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Hailey-Hailey disease (HHD) is a rare autosomal dominant genodermatosis. It is characterized clinically by recurrent erosions, blisters and erythematous plaques at the sites of friction and intertriginous areas. The pathogenic gene of HHD was reported to be the ATPase calcium-transporting type 2C member 1 gene (ATP2C1). In this study, genomic DNA polymerase chain reaction (PCR) and direct sequencing of ATP2C1were performed from 3 Chinese pedigrees and 4 sporadic cases of HHD. We detected 3 heterozygous mutations, including 2 novel mutations (c.1673_1674insGTTG and c.2225A>G) and 1 recurrent nonsense mutation (c.1402C>T; NM_014382.4). The ATP2C1gene was also screened in the asymptomatic members of pedigrees. Our results would further expand the mutation spectrum of the ATP2C1gene and be helpful in the genetic counseling of patients with HHD.

A short, scalable, and collective total synthesis of four fawcettimine-type Lycopodiumalkaloids in eight or nine steps is disclosed. A dense multi-small-ring spiro-α-aminocyclopentanone successfully served as the key intermediate, which was directly accessed by a LiDBB-mediated intramolecular reductive coupling of the aliphatic imine and an ester-carbonyl. Compared to those that employ classical Heathcock intermediate(s) containing a nine-membered ring, the new strategy shows the significant improvement of the synthetic step and redox economies as well as excellent stereochemical control.

In recent years, silicon carbide (SiC) and other wide band gap semiconductors have become one of the strategic commanding heights in the global high-technology field. Silicon Carbide (SiC) metal-oxide-semiconductor field effect transistor (MOSFET) has shown excellent electrical properties. When applying SiC MOSFET, the safe operation area (SOA) need to be considered. In this paper, the effect of circuit parameters on RBSOA of SiC MOSFET is researched. Firstly, the principle of RBSOA is introduced. Secondly, the equivalent circuit of the single-pulse test circuit is shown to study on the effect of gate resistance and gate voltage on RBSOA. Thirdly, the simulation of variable parameters are done to research the variation trend. Finally, experiments are done to verify the results which can make an important influence on safe operation of SiC MOSFET and help choose suitable circuit parameters.

Capacitor banks are used widely in many different regions. Since seismic requirements are different from place to place, custom design is needed. Finite element simulation is used to help designers in this paper. All mechanical response of capacitor bank in different load cases are calculated. With these simulation support, custom design of capacitor banks is done for different regions safely and effectively.

The reliability of the gas turbo-supercharger can be affected by the faults such as the cauterization of the floating bearing of the supercharger, the carbonization of the rotor and getting stuck, the deformation of the blade and heat cracking of the nozzle ring. The design scheme is proposed by using friction bearing taking the place of the floating bearing, because the main reason of the cauterization of the bearing is the increase of the inside clearance of the floating sleeve, which is testified by the actual rpm measurement of the floating sleeve on the floating bearing and the adjustment test of the inside and outside clearances of the bearing. The experimental study on the structural characteristics of turbocharger bearing effectively prevents turbo-supercharger floating bearing from being cauterized, solves the problem of thermal fatigue damage, and improves turbocharger reliability.

To verify the feasibility of micro-filtration membrane process to treat the water treatment plants production wastewater, a submerged polypropylene membrane module was applied in a test pilot plant. It was found that membrane process had remarkable characteristics of stable operation, high water quality and the membrane module were needed to chemical medicine washing as trans-membrane pressure (TMP) to 36 Kpa after running across 41day. The operation cycle was the best period for 20 minutes (filter 18 minutes, backwash 2 minutes). Membrane filtration water was showed as turbidity of 0.1-0.2NTU, CODMn generally less than 3mg / L, CODMn removal efficiency of 60% -80%.Fe2 +, Mn2 +,Al3 + and THMFP of membrane filtration water were lower than the national drinking water health standards.

