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61.
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Some o-xylylene (o-quinodimethane) derivatives were isolated as stable cyrstalline materials. A strong through-bond interaction in tetracyanoethylene addition product of tetraphenylbenzodicyclobutadiene (21 is suggested.  相似文献   
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The synthesis of malachite CuCO3·Cu(OH)2 or Cu2CO3(OH)2 was studied through titrations of copper(II) salt solutions with a solution of sodium carbonate at different temperatures. The precipitates were characterized by TG, IR and chemical analysis. The composition varies depending on thepH of the solution and the temperature. Purer malachite was synthesized by simple mixing of a solution of copper(II) nitrate or sulfate with a solution of sodium carbonate at 50°C.The kinetics of the thermal decomposition of synthetic malachite was described by eitherR 3 orA m(m=1.2–1.4) law, according to TG analysis, both isothermal and nonisothermal. The Arrhenius parameters determined using three different integral methods showed the kinetic compensation effect, which is correlated to the working temperature interval analyzed.The authors thank Mr. H. Takemoto for analyzing kinetics of the thermal decomposition of synthetic malachite.  相似文献   
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Shiraishi K  Kawamura H  Tanaka G 《Talanta》1987,34(10):823-827
Alkaline-earth metals in human bone samples have been determined simultaneously by inductively-coupled plasma atomic-emission spectrometry (ICP-AES). Results obtained by atomic-absorption spectrometry for Mg, Sr and Ba, and complexometry for Ca, have been compared with those by ICP-AES for a laboratory-control bone sample. Accuracy and precision were examined by analysing the IAEA animal bone standard (H-5). Agreement with the certified values to within 5% was obtained. The concentrations of the elements in foetal bone have also been determined.  相似文献   
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A chiral HWE reagent reacted with an alternative carbonyl group of meso-α-diketones of bicyclo[2.2.1] system to give non-racemic (Z)- and (E)-olefins, respectively.  相似文献   
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The conjugate of mitomycin C (MMC) with linear (1----3)-beta-D-glucan from Alcaligenes faecalis var. myxogenes IFO 13140 was synthesized and its antitumor activities investigated. The conjugate (MMC-carboxymethylated linear (1----3)-beta-D-glucan (CMPS)) was obtained by treatment of CMPS with MMC in the presence of 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide. In vitro cytotoxicity of MMC-CMPS against L1210 leukemia cells was similar to that of MMC. In i.p.-i.p. system in vivo against P388 leukemia in mice, the maximum increase of MMC-CMPS conjugate in life span (ILSmax) was higher than that of MMC but the therapeutic index was reduced. However, the antitumor activity of MMC-CMPS conjugate against subcutaneously implanted sarcoma 180 solid tumor in mice by i.p. administration was similar to that of MMC at a dose of 1.5 mg eq MMC/kg/d x 7 and the reduction of the number of leukocytes caused by MMC was suppressed by attaching MMC to CMPS. In addition, on assay using serum of sarcoma 180 solid tumor-bearing mice with injection of MMC-CMPS conjugate, a drastic loss of tumor cells and an increase in polymorphonuclear leukocytes (PMN) were observed. This result suggested that MMC-CMPS conjugate induced tumor-regressing factor similar to CMPS.  相似文献   
70.
The title heterocyclic donors undergo reversible C? C bond formation/cleavage upon electron transfer (dynamic redox behavior). The helical sense in both neutral and cationic states is interconvertible by facile ring flipping. The π‐type asymmetric center on the azepine nitrogen atom induces a significant degree of diasteromeric preference, thus endowing strong CD activity based on exciton coupling. Chiroptical properties could be modified not only by redox reactions but also by heat and protonation. The present redox pairs can serve as unprecedented three‐way‐input (e, H+, Δ) and two‐way‐output (UV/Vis, CD) response systems.  相似文献   
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