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排序方式: 共有317条查询结果,搜索用时 15 毫秒
71.
Francisco J. N. Maia Viviane G. Ribeiro Claudenilson S. Clemente Diego Lomonaco Pedro H. M. Vasconcelos Selma E. Mazzetto 《Journal of Thermal Analysis and Calorimetry》2012,109(2):1013-1018
In this study, the thermo-oxidative stability of two new phosphorylated derivatives of cardol, a compound from the cashew (Anacardium occidentale L.) industry waste CNSL (cashew nutshell liquid), were evaluated. The antioxidant capacity of these new molecules upon two mineral oils, NH10 and NH20 were also studied by thermogravimetric analysis (TG/DTG), observing the onset and offset temperatures variation. The results showed that both MP and DP Cardol increased considerably the onset and offset temperatures of NH10 and NH20 oils. 相似文献
72.
73.
brahim Uar Figen Arslan Ahmet Bulut Hasan budak Hals
lmez Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(10):m523-m525
The crystal structure of the mononuclear title complex, [CuCl2(C10H8N4)(H2O)]·H2O, shows an s‐cis/E/s‐trans‐configured di‐2‐pyridyldiazene ligand, with the square‐pyramidal CuII ion coordinated to one pyridyl and one diazene N atom together with two Cl atoms and one aqua ligand. The crystal packing involves both hydrogen‐bonding and π–π interactions. The solvent water molecule links three monomers to one another through hydrogen‐bonding interactions in which two monomers are linked via chloro ligands and the third via the aqua ligand. Face‐to‐face and weak slipped π–π interactions also occur between di‐2‐pyridyldiazene moieties, and these interactions are responsible for the interchain packing. 相似文献
74.
Plasma Chemistry and Plasma Processing - 相似文献
75.
Vivian C. Selma Luís H. B. Cotrim José A. D. Rodrigues Suzana M. Ratusznei Marcelo Zaiat Eugenio Foresti 《Applied biochemistry and biotechnology》2010,162(8):2365-2380
The effect of organic matter and fill time on anaerobic sequencing batch reactor (5 L, 30°C, 8-h cycles, 50 rpm) efficiency
has been analyzed. Organic matter was increased by the influent concentration. Fill times investigated were in the batch mode
and fed-batch followed by batch. In the batch mode organic matter removal were 93%, 81%, and 66% for influent concentration
of 500, 1,000, and 2,000 mgCOD/L (0.6, 1.29, and 2.44 gCOD/L.d), respectively. At 3,000 mgCOD/L (3.82 gCOD/L.d) operational
stability could not be achieved. Removal efficiency was improved by increasing the fill time, and was 85% for the 1,000 mgCOD/L
condition and fill times of 2 and 4 h, and 80 and 77% for the 2,000 mgCOD/L condition and fill times of 2 and 4 h, respectively.
Hence, gradual feeding seemed to improve and to smooth the profiles of organic matter and volatile acids along the cycle with
78 to 96 NmLCH4/gCOD. 相似文献
76.
In this study, a novel phthalonitrile, ethyl 7-(3,4-dicyanophenoxy)coumarin-3-carboxylate (1), was prepared and characterized. The metallophthalocyanines (3–6) were prepared by cyclotetramerization of 1 with the corresponding metal salts {Zn(OAc)2·2H2O, Co(OAc)2·4H2O, Cu(OAc)2, Ni(OAc)2·4H2O} in 2-chloronaphthalene. Reaction of 3 with aqueous hydrochloric acid gave the coumarino-zincphthalocyanine (3a) carrying carboxyl groups at the 3-position of all the coumarin moieties. Treatment of compound 3a with aqueous NaOH./AgNO3 or aqueous NaOH in N,N-dimethylformamide (DMF) gave the expected silver (3c) or sodium (3d) salts, respectively. The four carboxylic groups in coumarino-zincphthalocyanine (3a) and the four carboxylate groups in 3d make the compounds have good solubility in water. Heating of the acyl chloride derivative of 3 with morpholine in DMF yielded the corresponding 3-carboxymorpholinamide (3b). The newly prepared compounds, phthalonitrile and metallophthalocyanines, have been characterized by FT-IR, UV–Vis, MALDI-TOF and 1H NMR spectroscopies. 相似文献
77.
Nilay Aladag Dilsat Ozkan‐Ariksoysal Duygu Gezen‐Ak Selma Yilmazer Mehmet Ozsoz 《Electroanalysis》2010,22(5):590-598
Electrochemical detection of nucleic acid base mismatches related to Apa I single nucleotide polymorphism (SNP) in the vitamin D receptor gene was performed successfully using 7‐dimethyl‐amino‐1,2‐benzophenoxazinium salt (Meldola's blue, MDB) with 10.9 pmol/100 μL of detection limit. MDB reduction signals obtained from probe, mismatch(probe‐SNP containing target) and hybrid(probe‐target) modified pencil graphite electrode(PGE) increased respectively. The sensor was able to clearly distinguish perfect match from mismatch DNA in a 30 min. detection time. Several factors affecting on the hybridization and indicator response are studied to maximize sensitivity and selectivity. The advantages of the biosensor are discussed in comparison with previous electrochemical assays for DNA hybridization. 相似文献
78.
A system with n independent components which has a k-out-of-n: G structure operates if at least k components operate. Parallel systems are 1-out-of-n: G systems, that is, the system goes out of service when all of its components fail. This paper investigates the mean residual life function of systems with independent and nonidentically distributed components. Some examples related to some lifetime distribution functions are given. We present a numerical example for evaluating the relationship between the mean residual life of the k-out-of-n: G system and that of its components. 相似文献
79.
In this study, we survey the history of mathematics education in Turkey starting with its historical roots in the foundation of the republic. The changes in mathematics education in Turkey over the last century are investigated through an analysis of changes in curricular documents for K-12 schools. We consider the factors and reasons affecting curriculum developments, changes in philosophy and structure in terms of standards, objective and instructions. This article utilizes archival research techniques by examining original sources and illustrates the nature of the changes benefiting from a historical perspective. As a result of such analysis of the aforesaid sources, we have seen that the main reasons for changing mathematics curricula are: to build up a modern civilization in Turkey; the reports of John Dewey and the recommendations of Kate Wofford, William C. Varaceus and Watson Dickerman; the desire to become a member of the European Union; international factors and political situations. 相似文献
80.
Yusuf Gurefe Yusuf Pandir Tolga Akturk Hasan Bulut 《Journal of Applied Analysis & Computation》2017,7(1):372-391
In this work, we have constructed various types of soliton solutions of the generalized regularized long wave and generalized nonlinear Klein-Gordon equations by the using of the extended trial equation method. Some of the obtained exact traveling wave solutions to these nonlinear problems are the rational function, 1-soliton, singular, the elliptic integral functions $F, E, \Pi$ and the Jacobi elliptic function sn solutions. Also, all of the solutions are compared with the exact solutions in literature, and it is seen that some of the solutions computed in this paper are new wave solutions. 相似文献