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31.
Turgay Sekin Bülent Alici Engin etinkaya Ismail
zdemir 《Journal of polymer science. Part A, Polymer chemistry》1997,35(12):2411-2420
Novel vinyl monomers containing 1,4,5,6-tetrahydropyrimidine were prepared by the reaction of N-substituted-1,3-diaminopropane with N,N-dimethyl-formamide dimethylacetal, which gave 1-alkyl or aryl substituted 1,4,5,6-tetrahydropyrimidines, Alkylation of the tetrahydropyrimidine derivatives by chloromethylstyrene produces the N-methyl-N′-vinyl benzyl-1,4,5,6-tetrahydropyrimidinium chloride in high yields. These monomers were readily polymerized in dimethylformamide by AIBN at 80°C. Homopolymers and soluble linear copolymers were prepared and copolymerization parameters were rationalized. Further, insoluble terpolymers prepared from these monomers, styrene and divinylbenzene were tested for the sorption of the weakly acidic gases gave excellent results. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2411–2420, 1997 相似文献
32.
A new sulfonated copolymers containing congo red groups were synthesized as a potential electrolyte for high temperature PEFCs. The resulting cross-linked sulfonated hybrid congo red membranes showed greatly improved water stability in comparison with the uncrosslinked ones while high proton conductivity was maintained. sulfonated membranes have been tested with respect to fuel cell performance. Short term fuel cell test for 100 hr gave a stable performance. These membranes are less expensive compared to Nafion. New sulfonated proton exchange composites membranes were used biological fuel cells. Molasses which is the waste of sugar factory, was used in anode as fuel and different bacteria species was sowing. Potential change was reported in biological fuel cells. 相似文献
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34.
Silica‐supported catalytically active functional materials, such as the rhodium(I) carbene complex with 1‐(triethoxysilylpropyl)‐3‐(2,4,6‐trimethylbenzyl)imidazolidine‐2‐ylidine (L), were prepared using the sol–gel method. The complex ( 1 ; COD = 1,5‐cyclooctadiene) RhCl(COD)[1‐(triethoxysilylpropyl)‐3‐(2,4,6‐trimethylbenzyl)imidazolidin‐2‐ylidine] was characterized by conventional spectroscopic methods and elemental analyses and the silica‐supported functional material RhCl(COD)(L) were tested for the catalytic addition of phenylboronic acid to aldehydes. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
35.
We treat the classical dynamics of the hydrogen atom in perpendicular electric and magnetic fields as a celestial mechanics problem. By expressing the Hamiltonian in appropriate action–angle variables, we separate the different time scales of the motion. The method of averaging then allows us to reduce the system to two degrees of freedom, and to classify the most important periodic orbits. 相似文献
36.
A novel mesoporous silica‐nanotube‐supported 3‐4,5‐dihydroimidazol‐1‐yl‐propyltriethoxysilanedichloropalladium(II) complex was prepared and characterized. 3‐4,5‐Dihydroimidazol‐1‐yl‐propyltriethoxysilanedichloropalladium(II) and mesoporous silica‐supported 3‐4,5‐dihydroimidazol‐1‐yl‐propyltriethoxysilanedichloropalladium(II) were tested for catalytic activity for Heck coupling reactions between styrene and several aryl halides and Suzuki coupling reactions between phenylboronic acid and several aryl halides. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
37.
Preparation and characterization of activated carbon produced from pomegranate seeds by ZnCl2 activation 总被引:1,自引:0,他引:1
In this study, pomegranate seeds, a by-product of fruit juice industry, were used as precursor for the preparation of activated carbon by chemical activation with ZnCl2. The influence of process variables such as the carbonization temperature and the impregnation ratio on textural and chemical-surface properties of the activated carbons was studied. When using the 2.0 impregnation ratio at the carbonization temperature of 600 °C, the specific surface area of the resultant carbon is as high as 978.8 m2 g−1. The results showed that the surface area and total pore volume of the activated carbons at the lowest impregnation ratio and the carbonization temperature were achieved as high as 709.4 m2 g−1 and 0.329 cm3 g−1. The surface area was strongly influenced by the impregnation ratio of activation reagent and the subsequent carbonization temperature. 相似文献
38.