A new photocyclization strategy by using intermolecular tandem reactions between N‐(ω‐hydroxyalkyl)‐4,5,6,7‐tetrachlorophthalimides (1, 2, and 3) and a series of acyclic and cyclic alkenes is reported. Electron transfer of the triplet‐excited phthalimide with the alkene and regioselective trapping of the alkene cation radical by the hydroxyl group at the phthalimide side chain gives a triplet 1,n‐biradical, which after intersystem crossing (ISC) leads to regio‐ and diastereoselective synthesis of polycyclic heterocycles with an N,O‐containing medium to large ring. Regio‐ and diastereoselectivity in the cyclizations are clarified by unambiguous steric structure assignments of the products by X‐ray diffraction or extensive 2D NMR measurements. The diastereoselectivity is decided by the stereochemical course of the ISC process of the triplet 1,n‐biradicals. These intermolecular photoreactions also furnish a new strategy to generate triplet 1,n‐biradicals. Therefore, in photoreactions of 1and 2with phenylcyclohexene, the unprecedented stereoselective formation of products by intramolecular hydrogen‐atom transfer in the 1,n‐biradical intermediate was found (9and 23). These facts provide direct verification to the reaction pathways of the 1,n‐biradicals and give a new insight into the factors deciding reaction‐pathway partitioning and stereoselectivity.

Surge oscillations in a differential surge chamber have two degrees of freedom and are characterized by nonlinearities. The linear approximation provides stability criteria for small perturbations around the equilibrium state, and the Thoma stability criterion applies to the differential chamber. Large surge oscillations are investigated with direct numerical integration on two phase planes. The analysis indicates that the system reveals itself as a supercritical Hopf bifurcation—the exchange of stability from an asymptotically stable spiral to an unstable spiral approaching a stable limit cycle. The total chamber area is the controlling parameter. The bifurcation point corresponds to the Thoma criterion. For a surge chamber with an‐area larger than the Thoma value, an unstable limit cycle may exist around the equilibrium state on each phase plane, and it defines the domain of asymptotic stability. If the chamber area is less than the Thoma value, the case of soft self‐excitation with a stable limit cycle inside and an unstable one outside may occur, Stability in the large and instability in the small dominate the system.

The throttling orifice is introduced into air-cushion surge chambers to improve stability. The presence of the orifice adds another nonlinear term to the dynamic system, and its effect becomes predominant for oscillations with large displacements. By means of linearization, the type of singularities in the phase plane and their stability criteria in case of small oscillations are identified. The nonlinear analysis by direct numerical integration indicates that the system manifests itself as Hopf bifurcation with the surge-chamber size as its controlling factor. The bifurcation point corresponds to Svee's stability criterion. Before bifurcation, an unstable limit cycle may occur around the equilibrium state of practical interest, and it defines the domain of asymptotic stability. After bifurcation, two limit cycles may occur. Because of the existence of the stable one, the chamber size can be smaller than that specified by the Svee criterion. The orifice has stabilizing effect on surge motions.

The governing equations for surge oscillations in a closed surge chamber yield a second-order nonlinear differential equation for constant power. The surge stability is investigated by the direct method of Liapunov, which introduces the Liapunov function from the energy consideration. The nonlinear terms arising from large surges are included. The resulting stability criterion is demonstrated on a phase plane. For the equilibrium point of practical interest, the stability diagram specifies domains of asymptotic stability as a function of the safety factor of the surge-chamber. The diagram indicates that large-amplitude surges necessitate larger chamber size than that laid down by Svee for damping and the surge stability deteriorates with downward oscillations. By postulating sinusoidal surge motion, the critical chamber area is equal to the product of the critical area in case of small oscillations (Svee's formula) and a factor greater than 1.0. The factor is a function of surge amplitude and air cushion parameters for given turbine head. Stability criteria for open surge tanks can be obtained as special cases of those for closed ones.

The stability of water-surface oscillations is investigated for the case of a tailrace surge chamber shared by two or more generating units in a hydroelectric power plant. Two kinds of turbine governing are applied for the condition of small-amplitude surge perturbations. Critical stability conditions for the surge chamber are derived by linearizing the ordinary differential equations describing the lumped system. As compared with the result achieved by previous researchers, the common surge chamber requires smaller horizontal crosssection for surge stability. A combination of the proposed manners of governing can be utilized in certain power plants in order to achieve an economical design of the surge chambers.

The energy concept sheds light upon the hydraulic system that comprises the throttled surge tank, the tunnel and the penstock. The mathematical manipulation of the governing differential equations of water hammer yields an energy (power) equation in point form. By integration with respect to pipe distance, this relation is extended first to an individual pipe, then to the surge-tank system with branching connection. The system energy (power) equation states the relationship between the total (internal plus kinetic) energy, the convective energy, the work done on the system and the energy dissipation. A case study identifies the conversion between the internal and kinetic energy, and quantifies the behaviour and magnitudes of related energy components of the system.

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