In this paper, the different mechanical behaviors of layered rocks with different bedding angles during uniaxial compression tests are studied. Numerical simulation models of layered rock are validated based on laboratory tests, and uniaxial compression tests are conducted by using Particle Flow Code (PFC). Using these simulations, the uniaxial compressive strength, failure patterns, development of micro-cracks, and displacement of meso particles are analyzed. When the bedding angle is similar to the failure angle, the macro failure planes develop directly along the beddings, the bedding behavior dictates the behavior of the layered rock, reducing the compressive strength.

In order for the working status of the aluminum alloyed hydraulic valve body to be controlled in actual conditions, a new friction and wear

design device was designed for the cast iron and aluminum alloyed valve bodies comparison under the same conditions. The results

displayed that: (1) The oil leakage of the aluminum alloyed hydraulic valve body was higher than the corresponding oil leakage of the iron

body during the initial running stage. Besides during a later running stage, the oil leakage of the aluminum alloyed body was lower than

corresponding oil leakage of the iron body; (2) The actual oil leakage of different materials consisted of two parts: the foundation leakage

that was the leakage of the valve without wear and wear leakage that was caused by the worn valve body; (3) The aluminum alloyed valve

could rely on the dust filling furrow and melting mechanism that led the body surface to retain dynamic balance, resulting in the valve

leakage preservation at a low level. The aluminum alloy modified valve body can meet the requirements of hydraulic leakage under

pressure, possibly constituting this alloy suitable for hydraulic valve body manufacturing.

Owing to the dramatic change in the thermal conductivity of 4He when its temperature crosses the transition of superfluid (HeI) and normalfluid (HeII), a sealed-cell with a capillary is used to realize the lambda transition temperature, Tλ. A small heat flow is controlled through the capillary of the sealed-cell so as to realize the coexistence of HeI and HeII and maintain the stay of HeI/HeII interface in the capillary. A stable and flat lambda transition temperature "plateau" is obtained. Because there is a depression effect of Tλ caused by the heat flow through the capillary, a series of heat flows and several temperature plateaus are made and an extrapolation is applied to determine Tλ with zero heat flow. A rhodium-iron resistance thermometer with series number A34 (RIRT A34) has been used in 24 Tλ -realization experiments to derive Tλ with a standard deviation of 0.022mK, which proves the stability and reproducibility of Tλ.

In the external target experiment for heavy ion collisions in the HIRFL-CSR, Multi-Wire Drift Chambers are used to measure the drift time of charged particles to obtain the track information. This 128-channel high precision time measurement module is designed to perform the time digitization. The data transfer is based on a PXI interface to guarantee a high data rate. Test results show that a 100 ps resolution with a data transfer rate up to 40 MBps has been achieved; this module has also been proven to function well with the detector through a commissioning test.