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101.
102.
Jerzy Zakrzewski 《合成通讯》2013,43(16-17):2135-2140
A simple route to the hindered chloramines, starting from the corresponding hindered amines is reported. Sodium dichlorisocyanurate is the chlorinating agent.  相似文献   
103.
A multicommutated flow analysis (MCFA) system constructed of microsolenoid valves and pumps offering simultaneous determination of activity of acid phosphatase (ACP) and alkaline phosphatase (ALP) in human serum samples has been developed. The MCFA system is based on optoelectronic flow-through detector made of two light emitting diodes and operating according to paired emitter detector diode (PEDD) principle. This photometric PEDD device has been dedicated for detection of p-nitrophenol (NP) generated in the course of enzymatic hydrolysis of p-nitrophenyl phosphate and optimized for the determination of NP in human serum samples. The developed PEDD-based MCFA system allows independent optimization of conditions for reaction and detection steps of photometric ACP and ALP bioassays. Moreover, it allows elimination of photometric interferences from serum matrix components according to two-points kinetic mode of measurement. The single measurement cycle takes 12 min, consists of four measurements (two for each phosphoesterase) and enables determination of serum ACP and ALP activities at physiological and pathological levels. The real analytical utility of the developed MCFA system has been confirmed by analysis of control sera as well as real human serum samples from healthy persons and oncological patients.  相似文献   
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This study focused on the synthesis and subsequent characterization of herbicidal ionic liquids based on betaine and carnitine, two derivatives of amino acids, which were used as cations. Four commonly used herbicides (2,4‐D, MCPA, MCPP and Dicamba) were used as anions in simple (single anion) and oligomeric (two anions) salts. The obtained salts were subjected to analyzes regarding physicochemical properties (density, viscosity, refractive index, thermal decomposition profiles and solubility) as well as evaluation of their herbicidal activity under greenhouse and field conditions, toxicity towards rats and biodegradability. The obtained results suggest that the synthesized herbicidal ionic liquids displayed low toxicity (classified as category 4 compounds) and showed similar or improved efficacy against weed compared to reference herbicides. The highest increase was observed during field trials for salts containing 2,4‐D as the anion, which also exhibited the highest biodegradability (>75 %).  相似文献   
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Abstract

Aspects of the reactivity of metallophosphanes are presented along with the synthesis and structure determinations for new aluminophosphanes.  相似文献   
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For wide classes of locally convex spaces, in particular, for the space C p ( X ) of continuous real‐valued functions on a Tychonoff space X equipped with the pointwise topology, we characterize the existence of a fundamental bounded resolution (i.e., an increasing family of bounded sets indexed by the irrationals which swallows the bounded sets). These facts together with some results from Grothendieck's theory of ( D F ) ‐spaces have led us to introduce quasi‐ ( D F ) ‐spaces, a class of locally convex spaces containing ( D F ) ‐spaces that preserves subspaces, countable direct sums and countable products. Regular ( L M ) ‐spaces as well as their strong duals are quasi‐ ( D F ) ‐spaces. Hence the space of distributions D ( Ω ) provides a concrete example of a quasi‐ ( D F ) ‐space not being a ( D F ) ‐space. We show that C p ( X ) has a fundamental bounded resolution if and only if C p ( X ) is a quasi‐ ( D F ) ‐space if and only if the strong dual of C p ( X ) is a quasi‐ ( D F ) ‐space if and only if X is countable. If X is metrizable, then C k ( X ) is a quasi‐ ( D F ) ‐space if and only if X is a σ‐compact Polish space.  相似文献   
110.
Nonlinear Dynamics - This paper examines the oscillations of a spherical pendulum with horizontal Lissajous excitation. The pendulum has two degrees of freedom: a rotational angle defined in the...  相似文献   
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