An incumbent seller contracts with a buyer under the threat of entry. The contract stipulates price and penalty for breach if later switches to entrant. Sellers are heterogenous in terms gross surplus they provide buyer. is privately informed on her valuation incumbent’s service. Asymmetric information makes favor entry as it helps screening buyers. When entrant has some bargaining power vis-à-...

Based on the deformation and damage characteristics of surrounding rock in a large-section gob-side entry retaining combined with field observations an analysis dominant factors, overall control plan is formulated. The mainly includes structure high strength, stiffness ductility for roadside support; reinforcement roadway-in setup hydraulic fracturing pressure release mechanism advanced long, h...

The paper describes a distributed temperature sensing system that was used to monitor the artificial freezing of soils during construction potash mine shaft. technique reconstructing field by solving inverse problem in entire volume frozen using measured temperatures four thermal monitoring (TM) wells is described. Two local anomalies distributions TM are described and analyzed theoretically th...

BACKGROUND The water entry of a submersible aircraft, which is transient, highly coupled, and nonlinear, is complicated. After analyzing the mechanics of this process, the change rate of every variable is considered. A dynamic model is build and employed to study vehicle attitude and overturn phenomenon during water entry. Experiments are carried out and a method to organize experiment data is ...

Markets for experience or credence goods can suffer from adverse selection. The negative implication for trading and welfare poses the question of how such markets originate. We consider entry in markets in which each seller’s quality becomes private information. Entry lowers prices, which can trigger adverse selection. The anticipated price collapse limits entry so that high prices are sustain...

The first enantioselective Pd-catalyzed construction of all-carbon quaternary stereocenters via 1,4addition of arylboronic acids to β-substituted cyclic enones is reported. Reaction of a wide range of arylboronic acids and cyclic enones using a catalyst prepared from Pd(OCOCF3)2 and a chiral pyridinooxazoline ligand yields enantioenriched products bearing benzylic stereocenters. Notably, this t...

Since their discovery, cyclodextrins have widely been used as green and easily available alternatives to promoters or catalysts of different chemical reactions in water. This review covers the research and application of cyclodextrins and their derivatives in asymmetric and stereospecific syntheses, with their division into three main groups: (1) cyclodextrins promoting asymmetric and stereospe...