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81.
We consider an agency problem where a firm (she) hires a manager (he) who has related managerial expertise to implement a new project. The manager’s managerial expertise is his private information and characterized as an uncertain variable. The revenue brought about by the project in the future is also assumed to be uncertain. In light of these challenges, this paper investigates the impacts of the manager’s risk attitude and the type-and-effort dependent outside option on the optimal compensation contracts under different information structures. Through developing the manager’s decision criterion based on his risk attitude instead of the expected-utility-maximization criterion, we find that, if the manager is conservative and the outside option’s revenue uncertainty is sufficiently high, the optimal commission rate will be distorted upwards under asymmetric managerial expertise information compared with that under symmetric managerial expertise information. Our analysis also confirms that the existence of a type-and-effort dependent outside option distorts up the compensation structure tailored at a fixed outside option. We further show that, comparing with the setting of a fixed outside option when the manager is aggressive, the presence of a type-and-effort dependent outside option results in a surprising phenomenon that the manager’s private information makes no distortion of the firm’s profit. 相似文献
82.
Poly(?-caprolactone-co-1,2-butylene carbonate) (PBCCL) was successfully synthesized via terpolymerization of carbon dioxide, 1,2-butylene oxide(BO) and ?-caprolactone (CL). A polymer-supported bimetallic complex (PBM) was used as catalyst. The influences of various reaction conditions such as reaction content, reaction time and reaction temperature on properties of terpolymers were investigated. When CL content increased, the viscosity-average molecular weights (Mv), glass transition temperature (Tg) and decomposition temperature (Td) of PBCCL improved relative to those of poly(1,2-butylene carbonate) (PBC). Prolonging the reaction time resulted in increase in Mv and Tg. As reaction temperature increased, the molar fractions of CL (fCL) increased obviously. When the reaction temperature went beyond 80 °C, the resulting copolymers tended to be crystalline. The thermal properties and degradation behaviors of PBCCL were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The apparent activation energy and thermal degradation model of PBCCL was estimated by means of Ozawa-Flynn-Wall method and Phadnis-Deshpande method, respectively. The results showed that Tg and Td of the terpolymer PBCCL were much higher than those of PBC. The thermal degradation behavior of PBCCL was evidenced by one-step thermal degradation profile. The average apparent activation energy is 77.06 kJ/mol, the thermal degradation kinetics follows the power law thermal decomposition model. 相似文献
83.
Yanfei Yang 《Tetrahedron》2010,66(2):447-454
A series of calix[4]arene-dithiacrown-5 and -dithiacrown-6 compounds in cone and 1,3-alternate conformations has been synthesized. Responses of these ionophores to Hg2+ and competing metal ions were determined in solvent polymeric membrane electrodes. High potentiometric selectivity for Hg2+ over Na+ and a variety of transition and heavy metal ions was obtained. 相似文献
84.
85.
The direct ketohydroxylation of a variety of 1-aryl-1-alkenes with H2O2, catalyzed by the inexpensive 12-tungstophosphoric acid/cetylpyridinium chloride system under very mild conditions, was achieved. Various acyloins were obtained in good yields and high regioselectivies. 相似文献
86.
Yanfei Yang Xiaodan Cao Kazimierz Surowiec Richard A. Bartsch 《Journal of inclusion phenomena and macrocyclic chemistry》2010,66(1-2):163-169
A regioisomer of a previously reported p-tert-butylcalix[4]arene-1,3-thiacrown-5 di(carboxylic acid) is prepared in which the thiacrown ring attachment sites are moved from distal phenolic oxygens of a cone p-tert-butylcalix[4]arene scaffold to proximal phenolic oxygens. The influence of this structural variation in the di-ionizable calixcrown ligand on competitive solvent extractions of alkali metal cations and of alkaline earth metal cations and single species solvent extractions of Hg2+ and Pb2+ from aqueous solutions into chloroform is evaluated. 相似文献
87.
Lixia Chen Yang Zhang Xinming Zhang Ruijuan Lv Rongtian Sheng Ruimeng Sun Ting Du Yuhan Li Yanfei Qi 《Molecules (Basel, Switzerland)》2022,27(1)
Anticancer treatment is largely affected by the hypoxic tumor microenvironment (TME), which causes the resistance of the tumor to radiotherapy. Combining radiosensitizer compounds and O2 self-enriched moieties is an emerging strategy in hypoxic-tumor treatments. Herein, we engineered GdW10@PDA-CAT (K3Na4H2GdW10O36·2H2O, GdW10, polydopamine, PDA, catalase, CAT) composites as a radiosensitizer for the TME-manipulated enhancement of radiotherapy. In the composites, Gd (Z = 64) and W (Z = 74), as the high Z elements, make X-ray gather in tumor cells, thereby enhancing DNA damage induced by radiation. CAT can convert H2O2 to O2 and H2O to enhance the X-ray effect under hypoxic TME. CAT and PDA modification enhances the biocompatibility of the composites. Our results showed that GdW10@PDA-CAT composites increased the efficiency of radiotherapy in HT29 cells in culture. This polyoxometalates and O2 self-supplement composites provide a promising radiosensitizer for the radiotherapy field. 相似文献
88.
自从S.Nakamura等人成功地制备了GaN/GaInN/AlGaN蓝、绿光LEDs以来,GaN及其相关化合物的材料生长和器件工艺得到了广泛地研究.由于GaN材料不同于传统的Ⅲ-Ⅴ族化合物半导体材料,因此其器件的加工工艺,如欧姆或肖特基接触的形成、... 相似文献
89.
90.
综述了六苄基六氮杂异伍兹烷(HBIW)五种氢解脱苄化合物的合成条件和工业制备工艺。这五种化合物是:四乙酰基二苄基六氮杂异伍兹烷(TADBIW)、四乙酰基二甲酰基六氮杂异伍兹烷(TADFIW)、四乙酰基六氮杂异伍兹烷(TAIW)、四乙酰基二乙基六氮杂异伍兹烷(TADEIW)和六乙酰基六氮杂异伍兹烷(HAIW)。其中的TADBIW系由HBIW经一次氢解合成,其它四种都系由HBIW经两次氢解合成。HBIW的这五种氢解脱苄化合物均可经硝解合成六硝基六氮杂异伍兹烷(HNIW)。另外,本文总结了HBIW及其五种氢解脱苄产物的红外、核磁和质谱数据及它们的基本性能参数。 相似文献