Essential hypertension is a multifactorial disease in which genetic and enviromental factors play an important role. These factors differ in each population. As there are no existing data for the Turkish population, we investigated four Renin Angiotensin System (RAS) gene polymorphisms, the angiotensin converting enzyme (ACE), angiotensinogen (AGN) M235T/T174M and angiotensin II type 1 receptor A1166C polymorphism in 109 hypertensive and 86 normotensive Turkish subjects. Polymerase Chain Reaction (PCR) and Restriction Fragment Length Polymorphism (RFLP), and agarose gel electrophoresis tecniques were used to determine these polymorphism. The frequencies of person that carry ACE D allel (DD+ID) was significantly higher in hypertensive group (99.1%) than controls (80%) (P 0.000). M235T TT genotype was also found significantly higher in hypertensives than control group (20% vs 2.7%; P 0.001). The frequency of AGN 174M allele was higher in the hypertensive group than control subjects (8.76% vs 4.81%). Frequency of ATR1 C allele (AC+CC genotypes) was found higher hypertensives than controls (39.4% vs 25.9%; P = 0.054). Our results suggest that an interaction exists between the RAS genes and hypertension in Turkish population. 相似文献
39.
Muzeyyen Dogan Emel Eryuksel Ismail Kocak Turgay Celikel Mehmet Ali Sehitoglu 《Journal of voice》2007,21(2):224-230
OBJECTIVES: To evaluate the voice quality in patients with mild-to-moderate asthma by subjective and objective methods. STUDY DESIGN: Comparative, controlled, cross-sectional study. METHODS: Patients with mild-to-moderate asthma (n=40) and age- and sex-matched healthy controls (n=40) were included. Acoustic analyses were performed by the Multi-Dimensional Voice Program (MDVP; Kay Elemetrics Corporation, Lincoln Park, NJ) and the movements of the vocal cords were examined by videolaryngostroboscopy (VLS). In addition, the duration of illness, maximum phonation time, "s/z" values, and vital capacity were evaluated. Voice Handicap Index (VHI) and GRB scales were used for subjective evaluations. RESULTS: Maximum phonation time values were significantly shorter both in male and female asthma patients compared with controls (P<0.0001). Also, average shimmer values in MDVP were higher for both sexes in the patient group compared with controls (P=0.002 and P=0.04, respectively). There was a significant difference between female patients and sex-matched controls with regard to mean noise-to-harmonic ratio values (P=0.006). Female patients with asthma had higher average jitter values compared with sex-matched controls (P<0.0001). A significant difference was noted between asthma and control groups with regard to GRB scale (P<0.0001, P<0.001, and P<0.0001, respectively). The VHI score was above the normal limit in 16 (40%), and VLS findings were abnormal in 39 (97.5%) asthmatics. CONCLUSION: In asthmatic patients, maximum phonation time, frequency, and amplitude perturbation parameters were impaired, but the vital capacity and the duration of illness did not correlate with these findings. 相似文献
40.
H. Turgay Kaptanolu 《Journal of Functional Analysis》2007,250(2):483-520
Carleson and vanishing Carleson measures for Besov spaces on the unit ball of are characterized in terms of Berezin transforms and Bergman-metric balls. The measures are defined via natural imbeddings of Besov spaces into Lebesgue classes by certain combinations of radial derivatives. Membership in Schatten classes of the imbeddings is considered too. Some Carleson measures are not finite, but the results extend and provide new insight to those known for weighted Bergman spaces. Special cases pertain to Arveson and Dirichlet spaces, and a unified view with the usual Hardy-space Carleson measures is presented by letting the order of the radial derivatives tend to 0. Weak convergence in Besov spaces is also characterized, and weakly 0-convergent families are exhibited. Applications are given to separated sequences, operators of Forelli–Rudin type, gap series, characterizations of weighted Bloch, Lipschitz, and growth spaces, inequalities of Fejér–Riesz and Hardy–Littlewood type, and integration operators of Cesàro type. 相似文献