosaminoglycan and hydroxyproline assay, and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), performed in order to characterize the extracellular matrix (ECM) composition of native and dBM tissue, showed that the BM matrix was not damaged during the proposed method. Lastly, regarding the histological study, dMEbF not only mimics native ECM, but also induces the stem cells into cardiomyocyte-like cells phenotype which brings it the potential of use in CTE. 相似文献
76.
Muhammed Uludağ 《Dynamical Systems: An International Journal》2018,33(3):497-518
We explore the dynamics of a 1-parameter family of continued fraction maps of the unit interval. The family contains as special instances the Gauss continued fraction map and the Fibonacci map. We determine the transfer operators of these dynamical maps and prove that the Denjoy–Minkowski measure is a common invariant measure of the family. We show that their analytic invariant measures obey a common functional equation generalizing Lewis’ functional equation and we find a.c. invariant measures for some members of the family. We also discuss a certain involution of this family which sends the Gauss map to the Fibonacci map relating Riemann's zeta function to the so-called Fibonacci zeta function. 相似文献
77.
Internal nitride dispersion strengthened superalloy is a new type of high performance superalloy for combustion chamber. The background and development of this alloy were firstly introduced. And then the microstructure and properties of NS163 which is a typical internal nitride dispersion strengthened alloy were investigated. The results show that the microstructure of NS163 is simple in the temperature range of 900??1250??, which is composed of austenite matrix and MC carbide. The recrystallization behavior of the cold- rolled sheet under the test condition was studied systematically. It is found that the solid solution temperature of the finished product should be 1200??, and after solid solution at 1200??, the sheet has 5 grade average grain size, excellent cold workability and low tensile strength at high temperature. The above results can help to optimize the microstructure of NS163 alloy sheet before nitriding and provide a basis for the evaluation of the strengthening effect of the alloy after internal nitriding. 相似文献
78.
In this study, experimental neutron-emission spectra produced by (n, xn) reactions on nuclei 232Th have been compared with experimental 238U(n, xn) neutron-emission spectra from 2 to 18 MeV. Angle-integrated cross-sections in neutron induced reactions on targets 238U have been calculated at the bombarding energies from 2 to 18 MeV. In the calculations, the geometry dependent hybrid model and the cascade exciton model including the effects of pre-equilibrium have been used. In addition, we have described how multiple pre-equilibrium emissions can be included in the Feshbach–Kerman-Koonin (FKK) fully quantum-mechanical theory. By analyzing (n, xn) reaction on 238U with the incident energy from 2 to 18 MeV, the importance of multiple pre-equilibrium emission can be seen clearly. All calculated results have been compared with experimental data. The obtained results have been discussed and compared with the available experimental data and found agreement with each other. 相似文献
79.
Mehmet Kodal Hümeyra Şirin Bağdagül Karaağaç Güralp Özkoç 《Polymer Engineering and Science》2020,60(8):1958-1972
The aim of this article is to improve the interfacial adhesion between silicone rubber (SR) and Rayon fiber by the help of functional hybrid POSS nanoparticles. Two POSS types were compared, octavinyl-POSS (O-POSS) and methacryl-POSS (M-POSS), having reactive CC double bonds that can impart in peroxide crosslinking. O-POSS is nonpolar, whereas M-POSS is polar and is able to make H-bond with Rayon fibers. POSS type and their concentrations were examined as the experimental parameters. H-adhesion tests indicated that both POSS types enhanced the adhesion of SR composites to Rayon fibers compared with control recipe. Specifically, slightly higher values were obtained with the use of M-POSS. It was observed that both O-POSS and M-POSS slowed down the curing rate but increased the degree of crosslinking. The cure extent of O-POSS containing composites was found to be higher than that of M-POSS containing ones. Thermal gravimetric analyses revealed that thermal stability of SR composites was significantly improved by the addition of POSS particles. Higher char yield and degradation temperatures were obtained with O-POSS at higher loadings with respect to M-POSS. The POSS distribution at lower loading levels was found to be homogenous for both POSS types as observed from scanning electron microscope and transmission electron microscope. 相似文献
80.
Kilicaslan M. Fatih Altaib Salaheddin Salem Vurdu Can Doğan 《Metals and Materials International》2019,25(6):1457-1466
Metals and Materials International - In this project the morphology and microstructure of both conventional cast and melt spun of Al–20Si–9Fe–1.2Nb and... 相似文献